Study of respiratory symptoms among sputum positive

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Diagnosis of pulmonary TB
The diagnosis of pulmonary tuberculosis is not easy. Clinical signs
are non specific and may be confused with many chest diseases.
Radiological changes increase the suspicion of pulmonary tuberculosis.
Examination of the sputum smear is helpful and has a high positive
predictive value (Gordin, 1990).
• Chest radiograph in pulmonary TB
The chest radiograph remains the most widely used and the most
valuable tool in the diagnosis of pulmonary TB. Radiographic findings
accurately reflect the pathologic process that occurs in the development of
primary and reactivation TB (try TB traditionally been a disease ofinfants
and children) (Bloch et aI., 1989).
In patients who have signs and symptoms suggesting pulmonary TB
standard posterior-anterior and lateral radiograph of the chest should be
obtained. Apical, lordotic or oblique views may aid in visualizing lesions
obscured by bony structures and the heart. Bronchography may be useful in
the definition of bronchial stenosis or bronchiactasis (Bass et aI., 1990).
The traditional appearance ofreactivation TB in the chest is a focal
infiltrate and/or cavity in the apical or posterior segment ofan upper lobe
or perhaps in the superior segment ofa lower lobe. While these traditional
concepts of TB are still valid, a significant change in the pattern of
pulmonary TB has occurred in the past 30 years, with a much greater
incidence of primary TB in adults. This change was first pointed out in
1977, that noted a high incidence of nontraditional radiographic finding in
adults with TB (Khan et aI., 1977). These non traditional findings reflected
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