10.14639/0392-100X-N1837
A parotid abscess is a dangerous complication of parotitis. In this study, we aimed to define current treatment concepts for parotid abscess, focusing on different management options. The authors performed a PRISMA-compliant systematic review across multiple databases including all original studies published until January 2021 focusing on treatment of parotid abscess. Studies specifying treatment modalities and treatment success rates were included based on abstract and full-text selection. The authors assessed study quality, demographics, success rates, management modalities and adverse events. Among 1,318 citations, 18 studies met our inclusion criteria. Twelve studies relied only on incision and drainage with antibiotic therapy; the remaining 6 compared different treatment modalities (incision and drainage versus exclusive medical therapy or ultrasound-guided drainage). Heterogeneity between studies precluded meta-analysis of data. The review showed that antibiotics remain the mainstay of treatment for parotid abscess. Conversely, the role of incision and drainage, and aspiration should be studied further. The higher rate of complications following incision and drainage suggests a more conservative approach is needed. Incision and drainage remain the main salvage option for conservative treatment failures.
text/xml
1827-675X
1837
en
Carlos M. Chiesa-Estomba
http://creativecommons.org/licenses/by-nc-nd/4.0
ACTA Otorhinolaryngologica Italica
parotitis
Treatment for parotid abscess: a systematic review
Text.Serial.Journal
https://www.actaitalica.it/
42
Reviews
2022-05-16
2021-09-30
2022-05-23
2022-05-23
106-115
1
Carlos M. Chiesa-Estomba
2022/05/16
10.14639/0392-100X-N1837
106
International Federation of Otorhinolaryngological Societies (YO-IFOS) Head and Neck Research Group, Paris, France; Department of Otorhinolaryngology - Head and Neck Surgery, Hospital Universitario Donostia/ Biodonostia Research Institute, San Sebastian, Spain
1827-675X
parotitis
en
115
Treatment for parotid abscess: a systematic review
https://www.actaitalica.it/article/download/1837/786
42
ACTA OTORHINOLARYNGOLOGICA ITALICA 2022;42:106-115; doi: 10.14639/0392-100X-N1837




Review


Treatment for parotid abscess: a systematic review
Trattamento degli ascessi parotidei: revisione sistematica della letteratura
Alberto Maria Saibene1,2*, Fabiana Allevi1,3*, Tareck Ayad1,4 , Jérome R. Lechien1,5, Miguel Mayo-Yáñez1,6,7,
Krzysztof Piersiala1,8, Carlos M. Chiesa-Estomba1,9
1
  International Federation of Otorhinolaryngological Societies (YO-IFOS) Head and Neck Research Group, Paris, France;
2
  Otolaryngology Unit, Santi Paolo e Carlo Hospital, Department of Health Sciences, Università degli Studi di Milano, Milan,
Italy; 3 Maxillofacial Surgery Unit, Santi Paolo e Carlo Hospital, Department of Health Sciences, Università degli Studi di Milano,
Milan, Italy; 4 Division of Otolaryngology-Head and Neck Surgery, Centre Hospitalier de L’Université de Montréal, Montreal, QC,
Canada; 5 Department of Otolaryngology-Head and Neck Surgery, Foch Hospital, Paris Saclay University, Saint-Aubin, France;
6
  Otorhinolaryngology − Head and Neck Surgery Department, Complexo Hospitalario Universitario A Coruña (CHUAC), 15006,
A Coruña, Galicia, Spain; 7 Clinical Research in Medicine, International Center for Doctorate and Advanced Studies (CIEDUS),
Universidade de Santiago de Compostela (USC), 15782, Santiago de Compostela, Galicia, Spain; 8 Department of Clinical Science,
Intervention and Technology (CLINTEC), Karolinska Institutet, Stockholm, Sweden; 9 Department of Otorhinolaryngology - Head and
Neck Surgery, Hospital Universitario Donostia/ Biodonostia Research Institute, San Sebastian, Spain
*
 A.M. Saibene and F. Allevi contributed equally to this work.


