A 30-year-old female with HIV infection presents with a non-productive cough, fever, and shortness of breath. On physical examination, breath sounds are decreased bilaterally. Oxygen saturation is 90% on room air. What is your next step?
This patient's HIV status and symptoms are suggestive of Pneumocystis jirovecii pneumonia (PJP). To confirm this, a chest X-ray or chest CT should be ordered, which may show diffuse interstitial infiltrates. The definitive diagnosis is usually made by identifying Pneumocystis jirovecii in respiratory specimens, typically via bronchoalveolar lavage. Given the severity of the patient's symptoms and low oxygen saturation, she should be hospitalized, and empiric treatment with trimethoprim-sulfamethoxazole should be initiated promptly.