The Unexpected Diagnosis: Refractory Pneumonia as The First Manifestation of HIV in a Low-risk Individual

Abstract

A 39-year-old previously healthy Saudi man presented with a six-week history of persistent dry cough, intermittent low-grade fever, chest heaviness, and progressive exertional dyspnea unresponsive to three outpatient antibiotic courses. Imaging revealed a new extensive pneumonic patch in the left lower and middle lobes contrasting with prior normal chest radiographs, while high-resolution CT demonstrated patchy ground-glass opacities without consolidation or cavitation. Laboratory studies showed mild anemia, leukopenia, slightly elevated inflammatory markers, and a reduced CD4 count, raising concern for underlying immunodeficiency. Routine bacterial, mycobacterial, and fungal investigations were negative, but sputum PCR confirmed Pneumocystis jirovecii, and subsequent HIV testing was positive. The patient was admitted to a monitored unit, received supplemental oxygen, and initially broad-spectrum intravenous antibiotics, followed by targeted high-dose trimethoprim-sulfamethoxazole therapy. Supportive measures included hydration, respiratory physiotherapy, nutritional optimization, and close monitoring of oxygenation, laboratory parameters, and clinical status. Antiretroviral therapy was deferred until stabilization to mitigate the risk of immune reconstitution inflammatory syndrome, with a coordinated long-term plan for secondary prophylaxis, CD4 and viral load monitoring, and follow-up imaging. This case highlights the critical need to consider HIV and opportunistic infections in adults with nonresolving pneumonia regardless of prior health status, demonstrates the importance of integrating radiographic, laboratory, and immunologic data for accurate diagnosis, and underscores the value of prompt targeted therapy combined with multidisciplinary management to optimize recovery, prevent complications, and guide long-term care.