10.5826/dpc.1203a98
text/xml
2160-9381
2003
en
Cesare  Filippeschi
https://creativecommons.org/licenses/by-nc/4.0
Dermatology Practical & Conceptual
resistance
Butterfly sign in scabies: towards an evolutionary process?
Text.Serial.Journal
https://dpcj.org/index.php/dpc
Research Letter
2022-07-28
2021-08-31
2022-07-28
2022-09-15
e2022098
Dermatol Pract Concept
Cesare  Filippeschi
2022/07/28
10.5826/dpc.1203a98
e2022098
Dermatology Unit, Department of Pediatrics, Meyer Children's University Hospital, Florence, Italy
2160-9381
resistance
en
e2022098
Butterfly sign in scabies: towards an evolutionary process?
https://dpcj.org/index.php/dpc/article/download/2003/1661
                    Dermatology Practical & Conceptual


                        Butterfly Sign in Scabies: Towards
                            an Evolutionary Process?
                         Teresa Oranges1, Fausto Andrea Pedaci2, Cesare Filippeschi1


1 Dermatology Unit, Department of Pediatrics, Meyer Children's Hospital, Florence, Italy.
2 Department of Health Sciences, Meyer Children’s Hospital, Florence, Italy.



Key words: scabies, sarcoptes scabiei hominis, dermoscopy, dermatoscopy, resistance
Citation: Oranges T, Pedaci FA, Filippeschi C. Butterfly sign in scabies: towards an evolutionary process?
Dermatol Pract Concept. 2022;12(3):e2022098. DOI: https://doi.org/10.5826/dpc.1203a98
Accepted: October 25, 2021; Published: July 2022
Copyright: ©2022 Oranges et al. This is an open-access article distributed under the terms of the Creative Commons Attribution
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: Teresa Oranges, MD, PhD, Department of Pediatrics, Dermatology Unit, Meyer Children's Hospital, Viale Gaetano
Pieraccini 24, 50139, Florence, Italy Tel +39 0555662944 E-mail: teresa.oranges@gmail.com




Introduction
Human scabies is a worldwide skin infestation caused
by the mite Sarcoptes scabiei hominis and remains a sig-
nificant public health concern. The detection of the mite
is essential for diagnosis and entodermoscopy strongly
improves diagnostic reliability. The mite is visible on der-
moscopy at the head of the burrow, due to its refractile
area located between the buccal apparatus and the second
pair of legs. This sign is called “triangle” sign or “delta
glider” sign, or “hang glider” sign (Figure 1A, asterisk)
[1]. The “triangle” sign is usually accompanied by reflect-
ing bubbles along the tunnel called “jet trail” sign on wet
dermoscopy (Figure 1A, arrow) [1]. Other less frequently
observed dermoscopic signs have been described and one
of the most recently described feature is the “gray-edge                 Figure 1. (A) Dermoscopy of a scabies burrow showing the “delta
line” sign, that it’s due to the presence of mite feces con-             glider” sign (asterisk), reflective bubbles within the burrow referred
                                                                         to as “jet trail” sign (arrow) and blackish-gray lines at some points
taining melanin (Figure 1A, arrowhead) [1]. We present
                                                                         of the burrow walls consistent to the “gray-edge line” sign (arrow-
a new dermoscopic sign observed in 2 cases, in the era                   head). (B) Microscopic examination of a Sarcoptes scabiei hominis
of progressive resistance of Sarcoptes scabiei hominis to                with classical features: the gut area appears poorly demarcated and
standard treatments.                                                     of the same color of the adjacent structures (arrow).



Research Letter | Dermatol Pract Concept. 2022;12(3):e2022098                                                                                1
    Figure 2. Dermoscopic evaluation of a scabies burrow of the 5-years old patient (A) and of the 10-years old patient (C) with the
    corresponding microscopic appearance of the scraped mites (B and D). (A-C) Both dermoscopic images show the “delta glider” sign
    (asterisks) and the presence, just below, of a reddish structure corresponding to the “butterfly” sign (arrows). (B-D) Microscopic
    features of the anterior part of the mite body (asterisks) and of the underlying gut area which appear well demarcated and reddish
    in color (arrows).




Case presentation                                                      sign (Figure 2, A-C, arrow). The microscopic examination
                                                                       of the scraped skin in correspondence to the burrow showed
We observed 2 cases of young patients (a 10-year-old male              in both patients the presence of the mite with a well-defined
and a 5-year-old male) referred to the dermatologic unit for           butterfly-shaped gut area, with a reddish coloration resem-
scabies present for several months, treated with multiple cy-          bling blood (Figure 2, B-D, arrow). Of note, the gut area of
cles of permethrin 5% cream. Physical examination revealed             the Sarcoptes scabiei hominis mite is usually not so clearly
persistent multiple mite burrows with classic dermoscopic              visible under the microscope (Figure 1B, arrow).
image of “delta glider” sign (Figure 2, A-C, asterisk), cor-
responding to the anterior part of the mite (Figure 2,                 Conclusions
B-D, asterisk), associated with a new dermoscopic sign,
which we called the “butterfly” sign, characterized by a               Recently, several authors described the emerging phenome-
butterfly-shaped reddish area just below the “delta glider”            non of resistance of mites to standard treatments, in particular



2                                                                          Research Letter | Dermatol Pract Concept. 2022;12(3):e2022098
to permethrin, as in our cases [2]. Considering these recent          2. Mazzatenta C, Piccolo V, Argenziano G, Bassi A. Is Scabies be-
evidences, this report suggests a new dermoscopic sign as a              coming less sensitive to permethrin therapy? J Eur Acad Derma-
                                                                         tol Venereol. 2021;35(9):e607-e609. DOI: 10.1111/jdv.17339.
possible marker of Sarcoptes scabiei hominis evolution.
                                                                         PMID: 33974300.


References
 1. Ueda T, Katsura Y, Sasaki A, Minagawa D, Amoh Y, Shirai K.
    Gray-edged line sign of scabies burrow. J Dermatol. 2021;48(2):
    190-198. DOI: https://doi.org/10.1111/1346-8138.15650. PMID:
    33063894.




Research Letter | Dermatol Pract Concept. 2022;12(3):e2022098                                                                        3