SUMMARY
A parotid abscess is a dangerous complication of parotitis. In this study, we aimed to define
current treatment concepts for parotid abscess, focusing on different management options.
The authors performed a PRISMA-compliant systematic review across multiple databases
including all original studies published until January 2021 focusing on treatment of parotid
abscess. Studies specifying treatment modalities and treatment success rates were included
based on abstract and full-text selection. The authors assessed study quality, demograph-
ics, success rates, management modalities and adverse events. Among 1,318 citations, 18
studies met our inclusion criteria. Twelve studies relied only on incision and drainage with
antibiotic therapy; the remaining 6 compared different treatment modalities (incision and
drainage versus exclusive medical therapy or ultrasound-guided drainage). Heterogeneity
between studies precluded meta-analysis of data. The review showed that antibiotics remain
the mainstay of treatment for parotid abscess. Conversely, the role of incision and drainage,     Received: September 30, 2021
                                                                                                  Accepted: January 30, 2022
and aspiration should be studied further. The higher rate of complications following inci-
sion and drainage suggests a more conservative approach is needed. Incision and drainage
                                                                                                  Correspondence
remain the main salvage option for conservative treatment failures.
                                                                                                  Alberto Maria Saibene
KEY WORDS: salivary gland, sialadenitis, antibiotics, drainage, parotitis                         Otolaryngology Unit, ASST Santi Paolo e Carlo,
                                                                                                  via Antonio di Rudinì 8, 20142 Milan, Italy
                                                                                                  Tel. +39 02 8184 4249. Fax +39 02 5032 3166
RIASSUNTO                                                                                         E-mail: alberto.saibene@gmail.com
Gli ascessi parotidei rappresentano una complicanza della parotite. Questo studio mira a
definire i concetti moderni di trattamento di questa patologia e le diverse scelte di gestione.     How to cite this article: Saibene AM, Al-
È stata eseguita una revisione sistematica della letteratura secondo il protocollo PRISMA           levi F, Ayad T, et al. Treatment for parotid
degli studi originali sul trattamento degli ascessi parotidei, pubblicati sino al Gennaio           abscess: a systematic review. Acta Otorhi-
2021. Gli studi riportanti modalità di trattamento e tasso di successo sono stati inclusi dopo      nolaryngol Ital 2022;42:106-115. https://doi.
selezione basata su abstract e full-text, valutando qualità degli studi, caratteristiche dei        org/10.14639/0392-100X-N1837
pazienti, tasso di successo, modalità di trattamento ed eventi avversi. Su 1318 citazioni, 18
studi rispettavano i criteri di inclusione, 12 basati su incisione e drenaggio e 6 comparanti     © Società Italiana di Otorinolaringoiatria
                                                                                                  e Chirurgia Cervico-Facciale
diversi trattamenti (incisione e drenaggio versus terapia medica esclusiva o drenaggio eco-
guidato). L’eterogeneità degli studi non ha consentito la realizzazione di una meta-analisi.
                                                                                                                 OPEN ACCESS
Gli antibiotici si confermano il punto fermo del trattamento degli ascessi parotidei. Il ruolo
di drenaggi chirurgici ed eco-guidati dovrebbe essere invece maggiormente esplorato. Il           This is an open access article distributed in accordance with
                                                                                                  the CC-BY-NC-ND (Creative Commons Attribution-Non-
maggiore tasso di complicanze dopo incisione e drenaggio suggerisce un approccio più
                                                                                                  Commercial-NoDerivatives 4.0 International) license. The
conservativo. Incisione e drenaggio restano la principale risposta al fallimento della tera-      article can be used by giving appropriate credit and mentio-
pia conservativa.                                                                                 ning the license, but only for non-commercial purposes and
                                                                                                  only in the original version. For further information: https://
PAROLE CHIAVE: ghiandole salivari, scialoadenite, antibiotici, drenaggio, parotite                creativecommons.org/licenses/by-nc-nd/4.0/deed.en




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                                                                                                         Treatment for parotid abscess




Introduction                                                       • Comparator: different PA management options (as de-
                                                                     scribed in the intervention criterion);
Treatment of parotid abscesses (PA) represents another itera-
                                                                   • Outcome: treatment success (defined as clinical evi-
tion of empiric application of the Latin adage “Ubi pus, ibi
                                                                     dence of infection resolution) as the primary outcome,
evacua”. They might be regarded just like any other deep
                                                                     treatment complications as a secondary outcome;
neck space abscess, where pus evacuation is required to pre-
                                                                   • Time: short term outcomes;
vent fasciitis and allow antibiotics to reach the infection site
                                                                   • Setting: specialty care for patients admitted for PA.
with adequate perfusion 1. Nevertheless, the well-known an-
atomical peculiarities of the parotid space (most notably the
                                                                   Search strategy
presence of the facial nerve), make their management defi-
                                                                   The review was performed between January 18 and April
nitely more complex 2,3. Parotitis, which represents the most
                                                                   10, 2021. We conducted systematic searches for studies in
common inflammatory disease of the parotid gland, only
                                                                   English, Italian, German, French, or Spanish, published
sporadically evolves into PA 4. PA is more common among
                                                                   until the search date and reporting original data. On Janu-
elderly or immunocompromised patients 2, but their presen-
                                                                   ary 18, 2021, we searched the MEDLINE, Embase, Web
tation in immunocompetent healthy children and adults is
                                                                   of Science, Cochrane Library, and ClinicalTrials.gov da-
well documented in clinical practice 5. PA is frequently due
                                                                   tabases with wide search strategies for all salivary gland
to S. aureus infection 6 and are usually managed with a com-
                                                                   abscesses to maximise the results. Full searcs details and
bination of intravenous antibiotics and abscess incision and
                                                                   results are detailed in Table I.
drainage 7. Nevertheless, treatment options such as abscess
                                                                   We included any study dealing, entirely or partly, with the
aspiration (with or without radiological guidance) or simple
                                                                   treatment of PA in humans. We excluded meta-analyses,
medical management have been reported systematically in
                                                                   systematic and narrative reviews, grey literature, pre-clin-
the literature 8,9. Often different treatment options are also
                                                                   ical studies and case reports. References from review arti-
employed simply according to the clinicians’ preference,
                                                                   cles were hand-checked for additional potentially relevant
even in the context of the same head and neck team 5,7.
This evolution in PA management follows a common de-es-            studies. No minimum study population was required. We
calation trend in management of deep neck spaces. Prelimi-         included only studies that specified treatment modalities
nary prospective and meta-analytic data show that aspiration       and treatment outcomes and excluded studies focusing sys-
or exclusive medical management of neck abscess may yield          tematically on mycobacterial abscesses.
results that are non-inferior to incision and drainage, while      Abstracts and full texts were reviewed in duplicate by dif-
obviously reducing procedural complications 10,11.                 ferent authors. At the abstract stage, we included all studies
The present literature on PA treatment is characterised by         deemed eligible by at least one rater. At the full-text review
small studies and a general lack of prospective data, and          stage, disagreements were resolved by consensus.
it is therefore unable to provide guidance in the choice of
treatment. In this context, we conducted a systematic re-          Data extraction and quality assessment
view to define current concepts in PA management, mainly           For each article, we recorded the number of PA patients,
focusing on the following approaches: incision and drain-          male to female ratio, patient age, potential focus on spe-
age, aspiration, and exclusive medical treatment.                  cific subpopulations, abscess diagnostic modalities, PA
                                                                   treatments (which were classified between incision and
                                                                   drainage, i.e. skin or oral open incision with abscess drain-
Materials and methods                                              age; aspiration, i.e. radiology-guided or unguided needle
This systematic review was performed respecting PRISMA             aspiration without incision; and exclusive medical therapy,
Statement 12 and PICOTS criteria. Its protocol is regis-           i.e. without any local invasive procedure associated), anti-
tered and publicly available in the International Prospec-         biotic treatment(s), therapeutic success, complications and
tive Register of Systematic Reviews (PROSPERO) (no.                microbial cultures.
CRD42021231347).                                                   Studies were assessed with the National Heart, Lung, and
                                                                   Blood Institute Study Quality Assessment Tools (NHI-
PICOTS criteria                                                    SQAT) 13. Articles were rated in duplicate by two authors
The PICOTS criteria for this review were:                          and disagreements were resolved by consensus. Articles
• Patients: patients with radiologically or clinically diag-       were rated as good, fair, or poor if they fulfilled, respec-
  nosed PA;                                                        tively, at least 80% of the items required by the NHI-SQAT,
• Intervention: PA incision and drainage, aspiration or ex-        between 50% and 80% of the items, and less than 50% of
  clusive medical therapy;                                         the items.



