A Middle-Aged Man Presenting with a New Asymmetrical Poikilodermatous Erythema on the Lateral Neck
January 2022
in “
Clinical Cases in Dermatology
”
TLDR A man developed a unique rash on his neck after taking niacinamide, and doctors recommend considering niacinamide as a cause for similar rashes and using dermatoscopy for diagnosis.
The document presents a case of a middle-aged man who developed a new unilateral poikilodermatous rash on the lateral aspect of his neck after being treated for comedones and seborrhea with a low glucose-index diet, niacinamide, and riboflavin for 6 months. Dermatoscopy of the affected area showed a uniform pattern of reticular linear vessels pierced by the whitish hair follicle openings. After considering the patient's history, clinical presentation, and dermatoscopic clues, the diagnosis of niacinamide-induced poikilodermatous flushing was made. This is the first report of dermatoscopy of niacinamide-induced poikilodermatous erythema. The document suggests that physicians should consider the role of niacinamide supplementation in patients with facial flushing/head-and-neck erythema, especially if it's transient and asymmetrical, as even non-toxic doses may evoke the symptoms. Dermatoscopy is recommended as a useful auxiliary diagnostic tool.