10.5826/dpc.1302a169
text/xml
2160-9381
3018
en
Pawel  Pietkiewicz
https://creativecommons.org/licenses/by-nc/4.0
Dermatology Practical & Conceptual
corynebacteria
Ultraviolet Reflectance Dermatoscopy of Trichobacteriosis Axillaris Reveals Peripilar Yellow-Green Luminescent Concretions
Text.Serial.Journal
https://dpcj.org/index.php/dpc
Research Letter
2023-04-29
2022-11-23
2023-04-29
2023-06-05
e2023169
Dermatol Pract Concept
Pawel  Pietkiewicz
2023/04/29
10.5826/dpc.1302a169
e2023169
Polish Dermatoscopy Group, Poznań, Poland
2160-9381
corynebacteria
en
e2023169
Mojeski JA, Almashali M, Jowdy P, et al. Ultraviolet imaging in dermatology. Photodiagnosis Photodyn Ther. 2020;30:101743. DOI: 10.1016/j.pdpdt.2020.101743. PMID: 32198019.
Ultraviolet Reflectance Dermatoscopy of Trichobacteriosis Axillaris Reveals Peripilar Yellow-Green Luminescent Concretions
https://dpcj.org/index.php/dpc/article/download/3018/1983
 Ultraviolet-Induced Fluorescence Dermatoscopy of
     Trichobacteriosis Axillaris Reveals Peripilar
       Yellow-Green Luminescent Concretions
              Marwan Al-Nasiri1, Cristian Navarrete-Dechent2,3, Katarzyna Korecka4,5,
                 Natalia Salwowska5,6, Mohamad Goldust7, Paweł Pietkiewicz5,8


1 St. Michael’s Clinic, Shrewsbury, United Kingdom
2 Department of Dermatology, Escuela de Medicina, Pontificia Universidad Católica de Chile, Santiago, Chile
3 Melanoma and Skin Cancer Unit, Escuela de Medicina, Pontificia Universidad Católica de Chile, Santiago, Chile
4 Department of Skin Diseases, Regional Hospital, Poznań, Poland
5 Polish Dermatoscopy Group, Poznań, Poland
6 Department of Dermatology, School of Medicine, Medical University of Silesia, Katowice, Poland
7 Department of Dermatology, Yale School of Medicine, Yale University, New Haven, Connecticut, USA
8 Dermatology Private Practice, Poznań, Poland



Key words: dermatoscopy, corynebacteria, trichomycosis, ultraviolet radiation, imaging
Citation: Al-Nasiri M, Navarrete-Dechent C, Korecka K, Salwowska N, Goldust M, Pietkiewicz P. Ultraviolet-Induced Fluorescence
Dermatoscopy of Trichobacteriosis Axillaris Reveals Peripilar Yellow-Green Luminescent Concretions. Dermatol Pract Concept.
2023;13(2):e2023169. DOI: https://doi.org/10.5826/dpc.1302a169
Accepted: February 4, 2023; Published: April 2023
Copyright: ©2023 Al-Nasiri et al. This is an open-access article distributed under the terms of the Creative Commons Attribution-
NonCommercial License (BY-NC-4.0), https://creativecommons.org/licenses/by-nc/4.0/, which permits unrestricted noncommercial use,
distribution, and reproduction in any medium, provided the original authors and source are credited.
Funding: None.
Competing interests: None.
Authorship: All authors have contributed significantly to this publication.
Corresponding author: Paweł Pietkiewicz, Centrum Medyczne Zwierzyniecka, Zwierzyniecka Street 30/28, Poznań 60-814.
Telephone: +48 602 133 503 Email: pietkiewicz.pp@gmail.com