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A.M. Saibene et al.




Table I. Search keys and results for each database consulted.
 Database                                                                  Search key                                                         Date of     No. of
                                                                                                                                              search      items
 Medline                  ((“parotid gland”[MeSH Terms] OR (“parotid”[All Fields] AND “gland”[All Fields]) OR “parotid gland”[All Fields]     January      581
                              OR “parotid”[All Fields] OR “parotids”[All Fields] OR “parotid”[All Fields] OR “parotideal”[All Fields]) AND   18th, 2021
                            (“abscess”[MeSH Terms] OR “abscess”[All Fields] OR “abscesses”[All Fields] OR “abscessation”[All Fields]
                              OR “abscessed”[All Fields] OR “abscessing”[All Fields])) OR (“salivary”[All Fields] AND (“abscess”[MeSH
                          Terms] OR “abscess”[All Fields] OR “abscesses”[All Fields] OR “abscessation”[All Fields] OR “abscessed”[All
                               Fields] OR “abscessing”[All Fields])) OR ((“sialadenitis”[MeSH Terms] OR “sialadenitis”[All Fields] OR
                           “sialoadenitis”[All Fields]) AND (“abscess”[MeSH Terms] OR “abscess”[All Fields] OR “abscesses”[All Fields]
                                       OR “abscessation”[All Fields] OR “abscessed”[All Fields] OR “abscessing”[All Fields]))
 Clinicaltrials.gov                      (parotid AND abscess) OR (salivary AND abscess) OR (sialoadenitis AND abscess)                                    5
 Cochrane Library        (parotid AND abscess) OR (salivary AND abscess) OR (sialoadenitis AND abscess) in All Text - (Word variations                     16
                                                                         have been searched)
 Web of Science                 ALL FIELDS: ((parotid AND abscess) OR (salivary AND abscess) OR (sialoadenitis AND abscess))                               338
                             Timespan: All years. Indexes: SCI-EXPANDED, SSCI, A&HCI, CPCI-S, CPCI-SSH, BKCI-S, BKCI-SSH, ESCI,
                                                                         CCR-EXPANDED, IC.
 Embase                    parotid AND (‘abscess’/exp OR abscess) OR (salivary AND (‘abscess’/exp OR abscess)) OR ((‘sialoadenitis’/                       987
                                                        exp OR sialoadenitis) AND (‘abscess’/exp OR abscess))



Levels of evidence were scored according to the Oxford                             The 18 studies had 211 participants with parotid gland ab-
Centre for Evidence-based Medicine (OCEBM) level of                                scesses. Patient numerosity ranged from a 40-patient series
evidence guide 14.                                                                 to a neck abscess case report with a single PA patient. Ten
Search results collection, selections, and data extraction                         articles reported a male to female ratio of included patients,
were performed with the Google Sheets web application                              showing a male sex predominance (99 male patients and
(Google LLC, Mountain View, CA, US).                                               68 female patients). Eight studies were restricted to pae-
A meta-analysis was not performed as originally planned                            diatric patients, while there were no age restrictions in the
due to the heterogeneity of collected data, as detailed in the                     remaining 10. Six studies did not report data on patient age
discussion.                                                                        other than inclusion criteria and 3 had a mixed paediatric-
                                                                                   adult population. When considering articles not restricted
Results                                                                            to paediatric cases, patients were on average in their 4th or
                                                                                   5th decade (6 of 10 papers). Computed tomography and ul-
Among the 1,318 unique research items initially identi-                            trasound were the most common diagnostic modalities, al-
fied, a total of 92 articles were selected for full-text evalu-                    though some studies relied partly or completely on clinical
ation, among which 18 relevant studies published between                           examination only. Magnetic resonance imaging was used
1999 and 2019 were retained for further analysis (Fig. 1).                         sporadically in a few selected cases. All patients were treat-
Except for a single prospective cohort study 9, all articles                       ed with one or more antibiotic therapies, often further tai-
were retrospective case series 2-5,7,15-26. Concerning the level                   lored to results of microbial culture. Most patients (n = 176)
of evidence, 17 studies were rated as level 4 according to                         also underwent abscess incision and drainage, while oth-
the OCEBM scale, and one study was rated as level 2. Ac-                           ers (n = 18) underwent aspiration either with or without
cording to the NHI-SQAT, five articles were rated as good-                         radiological guidance. Eleven patients received antibiotic
quality, 12 articles were rated as fair-quality and one article                    treatment only while the abscess spontaneously ruptured in
was rated to be of poor-quality, respectively. Most lacked                         5 patients. A single patient refused all treatments (includ-
ample information to support the comparability of patients                         ing antibiotic treatment) and died of septic complications.
and/or lacked detailed study endpoints. All articles were                          Eight of 18 studies did not specify the antibiotic regimen
included in the review as no significant methodological                            used. Beta-lactam antibiotics with beta-lactamase inhibi-
bias emerged. As depicted in Figure 2, 7 articles were from                        tors were used in 6 studies and cephalosporins in 5, thus
southern or eastern Asia, 7 from Europe, 3 from northern                           being the most frequently proposed antibiotic treatments.
America, and 1 from Israel. Eight studies focused only on                          Five studies reported adjusting antibiotic therapy to anti-
paediatric patients, while 1 study focused only on melioi-                         biogram results where indicated. Details on antibiotic regi-
dosis cases. Table II reports the characteristics and demo-                        mens are reported in Table III.
graphics of the studies included.                                                  The overall treatment success rate was extremely variable,



108
                                                                                                                                      Treatment for parotid abscess




Figure 1. PRISMA flow diagram of study selection through systematic review.




