Case Presentation: A 29 year old male with HIV/AIDS only intermittently taking antiretroviral therapy (ART), Pneumocystis jirovecii (PJP) pneumonia actively being treated with trimethoprim-sulfamethoxazole (TMP-SMX) and prednisone, and cutaneous Kaposi sarcoma all diagnosed one month ago at an outside clinic presented to the hospital with worsening cough and shortness of breath. Initial vitals were notable for low grade fever of 99.9oF, tachycardia to 130s, and hypoxia with saturation of 88% on room air, which improved to 95% on two liters nasal cannula. Physical exam was notable for a thin, cachectic, ill-appearing male with prominent cervical lymphadenopathy and numerous violaceous plaques of varying sizes present over the face, chest, abdomen, and back and inside the oral cavity. Pulmonary exam revealed diffuse rhonchi along with absent breath sounds and dullness to percussion in the left lower lung field. CD4 count was 262/μL. Chest x-ray showed a large left hydropneumothorax. The pleural effusion was drained, and pleural studies showed an exudative effusion but were negative for bacterial, mycobacterial, fungal, and pneumocystis infection. Fluid cytology was negative for malignancy. Over the next few days, the effusion proved difficult to control as it rapidly reaccumulated. Bronchoscopy was performed, and numerous violaceous hyperpigmented lesions consistent with Kaposi sarcoma were seen in the trachea and bronchial tree. A lymph node biopsy was also positive for Kaposi sarcoma. These studies confirmed a diagnosis of pulmonary Kaposi sarcoma with pleural involvement as the underlying cause of the patient’s recurrent pleural effusions and subsequent respiratory distress.
Discussion: The differential diagnosis for shortness of breath in an HIV-positive patient who has been unable to tolerate ART is very broad, and pulmonary Kaposi is a rare diagnosis even in this susceptible population; pulmonary involvement is reported in only 5-8% of cases of AIDS-related Kaposi sarcoma. In this case, a CD4 count above 200/μL made certain opportunistic infections less likely, but an initial infectious workup was both warranted and performed given the sepsis-like nature of the patient’s presenting symptoms. Negative infectious studies led to more invasive testing, which ultimately confirmed the diagnosis of pulmonary Kaposi. The patient was started on treatment with pegylated liposomal doxorubicin with improvement in symptoms. Using a systematic approach and applying the diagnostic decision making skills that are fundamental to the practice of hospital medicine, we were able to reach an accurate diagnosis in an efficient manner.
Conclusions: Patients with HIV/AIDS are susceptible to both common ailments and rare opportunistic infections and malignancies, which makes it important to build a broad and comprehensive differential diagnosis. Using a systematic approach allows for efficient diagnosis and treatment despite the rarity of the disease.