Abstract: | Persistent pulmonary hypertension of the newborn is a syndrome consisting of severe hypoxemia and pulmonary hypertension that appears within hours of birth. Since certain leukotrienes (C4, D4, and E4) are known to produce some of the features of persistent pulmonary hypertension of the newborn, including pulmonary vasoconstriction, bronchoconstriction, decreased lung compliance, and pulmonary edema, we studied five newborns with the syndrome to determine whether these leukotrienes were present in their airways. We found leukotriene C4 and leukotriene D4 in the lung lavage fluids of all five newborns who had the clinical diagnosis of persistent pulmonary hypertension and who required ventilatory assistance. In contrast, leukotrienes were not demonstrated in a control group of 14 infants requiring ventilatory assistance who did not have the clinical diagnosis of persistent pulmonary hypertension. We conclude that leukotrienes may have a role in persistent pulmonary hypertension of the newborn. |