Drug-resistant Mycobacterium tuberculosis among Nepalese patients at a tuberculosis referral center.

Background: Multidrug-resistant tuberculosis (MDR-TB), characterized by isoniazid and rifampicin resistance, is caused by chromosomal mutations that restrict treatment options and complicate tuberculosis management. This study sought to investigate the prevalence of pre-extensively drug-resistant (pre-XDR) and extensively drug-resistant (XDR) tuberculosis, as well as mutation pattern, in Nepalese patients with MDR/rifampicin-resistant (RR)-TB strains.

Methods: A cross-sectional study was conducted on MDR/RR-TB patients at the German Nepal Tuberculosis Project from June 2017 to June 2018.

Genome Sequences of Two Mycobacterium tuberculosis Isolates from Asian Elephants in Nepal.

This report describes the genome sequences of two Mycobacterium tuberculosis isolates, S1 and S3, recovered from Asian elephants in Nepal. These genome sequences will enhance our understanding of the genomic epidemiology of Mycobacterium tuberculosis in Asian elephants.

Comparison of Xpert MTB/RIF to Microscopy and Culture for the Diagnosis of Tuberculosis in a Referral Laboratory in Nepal.

Sputum microscopy and Xpert MTB/RIF are the primary rapid diagnostic methods for tuberculosis (TB) in Nepal. However, disagreements among Xpert, microscopy, and culture, for example, cases that are Xpert positive and microscopy negative, are frequently observed in Nepal, including in our reference laboratory. The objective of this study was to compare the effectiveness of Xpert with that of culture and microscopy for the diagnosis of TB in Nepal.

Rapid Tuberculosis Diagnostics Including Molecular First- and Second-Line Resistance Testing Based on a Novel Microfluidic DNA Extraction Cartridge.

Xpert MTB/RIF testing has improved tuberculosis (TB) diagnostics and rifampicin (Rif) resistance testing worldwide. However, it has weaknesses, such as its restriction to Rif resistance testing and the inability to use extracted DNA for further testing. Herein, a holistic diagnostic workflow, including TB detection and resistance testing toward Rif, isoniazid, and important second-line drugs (SLDs), based on a novel microfluidic DNA extraction cartridge (TB-Disk), is presented.

Molecular analysis of streptomycin-resistance associating genes in Mycobacterium tuberculosis isolates from Nepal.

Mutation in rpsL (encoding ribosomal protein S12), rrs (encoding 16S ribosomal RNA) and gidB (encoding 7-methylguanosine methyltransferase) are associated with resistance to streptomycin (STR), which is used for the treatment of multi-drug resistant tuberculosis (MDR-TB) in Nepal. The aim of our study is to analyze the correlation between mutations in the target genes and STR-resistance in 197 Mycobacterium tuberculosis (MTB) isolates from Nepal. Mutations in rpsL was harbored by 65.

Treatment outcomes of patients with MDR-TB in Nepal on a current programmatic standardised regimen: retrospective single-centre study.

Objectives: The objectives of this study were to evaluate treatment in patients on current programmatic multidrug-resistant tuberculosis (MDR-TB) regimen and verify eligibility for the 9-month regimen and therapeutic drug monitoring (TDM).

Methods: We performed a retrospective chart review of patients with MDR-TB receiving standardised regimen at the German Nepal TB Project Clinic, Nepal, between 2014 and 2016. Eligibility for the 9-month regimen and indications for TDM were evaluated.

Direct detection of Mycobacterium tuberculosis in clinical samples by a dry methyl green loop-mediated isothermal amplification (LAMP) method.

The purpose of this study was to develop a simple visual methyl green (MeG) based dry loop-mediated isothermal amplification (LAMP) method for early detection of Mycobacterium tuberculosis (MTB) from clinical samples. We identified MeG as an indicator of a positive LAMP reaction, where a positive reaction gave a blue-green color while a negative reaction was colorless. The MeG MTB-LAMP system was further simplified by drying all reagents for ease of use, and was then validated for its ability to diagnose TB directly using Nepalese clinical samples.

