Ca-125: A Useful Marker to Distinguish Pulmonary Tuberculosis from Other Pulmonary Infections

INTRODUCTION: Ca-125 is secreted by different celomic epitheliums. Serum levels may be increased in malignant diseases, like ovarian cancer but also in other medical conditions, such as pulmonary and extrapulmonary tuberculosis. METHODS: From Jan-04 to Dec-06 a retrospective study analyzing Ca-125 levels in serum samples from patients with a diagnosis of pulmonary TB, was performed. These results were compared with those samples obtained from patients with non-TB pulmonary infections. RESULTS: Eighty-nine patients were included in the study, thirty-five with pulmonary TB and 54 with other respiratory infections. In patients with TB, the mean Ca-125 value was 104.9 IU/ml (SD: ± 136.1). In the control group, mean value was 27.1 IU/ml (SD: ±19.7). The optimal cut-off for pulmonary tuberculosis was 32.5 IU/ml (sensitivity: 68.6%, specificity: 77.8%). Pulmonary TB was the only factor associated with a Ca-125 level >32.5. In 10 patients with TB, Ca-125 levels were available ≥ 2 months after starting TB therapy and a decrease during treatment was shown. CONCLUSIONS: Ca-125 values increase in patients with pulmonary TB and decline to normal values during treatment. Determination of Ca 125 may be usedin patients with a negative sputum AFB stain.