THE RELATION OF EXHALED BREATH CONDENSATE "PH" WITH SMEAR POSITIVITY, ACUTE PHASE REACTANTS AND RADIOLOGICAL EXTENT OF DISEASE IN SMEAR POSITIVE PULMONARY TUBERCULOSIS

Introduction: Exhaled breath condensate (EBC) pH has been shown to be a good indicator of inflammation in the airways in several pulmonary diseases. Bronchial inflammation is an expected condition also in pulmonary tuberculosis and may play role in the extent of parenchymal infiltration. It is conceivable that EBC pH may be an useful marker in demonstrating the extent of airway inflammation in tuberculosis patients; however, there is limited clinical data about its role in pulmonary tuberculosis. In this prospective study we aimed to investigate the inflammation of the airways by EBC pH and to evaluate the relationship between the degree of smear positivity and the radiological extent of tuberculosis. Materials and methods: 19 untreated smear positive pulmonary tuberculosis cases and 31 healthy controls were included in the study. While the control group was investigated for only EBC pH, the patient group was investigated for EBC pH, chest X-ray, serum procalcitonin level and acido-alcohol resistant bacilli examination in sputum smear. Available parameters were compared statistically between healthy controls and patients. Results: Mean EBC pH was found to be significantly low in tuberculosis group (p <0.001). In the patient group, there was a moderate negative correlation between EBC pH and ARB positivity (p <0.02), moderate positive correlation between serum procalcitonin and erythrocyte sedimentation rate (p <0.02), moderate positive correlation between serum procalcitonin and radiological extent (p <0.008), a strong positive correlation between erythrocyte sedimentation rate and radiological extent (p <0.003). However, any statistically significant correlation was not observed between EBC pH and radiological extent. Conclusion: In this study it has been demonstrated that EBC pH was in association with pulmonary inflammation in tuberculosis and smear positivity but had no relationship with parenchymal infiltration. On account of this, we state that EBC pH may be useful in the assessment of the airway inflammation and bacillary load, but is not a good predictor of radiological extent of pulmonary tuberculosis.