Scabies

A 16-year-old boy sought medical attention because of extremely pruritic nodules on the penis and scrotum. He also had mild itching on the wrists and between several finger webs.

Key point: This distribution of a pruritic dermatosis is classic for scabies. This disorder is acquired primarily via close, personal contact. The patient admitted to sexual relationships with several older women. A mineral oil prep of a scraping from the crusted center of a scrotal nodule revealed the characteristic mite.

Treatment: The eruption cleared following 2 oral doses of ivermectin, 200 µg/kg.  

Note: While topical permethrin therapy may be effective, the CDC now also recommends ivermectin as first-line therapy.