RESUMO
BACKGROUND: Longitudinal melanonychia (LM) is a worrisome sign in both children and adults. Nail apparatus melanoma (NAM) can be related to LM, but it is very rare in children. Dermoscopic signs of benign lesions in children can be similar to melanoma; therefore, it is important to review dermoscopy of LM in children to make the best decision in performing biopsy. AIMS: Biopsy taking is very challenging in LM in children. Most lesions are benign in children. The aim of this study was to review dermoscopic signs of LM in children and compare them with adults. MATERIALS AND METHODS: In this prospective study a total of 108 LM (35 children and 73 adults) were undergone dermoscopy of LM. Dermoscopic features were compared in children and adults; both for benign lesions proven by biopsy or follow up and melanomas diagnosed histopathologically. RESULTS: Black background, black band color, band color diversity and pseudo-Hutchinson's sign were more frequent in children in comparison with benign adult melanonychia. Some children's dermoscopic features of LM such as broad band width, Band color diversity, Hutchinson's sign, gray band color, asymmetry of pattern, and regression were similar to melanoma, but we did not find any melanoma by biopsy and/or follow up among children. We also detected the newly described "zigzag" pattern in four children. CONCLUSION: Dermatologists should consider all dermoscopic features of a lesion, dermoscopic sign changes in follow-up, medical, and familial history of the patient in deciding to perform biopsy of LM in children.
RESUMO
BACKGROUND: Pemphigus is an autoimmune intraepidermal bullous disease which can affect skin and∕or mucous membranes. Trichoscopy is a non-invasive tool that can help in the clinical diagnosis especially if the patient is presented with only scalp lesions. We conducted this study to investigate the trichoscopic features of pemphigus scalp lesions. METHODS: A total of 100 patients with confirmed diagnosis of pemphigus entered the study; Seventy-nine patients were diagnosed as pemphigus vulgaris (PV) and 21 as pemphigus foliaceus (PF). Trichoscopy of the scalp lesions was performed, and three dermatologists examined separately the trichoscopic images of each patient. The results were re-checked simultaneously by the examiners. Association between variables was analyzed by using different tests including: chi-square test or Fischer's exact test, independent T-Test or Mann-Whitney nonparametric test and logistic regression model when applicable. RESULTS: Mean age of the patients was 45.41 ± 11.13 years, and 58% of cases were male. The most common trichoscopic features observed among all cases were diffuse scaling (71/100), presence of any types of vessels (67/100), and extravasation (63/100). Positive anagen pull test, extravasation, yellow hemorrhagic crust, and polymorphic vessels were more commonly seen in PV than PF cases (P value < 0.05), and by having data of these variables, we can differentiate between PV and PF scalp lesions with 74% sensitivity and 91% specificity. CONCLUSION: Trichoscopy can help in clinical diagnosis of pemphigus scalp lesions but should be followed by other modalities such as biopsy and direct immunofluorescence for definite diagnosis.