Diagnosis of Pulmonary Tuberculosis by Measurement of ADA, CEA and PCR in Bronchoalveolar Lavage and Compare with Smear and Culture of BK in the Patient with Pulmonary Infiltration

Background: Pulmonary tuberculosis ( TB) is one of the problems in diagnosis and management of patients with pneumonia and pleural effusion. Bronchoscopy and bronchoalveolar lavage (BAL) can help us in the differential diagnosis. Tumor markers are substances that are produced by cancer or other cells of the body in response to diseases. These substances can be found in the blood, urine, or body fluids, for example in bronchoalveolar lavage of some patients with pulmonary diseases. CEA is a tumor marker that can help us for diagnosis and monitoring of peripheral lung cancer. ADA has been shown to rise in the BAL of patients with TB. Because the sputum smear negative TB patients have been a diagnostic challenge for health professionals this study was designed to determine the diagnostic value of ADA & CEA & PCR in BAL fluid and then compare the relationship of these markers with sputum and clinical finding in diagnosis of pulmonary tuberculosis. Material and Method: A cross sectional study conducted in Shahrekord Hajar hospital where 100 patients were enrolled in our study (62 females, 38 males). These patients were admitted to hospital and bronchoscopy with BAL was performed, then fluid was analysed for ADA, CEA, PCR and sputum smear for TB. Result: From 100 patients who were evaluated in this study 9 patients had TB, 39 patients had pneumonia, 11 patients had primary lung malignancy, 9 patients had metastases to lung and 8 patients had bronchitis. In Patients with TB the level of ADA was not significantly elevated in BAL. ADA increased significantly in patients with pneumonia (P: 0/95). In patients with metastases to lung and primary lung cancer and a combination of both groups compared to other patients without malignancy there was no relationship between CEA. PCR was positive in TB and other patients, but significantly increased in TB. (p=0/021) Discussion: Although it was thought that CEA may be elevated in BAL of patients with malignancy and ADA in tuberculosis we did not find a correlation in these patients. This study showed that ADA and CEA levels in BAL fluid does not help us in diagnosis of TB or cancer. It may have afalse positive in pneumonia, COPD and other diseases, but PCR for TB may assist in TB diagnosis but not alone.