Differential Diagnosis
- Single most likely diagnosis
- HIV infection, III clinical stage: This diagnosis is the most likely due to the patient's symptoms, including weakness, weight loss, fever, oral candidiasis, and polylymphadenopathy, which are consistent with the clinical manifestations of HIV infection at an advanced stage. The patient's history of opportunistic infections (pneumonia, herpes zoster) and high-risk sexual behavior further supports this diagnosis.
- Other Likely diagnoses
- HIV infection, IV clinical stage: Although less likely than stage III, stage IV (which often refers to AIDS, the most advanced stage of HIV infection) could be considered if the patient's symptoms and opportunistic infections are severe enough to meet the criteria for AIDS.
- HIV infection, II clinical stage: This stage is characterized by persistent generalized lymphadenopathy, which the patient has, but the presence of opportunistic infections and more severe symptoms like weight loss and fever might suggest a more advanced stage.
- Do Not Miss (ddxs that may not be likely, but would be deadly if missed.)
- Tuberculosis (TB): Given the patient's symptoms of fever, weight loss, and history of pneumonia, TB should be considered, especially if the patient has been exposed to TB or has risk factors for TB.
- Lymphoma: Both HIV-related lymphoma and other types of lymphoma could present with similar symptoms, including lymphadenopathy, fever, and weight loss.
- Other opportunistic infections: Depending on the patient's specific immune status and exposure history, other opportunistic infections (e.g., toxoplasmosis, cryptococcosis) could be considered.
- Rare diagnoses
- Castleman disease: A rare disorder that involves an overgrowth of cells in the body's lymph nodes, which could explain the lymphadenopathy but would be less likely given the full clinical picture.
- Other immunodeficiency disorders: While less likely, other primary immunodeficiencies could present with similar symptoms, including recurrent infections and lymphadenopathy, but the patient's sexual history and specific opportunistic infections point more strongly towards HIV.