FIBRINOLYTIC ACTIVITY IN LUNG TISSUE FROM NEONATES WITH HYALINE MEMBRANE DISEASE

The fibrinolytic activity of lung tissue was studied with Todd's histochemical method in a material of 29 newborn infants containing normal lungs, hyaline membrane disease, atelectasis and massive pulmonary haemorrhage. No significant difference was found between a group of hyaline membrane lungs and a group of atelectatic lungs without hyaline membranes. In one case with massive pulmonary haemorrhage the activity was high. Our findings make it questionable whether a lack of plasminogen activator in the lung of infants with hyaline membrane disease is a consistent finding and argue against an alteration of the intrapulmonary fibrinolytic system being of any major importance in the formation of the membranes.