An Bras Dermatol. 2011;86(1):79-4.

Dermoscopic patterns of molluscum contagiosum: a studyof 211 lesions confirmed by histopathology *

Padres dermatoscpicos do molusco contagioso: estudo de 211 leses

confirmadas por exame histopatolgico

Mayra Ianhez 1 Silmara da Costa P. Cestari 2

Mauro Yoshiaki Enokihara 3 Maria Bandeira de Paiva Melo Seize 4

Abstract: BACKGROUNDS: Although easily diagnosed, molluscum contagiosum may present as a singlelesion or as several small, inflamed lesions of difficult diagnosis. OBJECTIVE: To describe the dermoscopic characteristics of molluscum contagiosum and to compare thefindings from clinical examination and dermoscopy. METHODS: Histopathologically confirmed lesions were evaluated clinically and dermoscopically in 57patients. RESULTS: At clinical examination and dermoscopy of 211 lesions, orifices were visualized in 50.24% and96.68% of the lesions, and vessels in 6.16% and 89.10%, respectively. The vascular patterns found inthe 188 lesions in which vessels were found at dermoscopy were the crown (72.34%), radial (54.25%)and punctiform patterns (20.21%). Half of the 188 lesions had a combination of vascular patterns, withthe flower pattern (a new vascular pattern) being found in 19.68% of cases. More orifices and vesselswere identified at dermoscopy than at clinical examination, including cases with inflammation or peri-lesional eczema and small lesions. Punctiform vessels were associated with inflammation, excoriationand perilesional eczema. CONCLUSIONS: Dermoscopy performed on molluscum contagiosum lesions proved superior to dermatologi-cal examination even in cases in which clinical diagnosis was difficult. The presence of orifices, vessels andspecific vascular patterns aids diagnosis, including differential diagnosis with other types of skin lesion.Keywords: Dermatology; Diagnostic equipment; Microscopy; Molluscum contagiosum

Resumo: FUNDAMENTOS: Embora de fcil diagnstico, o molusco contagioso pode apresentar-se comoleses inflamadas, nicas ou pequenas de difcil diagnstico. OBJETIVO: Descrever caractersticas dermatoscpicas do molusco contagioso e comparar achados doexame clnico e dermatoscpico. MTODOS: Avaliou-se clnica e dermatoscopicamente leses confirmadas pela histopatologia em 57pacientes. RESULTADOS: Nos exames clnico e dermatoscpico de 211 leses, foram visualizados orifcios em 50,24%e 96,68% das leses e vasos em 6,16% e 89,10% delas, respectivamente. Os padres vasculares encontra-dos em 188 leses que apresentaram vasos dermatoscopia foram coroa (72,34%), radial (54,25%) epuntiforme (20,21%). Metade das 188 leses apresentou padro vascular combinado, sendo o padro emflor (novo padro vascular) responsvel por 19,68%. Foram identificados mais orifcios e vasos no examedermatoscpico que no clnico, inclusive naquelas com inflamao, eczema perilesional e de tamanhopequeno. Vasos puntiformes relacionaram-se com inflamao, escoriao e eczema perilesional. CONCLUSES: A dermatoscopia das leses de molusco mostrou-se superior ao exame dermatolgicomesmo quando seu diagnstico clnico torna-se difcil. A presena de orifcios, vasos e padres vascula-res especficos auxilia no seu diagnstico e na diferenciao de outras leses de pele.Palavras-chave: Dermatologia; Equipamentos para diagnstico; Molusco contagioso

Received on 20.11.2009.Approved by the Advisory Board and accepted for publication on 11.12.2010. * Trabalho realizado na Universidade Federal de So Paulo / Escola Paulista de Medicina (UNIFESP/EPM) So Paulo (SP), Brasil.

Conflito de interesse: Nenhum / Conflict of interest: NoneSuporte financeiro: Nenhum / Financial funding: None

1 Mdica colaboradora do Ambulatrio de Dermatologia da Universidade Federal de Gois - Goinia (GO), Brasil.2 Doutora em Dermatologia - Professora Adjunta do Departamento de Dermatologia da Universidade Federal de So Paulo / Escola Paulista de Medicina

(UNIFESP/EPM) - So Paulo (SP), Brasil. 3 Doutor em Dermatologia - Mdico colaborador do Ambulatrio de Dermatologia da Universidade Federal de So Paulo (UNIFESP/EPM) - So Paulo (SP), Brasil.4 Mestre em Dermatologia.

