br Experiment br Results and discussion br Conclusion br Int

Experiment
Results and discussion
Conclusion
Introduction Tuberculosis (TB) is a chronic specific bacterial infection caused by bacteria of the Mycobacterium tuberculosis [1]. TB remains one of the deadliest diseases in the world. It is the second leading infectious cause of death after Human Immunodeficiency Virus (HIV) infection [2]. It is an ancient disease with the evidence of the organism being present in skeletons over 4000years ago [3]. The earliest records that are consistent with tuberculosis are the Egyptian wall paintings that described the typical hunchback deformities and correlate with the findings of spinal tuberculosis in mummies [4], [5]. Adenosine deaminase (ADA) is an enzyme involved in purine catabolism, the enzyme catalyzes the hydrolytic and irreversible deamination of adenosine to inosine and deoxyadenosine to deoxyinosine [5]. ADA has been extensively used in the diagnosis of tuberculous pleural effusion, two isoenzymes, ADA1 and ADA2, have been described [6]. In humans two different isozymes are encoded by different genes, ADA1 is a single-chain Zn-binding protein and almost all activities are attributed to this protein. ADA2 is believed to be produced by monocytes and is found in negligible quantities. Mutations in the ADA1 gene, where SecinH3 is blocked, cause immunodeficiency, whereas mutations that cause overexpression cause hemolytic anemia [5]. Few studies have investigated the use of ADA activity in material other than pleural fluid. There are conflicting data regarding the use of ADA activity in bronchoalveolar lavage (BAL) as a diagnostic tool in pulmonary TB. Moreover, patients may have relative contraindications that make bronchoscopy difficult to carry out, whereas sputum is easily obtainable. However, sputum may be AFB-negative even in the presence of the disease [6].
Subjects and methods Group I: 15 patients diagnosed as active pulmonary tuberculosis. All patients had symptoms and signs of active pulmonary tuberculosis, positive sputum smear for acid fast bacilli, with X-ray findings consistent with active pulmonary tuberculosis. Group II: 15 patients diagnosed as pneumonia. All patients had symptoms and signs of pneumonia, with X-ray findings consistent with pneumonia and consolidation. Group III: 15 patients diagnosed as bronchogenic carcinoma. All patients had symptoms and signs of bronchogenic carcinoma, with X-ray, CT and histopathological findings consistent with bronchogenic carcinoma. Sputum smears for acid-fast bacilli: Early morning expectorated sputum specimens obtained after a deep, productive cough were collected on three days from each patient in a clean tightly closed plastic disposable container properly labeled and stained with Ziehl–Neelsen stain, quantitation scale for acid fast bacillus smears was done [7]. Measurement of serum and sputum ADA in all patients [8]: Early morning sputum samples and 5cc venous blood samples were obtained from all patients. Blood samples were centrifuged at 3500rpm for 10min to separate the sera. Sputum samples were homogenized with 70milli-mol phosphate buffer (pH: 6.0) containing 0.5mol NaCl (1ml sputum+5ml buffer). They were centrifuged at 5000rpm for 30min and ADA activity of the supernatant was measured by Gusti method. Results were corrected by multiplying with the dilution coefficient. All reagents stored at 2–8°C with valid period: six months for samples like: Cell culture fluid & body fluid & tissue homogenate Serum or blood plasma and for 96 tests. Reagents handling: ADA reagent came in a liquid two reagent system ready to use for both manual and automated analyzer method. ADA controls and calibrator are in lyophilized form, and need to be reconstituted with 1.0 of DI water before use. Assay procedure: ADA kit was used on automated clinical chemistry analyzers. Calibration: 0.9% saline and ADA calibrator were needed for calibration. Results: The ADA results were printed out in U/L.