02331nas a2200337   4500000000100000008004100001260001300042653001100055653001200066653002500078653003000103653001900133653002400152653003200176653000900208100001900217700001800236700002100254700001700275700001900292700001500311700002400326700001500350700001800365245011000383856007000493300001100563490000700574520139800581022001401979       2008                            d  c2008 Nov10aHumans10aleprosy10aMycobacterium leprae10apolymerase chain reaction10aRNA, Bacterial10aRNA, Ribosomal, 16S10aSensitivity and Specificity10aSkin1 aRudeeaneksin J1 aSrisungngam S1 aSawanpanyalert P1 aSittiwakin T1 aLikanonsakul S1 aPasadorn S1 aPalittapongarnpim P1 aBrennan PJ1 aPhetsuksiri B00aLightCycler real-time PCR for rapid detection and quantitation of Mycobacterium leprae in skin specimens.  uhttp://femsim.oxfordjournals.org/content/femsim/54/2/263.full.pdf  a263-700 v543 a<p>Diagnosis of leprosy is usually based on clinical features and skin smear results including the number of skin lesions. Mycobacterium leprae is not cultivable and bacterial enumeration by microscopic examination is required for leprosy classification, choice in choosing and monitoring chemotherapy regimens, and diagnosis of relapse. However, detection and quantification using standard microscopy yields results of limited specificity and sensitivity. We describe an extremely sensitive and specific assay for the detection and quantification of M. leprae in skin biopsy specimens. Primers that amplified a specific 171-bp fragment of M. leprae 16S rRNA gene were chosen and specificity was verified by amplicon melting temperature. The method is sensitive enough to detect as low as 20 fg of M. leprae DNA, equivalent to four bacilli. The assay showed 100% concordance with clinical diagnosis in cases of multibacillary patients, and 50% of paucibacillary leprosy. The entire procedure of DNA extraction and PCR could be performed in c. 3 h. According to normalized quantitative real-time PCR, the patients in this study had bacilli numbers in the range of 1.07 x 10(2) -1.65 x 10(8) per 6-mm3 skin biopsy specimen. This simple real-time PCR assay is a facile tool with possible applications for rapid detection and simultaneous quantification of leprosy bacilli in clinical samples.</p>  a0928-8244