I don't normally do this, but I guess one time is OK ;-) The patient is immunocompromised, but it's not Kaposi's sarcoma.
Correct answer: Norwegian scabies, also known as crusted scabies. It is a more serious variant of the relatively common scabies skin infection. It occurs only in immunocompromised patients and is very hard to treat with topical medication, as the mites are protected under the layers of crusted skin.