Mixed Mycobacterium tuberculosis Lineage Infection in 2 Elephants, Nepal.

Tuberculosis in elephants is primarily caused by Mycobacterium tuberculosis. We identified mixed M. tuberculosis lineage infection in 2 captive elephants in Nepal by using spoligotyping and large sequence polymorphism.

Evaluation of Saliva as a Potential Alternative Sampling Matrix for Therapeutic Drug Monitoring of Levofloxacin in Patients with Multidrug-Resistant Tuberculosis.

Saliva may be a useful alternative matrix for monitoring levofloxacin concentrations in multidrug-resistant tuberculosis (MDR-TB) patients. The objectives of this study were (i) to evaluate the correlation between plasma and salivary levofloxacin (Lfx) concentrations in MDR-TB patients and (ii) to gauge the possibility of using saliva as an alternative sampling matrix for therapeutic drug monitoring of Lfx in areas where TB is endemic. This was a prospective pharmacokinetic study that enrolled MDR-TB patients receiving levofloxacin (750- to 1,000-mg once-daily dosing) under standardized treatment regimen in Nepal.

Genetic diversity of Mycobacterium tuberculosis Central Asian Strain isolates from Nepal and comparison with neighboring countries.

Background: Multidrug-resistant tuberculosis (MDR-TB) is an emerging threat for successful tuberculosis control worldwide. Central Asian Strain (CAS) has been reported as one of the dominant families contributing to MDR-TB in South Asia including Nepal, India and Pakistan. The aim of this study was to better understand the genetic characteristics of MDR-TB CAS family isolates circulating in Nepal and compare the results with neighboring countries.

Genetic diversity and distribution dynamics of multidrug-resistant Mycobacterium tuberculosis isolates in Nepal.

Multidrug-resistant tuberculosis (MDR-TB) is an emerging public health problem in Nepal. Despite the implementation of a successful TB control program in Nepal, notifications of MDR-TB are increasing, yet the reasons are unknown. The objective of this study was to understand the genetic diversity and epidemiological characteristics of MDR-Mycobacterium tuberculosis (MTB) isolates in Nepal.

Tuberculosis in Staff and Students of Patan Hospital.

Background: There is a high risk of occupational exposure to tuberculosis among healthcare workers in endemic countries. Regular screening for tuberculosis among healthcare workers is not carried out in Nepal. Infection control measures are also not routinely implemented.

High diversity of multidrug-resistant Mycobacterium tuberculosis Central Asian Strain isolates in Nepal.

Objectives: Tuberculosis (TB) caused by Mycobacterium tuberculosis (MTB) poses a major public health problem in Nepal. Although it has been reported as one of the dominant genotypes of MTB in Nepal, little information on the Central Asian Strain (CAS) family is available, especially isolates related to multidrug resistance (MDR) cases. This study aimed to elucidate the genetic and epidemiological characteristics of MDR CAS isolates in Nepal.

Diagnostic Accuracy of GeneXpert MTB/RIF Assay in Comparison to Conventional Drug Susceptibility Testing Method for the Diagnosis of Multidrug-Resistant Tuberculosis.

Xpert MTB/RIF assay is regarded as a great achievement of modern medicine for the rapid diagnosis of multidrug-resistant tuberculosis (MDR-TB). The main purpose of this study was to determine the performance of Xpert MTB/RIF assay compared to conventional drug susceptibility testing (DST) method for the diagnosis of MDR-TB. A comparative cross sectional study was carried out at German-Nepal Tuberculosis Project, Kathmandu, Nepal, from April 2014 to September 2014.

A novel sputum transport solution eliminates cold chain and supports routine tuberculosis testing in Nepal.

