Case of the Month - June 2022

A 4-year-old boy with a history of infantile eczema and developmental delay was brought to his pediatrician because of a dry, itchy scalp lesion. Topical hydrocortisone had been prescribed with no relief. He otherwise appeared well. Examination of the scalp showed diffuse dry plaques.

The skin was scraped and sent for fungal culture. After 10 days, a pigmented, yeast-like colony was observed in the mycobiotic culture bottle (Figure 1). The organism was then subcultured on Sabouraud dextrose agar and after 4 weeks, mold-like growth was observed (Figure 2). Black aerial hyphae were observed, and the colony reverse was also darkly pigmented. A lactophenol cotton blue tape preparation was prepared and examined under the microscope (Figure 3).

What is the genus of this mold?

 June 2022 a 
Figure 1 - Growth in a fungal culture bottle.

June 2022b 
Figure 2. Growth on Sabouraud dextrose agar. Slow-growing black colonies with a velvety surface.

June 2022c 
Figure 3. Stock image photomicrograph of a lactophenol cotton blue smear showing hyphae with conidiophores (1000X)