[Levels of CEA, antibodies against mycobacterial antigens and ACE activity in serum and in BALF in patients with sarcoidosis, tuberculosis and lung cancer--preliminary results].
UNLABELLED: Assessment of CEA concentration, levels of the antibodies against mycobacterial antigens A60 and 38 kDa and ACE activity in serum and in BALF of the patients with sarcoidosis (n = 8), tuberculosis (n = 13) and lung cancer (n = 10) was performed. Nine healthy volunteers were referred to as the control group. Sarcoidosis and lung cancer were confirmed histopathologically. Diagnosis of tuberculosis was stated using the radiometric Bactec 460 system. Serum and BALF CEA concentration and IgG levels against A-60 and 38 kDa were measured by ELISA: IMx, Immunozym and Pathozyme, respectively. ACE activity was assayed by the spectrophotometric method. Statistically significant (p < 0.01) increase in BALF-ACE activity in patients with sarcoidosis compared to each group was observed. Serum level of antibodies against 38 kDa and serum ACE activity were specific for tuberculosis and sarcoidosis respectively, but their sensitivity were very poor. Serum CEA concentration was fairly specific for lung cancer but its sensitivity was not satisfactory. CONCLUSIONS: 1. Determination of BALF-ACE activity may be helpful in diagnosis of sarcoidosis but it is recommended to continue the study on more numerous groups of patients taking into consideration polymorphism in the ACE gene. 2. High level of antibodies against 38 kDa and ACE activity in serum are specific for tuberculosis and sarcoidosis respectively but both tests have restricted application because of their poor sensitivity. 3. Serum CEA concentration could be considered only as an auxiliary test in the diagnosis of lung cancer.