INTRODUCTION: The differential diagnosis of pulmonary nodules in a patient with acquired immune deficiency syndrome(AIDS) is broad. We present a case where an organized approach with appropriate pathologic investigations led to the correct diagnosis.
CASE PRESENTATION: A 38-year-old male with a history of Acquired Immune Deficiency Syndrome(AIDS) presented with one month of fever and blood-tinged sputum. His CD4+ T lymphocyte count was 10/μl and he was taking no medicines. The patient was diagnosed with AIDS one year prior when he presented with Pneumocystis pneumonia(PCP). At that time he had a positive tuberculin purified protein derivative test. Sputum smears were negative for acid fast bacilli(AFB) and he refused treatment for latent tuberculosis(TB) infection. The patient reported dyspnea on exertion, a five pound weight loss and night sweats. He denied exposure to TB. He denied chest pain and orthopnea. The patient was a native of Colombia where he had received the Bacille of Calmette-Guerin(BCG) vaccine. He immigrated to New York City in 1990, but visited Columbia and Brazil within the year prior to admission. He reported sex with multiple male partners. He denied alcohol, tobacco or drug use. On admission, the patient was in mild respiratory distress. Oxygen saturation on room air was 91%. Lung examination was notable for mild crackles diffusely. Cardiac, abdominal and neurological examinations were normal. There was no rash. The white blood cell count(WBC) was 2800/μl, hematocrit was 35.3%, serum creatinine was 0.8 mg/dl and lactate dehydrogenase was 241 U/L. Sputum was 2+ on acid fast stain. The chest radiograph showed multiple bilateral nodules. The patient was placed in isolation and supplemental oxygen was begun. He was started on isoniazid, rifampin, pyrazinamide and ethambutol for possible active TB. He was also started on trimethoprim-sulfamethoxazole for possible PCP. Subsequent sputum samples were negative for AFB. Bacterial and fungal cultures showed no growth. Rapid polymerase chain reaction probe on the AFB- positive smear was negative for TB. Urine histoplasma antigen, rheumatoid factor, anti-myeloperoxidase and anti-proteinase III antibodies were negative. A computerized tomographic scan of the chest showed multiple bilateral nodules. Bronchoscopy revealed normal appearance of the respiratory tree. Bronchial washings showed inflammatory cells and macrophages. Transbronchial biopsy showed mild interstitial inflammation. No granulomas, intra-alveolar exudates or viral inclusion bodies were seen. Stains for AFB, fungi and PCP were negative. The patient remained febrile. Respiratory distress worsened and the patient became hypotensive. He was transferred to the medical intensive care unit and placed on mechanical ventilation. He was started on norepinepherine and broad-spectrum antibacterial therapy. Clarithromycin was added for possible Mycobacterium avium-intracellulare infection. Methylprednisolone was started for possible pulmonary lymphoma. Due to diagnostic uncertainty, a video-assisted thoracoscopic lung biopsy was performed. Multiple pulmonary nodules were seen. Left lower lobe biopsy revealed sarcoma with spindle shaped cells. Staining for human herpesvirus-8(HHV-8) was strongly positive, confirming the diagnosis of Kaposi's sarcoma(KS). The patient's respiratory status worsened and he required 100% oxygen supplementation. Due to the poor prognosis the health care proxy elected to disconnect the patient from the ventilator and he expired.
DISCUSSIONS: This case report is notable for several reasons. First, KS should be considered in a patient with AIDS and pulmonary nodules even when skin lesions are absent. Second, KS can extensively involve the lung parenchyma in the absence of endobronchial lesions or pleural effusions. Third, staining for HHV-8 can be useful for the diagnosis of KS. Finally, open lung biopsy has diagnostic value in patients with AIDS when less invasive procedures are unrevealing.
CONCLUSION: KS should be considered in a patient with AIDS and bilateral pulmonary nodules. Open lung biopsy should be pursued when diagnostic uncertainty remains.
DISCLOSURE: Lewis Eisen, None.