Sensitivity of PCR IS6110 in relation to culture and staining in Pott’s disease

Abstract

Background Rapid diagnosis is essential to decrease the morbidity and mortality of Pott’s disease. The bacteriological methods are time-consuming or insensitive. Polymerase chain reaction (PCR) provides a rapid diagnostic tool and hope for early diagnosis of this disease. The aim of this study was to compare and assess of a rapid and effective method among diagnostic battery (Ziehl–Neelsen (ZN) microscopy, BACTEC culture and PCR) of Pott’s disease. Materials and Methods Sixty-five specimens from clinico-radiological suspected cases of Pott’s disease were included in this study. They were processed for ZN microscopy, BACTEC culture, and PCR IS6110. The tests tool’s efficiency, positive agreement K c (Kappa coefficient), and significance level (P value) were calculated for correlation between PCR and performed tests. Results The PCR sensitivity reached to 96% and 46.3% among positive and negative specimens on ZN microscopy. Further, 94% and 36.4% sensitivity were found among positive and negative specimens by BACTEC culture. The total 38 (58.5%) specimens were detected either ZN microscopy or by BACTEC culture. Thus, the overall sensitivity and specificity of PCR were 95% and 74.1%. The kappa coefficient and P value, calculated for PCR against BACTEC culture and combined results of performed bacteriological tests were (K c=0.60, (P<0.001)) and (K c=0.70, (P<0.001)), respectively. Above statistical relations showed a fair agreement with significant differences. Conclusion The PCR IS6110 may be useful in rapid detection of clinico-radiological suspected cases of Pott’s disease and those that are negative with bacteriological methods.

Keywords

• m. tuberculosis
• polymerase chain reaction is6110
• pott’s disease and kappa coefficient