Figure 2. Geographical representation of the countries of origin of the reviewed articles (in green: one article only; in blue: two or more articles).



                                                                                                                                                             109
A.M. Saibene et al.




Table II. Characteristics of the included studies.
                                        Study      OCEBM             NHI-        NHI-       Country       Treated      Male to          Patient age             Specific
                                         type       rating           SQAT       SQAT                      patients     female             (years)               patient
                                                                     score      rating                      (n)         ratio                                  subgroup
                                                                                                                         (n)                                    studied
 Cheng et al., 2019 4                        CS           4           8/9         G          Taiwan          19         12 M :         Mean 55.5,                 None
                                                                                                                          7F          range 25-88
 Chi et al., 2014 15                         CS           4           7/9          F         Taiwan          14          9M:       Mean 49.6, SD 14.4,            None
                                                                                                                          5F          range 22-75
 Cmejrek et al., 2002 16                     CS           4           5/9          F          US              1          UNS              UNS                 Age < 9 mo
 Daramola et al., 2009 17                    CS           4           6/9          f          US              3           3F          0.17; 0.33; 7              None
 de la Cuesta et al., 2018 18                CS           4           5/9          F         Spain            4          UNS        Mean 2.4, SD 2.4          Aged < 15 y
 Franklyn et al., 2016 7                     CS           4           6/9          F         India           40         28 M :     Mean 46.8, SD 15.8,           None
                                                                                                                         12 F          median 44
 Ganesh and Leese, 2005 5                    CS           4           7/9          F       Singapore         10          3M:           Median 37,                 None
                                                                                                                          7F          range 20-84
 Jaboñska-Jesionowska et al.,                CS           4           5/9          F         Poland           2          UNS              UNS                  Paediatric
 2017 19                                                                                                                                                        patients
 Joo et al, 2017 9                          PCS           2                        F         South            4          UNS                UNS                  None
                                                                                             Korea
 Kim et al., 2018 20                         CS           4           8/9         G          South           13         11 M :      Mean 51, SD 24.3,             None
                                                                                             Korea                       2F            range 7-80
 Lakshmi Narayana et al., 2015 21            CS           4           8/9          F         India            7         6M:          Range 0.67-15            Paediatric
                                                                                                                         1F                                    patients
 Laskawi et al., 2005 22                     CS           4           5/9          F        Germany           5          UNS                UNS               Paediatric
                                                                                                                                                               patients
 Mahawerawat and Kasemsiri, 2018             CS           4           6/9          F        Thailand         22          UNS                UNS               Melioidosis
 23
                                                                                                                                                                cases
 Nusem-Horowitz, 1995 24                     CS           4           4/9         P           Israel          4          UNS                UNS               Paediatric
                                                                                                                                                               patients
 Saarinen et al., 2007 25                    CS           4           8/9         G          Finland         10          5M:            Median 10,            Age <17 y
                                                                                                                         5F           range 2.2-16.8
 Stong et al., 2005 26                       CS           4           5/9          F           US             2          UNS             Mean 6.5,             Paediatric
                                                                                                                                       range 0.5-15             patients
 Tan and Goh, 2006 2                         CS           4           8/9         G         Malaysia         15         10 M :          Median 51,               None
                                                                                                                         5F           range 0.92-77
 Thiede et al., 2002 3                       CS           4           8/9         G         Germany          36         15 M :          Median 44,                None
                                                                                                                         21 F        range 3 mo-79 y
OCEBM: Oxford Centre for Evidence-Based Medicine; NHI-SQAT: National Heart, Lung, and Blood Institute Study Quality Assessment Tools; CS: case series; PCS: prospective cohort
study; F: fair; G: good; P: poor; US: United States of America; M: male; F: female; UNS: unspecified; SD: standard deviation; mo: months. y: years.



ranging from 50% to 100%, though higher and less vari-                                   Fourteen studies reported microbial culture results, which
able in studies with > 10 patients (80-97.2%). The overall                               are detailed in Table IV.
mortality rate was 2.37%, with deaths occurring almost ex-
clusively in extremely compromised patients. Detailed sur-                               Discussion
gical, therapeutic and outcomes for each study are reported
in Table III.                                                                            Our review shows that at present no univocal management
Nine cases of treatment complications were reported (3                                   choices are available for PA and the literature lacks specific
salivary fistulae, 4 facial palsies - one of which was report-                           guidelines or well-designed prospective studies to allow
ed, beyond our review temporal scope, as definitive - and 2                              for evidence-based treatment. This is the first systematic
wound healing problems). Seven of 9 complications were                                   review to address the treatment of PA and confirms the
reported in patients undergoing abscess incision and drain-                              overall good treatment success rates, though not free from
age and 2 in patients with spontaneous abscess rupturing.                                failure and even deaths, especially in more fragile patients.



