HIV-associated Pneumocystis carinii pneumonia with and without primary prophylaxis with pentamidine inhalation: Are there differences?

Objective: To study the effect of pentamidine aerosol inhalation, known to be effective and well tolerated in the primary prevention of HIV-associated Pneumocystis carinii pneumonia (PCP), on the severity, on clinical and radiological findings and prognosis of break-through PCP. Patients and method: Data were obtained from the case notes of 17 men (mean age 36 [23-55] years) with HIV-associated PCP, treated between 1989 and 1994, who had received primary prophylaxis with pentamidine aerosol. During the same period 42 patients with HIV-associated PCP but no pentamidine prophylaxis (39 men, three women; mean age 36 [21-67] years) were also treated. Bronchoalveolar ravage of the most affected segment was performed. Diagnostic measures and treatment remained constant during the period of observation. Results: The clinical presentation was the same in the two groups. There was also no difference between them regarding sensitivity to the lavage (94 and 98%). However, infiltration of the upper segments was significantly more common in the prophylaxis group (90 and 43%; P < 0.02). There was no statistically significant difference between the two groups in death rate (13 and 7%) and the long-term prognosis after PCP (survival time 18 and 24 months, respectively). Conclusion: Primary prophylaxis of PCP had no significant effect other than altering the distribution pattern of the pneumonic infiltrates towards the apical segments.