Norwegian scabies in a patient with AIDS.

Depression of cellular and humoral immunity can result in an overwhelming infection with the mite Sarcoptes scabiei. Infections in which the densities of mites are very high are known as Norwegian, or crusted, scabies. Cases of Norwegian scabies have been reported sporadically in patients with AIDS, but the appearance of the rash on these patients can be very misleading because of the diffuse papular or psoriasiform presentation. Such patients may readily transmit scabies to others. Since the disease is curable, it should be considered in the differential diagnosis of any persistent papular or psoriasiform rash on a patient with AIDS.