Genomic characterization of Mycobacterium lepromatosis from ENL patients from India.

BACKGROUND: Leprosy is caused by Mycobacterium leprae and Mycobacterium lepromatosis. Both organisms cannot be cultured in vitro. M. lepromatosis was found to be associated mainly with diffuse lepromatous leprosy and with Lucio's phenomena initially. Later, M. lepromatosis was observed in borderline leprosy cases (BL), lepromatous leprosy cases (LL) and leprosy reactional cases (T1R and ENL). Although many cases are being reported with similar clinical features like Lucio phenomenon in India but M. lepromatosis was not isolated from these cases. The aim of this study was to screen MB patients and patients with type 2 reaction for the presence of M. lepromatosis. METHODOLOGY: We recruited a total of 75 multibacillary leprosy cases (45 MB cases without reaction and 30 type 2 reaction (ENL) cases) from TLM hospitals Purulia (West Bengal), Barabanki (Uttar Pradesh), Shahdara (Delhi) and PGIMER (Chandigarh), India. Punch biopsies of 5 mm were collected in 70% ethanol from all the study subjects. DNA was extracted followed by Hemi-nested PCR targeting 16S rRNA gene specific for M. lepromatosis. Further, PCR products were processed for Sanger sequencing for an absolute confirmation of M. lepromatosis. Whole genome sequencing was done to confirm the presence of M. lepromatosis. RESULT: We observed presence of M. lepromatosis in 4 necrotic ENL patients by heminested PCR. There was 100% 16S rRNA sequence similarity with M. lepromatosis FJ924 in one case, 98.96% in two cases and in one case it was 90.9% similarity by nucleotide BLAST (BLASTn) by using the NCBI website. On the basis of Sanger sequencing, we noted presence of M. lepromatosis in 3 necrotic ENL patients as one sample only gave 90.9% similarity by BLASTn. On the basis of de novo assembly and genome obtained, only one sample S4 with a 2.9 mb genome size was qualified for downstream analysis. Sixteen M. lepromatosis- specific proteins were identified in this case and the closest species was M. lepromatosis strain FJ924 based on whole genome level phylogeny. CONCLUSION: These results provide valuable insights into the prevalence of M. lepromatosis in ENL patients in different regions of India and contribute to our understanding of the genetic characteristics of this pathogen in the context of leprosy.

Mycobacterium Indicus Pranii (MIP) Vaccine: Pharmacology, Indication, Dosing Schedules, Administration, and Side Effects in Clinical Practice.

Mycobacterium indicus pranii (MIP), previously called Mw vaccine, is a one-of-a-kind immunomodulatory vaccine. It was indigenously developed in India for use in leprosy. MIP is heat-killed Mycobacterium w, which is a non-pathogenic atypical mycobacterium belonging to Class IV of Runyon classification. It shares epitopes with Mycobacterium leprae and Mycobacterium tuberculosis, which forms the rationale behind its use in leprosy and tuberculosis. MIP activates both innate and acquired immunity. It induces a Th1 and Th17 immune response along with downregulation of Th2 pathway and activates macrophages and dendritic cells. MIP vaccine is safe with adverse effects such as local site erythema, swelling, and rarely fever and other systemic reactions. Apart from leprosy, MIP has been used in dermatological diseases such as warts and psoriasis. Clinical trials have evaluated the efficacy of MIP in a plenitude of non-dermatological conditions such as category II tuberculosis, Gram-negative sepsis, non-small cell lung cancer, human immunodeficiency virus (HIV), muscle-invasive bladder cancer, and very recently, coronavirus 2019 (COVID-19). In vitro and animal studies have also demonstrated its utility in leishmaniasis, melanoma, and as a vaccine for the prevention of pregnancy. The PubMed database was searched using "Mycobacterium indicus pranii, MIP, Mycobacterium w" as the keyword in title. This comprehensive review provides useful information for healthcare professionals about immunotherapeutic potential of MIP vaccine, its composition, dosing schedule, administration, and side effects besides its efficacy in various indications other than leprosy.

High frequency of ofloxacin resistance patterns of Mycobacterium leprae from India: An indication to revisit second line anti-leprosy treatment regimen.

OBJECTIVES: Drug resistance in leprosy is an emerging concern, leading to treatment failures, recurrences, and potential spread of resistant Mycobacterium leprae in the community. In this study, we aimed to assess drug resistance prevalence and patterns amongst leprosy patients at a tertiary care referral hospital in India. METHODS: Mutations in drug resistance determining regions for dapsone, rifampicin, and ofloxacin of the M. leprae genome in DNA extracted from skin biopsies of 136 leprosy patients (treatment-naive = 67, with persistent skin lesions = 35, with recurrence = 34) were analysed by polymerase chain reaction followed by Sanger sequencing. Wild-type strain (Thai-53) was used as a reference strain. RESULTS: Resistance mutations were identified in a total of 23 patients, constituting 16.9% of the cohort. Within this subset of 23 cases, resistance to ofloxacin was observed in 17 individuals (12.5%), while resistance to both dapsone and rifampicin was detected in three patients each (2.2% for both). The occurrence of ofloxacin resistance showed minimal disparity between recurrent and treatment-naive cases, at 17.6% and 16.4%, respectively. Dapsone resistance emerged in two treatment-naive cases and one case with persistent skin lesions. Notably, none of the treatment-naive cases or those with recurrence/relapse exhibited rifampicin resistance. Subsequently, no statistically significant correlation was identified between other clinical variables and the presence of antimicrobial resistance. CONCLUSIONS: The occurrence of resistance to the current multidrug therapy regimen (specifically dapsone and rifampicin) and to ofloxacin, a secondary antileprosy medication in M. leprae, represents a concerning scenario. This calls for an expansion towards bactericidal drug options and the establishment of robust surveillance for drug resistance in countries burdened with high leprosy rates. Moreover, the introduction of stringent antimicrobial stewardship initiatives is imperative. As a single centre study, it represents a limited, cross-sectional view of the real situation in the field.