A case of doxycyclin-induced photo-onycholysis with dermoscopic features

Abstract

A 16-year-old boy was referred to us with asymptomatic nail discoloration affecting his fingernails. The patient was receiving treatment with 200 mg/day oral doxycycline administration for six weeks due to brucellosis. His remaining medical history was unremarkable except for intense sun exposure. The dermatological examination revealed a distal black and brown discoloration with half-moon shaped edges affecting all the fingernails (Figure 1). On dermoscopic examination, bluish black discoloration, brown dots, and proximal brown discoloration with sharp linear edges were observed (Figure 1). No yellow oil spots, blood spots, pitting, or subungual hyperkeratosis were detected. No cutaneous lesions were observed elsewhere. Direct microscopic examination with potassium hydroxide preparation did not show the presence of fungal element. Bacteriological investigations revealed no infectious agents. A diagnosis of doxycycline-induced photo-onycholysis was made.