A 23-year-old female came to a dermatology clinic with the complaints of brittle scalp hair and the presence of firmly adherent, black, gritty, hard nodules along the hair shaft. Pruritus is absent. What is the most probable causative agent?

The presence of brittle scalp hair and firmly adherent, black, gritty, hard nodules along the hair shaft is suggestive of black piedra. The causative agent of this condition is Piedraia hoae. Piedra is a superficial fungal infection of the hair shaft. It is of two types Black piedra: It is characterized by the presence of firmly adherent, black, gritty, hard nodules along the hair shaft. Scalp hair is most often affected. It is caused by Piedraia hoae. White piedra: It is characterized by the presence of soft, white or light brown transparent nodules that are easily detached from the hair. It affects pubic, axillary, facial hair more commonly than scalp hair. It is caused by Trichosporon beigelii. Management: Shaving or cutting of the affected hair along with topical antifungals Reference: Ananthanarayan and Paniker&;s Textbook of Microbiology Tenth edition