Trimethoprim-sulfamethoxazole treatment of Pneumocystis carinii pneumonitis

Abstract

PNEUMOCYSTIS CARINII pneumonitis occurs almost exclusively in the debilitated or immunosuppressed individual? Mortality without therapy in this disease exceeds 50%. Treatment with pentamidine isethionate has improved the survival rate to 60 to 95%. However, pentamidine is toxic; adverse reactions occur in approximately 50% of recipients. Trimethoprim-sul famethoxazole is apparently effective and less toxic/ In this report we summarize our experience with TMP-SMZ treatment of five children with P. carinii pneumonitis, CASE REPORTS The age, sex, underlying disease, and diagnostic procedures for five patients with P. carinii infection are listed in Table I. Symptoms in four children were present for four to 21 days before starting treatment. One patient (No. 2) had easy fatiguabilitY, dyspnea, and mild cough for nine weeks; his respiratory symptoms had progressed during the last week. Such an insidious course has been recognized in P. carinii infections/All children had tachypnea, cough, and fever; three were cyanotic. At the time of diagnosis blood Pao2 was over 50 mm Hg in the three survivors and under 50 mm Hg in the two children who died subsequently. Total and differential white blood counts were not helpful in diagnosis but reflected either the underlying disease (Patient 1) or the effects of chemotherapy (Patients 2 to 5). All patients had extensive, bilateral interstitial infiltrates as demonstrated by chest radiographs?. 3 The first patient also developed a spontaneous pneumothorax. Aerobic and anaerobic bacteria, mycobacteria, fungi, and viruses were sought in all cases in smears and cultures of lung biopsy specimens; none was isolated. All lung biopsy