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Table III. Diagnostic modalities, treatment arms, and outcomes for reviewed studies.
                                 Abscess           Treatment                  Antibiotic treatment                       Outcome               Other
                               diagnostic             arms                                                                                  complications
                               modalities
 Cheng et al., 2019 4         CT (n = 19)        ABx + I&D      Amoxicillin/clavulanate (n = 11), or clindamycin        14/14 cured              None
                                                   (n = 14)         (n = 8) first, antibiogram driven next
                                                 ABx + US-                                                               4/4 cured
                                                    guided
                                                  aspiration
                                                    (n = 4)
                                                 ABx (n = 1)                                                              1/1 died
 Chi et al., 2014 15          CT (n = 14)        ABx + I&D                 UNS broad-spectrum ABx                       14/14 cured         Salivary fistula
                                                  (n = 14)                                                                                      (n = 1)
 Cmejrek et al., 2002 16          UNS            ABx + I&D        UNS empirical ABx first, antibiogram-driven            1/1 cured               None
                                                    (n = 1)                         next
 Daramola et al., 2009 17      CT (n = 3)        ABx + I&D        UNS empirical ABx first, antibiogram-driven            2/2 cured          None reported
                                                    (n = 2)                         next
                                                 ABx (n = 1)                                                              1/1 cured
 de la Cuesta et al.,             UNS            ABx + I&D                         UNS ABx                             2/4 cured, 2/4            None
 2018 18                                            (n = 4)                                                         required another I&D
 Franklyn et al., 2016 7      US (n = 17),       ABx + I&D      Cloxacillin and metronidazole first, antibiogram-    26/30 cured, 4/30           None
                            CT+MRI (n=14),         (n = 30)                       driven next                       required another I&D
                             clinical (n = 9)
                                                    ABx +                                                              2/5 cured, 3/5
                                                  unguided                                                              required I&D
                                               aspiration (n 5)
                                                    ABx in                                                               1/1 cured
                                                spontaneous
                                               rupture (n = 1)
                                                 ABx (n = 3)                                                             3/3 cured
                                                 no therapy                                                               1/1 died
                                                   (n = 1)
 Ganesh and Leese,        CT (n = 9), clinical   ABx + I&D         UNS ABx (most frequently ceftriaxone)            7/8 cured, 1 required        None
 2005 5                          (n = 1)           (n = 8)                                                               another I&D
                                                    ABx in                                                                1/1 cured
                                                spontaneous
                                               rupture (n = 1)
                                                 ABx + CT-                                                               1/1 cured
                                                   guided
                                                  aspiration
                                                   (n = 1)
 Jaboñska-Jesionowska              UNS           ABx + I&D        Amoxiclavulanate or cephalosporin with                 2/2 cured               None
 et al., 2017 19                                   (n = 2)                       clindamycin
 Joo et al., 2017 9        CT + US (n = 4)       ABx + US-                         UNS ABx                               4/4 cured               None
                                                   guided
                                                  aspiration
                                                   (n = 4)
 Kim et al., 2018 20         CT (n = 13)         ABx + I&D                UNS broad-spectrum ABx                       6/7 cured, 1/7            None
                                                   (n = 7)                                                          required another I&D
                                                 ABx (n = 6)                                                              6/6 cured
 Lakshmi Narayana et al.,     US (n = 3),        ABx + I&D      Amoxiclavulanate, changed to clindamycin due              7/7 cured           Temporary
 2015 21                    clinical (n = 4)       (n = 7)            to lack of response in 2 patients                                     marginal branch
                                                                                                                                            palsies (n = 2)
 Laskawi et al., 2005 22          UNS            ABx + I&D              Amoxicillin and/or flucloxacillin                5/5 cured               None
                                                  (n = 5)


                                                                                                                                                               u



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Table III. Diagnostic modalities, treatment arms, and outcomes for reviewed studies (follows).
                                 Abscess           Treatment                  Antibiotic treatment                                     Outcome             Other
                               diagnostic             arms                                                                                              complications
                               modalities
 Mahawerawat and                       UNS              ABx + I&D              Ceftazidime followed by co-trimoxazole             21/22 cured, 1/22          None
 Kasemsiri, 2018 23                                      (n = 22)          (either with or without doxycycline) or amoxi-               died
                                                                                              clavulanate
 Nusem-Horowitz, 1995 24         US (n = 2), US         ABx + I&D                     Penicillin G and cloxacillin                 3/4 healed, 1/4           None
                                after recurrence         (n = 4)                                                                 required another I&D
                                (n = 1), clinical
                                     (n = 1)
 Saarinen et al., 2007 25       US (n = 9), MRI          ABx+ I&D            UNS broad-spectrum ABx (in most cases                     3/3 cured             None
                                     (n = 1)              (n = 3)                metronidazole with penicillin or
                                                                              cefuroxime; clindamycin in one case)
                                                        ABx + US-                                                                   2/4 cured, 2/4           None
                                                          guided                                                                     required I&D
                                                        aspiration
                                                          (n = 4)
                                                          ABx in                                                                       2/3 cured,       Salivary fistula
                                                       spontaneous                                                                    1/3 required          (n = 2)
                                                      rupture (n = 3)                                                               targeted therapy
                                                                                                                                   (mycobacteriosis)
 Stong et al., 2005 26             CT (n = 2)           ABx + I&D                              UNS ABx                                 2/2 cured             None
                                                           (n = 2)
 Tan and Goh, 2006 2              US (n = 5), CT         ABx+ I&D              IV cephalosporins (n=7) IV ampicillin/             12/15 cured, 2/15       1 definitive
                                 (n = 8), clinical      (n = 15, in       clavulanate (n=8), concurrent IV metronidazole          died, 1/15 required   facial paralysis
                                     (n = 2)           one case with       (n=10). Changed to antibiogram driven when                 another I&D        following re-
                                                        underlying                           indicated                                                   exploration, 2
                                                           tumour                                                                                        wounds with
                                                         resection)                                                                                     difficult healing
 Thiede et al., 2002 3            US (n = 34),          ABx + I&D          Amoxiclavulanate unless already prescribed                35/36 cured,          Temporary
                                 US+CT (n=2),             (n = 36)                        prior to I&D                               1/36 required      marginal branch
                                 MRI in selected                                                                                     parotidectomy       palsies (n=1)
                                      (n=?)
CT: computed tomography; UNS: unspecified; US: ultrasound; MRI: magnetic resonance imaging; Abx: antibiotics; I&D: incision and drainage.



