Clinical Study of Lower-Lung Field Tuberculosis

Background: Lower lung field tuberculosis is atypical presentation of pulmonary tuberculosis which often causes confusion in diagnosis. HIV/AlDS epidemic has considerably increased its incidence. This study was designed to identify the prevalence and different clinical conditions of lung tuberculosis in conjunction with its common clinical and radiological presentations and its treatment. Methods: The patients diagnosed as having pulmonary tuberculosis with lesions below an arbitrary line across the hila of their chest X-rays, considered lower lung field tuberculosis, are included in this study. Laboratory testing was done on sputum for acid-fast bacillus. HIV testing, blood sugar and other relevant examinations were performed in each patient. Results: Out of a total of 2 I7 patients with pulmonary tuberculosis, J9.8% had lower lung field tuberculosis. The majority of the patients (41.8 0/ 0) were over 60-yrs of age. It was more common in female (21.8%) than in male patients (J 7.7%). Unilateral disease was more common (52%) and the right side involvement was more frequently affected (60%). Consolidation (47%) and cavitations (26%) were the main radiological findings. Conclusion: Lower lung field tuberculosis is fairly common in central part of Iran. Its clinical presentation is similar to that of classical upper lung field tuberculosis