Abstract
Traditional histological diagnosis of tuberculosis with Ziehl-Neelsen acid fast stain is insensitive and poorly specific. To improve this, we introduced the nested polymerase chain reaction (PCR) protocols to detect the M. tuberculosis complex-specific insertion sequence IS6110 in formalin-fixed paraffin-embedded (FFPE) sections. Trials were performed on tissues from 14 patients with suspicious histological diagnoses of tuberculosis. 8 (57.1%) of these cases were positive for M. tuberculosis complex DNA; otherwise Ziehl-Neelsen stain detected mycobacterium in only 2 cases (14.3%). In conclusion, nested PCR assays can be used as reliable tools for the detection of M. tuberculosis infections in FFPE tissues and show improved sensitivity and specificity compared to traditional histological assay.