The review included a total of 18 studies involving 211                                    choice of antibiotic would allow for adequate drug avail-
patients diagnosed with PA, allowing for a comprehensive                                   ability with conservative treatment 27, leaving incision and
evaluation of the literature. Most of the included studies                                 drainage as a backup option for patients failing first-line
were of good or fair methodological quality. Data were                                     treatment.
almost exclusively retrospectively collected and no ran-                                   Antibiotic regimens therefore become a significant matter
domised controlled trials were found.                                                      of debate for PA treatment. Although cephalosporins and
Treatment success rates overlap between different manage-                                  beta-lactam with beta-lactamase inhibitors remain the most
ment choices, while rates of treatment complication were                                   frequent choice, our systematic review outlined a plethora
unevenly distributed in the three groups studied. No com-                                  of regimens selected with little to no homogeneity often
plications were reported in the 39 patients treated with as-                               providing scarce details on administration, doses and dura-
piration or medical therapy, while 7 of 172 patients treated                               tion. Given that based on the reviewed data S. aureus and S.
with incision and drainage experienced complications, the                                  pneumoniae represent the most frequent cultured bacteria
most frequent being facial nerve damage. Therefore, given                                  in PA, amoxicillin-clavulanate should be regarded as the
the comparable success rates, a different complication rate                                most obvious choice 28, while second-line treatments might
makes aspiration or exclusive medical therapy generally                                    be reserved for non-responders. The specific characteristics
preferable to incision and drainage. Even if this observation                              of each patient (included but not limited to immune status
requires further prospective validation, a more conserva-                                  or prolonged hospitalisation) must be taken into account, as
tive initial approach to PA might seem advisable. A correct                                well as potential drug resistances that can only be assessed



112
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Table IV. Microbiological results (where available) for the included studies.
                                                                                                   Culture yield
 Cheng et al., 2019 4                                                        No yield (n = 6), K. pneumoniae (n = 6), S. aureus (n = 2),
                                                                                       H. influenzae (n = 1), P. micros (n = 1),
                                                                               M. tuberculosis (n = 1), Candida parapsilosis (n = 1),
                                                                                              Salmonella Group D (n = 1)
 Chi et al., 2014 15                                    No yield (n = 6), K. pneumoniae (n = 4), F. magna (n = 1), H. influenzae (n = 1), S. aureus (n = 2)
 Franklyn et al., 2016 7                             No yield (n = 3), S. aureus (n = 10), Klebisiella spp. (n = 6), B-haemolytic Streptococcus spp. (n = 4),
                                                   non-haemolytic Streptococcus spp. (n = ), Enterococcus spp (n = 2), Proteus spp. (n = 1), E. coli (n = 1),
                                                                                 Enterobacter spp. (n = 1), M. tuberculosis (n = 2)
 Ganesh and Leese, 2005 5                         No yield (n = 5), S. aureus (n = 2), K. pneumoniae (n = 1), E. coli (n = 1), A-haemolytic Streptococcus spp.
                                                                                                       (n = 1)
 Jaboñska-Jesionowska et al., 2017 19                                                             S. aureus (n = 2)
 Kim et al., 2018 20                                  No yield (n = 5), P. aeruginosa (n = 1), P. intermedia (n = 1), S. epidermidis (n = 1); P. acnes (n = 1)
 Lakshmi Narayana et al., 2015 21                            No yield (n = 2), MSSA (n = 3), B-Haemolytic Streptococcus spp. (n = 1), E. coli (n = 1)
 Laskawi et al, 2005 22                                                                           S. aureus (n = 5)
 Mahawerawat and Kasemsiri, 2018 23                                                           B. pseudomallei (n = 22)
 Nusem-Horowitz, 1995 24                               No yield (n = 1), Gram-negative cocci (n = 1), coagulase negative Staphylococci (n = 1), anaerobic
                                                                                                 Streptococci (n = 1)
 Saarinen et al., 2007 25                           No yield (n=3), H. Influenzae (n = 3), S. pneumoniae (n = 1), P. mirabilis (n = 1), M. tuberculosis (n = 1)
 Stong et al., 2005 26                                                                 S. Viridans (n = 1), S. aureus (n = 1)
 Tan and Goh, 2006 2                             No yield (n = 5), S. aureus (n = 2), MRSA (n = 1), S. milieri (n = 1), S. pyogenes (n = 1), Klebsiella spp (n = 3),
                                                                               Psuedomonas spp. (n = 1), Haemophilus spp. (n = 1)
 Thiede et al., 2002 3                             No yield (n = 10), S. aureus (n = 9), S. epidermidis (n = 1), Streptococcu spp. (n = 5), Peptostreptococcus
                                                                        spp. (n = 4), M. tuberculosis (n = 2), atypical mycobacteria (n = 2)



