Abstract
Dermoscopy allows non-invasive observation of the surface and sub-surface features of pathological skin conditions and reveals characteristic novel patterns that are diagnostic. The aim of the present study was to assess the dermoscopic features in Pityriasis rosea (P. rosea / PR) and relate the dermoscopic diagnosis with the clinico-histopathological diagnosis. This is a prospective, observational study conducted over a period of 18 months in 15 patients who presented with Pityriasis rosea skin lesions to our outpatient clinic and satisfied the relevant inclusion and exclusion criteria. The lesions were analyzed clinically and subjected to dermoscopy and histopathology and the resulting diagnoses were compared. On dermoscopy, white collarette scaling was seen in 100% of the cases. Vascular findings like red dots in a patchy distribution were noted in 13 (86.66%) cases. The background color was yellow (66.66%), dull red (20%) or light red (13.33%). Of the 15 cases which were diagnosed clinico-dermoscopically as PR, biopsy was done in 13 cases, of which 11 cases showed features favorable of PR and 2 cases could not be differentiated from dermatitis. Overall, there was a positive correlation between the clinical, dermoscopic and histopathological diagnoses in 11 of the 15 patients (73.33%).Based on the observations noted in the present study, it may be concluded that dermoscopy is a useful, non-invasive tool in making a definitive diagnosis of pityriasis rosea.