Selenium Sulfide-induced Scalp Discoloration: A Neglected Disease

A 13-month-old boy with a history of tinea capitis presented with a brown-red discoloration on the scalp that had been present for 1 month [Figure 1a]. He had used selenium shampoo twice 2 months ago. He was diagnosed with tinea capitis 1 year ago and was cured with a 5-week course of oral fluconazole. Recurrent tinea capitis was suspected, and direct microscopy was performed. No hyphae but multiple Malassezia spores could be found using calcofluor white staining [Figure 2]. Trichoscopy showed multiple brown-red polygonal structures [Figure 1b], while no specific structures were observed after lesion removal [Figure 1b]. Terra firma-forme dermatosis was initially suspected. During mycology examination, we found that lesions were easily removed with a swab without alcohol [Figure 3]. Therefore, selenium sulfide-induced scalp discoloration was diagnosed. Lesions disappear completely after gentle skin cleansing [Figure 1c].Figure 1: (a) Scalp brown-red discoloration, (b) Trichoscopy showed multiple brown-red polygonal structure, white area showed no structure after lesion removal, (c) Lesions disappear completely after cleansingFigure 2: Multiple Malassezia spores under calcofluor white stainingFigure 3: Lesions were easily removed with swab without alcoholSelenium sulfide-induced scalp discoloration is caused by the topical use of selenium sulfide-containing shampoos in patients, resulting in discoloration of the skin and appendages.[1] Selenium sulfide is applied to the scalp for several minutes twice a week. After 2–8 weeks, a brown-red discoloration is deposited on the scalp.[1] This condition can be easily misdiagnosed as recurrent tinea capitis or terra firma-forme dermatosis.[2] This case illustrates that an attempt to remove the selenium sulfide-induced scalp discoloration with a swab without alcohol can serve as a quick and inexpensive diagnostic tool, which is important to avoid unnecessary evaluations such as biopsy. Declaration of consent The authors certify that they have obtained all appropriate consent forms, duly signed by the parent(s)/guardian(s) of the patient. In the form, the parent(s)/guardian(s) has/have given his/her/their consent for the images and other clinical information of their child to be reported in the journal. The parents understand that the names and initials of their child/children will not be published and due efforts will be made to conceal their identity, but anonymity cannot be guaranteed. Financial support and sponsorship This work was supported by the Hangzhou Science and Technology Bureau, China (20220919Y013) and the Hangzhou Science and Technology Bureau, China (202004A17). Conflicts of interest There are no conflicts of interest.