Clinicians working with HIV patients know how difficult it is to make a certain tuberculosis diagnosis in the smear negative pulmonary tuberculosis. Often the diagnosis is made on clinical and radiological criteria, and is based on national guidelines and international recommendations.
In a recent paper in PLoSONE, Davies and colleagues show that Clinical and radiographic criteria did not help diagnose smear-negative pulmonary tuberculosis among HIV-infected patients with unexplained cough in a low-income setting.
In their paper they evaluated if commonly used clinical and radiological signs could predict if the patient had tuberculosis, and they used culture as their god standard for diagnosing a definite tuberculosis diagnosis. However, their paper does not discuss the limits in doing cultures, and their samples might not have been representative.
In a recently research from south Ethiopia we found that patients receiving antituberculosis drugs had better survival than patients without tuberculosis. This unexpected finding may be because many patients remain undiagnosed with tuberculosis. In the Arba Minch Hospital Cohort Study we evaluated the survival of 1428 patients receiving antiretroviral treatment over a six-year period.
It further underlines Davis’s recommendation that we need improved tools to diagnose smear-negative tuberculosis in developing countries.
Davis, J., Worodria, W., Kisembo, H., Metcalfe, J., Cattamanchi, A., Kawooya, M., Kyeyune, R., den Boon, S., Powell, K., Okello, R., Yoo, S., & Huang, L. (2010). Clinical and Radiographic Factors Do Not Accurately Diagnose Smear-Negative Tuberculosis in HIV-infected Inpatients in Uganda: A Cross-Sectional Study PLoS ONE, 5 (3) DOI: 10.1371/journal.pone.0009859