Misdiagnosed crusted scabies in an AIDS patient leads to hyperinfestation.

Crusted scabies is a severe, highly contagious form of classic scabies caused by the mite Sarcoptes scabiei var hominis. Crusted scabies is more common in immunosuppressed populations and overcrowded environments. In this condition, the host's immune system is overwhelmed and unable to defend against the mites on the skin, resulting in hyperinfestation of the host. Diagnosis can be challenging because the condition resembles other common skin conditions, such as plaque psoriasis. Furthermore, delayed diagnosis and inappropriate treatment can lead to worsening of the condition. We report a case of crusted scabies that was initially misdiagnosed in a 34-year-old incarcerated man with multidrug-resistant human immunodeficiency virus/AIDS. The patient had a complicated but complete recovery after treatment with permethrin and ivermectin was instituted.