NESTED POLYMERASE CHAIN-REACTION FOR DETECTION OF MYCOBACTERIUM-TUBERCULOSIS IN SOLITARY PULMONARY NODULES

Background: Differential diagnosis of solitary pulmonary nodules (SPNs ) can be difficult in areas, such as Korea, where tuberculosis is ende mic, Nested polymerase chain reaction (PCR) is a widely used method to test a very small amount of pathogen and to detect Mycobacterium tube rculosis from fine needle aspirates, Objectives: The usefulness of nes ted PCR for the detection of M tuberculosis from tuberculous SPN and f or the differential diagnosis of SPN was evaluated, Methods: Thirty-th ree patients in whom a diagnosis of SPN was made based on a CT scan of the chest were enrolled in this study Included were 17 malignant and 16 benign SPNs. Nested PCR was carried out for the detection of M tube rculosis by using TB-1, TB-2, TB-28, and TB-29C on fine needle aspirat es from the nodule in all 33 cases, Results: Aspirates from malignant neoplasms, pneumonia, and sequestration were all negative on nested PC R for tuberculosis. One of the three radiologically suspected tubercul ous nodules without response to anti-tuberculosis drugs (uncertain) yi elded positive results on nested PCR for the detection of M tuberculos is, In contrast, 7 out of 8 (87.5%) aspirates from proven tuberculous nodules showed positive results on nested PCR, Nested PCR could be use d to detect M tuberculosis in fine needle aspirates from tuberculous S PNs with good sensitivity (87.5%) and specificity (96.0%). Conclusion: Nested PCR for the detection of M tuberculosis in fine needle aspirat es may be useful in the differential diagnosis of SPNs.