Digital dermoscopy: a complementary method in the diagnosis of scabies,

AnBrasDermatol.2020;95(5):638---640

Anais

Brasileiros

de

Dermatologia

TROPICAL/INFECTOPARASITARY

DERMATOLOGY

Digital

dermoscopy:

a

complementary

method

in

the

diagnosis

of

scabies

夽,夽夽

Elaine

Dias

Melo

_,

_Carla

_Barros

_da

_Rocha

_Ribas

_,

Isabel

Cristina

Lima

Encarnac

¸ão

a_{TeachingandResearchDepartment,Fundac¸ãodeDermatologiaTropicaleVenereologiaAlfredodaMatta,Manaus,AM,Brazil} b_{PediatricDermatologyClinic,Fundac¸ãodeDermatologiaTropicaleVenereologiaAlfredodaMatta,Manaus,AM,Brazil}

Received9August2019;accepted30November2019 Availableonline26June2020

KEYWORDS

Dermoscopy; Diagnosisbyimage; Scabies

Abstract Scabiesisanectoparasitosis causedby Sarcoptes scabieivar. hominis,

characte-rizedclinicallybypruriticlesionsintypicallocations;thecrustedformisararemanifestation. Thediagnosisisusuallyestablishedbasedontheclinicalpicture, butdermoscopycanbean importantcomplementarymethod,asitallowstheobservationofabrownishtriangular struc-turewithahang-gliderappearance.Acaseofcrustedscabiesisreported; themagnification oftheimagesobtainedbydigitaldermoscopyallowedthedemonstrationofastructureusually observedonlywithvideodermoscopy.

©2020SociedadeBrasileiradeDermatologia.PublishedbyElsevierEspa˜na,S.L.U.Thisisan openaccessarticleundertheCCBYlicense(http://creativecommons.org/licenses/by/4.0/).

ScabiesisanectoparasitosiscausedbythemiteSarcoptes scabiei var. hominis, whose transmission occurs through interpersonalcontactand occasionallythrough fomites.1,2

Clinically,it is characterized by erythematouspapules or vesicles and tunnels located in the interdigital spaces, flexorsurfacesofthewrists,umbilicalregion,andflexural areas.1

夽 _{Howtocitethisarticle:MeloED,RibasCBR,Encarnac¸ãoICL.}

Digitaldermoscopy:acomplementarymethodinthediagnosisof

scabies.AnBrasDermatol.2020;95:638---40.

夽夽_{StudyconductedattheFundac¸ãodeDermatologiaTropicale}

VenereologiaAlfredodaMatta,Manaus,AM,Brasil.

∗_{Correspondingauthor.}

E-mail:e.dmelo@yahoo.com(E.D.Melo).

The crusted form is considered a rare presentation; immunodepression and mental and/or motor deficits are the main risk factors.3 _{It manifests with hyperkeratotic,}

fissured, crusted, or erythrodermic lesions, variable pru-ritus, and the presence of millionsof mites, being highly contagious.1,4

The diagnosis is usually established basedon the clin-icalpicture, but itcan be complementedby dermoscopy, videodermoscopy,orconfocalmicroscopy,andisconfirmed bydirectexaminationorbiopsy.1,2_{Theauthorsreportacase}

ofcrustedscabieswithanemphasisondermoscopicfindings. Afemalepatient,29yearsofage,nativeBrazilian, pre-sentedwitherythematouspapulesandlichenifiedplaques, some of which were hyperkeratotic, in the acral, flexu-ral, and abdominal regions, associated withmild pruritus foreightmonths(Fig.1).Dermoscopywasperformedwith https://doi.org/10.1016/j.abd.2019.11.014

0365-0596/©2020SociedadeBrasileiradeDermatologia.PublishedbyElsevierEspa˜na,S.L.U.ThisisanopenaccessarticleundertheCC

Digitaldermoscopy:acomplementarymethodinthediagnosisofscabies 639

Figure1 Erythematouspapulesandlichenifiedplaques,somehyperkeratotic,locatedmainlyonthelimbs,flexuralareas(A),

andabdomen(B).

immersion,underpolarizedlight(10×,DermLiteDL4, Cal-ifornia, UnitedStates)ofan unscathedlesiononthearm, andtheimageswerecapturedwithacamera(12Mp,iPhone 7, Apple Inc., California, United States) with 2× optical zoomallowingthe observationofthemillipede-like struc-turesandthehang-gliderappearance(Fig.2).Subsequently, image amplification demonstrated a translucent rounded structure (Fig.3).Directexamination confirmedthe diag-nosisof crustedscabies(Fig.4)and,aftertreatment, the patientevolvedwithresolutionofthelesions.5

Dermoscopyhasbeenwidelyreportedinrecentyearsas an aid in the diagnosis of scabies. It allows the observa-tionof a brownish triangular structure witha hang-glider appearance, corresponding tothe anterior portionof the bodyandthefrontlegsofthemite,andatunnel,whichcan assumeamillipede-likeconformation.6 _{Incrustedscabies,}

theliteraturefeaturesreportsofatunnel-over-tunnel pat-tern,describedasanoodlepattern,whichcorrespondsto tunnelsdugbyvariousparasites.7

Observation of the mite’sbody is reportedwhen using videodermoscopy.2,8 _{In2016, Cinotti etal. compared20×}

and70×magnifications,andonlysawthebodyofthemite inthelatter.9

Figure 2 Demonstration of the structures: (i) hang-glider:

anterior portion ofthe body and front legs of themite; (ii) millipede-like:scabiestunnel; (iii)roundedtranslucent: mite body.(Digitaldermoscopy,×10withimmersion,underpolarized lightandopticalzoom,×2.)

