Bilateral pneumothoraces hasten mortality in AIDS patients receiving secondary prophylaxis with aerosolized pentamidine. Association with a lower Dco prior to receiving aerosolized pentamidine.

We have administered aerosolized pentamidine (AP) to 48 AIDS patients for secondary prophylaxis of Pneumocystis carinii pneumonia (PCP). Pentamidine 60 mg was administered by ultrasonic nebulization (Fisoneb) five times during the first two weeks and then every two weeks. The mean follow-up was 343 +/- 22 days. PCP recurred in ten patients, 297 +/- 33 days after starting AP therapy. All responded to anti-Pneumocystis therapy but two patients died of unrelated reasons (20 percent mortality). Five patients developed bilateral pneumothoraces 260 +/- 35 days after starting AP therapy. Recurrence of PCP could be documented in only one patient. All died 66 +/- 27 days after the onset of the first pneumothorax. Only 5 of 33 patients without recurrence of pneumonia or pneumothorax died during the study period (15 percent mortality). No association was found between the development of pneumothorax and age, smoking, previous respiratory or infectious problems, time from last PCP and the initiation of AP therapy, and treatment duration of last PCP. Patients with pneumothoraces had a significantly lower Dco (58.6 +/- 2.6 percent predicted) prior to AP therapy than patients with recurrence of PCP without pneumothoraces (81.1 +/- 2.1 percent predicted) or patients with no recurrence of PCP (67 +/- 2.5 percent predicted) (p less than 0.05, ANOVA). In conclusion, bilateral pneumothoraces are associated with a hastened mortality in patients receiving AP for secondary prophylaxis of PCP. Low Dco before AP therapy is associated with an increased risk of bilateral pneumothoraces in patients treated with AP for secondary prophylaxis of PCP.