In developing nations the frequency in using PCR for the diagnosis of tuberculosis is continuously increasing in the routine diagnostic laboratories. The technique is now being accepted as the assay is being upgraded with the incorporation of additional reagents, chemicals, bio-molecules to remove very common contaminant i.e. amplicons. Study includes 125 CSF specimens processed simultaneously by Nested PCR utilising Uracil-N-Glycosylase enzyme and conventional PCR targeting IS6110. It has been seen that using conventional PCR, the frequency of getting false result due to amplicons were more as compared to nested PCR utilizing UNG which degraded the previous amplicons generated. Nested PCR for tuberculosis detection is a better tool when incorporated with an addition of UNG to prevent amplicon contamination. False positive cases by amplicon contamination can be prevented by UNG and dUTP instead of dTTP, during master mix preparation. The skill set required to adequately treat critically ill patients will also require knowledge of molecular biology for better diagnosis and treatment. Amplicon contamination detection and its prevention is of critical importance where the results interpretations are directly involved with patient’s health.
