Only after Dwight was diagnosed last August did his parents' symptoms-the unexplained rashes, diarrhea, swollen lymph nodes-made sense to doctors.

The purpose is to detect hepatitis C or AIDS tuberculosis, AIDS or skin rash, gastrointestinal symptoms, stomatitis, liver damage, bone marrow transplantation and blood lipid abnormalities, and so on.

Its symptoms may include fever, fatigue4, weight loss, skin rashes, a fungal5 infection of the mouth known as thrush, lack of resistance to infection, and swollen lymph nodes.