Conditions which are more common in people living with HIV than in the general population and which can indicate underlying HIV infection are known as HIV indicator conditions.
Some HIV indicator conditions are caused or exacerbated by HIV as it destroys the immune system. Of these, a number are ‘AIDS defining’, that is they occur when the immune system is seriously impaired and HIV infection has progressed to AIDS (for example Kaposi’s sarcoma). Others have the same route of transmission as HIV (for example sexually transmitted infections).