Pneumocystis carinii pneumonitis in children with malignancies

Pneumocystis carinii pneumonitis occurred in 51 (4.1 per cent) of 1,251 children with malignancies. The annual incidence was proportional to the number of patients at risk and was unrelated to season, age, sex, place of residence, or the environmental factors investigated. The disease was characterized by fever, marked tachypnea, flaring of nasal alae, intercostal retraction, frequently cyanosis, and roentgenographic evidence of bilateral diffuse alveolar disease. The diagnosis was established by the identification of P. carinii in material obtained from percutaneous transthoracic needle aspiration of the lung. Three stages of the pathologic pattern were delineated in correlation with clinical manifestations. Forty-one patients were treated with pentamidine isethionate; 28 (68 per cent) of them recovered from the pulmonary infection. A second episode occurred in four. Adverse effects of the drug are usually reversible.