Kininase I and II activities in serum of patients with lung diseases.
In serum of 530 patients with various lung diseases and in 70 healthy control subjects, kininase I (E.C. 3.4.17.3) and kininase II (E.C. 3.4.15.1) were measured spectrophotometrically using hippuryl-L-arginine for estimation of kininase Ia (KIa), hippuryl-L-lysine for kininase Ib (KIb) and hippuryl-L-histidyl-L-leucine for kininase II (KII). KIa and KIb were significantly elevated (p less than 0.02) in lung cancer and sarcoidosis, compared to tuberculosis and healthy controls. There was an increase (p less than 0.05) in lung cancer in relation to sarcoidosis, chronic obstructive bronchitis, tuberculosis, pulmonary fibrosis and healthy control subjects. KII was significantly elevated in sarcoidosis (p less than 0.0001). According to the histological types of lung cancer, no differences of KIa, KIb and KII have been found. The ratio KIa/KIb X KII was 2.3 in lung cancer and 6.7 in the group with sarcoidosis. These results show that the determination of kininases can be used for diagnosis of lung diseases.