Unexpected lung lesions in high resolution computed tomography (HRTC) among patients with advanced HIV disease

The present pilot study was undertaken to characterize the frequency of lung lesions in asymptomatic human deficiency virus (HIV) infected individuals with advanced HIV disease. Thirty two consecutive HIV+ homosexual males assessed for initiation of Pneumocystis carinii pneumonia (PCP) prophylaxis, were prospectively studied. All patients underwent a complete medical history, physical examination, pulmonary function tests and high resolution computed tomography (HRCT). HRCT scans were read by a single radiologist, who was blind as to the clinical status of the patient. Unexpected HRCT scan lesions were found in 60% of patients. There were no statistically significant differences between patients with normal and abnormal HRCT with respect to age, height, weight, CD4+ count, smoking history, serum albumin, alpha 1-antitrypsin level or body mass index. Forced vital capacity (FVC) (% of predicted) and peak expiratory flow rate (PEFR) (% pred) were not significantly different between groups. For patients with normal and abnormal HRCT forced expiratory volume in one second (FEV1) (% pred) was 99 +/- 12 vs 92 +/- 16, FEV1/FVC was 82 +/- 5 vs 76 +/- 9, and forced mid-expiratory flow (FEF25-75) (% pred) was 100 +/- 24 vs 77 +/- 27, respectively. There were no statistically significant differences between patients presenting with destructive versus nondestructive lung HRCT lesions. Our results demonstrate that as many as 60% of HIV-infected patients have unexpected abnormalities on HRCT at the time of starting PCP prophylaxis. We speculate that these lesions may contribute to the high frequency of spontaneous pneumothoraces previously reported in this patient population.