by antibiograms performed on collections from incision                              therapeutic choices and outcomes, we were unable to sys-
and drainage and aspiration.                                                        tematically explore their role, as these important features
Lastly, our data show a low prevalence of anaerobic bacte-                          are reported inconsistently and sporadically in the reviewed
ria, which may be nevertheless due to inadequate collection                         articles. This heterogeneity made the initially planned me-
methods. A more thorough investigation of PA microbiol-                             ta-analysis potentially misleading. Important variables for
ogy and drug susceptibility represents a future challenge                           making a decision in terms of management, such as the lo-
for clinicians.                                                                     cation of the abscess (superficial or deep lobe), the volume
Our data geographical breakdown points towards a strong                             of the collection, risk of fistulisation or septicaemic com-
research interest in PA in eastern Asia, possibly mirroring                         plications, are required both to compare different studies
a higher local incidence of PA. This could be either due to                         and to question the drainage timing.
the local distribution of specific pathogens such as B. pseu-                       Data collected in our review did not allow to allocate pa-
domallei or to tropical climate as a facilitating factor in the                     tients to an adult or paediatric population in 7 of 18 arti-
development of PA 23.                                                               cles and often allowed a wide age range to the paediatric
Our study has two significant limitations. First of all, the                        population thus making assumptions on the validity of our
small number of patients included is reflected by underpow-                         data in a specific age group impossible. Therefore, future
ered results, especially for what concerns aspiration and                           prospective studies should also separately take into account
exclusive medical management. Conversely, the inclusion                             paediatric and adult patients, given the inherent treatment
of wide-focus case series with a single or few PA patients,                         differences between the two groups in terms of compli-
while providing a comprehensive evaluation of the litera-                           ance to therapy and invasive procedures 29. On a side note,
ture, introduces a potential reporting bias. Secondly, we                           this review does not cover the role of steroid drugs, which
encountered a significant heterogeneity in patient samples                          have been shown to offer some symptomatic relief in other
and medical therapies. Although we are aware that some                              head and neck abscesses 30. Given the far less benignant
patient-/disease-specific characteristics such as abscess                           course of PA compared to peritonsillar abscesses, the role
size, superficial versus deep lobe location, facial nerve                           of corticosteroids should be explored also with regards to
involvement, co-existing sepsis, immune status influence                            prognosis.



                                                                                                                                                               113
A.M. Saibene et al.




Lastly, we chose to exclude from this review articles fo-                    4
                                                                                  Cheng L-H, Wang H-W, Lin C-M, et al. Parotid abscess: 15-year
                                                                                  experience at a tertiary care referral center in Taiwan. J Med Sci
cusing only on mycobacterial abscess as they tend to have
                                                                                  2019;39:231-235. https://doi.org/10.4103/jmedsci.jmedsci_15_19
a slightly different clinical course and management31, and                   5
                                                                                  Ganesh R, Leese T. Parotid abscess in Singapore. Singapore Med J
thus the conclusions drawn from our analysis might not ex-                        2005;46:553-556.
tend to this patient population.                                             6
                                                                                  Brook I. The bacteriology of salivary gland infections. Oral Maxil-
                                                                                  lofac Surg Clin North Am 2009;21:269-274. https://doi.org/10.1016/j.
                                                                                  coms.2009.05.001
Conclusions                                                                  7
                                                                                  Franklyn J, Gaikwad P, Lazarus E, et al. Parotid abscess: a clinical
Our findings suggest that antibiotics are the mainstay of                         analysis of 40 cases in a tertiary care hospital in India. J Oral Maxil-
                                                                                  lofac Surg Med Path 2017;29:189-192.
PA treatment, with excellent success rates, while the ex-                    8
                                                                                  Dabirmoghaddam P, Mohseni A, Navvabi Z, et al. Is ultrasonography-
act role for incision and drainage and aspiration should be                       guided drainage a safe and effective alternative to incision and drainage
further explored in adequately designed prospective stud-                         for deep neck space abscesses? J Laryngol Otol 2017;131:259-263.
ies. Given the higher (albeit still small) proportion of treat-                   https://doi.org/10.1017/s002221511700007x
ment complications in the incision and drainage group,
                                                                             9
                                                                                  Joo BY, Jang AL, Lee JH, et al. Application of ultrasound-guided
                                                                                  pigtail catheter drainage for abscesses in the head and neck. Clin
a more conservative yet watchful approach towards PA                              Otolaryngol 2017;42:1087-1091. https://doi.org/10.1111/coa.12864
might be advisable, but we are at present unable to define                   10
                                                                                  Biron VL, Kurien G, Dziegielewski P, et al. Surgical vs ultrasound-
evidence-based strategies. Furthermore, incision and drain-                       guided drainage of deep neck space abscesses: a randomized
age emerged as a preferential management choice for man-                          controlled trial: surgical vs ultrasound drainage. J Otolaryngol Head
                                                                                  Neck Surg 2013;42:18. https://doi.org/10.1186/1916-0216-42-18
agement failures independently of the original therapeutic                   11
                                                                                  Hassan A, Gaafar A. Surgical versus ultrasound guided aspiration
choice. Therefore, incision and drainage might be recom-                          or drainage of deep neck space abscesses: a randomized controlled
mended as a salvage option for PA in the case of failure of                       trial. ALEXMED ePosters 2021;3:18-19. https://doi.org/10.21608/
aspiration or exclusive medical therapy.                                          ALEXPO.2021.57390.1111
                                                                             12
                                                                                  Liberati A, Altman DG, Tetzlaff J, et al. The PRISMA statement
Conflict of interest statement                                                    for reporting systematic reviews and meta-analyses of studies that
                                                                                  evaluate healthcare interventions: explanation and elaboration. BMJ
The authors declare no conflict of interest.                                      2009;339:b2700. https://doi.org/10.1136/bmj.b2700
                                                                             13
                                                                                  National Heart, Lung, and Blood Institute (NHLBI). Study Quality
Funding                                                                           Assessment Tools. https://www.nhlbi.nih.gov/health-topics/study-
This research did not receive any specific grant from fund-                       quality-assessment-tools. Accessed January 10, 2021.
ing agencies in the public, commercial, or not-for-profit
                                                                             14
                                                                                  Oxford Centre for Evidence-Based Medicine. The Oxford Levels of
                                                                                  Evidence 2. https://www.cebm.net/index.aspx?o=5653. Accessed
sectors.                                                                          January 10, 2021.
                                                                             15
                                                                                  Chi TH, Yuan CH, Chen HS. Parotid abscess: a retrospective study of
Authors’ contributions                                                            14 cases at a regional hospital in Taiwan. B-ENT 2014;10:315-318.
AMS and FA: study design, article search and selection,                      16
                                                                                  Cmejrek RC, Coticchia JM, Arnold JE. Presentation, diagnosis,
data extraction. TA, JRL, MM-Y and KP: drafting of the                            and management of deep-neck abscesses in infants. Arch Otolaryn-
                                                                                  gol Head Neck Surg 2002;128:1361-1364. https://doi.org/10.1001/
article. CMC-E: study design and critical revision of the                         archotol.128.12.1361
article.                                                                     17
                                                                                  Daramola OO, Flanagan CE, Maisel RH, et al. Diagnosis and treat-
                                                                                  ment of deep neck space abscesses. Otolaryngol Head Neck Surg
Ethical consideration                                                             2009;141:123-130. https://doi.org/10.1016/j.otohns.2009.03.033
No formal ethics committee approval was required for this                    18
                                                                                  de la Cuesta FR, Cortes CE, Me GR, et al. [Deep neck space ab-
                                                                                  scesses in children: 15 years of experience in a children’s ENT re-
article as it is based on already published clinical data from
                                                                                  ferral unit]. An Pediatr 2019;91:30-36. https://doi.org/10.1016/j.
other studies available in the literature.                                        anpedi.2018.09.014
                                                                             19
                                                                                  Jabłońska-Jesionowska M, Dębska-Rutkowska M, Kwast P, et al.
                                                                                  Parotitis in children hospitalized in the Department of Pediatric
References                                                                        Otolaryngology of the Medical University of Warsaw in the years
1
    Carbone PN, Capra GG, Brigger MT. Antibiotic therapy for pediatric            2010-2017. New Med 2017;21:99-107. http://doi.org/10.25121/
    deep neck abscesses: a systematic review. Int J Pediatr Otorhinolaryn-        NewMed.2017.21.4.99
    gol 2012;76:1647-1653. https://doi.org/10.1016/j.ijporl.2012.07.038      20
                                                                                  Kim YY, Lee DH, Yoon TM, et al. Parotid abscess at a single institute
2
    Tan VE, Goh BS. Parotid abscess: a five-year review - clinical pres-          in Korea. Medicine 2018;97:e11700. https://doi.org/10.1097/
    entation, diagnosis and management. J Laryngol Otol 2007;121:872-             md.0000000000011700
    879. https://doi.org/10.1017/s0022215106004166                           21
                                                                                  Lakshmi Narayana M, Azeem Mohiyuddin SM, Mohammadi K,
3
    Thiede O, Stoll W, Schmäl F. Clinical aspects of abscess develop-             et al. Parotid abscess in children - A tertiary rural hospital experi-
    ment in parotitis. HNO 2002;50:332-338. https://doi.org/10.1007/              ence. Int J Pediatr Otorhinolaryngol 2015;79:1988-1990. https://doi.
    s001060100544                                                                 org/10.1016/j.ijporl.2015.10.021




