Acquired immunodeficiency syndrome has a complex and diverse clinical presentation that can involve all systems and manifest as opportunistic infections or associated tumors. When patients present with typical symptoms of AIDS, CD4+ cell counts usually drop below 200/ul, and untreated individuals have an average survival of 12 to 18 months after entering this phase.
Common opportunistic infections include viral infections such as cytomegalovirus retinitis, herpes zoster (caused by varicella zoster virus), and oral hairy leukoplakia (caused by EBV); bacterial infections such as tuberculosis, Mycobacterium avium infection; fungal infections such as pneumocystis pneumonia (PCP), cryptococcal meningitis, Candida albicans causing esophagitis and oral infections; parasitic infections such as Toxoplasma gondii encephalopathy, diarrhea caused by Cryptosporidium, etc.
Common malignant tumors that are representative of HIV include non-Hodgkin’s lymphoma and Kaposi’s sarcoma, which are also associated with viral infections, such as lymphoma usually associated with EBV infection and Kaposi’s sarcoma associated with human herpesvirus 8 infection.