2011 by Anais Brasileiros de Dermatologia

INVESTIGAO74

An Bras Dermatol. 2011;86(1):79-4.

Dermoscopic patterns of molluscum contagiosum: a study of 211 lesions confirmed by histopathology 75

INTRODUCTIONMolluscum contagiosum is a viral infection of

the epidermal keratinocytes that results in a skinlesion with characteristic intracytoplasmic inclusions.Lesions are generally numerous, characteristically 2-4mm umbilicated skin-colored papules, with a translu-cent, glossy appearance, located at various sites onthe skin surface. 1

Other factors may hamper diagnosis of mollus-cum contagiosum, such as: lack of central umbilica-tion, 2 associations with other types of dermatologicallesions, 3 atypical lesions, 4 small, single, initiallesions, 5 inflammatory lesions and lesions with perile-sional eczema. 6 This difficulty in diagnosing the con-dition may be present at the initial evaluation, duringtreatment or in the follow-up of the patient.

Various diagnostic methods may facilitate theclinical diagnosis of lesions resulting from this infec-tion, including dermoscopy. This is a noninvasivetechnique whose principal application was initiallydirected towards the early diagnosis of skinmelanoma and differentiation with melanocyticlesions; however, it has also been used to describe thecharacteristics of other dermatoses visible using thistechnique, including molluscum contagiosum. 7

The dermoscopy pattern described in cases ofmolluscum contagiosum reported in four publica-tions included the presence of a central yellowish-white structure and vessels around the lesion (vesselsin a crown pattern). 5, 7-9

The objective of the present study was to iden-tify the dermoscopic patterns of molluscum contagio-sum and to compare them with the patterns that havealready been described.

MATERIAL AND METHODSA total of 211 lesions found in 57 patients

receiving care at a dermatology outpatient clinic formolluscum contagiosum, diagnosed by clinical exam-ination and dermoscopy and confirmed byhistopathology between July 2006 and December2007 were included in the study. Exclusion criteriaconsisted of curetted lesions with any otherhistopathological diagnosis.

The study was approved by the institutionsInternal Review Board. All the patients or their par-ents or guardians signed an informed consent formagreeing to participate in the study, permitting photo-graphic documentation to be obtained, dermoscopyto be performed on the lesions and the curetted mate-rial to be sent for histopathology, as well as givingtheir consent to undergo the proposed treatment.

Preferentially, at least one small lesion, twolesions with inflammation or perilesional eczema andtwo of characteristic size and appearance were select-

ed in each patient with five or more lesions. The pres-ence of inflammation or perilesional eczema wasincluded to permit observation of whether the clinicalalterations affect the dermoscopic appearance of mol-luscum contagiosum or its size.

During clinical examination, data such as thegender and age of the patient, the size of the lesions,the presence or absence of an orifice, vessels, inflam-mation and/or excoriation and perilesional eczemawere recorded. At dermoscopy, the following charac-teristics were registered: the size of the lesions (inmm), the presence or absence of an orifice and vesselsand, if vessels were present, the vascular pattern.

The size of the lesions was determined by a der-moscope and classified according to the followingscale: a) small: 1.5 mm; b) medium-sized: > 1.5 mmand 3 mm; or c) large: > 3 mm.

The vascular patterns were classified in accor-dance with the study conducted by Vsquez-Lpez etal. 9 in which the vascular patterns of nontumoral der-matoses visualized at dermoscopy are described.

At least two experienced dermatologists famil-iar with dermoscopy in molluscum contagiosummade the clinical and dermoscopic diagnoses and per-formed curettage.

All the lesions selected for the study were pho-tographed twice, clinically and dermoscopically, andthe data were recorded and stored. All poor qualitydigital images were excluded from the study. SonyCybershot P93 and Canon SD800 digital cameras wereused, as well as a Heine Delta 20 dermatoscopeattached directly to the aforementioned cameras.Alcohol gel was used at the interface between the skinand the dermatoscope.

Following clinical examination and der-moscopy, curettage of the lesions was performed in allthe patients, who were then given written and verbalinstructions to be followed in the post-operative peri-od. A return follow-up visit was scheduled duringwhich the histopathology results of the treated lesionswere given to the patients. The lesions were analyzedby pathologists from the Pathology Department of theinstitution.

To avoid bias caused by vasoconstrictioninduced by the topical anesthesia used at curettage,dermoscopy was performed before the product wasadministered.

The chi-square test was used to associate clini-cal changes with vascular patterns. Probability (p)