114
                                                                                                                               Treatment for parotid abscess




22
     Laskawi R, Schaffranietz F, Arglebe C, et al. Inflammatory dis-            27
                                                                                     Wagner C, Sauermann R, Joukhadar C. Principles of antibiotic pen-
     eases of the salivary glands in infants and adolescents. Int J Pedi-            etration into abscess fluid. Pharmacology 2006;78:1-10. https://doi.
     atr Otorhinolaryngol 2006;70:129-136. https://doi.org/10.1016/j.                org/10.1159/000094668
     ijporl.2005.06.012                                                         28
                                                                                     Sader HS, Jacobs MR, Fritsche TR. Review of the spectrum and
23
     Mahawerawat K, Kasemsiri P. Clinical presentation and treat-                    potency of orally administered cephalosporins and amoxicillin/cla-
     ment of melioidosis in the head and neck region. J Laryngol Otol                vulanate. Diagn Microbiol Infect Dis 2007;57:5S-12S. https://doi.
     2018;132:827-831. https://doi.org/10.1017/s0022215118001391                     org/10.1016/j.diagmicrobio.2006.12.014
24
     Nusem-Horowitz S, Wolf M, Coret A, et al. Acute suppurative paro-          29
                                                                                     Blitz M, Britton KC. Management of the uncooperative child.
     titis and parotid abscess in children. Int J Pediatr Otorhinolaryngol           Oral Maxillofac Surg Clin North Am 2010;22:461-469. https://doi.
     1995;32:12-127. https://doi.org/10.1016/0165-5876(94)01120-m                    org/10.1016/j.coms.2010.08.002
25
     Saarinen RT, Kolho KL, Pitkäranta A. Cases presenting as parotid ab-       30
                                                                                     Lee YJ, Jeong YM, Lee HS, et al. The efficacy of corticosteroids in the
     scesses in children. Int J Pediatr Otorhinolaryngol 2007;71:897-901.            treatment of peritonsillar abscess: a meta-analysis. Clin Exp Otorhi-
     https://doi.org/10.1016/j.ijporl.2007.02.011                                    nolaryngol 2016;9:89-97. https://doi.org/10.21053/ceo.2014.01851
26
     Stong BC, Sipp JA, Sobol SE. Pediatric parotitis: a 5-year review          31
                                                                                     Chaudhary P, Chaudhary B, Munjewar CK. Parotid tuberculo-
     at a tertiary care pediatric institution. Int J Pediatr Otorhinolaryngol        sis. Indian J Tuberc 2017;64:161-166. https://doi.org/10.1016/j.
     2006;70:541-544. https://doi.org/10.1016/j.ijporl.2005.08.001                   ijtb.2017.03.004




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