A 30-year-old man undergoes a lung biopsy, which shows multiple nodular lesions consisting of large epithelioid cells surrounded by lymphocytes and fibroblasts. There is an area of necrosis in the center of some nodules. Numerous acid-fast bacilli are demonstrated by Ziehl-Neelsen staining within the cytoplasm of epithelioid cells. Silver stains for fungi are negative. Which of the following is the MOST likely condition that predisposed the patient to this pulmonary disease?