Phospholipase activities of bronchoalveolar lavage fluid in rat Pneumocystis carinii pneumonia.

Respiratory distress, main clinical symptom of P. carinii pneumonia, is unexplained. We wondered if it could be linked with a lung surfactant anomaly. We have shown in the bronchoalveolar fluid lavage of P. carinii-infected rats: a very significant decrease of the phospholipid content; a lowering of the phospholipid/protein ratio; and an increase in phospholipase activities, partly due to the activation of an inactive phospholipase into the active form. We conclude that, in P. carinii-infected rats, there is an increased catabolism of lung surfactant.