Immunoblastic lymphadenopathy presents with fever, malaise, cough, dyspnea, lymphadenopathy, hepatosplenomegaly, hypergammaglobulinemia, interstitial pulmonary infiltrates, mediastinal adenopathy, and effusions. The diagnosis is made on the basis of lymph node biopsy. Based on the course in our patients and the cases presented in previous reports, a suggested program of treatment for immunoblastic lymphadenopathy includes administration of moderate doses of steroids initially, with a subsequent increase to a higher dosage if desired improvement does not occur. Chemotherapy with three drugs, cyclophosphamide, vincristine, and prednisone, is indicated if remission using steroids fails. The diagnostic dilemma of whether pulmonary infiltrates are due to the disease itself or to pulmonary infection or to cytotoxic changes from chemotherapy always exists and often requires specimens from either transbronchoscopic or open-lung biopsy for definitive diagnosis and treatment.