Review Question - QID 108608

A 7-year-old boy is brought in to your clinic by his mother, who is complaining of her son’s “dry scalp and hair loss.” She reports a scaling spot on his scalp developed around 2 months ago, soon after moving to a new school, which then became a larger bald spot. She denies that anyone in the household is exhibiting similar symptoms, but does recall a note that came home from school warning of a lice outbreak. Thus far, she has only tried daily baths with little improvement. The patient denies pain or itchiness, but the mother reports she does notice him scratching his scalp. The mother also reports that since her son has started at the new school, she has noticed an increase in his tics including excessive blinking and clearing of his throat. The patient's medical history is significant for asthma, allergic rhinitis, and attention deficient hyperactivity disorder. His current medications include fluticasone, salmeterol, loratadine, and methylphenidate. Family history includes obsessive compulsive disorder in his older sister. The mother also reports her father had a debilitating skin and joint disorder. On examination, you note swollen lymph glands at the back of the patient's ears and neck, and there are residual black dots within a patch of alopecia. Which of the following is the most likely diagnosis?