Study Objective: To evaluate inhaled or reduced-dose intravenous pentamidine for the treatment of patients with mild Pneumocystis carinii pneumonia.
Design: Open, nonrandomized pilot study; measurement of pentamidine concentrations in plasma and bronchoalveolar lavage fluid.
Patients: Of 22 men with mild P. carinii pneumonia (Po2 ≥ 55 mm Hg), 15 (9 in the inhaled group and 6 in the intravenous group) received treatment for their first episode and 7 for a repeat episode.
Interventions: Pentamidine isethionate, 4 mg/kg body weight by inhalation, or 3 mg/kg intravenously, was given once daily, as long as clinically indicated.
Measurements and Main Results: Of the 13 patients in the inhaled group, 9 had a satisfactory response; and of the 10 in the reduced-dose intravenous group, 9 had a satisfactory response. Major adverse reactions occurred in two patients in each group. Three patients in the inhaled group appeared to have had early relapses. Bronchoalveolar lavage fluid concentrations of pentamidine ranged between 16.8 ± 7.3 ng/mL and 149.7 ± 38.2 ng/mL in the inhaled group and 3.4 ± 0.2 ng/mL and 10.9 ng/mL in the intravenous group.
Conclusions: Inhaled or reduced-dose intravenous pentamidine may be an effective and less toxic therapy for mild P. carinii pneumonia. These regimens are not recommended for general use until larger controlled trials are conducted.