This preliminary study evaluated the transport reagent OMNIgene SPUTUM (OMS) in a real-world, resource-limited setting: a zonal hospital and national tuberculosis (TB) reference laboratory, Nepal. The objectives were to: (1) assess the performance of OMS for transporting sputum from peripheral sites without cold chain stabilization; and (2) compare with Nepal's standard of care (SOC) for Mycobacterium tuberculosis smear and culture diagnostics. Sixty sputa were manually split into a SOC sample (airline-couriered to the laboratory, conventional processing) and an OMS sample (OMS added at collection, no cold chain transport or processing).

Molecular characterization of Mycobacterium orygis isolates from wild animals of Nepal.

Mycobacterium orygis, a new member of the Mycobacterium tuberculosis complex, was isolated from a captive spotted deer (Axis axis) and a blue bull (Boselaphus tragocamelus) in Nepal. Analyses by spoligotyping, mycobacterial interspersed repetitive units-variable number of tandem repeats (MIRU-VNTR) typing, region of difference and single nucleotide polymorphism of genes gyrB, mmpL6, TbD1, PPE55 and Rv2042c confirmed the isolates as M. orygis.

Molecular characterization of Mycobacterium tuberculosis isolates from elephants of Nepal.

Mycobacterium tuberculosis was cultured from the lung tissues of 3 captive elephants in Nepal that died with extensive lung lesions. Spoligotyping, TbD1 detection and multi-locus variable number of tandem repeat analysis (MLVA) results suggested 3 isolates belonged to a specific lineage of Indo-Oceanic clade, EAI5 SIT 138. One of the elephant isolates had a new synonymous single nucleotide polymorphism (SNP) T231C in the gyrA sequence, and the same SNP was also found in human isolates in Nepal.

Rapid Detection of Rifampicin and Isoniazid Resistant Mycobacterium tuberculosis Using Genotype MTBDRplus Assay in Nepal.

Rapid line probe assay (LPA) can be a practical and rapid alternative to the slow conventional phenotypic drug susceptibility testing (DST) for detection of drug resistant tuberculosis (TB). The purpose of this study is to determine the diagnostic accuracy of Genotype MTBDRplus, LPA for TB, and compare its performance with conventional DST. A total of 54 culture samples were analyzed for DST using both conventional proportion method and MTBDRplus, where conventional DST identified 43 isolates (79.

Simple multiplex PCR assay for identification of Beijing family Mycobacterium tuberculosis isolates with a lineage-specific mutation in Rv0679c.

The Beijing genotype of Mycobacterium tuberculosis is known to be a worldwide epidemic clade. It is suggested to be a possibly resistant clone against BCG vaccination and is also suggested to be highly pathogenic and prone to becoming drug resistant. Thus, monitoring the prevalence of this lineage seems to be important for the proper control of tuberculosis.

First insights into the phylogenetic diversity of Mycobacterium tuberculosis in Nepal.

Background: Tuberculosis (TB) is a major public health problem in Nepal. Strain variation in Mycobacterium tuberculosis may influence the outcome of TB infection and disease. To date, the phylogenetic diversity of M.

Characterization of extensively drug-resistant Mycobacterium tuberculosis in Nepal.

The emergence of extensively drug-resistant tuberculosis (XDR-TB) has raised public health concern for global control of TB. Although molecular characterization of drug resistance-associated mutations in multidrug-resistant isolates in Nepal has been made, mutations in XDR isolates and their genotypes have not been reported previously. In this study, we identified and characterized 13 XDR Mycobacterium tuberculosis isolates from clinical isolates in Nepal.

Molecular characterization of multidrug-resistant Mycobacterium tuberculosis isolated in Nepal.

Despite the fact that Nepal is one of the first countries globally to introduce multidrug-resistant tuberculosis (MDR-TB) case management, the number of MDR-TB cases is continuing to rise in Nepal. Rapid molecular tests applicable in this setting to identify resistant organisms would be an effective tool in reversing this trend. To develop such tools, information about the frequency and distribution of mutations that are associated with phenotypic drug resistance in Mycobacterium tuberculosis is required.