A 40-year-old woman who had been receiving prednisone and azathioprine for the treatment of systemic lupus erythematosus complained of a widespread, intensely pruritic, heavily scaling rash.
Key point: The combination of itching massive scaling suggests the diagnosis of crusted scabies. This variety of scabies is seen in those who are immunosuppressed or immunocompromised (typically HIV+). A mineral oil scraping of the scale should easily demonstrate mites, as it did in this case.
Treatment: Repeated oral doses of ivermectin along with topical permethrin application were required to clear her infestation.
Note: This is highly contagious. All household members should be treated on prophylactic basis.