The International Journal of Mycobacteriology

ORIGINAL ARTICLE
Year
: 2020  |  Volume : 9  |  Issue : 1  |  Page : 18--23

Dominant marker (inter-simple sequence repeat-polymerase chain reaction) versus codominant marker (RLEP-polymerase chain reaction) for laboratory diagnosis of leprosy: A comparative evaluation


Partha Sarathi Mohanty1, Avi Kumar Bansal1, Farah Naaz1, Shripad A Patil1, Mamta Arora1, Manjula Singh2 
1 Department of Epidemiology, National JALMA Institute for Leprosy and Other Mycobacterial Diseases, Agra, Uttar Pradesh, India
2 Division of Epidemiology and Communicable Diseases, Indian Council of Medical Research, New Delhi, India

Correspondence Address:
Partha Sarathi Mohanty
Department of Epidemiology, National JALMA Institute for Leprosy and Other Mycobacterial Diseases, M. Miyazaki Marg, Tajganj, Agra, Uttar Pradesh
India

Background: Leprosy is a contagious disease and was eliminated globally in 2002. Since then, new cases were continuously detected from different parts of the world. Untreated leprosy cases shed millions of bacteria and are the main cause of dissemination of the disease. Currently, leprosy is detected by acid-fast bacilli (AFB) microscopy and has a low sensitivity ranging from 10% to 50%. The correlation between clinical findings and microscopy is unable to provide a conclusive case detection. Thus, in the present study, we compared to molecular methods, namely RLEP-polymerase chain reaction (RLEP-PCR) and inter-simple sequence repeat-PCR (ISSR-PCR) taking AFB microscopy as a gold standard for the detection of leprosy. Methods: A total of 168 clinically diagnosed leprosy patients were recruited in this study including 58 multibacillary and 110 paucibacillary patients. Slit-skin smear samples were taken for both microscopy and molecular study. Primers for RLEP-PCR were taken from the previous reports. The primers for ISSR-PCR were designed by screening the whole genome of Mycobacterium leprae TN strain (GenBank accession AL450380) for the presence of simple sequence repeats. One primer (TA)8CA3was synthesized and used for molecular amplification of ISSR-PCR. Results: We found that the efficacy of the AFB microscopy was 24.40%, whereas the efficacy of RLEP-PCR and ISSR-PCR was 63.09% and 73.21% (P = 0.000, 0.000, and 0.469), respectively. The area under the curve of receiver operating characteristic curve for the comparison of three diagnostic methods was 0.845. An enhancement of 48.81% in the case detection rate by ISSR-PCR over AFB microscopy and 10.12% over RLEP-PCR was also found. Our study clearly reveals that ISSR-PCR is a better tool for diagnosis of leprosy than AFB microscopy and RLEP-PCR. Interestingly, both the PCR techniques RLEP-PCR and ISSR-PCR are able to detect samples which were negative for AFB microscopy. Conclusion: Thus, the demonstration of ISSR-PCR in SSS samples can provide a better sensitive and confirmative tool for early diagnosis of leprosy.


How to cite this article:
Mohanty PS, Bansal AK, Naaz F, Patil SA, Arora M, Singh M. Dominant marker (inter-simple sequence repeat-polymerase chain reaction) versus codominant marker (RLEP-polymerase chain reaction) for laboratory diagnosis of leprosy: A comparative evaluation.Int J Mycobacteriol 2020;9:18-23


How to cite this URL:
Mohanty PS, Bansal AK, Naaz F, Patil SA, Arora M, Singh M. Dominant marker (inter-simple sequence repeat-polymerase chain reaction) versus codominant marker (RLEP-polymerase chain reaction) for laboratory diagnosis of leprosy: A comparative evaluation. Int J Mycobacteriol [serial online] 2020 [cited 2020 May 30 ];9:18-23
Available from: http://www.ijmyco.org/article.asp?issn=2212-5531;year=2020;volume=9;issue=1;spage=18;epage=23;aulast=Mohanty;type=0