Introduction                                                             have been cultured from rare red variant, and Micrococus
                                                                         nigricans from the rare black concretions [1]. The disorder
Trichobacteriosis axillaris (TA) is a superficial bacterial in-          is more common in tropical and humid climates, and usually
fection caused by Corynebacterium species that commonly                  affects teenagers and young adults. TA can be differentiated
affect the soft keratin layer around the axillary hair and, to a         from piedra, pediculosis, hair casts and Trichosporon aselie
lesser extent, pubic, genital, and rarely scalp hair [1]. In most        infections with Wood’s lamp (peak wavelength 365 nm) [1,2].
cases, the diagnosis is supported by the patient’s history of            However, when atypical hair bearing areas are affected,
smelly/sweaty armpits, in addition to the most common clini-             dermatoscopy can serve as a helpful diagnostic aid by
cal appearance of irregular yellow cement-like insoluble con-            demonstrating these typical yellow concretions [3]. Ultravi-
cretions wrapped around the hair shaft predominantly caused              olet-induced fluorescence dermatoscopy (UVFD), a novel di-
by Corynebacterium flavescens. Micrococcus castelani or                  agnostic technique, can evoke neon-like “UV fluorescence”.
co-infection of Corynebacterium sp. and Serratia mascescens              The chemical compound excited with UV irradiation emits



Research Letter | Dermatol Pract Concept. 2023;13(2):e2023169                                                                       1
    Figure 1. Trichobacteriosis axillaris. (A) Clinical presentation with creamy whitish segmentally “thickened” hair of the axilla.
    (B) Non-contact polarized dermatoscopy showing yellowish-whitish bacterial conglomerates wrapping the hair. (C) Non-contact ul-
    traviolet-induced fluorescence dermatoscopy featuring prominent yellowish-greenish luminescence confirming the diagnosis. (Xiaomi
    Mi 10T Pro 5G, Xiaomi, paired with DL5, Dermlite; ×10 magnification).




new (usually longer) wavelength, that can belong to the vis-          diagnoses that do not exhibit this unique feature. Therefore,
ible light spectrum [4]. To the best of our knowledge, our            no cost-incurring and time-consuming investigations are re-
report is the first report on the use of UVFD in TA.                  quired. The exact source of the yellow-green luminescence
                                                                      has not been identified yet, but it is hypothesized to originate
                                                                      from the admixture of the sweat and bacterial products. The
Case Presentation                                                     utilization of UVFD, initially used for tumor margin delinea-
A 62-year-old Caucasian male presented for a routine skin             tion in melanoma, is expected to be further utilized in the di-
check. The clinical examination of the axillary hair r­ evealed       agnosis of multiple neoplastic, inflammatory, and infectious
asymptomatic thin irregular creamy yellow concretions en-             conditions of the skin and adnexa.
circling several hair shafts (Figure 1A). The detail of these
concretions was more recognizable in adequate lighting
and close up imaging (Figure 1B). In this case, additional            References
non-contact UVFD (DL5, Dermlite; ×10 magnification)                    1. Bonifaz A, Váquez-González D, Fierro L, Araiza J, Ponce RM.
showed distinctive bright yellow-green excited luminescence               Trichomycosis (trichobacteriosis): clinical and microbiological
(Figure 1C), which enabled a spot diagnosis of TA. The                    experience with 56 cases. Int J Trichology. 2013;5(1):12-16.
­patient was advised to shave axillary hair, treated with 2%              DOI: 10.4103/0974-7753.114704. PMID: 23960390. PMCID:
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topical fucidic acid, and discharged without further testing.
                                                                       2. Dyer JM, Foy VM. Revealing The Unseen: A Review of
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                                                                          of dermoscopy and why it should always be done. J Eur Acad
However, diagnostic difficulties arise in atypical clinical
                                                                          Dermatol Venereol. 2017;31(6):e275-e276. DOI: 10.1111/jdv
presentations or atypical locations [3]. UVFD can be used
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to further increase the diagnostic confidence by visualizing           4. Mojeski JA, Almashali M, Jowdy P, et al. Ultraviolet imaging in
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shafts. This adequately rules out other clinical differential             DOI: 10.1016/j.pdpdt.2020.101743. PMID: 32198019.




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