Onychoscopic Analysis of Cyclophosphamide-Induced Polydactylic Bluish-Gray Discoloration in a Case of Pemphigus Foliaceus.

Cyclophosphamide, an alkylating agent, has rarely been observed to cause a bluish discoloration of nails, an occurrence that is typically underreported. We describe the case of a middle-aged male undergoing dexamethasone-cyclophosphamide pulse therapy for pemphigus foliaceus, who exhibited bluish-gray discoloration of the nails. It is crucial to differentiate this presentation from other conditions such as nail apparatus melanoma (NAM), which may manifest in a slightly different manner. We also report the onychoscopic findings observed in this case.