1064 COURSE OF PULMONARY DYSFUNCTION IN CHILDREN SURVIVING PNEUMOCYSTIS CARINII PNEUMONITIS (PCP): A PROSPECTIVE STUDY

Abstract

Twenty-five pulmonary function studies were done serially in 23 children, 7-18 years of age, who had survived the acute stage of PCP and were asymptomatic. Spirometric indices, expiratory flow rates, pulmonary gas transfer factor (DLCO), blood gases and other clinical variables were assessed a few days befor hospital discharge and at 1-, 3-, 6- and 12-month intervals. Two patients developed recurrent PCP during follow-up and were studied twice. All but 5 (80%) had pulmonary dysfunction when tested initially. A decrease in DLCO in 17 studies was the most common abnormality. Restrictive lung disease was seen in 11, an obstructive component in 1, and arterial hypoxemia at rest in 9 cases. Roentgenologic evidence of lung opacities, seen in 11 studies, was positively correlated (P<0.001) with decreases in DLCO. Arterial hypoxemia was significantly related to intrapulmonary right-to-left shunting (P<0.001) but not to DLCO indicating the importance of ventilation-perfusion abnormalities in the genesis of hypoxemia in these patients. Serial follow-up studies showed significant improvement in lung functions within 1 month (P<0.001) and complete resolution by 6 months in all survivors. The recovery was not related to the amount or duration of oxygen therapy or to the need for mechanical ventilation. Histopathologic studies in 9 patients who died during follow-up or subsequently did not indicate any residual interstitial fibrosis, collagen deposits and alveolopathy or vascular proliferation. We conclude that PCP in older children commonly does not result in long-lasting pulmonary sequelae.