However, in 2019, Scanni demonstrated this structure through digital dermoscopy, defined as acquisition and storage of imagesobtained by dermoscopy.10 _{That author}

associated dermoscopy (10×), optical zoom of the cam-era (3---5×), and image amplification, and demonstrated some structures that make up what he defined as ‘‘the mite-galleryunit.’’10 _{Thisunitconsistsofthehead,which}

correspondstothemitewiththehang-gliderstructure,the body,which containsthe tunnelwitheggs andfeces,and thetail,theendofthetunnelcomposedofkeratincollars, viewedonlywithdermoscopywithout immersion.Through imageamplification,thetranslucentbodyofthemitewith severalscattereddarkspots(termedladybirdsign)canalso beobserved.10 _{Inthepresent report,usingthistechnique,}

itwaspossibletodemonstratethehang-gliderappearance, theovoidbody,andthetunnel.

Itisknownthattheobservationofthemitebody,eggs, and feces is the best with videodermoscopy.2,8 _However,

when unavailable,the use of the technique described by Scanniandappliedinthepresentreportcanallowamore accuratediagnosisofscabies.

Figure 3 Demonstration ofthe structures: (i) hang-glider:

anteriorportion of the body andfront legs ofthe mite; (ii) millipede-like:scabiestunnel;(iii) roundedtranslucent:mite body.(Digitaldermoscopy,×10withimmersion,underpolarized light,opticalzoom,×2,andimageamplification.)

640 MeloEDetal.

Figure4 Observationofthemite(a)andeggs(b)inthedirectexamination(KOH20%,×100).

Financial

support

Nonedeclared.

Authors’

contributions

Elaine Dias Melo: Conception and planning of the study; elaborationandwritingofthemanuscript;obtaining, ana-lyzing,andinterpretingthedata;intellectualparticipation in propaedeutic and/or therapeutic conduct of studied cases;criticalreviewoftheliterature.

Carla BarrosdaRochaRibas:Approvalof the final ver-sion of the manuscript; elaboration and writing of the manuscript;effectiveparticipationinresearchorientation; intellectual participation in propaedeutic and/or thera-peutic conduct of studied cases; critical review of the manuscript.

IsabelCristinaLimaIncarnation:Approvalofthefinal ver-sionofthemanuscript;effectiveparticipationin research orientation; intellectual participation in propaedeutic and/ortherapeuticconductofstudiedcases;criticalreview ofthemanuscript.

Conflicts

of

interest

Nonedeclared.

Acknowledgements

To Dr. Patrícia Motta de Morais, dermatopathologist, who assistedinthephotographicrecordofthedirect examina-tion.

References

1.Sánchez-Borges M, González-Aveledo L, Capriles-Hulett A, Caballero-FonsecaF.Scabies,crusted(Norwegian)scabiesand the diagnosis of mite sensitisation. Allergol Immunopathol (Madr).2018;46:276---80.

2.MicaliG, LacarrubbaF,Verzì AE,Chosidow O, Schwartz RA. Scabies:advancesinnoninvasivediagnosis.PLoSNeglTropDis. 2016;10:e0004691.

3.Jouret G, Bounemeur R, Presle A, Takin R. La gale hyper-kératosique.AnnDermatolVenereol.2016;143:251---6.

4.DavisJS,McGloughlinS,TongSY,WaltonSF,CurrieBJ.Anovel clinicalgradingscaletoguidethemanagementofcrusted sca-bies.PLoSNeglTropDis.2013;7:e2387.

5.SalavastruCM, Chosidow O, Boffa MJ,Janier M, Tiplica GS. Europeanguidelineforthemanagementofscabies.JEurAcad DermatolVenereol.2017;31:1248---53.

6.Towersey L, Cunha MX, Feldman CA, Castro CG, Berger TG. Dermoscopy of Norwegian scabies in a patient with acquired immunodeficiency syndrome. An Bras Dermatol. 2010;85:221---3.

7.Chavez-AlvarezS,Villarreal-MartinezA,ArgenzianoG, Ancer-Arellano J, Ocampo-Candiani J. Noodle pattern: a new dermoscopicpatternfor crustedscabies(Norwegianscabies). JEurAcadDermatolVenereol.2018;32:e46---7.

8.LacarrubbaF,MicaliG.VideodermatoscopyandScabies.J Pedi-atr.2013;163:1227.

9.CinottiE,LabeilleB,CambazardF,BironAC,CholC,Leclerq A,et al.Videodermoscopycomparedtoreflectanceconfocal microscopyforthediagnosis ofscabies.JEurAcadDermatol Venereol.2016;30:1573---7.

10.ScanniG.Themite-galleryunit:anewconceptfordescribing scabiesthroughentodermoscopy.TropMedInfectDis.2019:4, pii:E48.