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Background: Drug-resistant tuberculosis (DR-TB) is difficult to treat, and its timely diagnosis is an important factor in successful treatment outcomes. Modern technology has made it possible to diagnose DR-TB more quickly than before when it took a long time to identify the presence of resistance Mycobacterium. Objective: To evaluate the efficacy of the Xpert MTB/XDR to test the susceptibility of MTB towards anti-TB drugs by using sputum samples from infected people. Methodology: A cross-sectional study was conducted at the Programmatic Management of Drug-Resistant TB Unit (PMDT), Lady Reading Hospital, Peshawar, from March 2021 to March 2023. This study included samples from patients identified as rifampicin-resistant patients. The Xpert® MTB/XDR test's diagnosis accuracy was compared to that of the MGIT960, the reference drug susceptibility testing (DST) techniques, and the Hain Genotype® MTBDR plus and MDRsl assays (LPA). Results: The present study included 180 patients. These patients were divided into three groups for study purposes based on technique used, i.e., Pre-LPA or DST, Post-LPA, and Ten color Xpert MTB/XDR, and followed up for their culture conversion. Gene-Xpert MTB/RIF showed 93% of cases were positive, and on DST all cases showed positive results. For drug resistance in DST, LPA, and Gene-Xpert MTB/XDR, 61.1% of patients were resistant to three first-line drugs, and 11.1% were resistant to the second line. The overall median time from the identification of patients suspected of MDR-TB to the initiation of treatment in DST was 93 days. In LPA it was 25 and 5 days by Ten color Gene Xpert MTB/XDR. Conclusion: This study concludes that based on the timely initiation of treatment and culture conversion reports, DST and LPA are less efficient than the Ten-color Gene Xpert MTB/XDR assay. [ABSTRACT FROM AUTHOR]

Background: Pakistan ranks fourth among the 22 high-burden countries for multidrug-resistant tuberculosis (MDR-TB). The rising incidence of MDR-TB highlights the need for effective treatment programs, as the clinical management of MDR-TB involves prolonged multidrug regimens that frequently result in adverse events (Aes). Objective: This study aims to determine the frequency of treatment-related adverse events among patients enrolled in MDR-TB treatment. Methodology: We conducted a retrospective case series study involving patients enrolled for MDR-TB treatment from January 2014 to April 2015 at the Programmatic Management of Drug-Resistant TB (PMDT) unit of Lady Reading Hospital (LRH) in Peshawar, Pakistan. Patient data were recorded in an Electronic Nominal Record System (ENRS). Statistical analysis was performed using SPSS software, with subjective data assessed through the Chi-Square test and quantitative data analyzed using Student's t-test. Both univariate and multivariate regression models were employed to explore the relationship between medication-related adverse reactions and treatment outcomes, setting a significance threshold at p < 0.05. Results: The study included 411 MDR-TB patients undergoing treatment. Of these, 360 patients were analyzed, comprising 212 (51.6%) males and 148 (36%) females, predominantly aged between 15-44 and 45-64 years. The most frequently reported side effects were psychiatric symptoms (67%), gastrointestinal issues (58.5%), ototoxicity (49.5%), and arthralgia/arthritis (48.7%). Psychiatric symptoms affected 241 (67%) patients, with 91 (25.3%) experiencing major adverse events. In contrast, 150 (41.6%) cases of adverse events were classified as non-serious and managed through additional medications or dosage adjustments. Conclusion: Adverse events are common among MDR-TB patients treated at PMDT-LRH Peshawar. Younger patients and those with cavitary lung disease should be monitored closely for the development of adverse events to enhance patient safety and treatment efficacy. [ABSTRACT FROM AUTHOR]

pncB1 and pncB2 are two putative nicotinic acid phosphoribosyltransferases, playing a role in cofactor salvage and drug resistance in Mycobacterium tuberculosis. Mutations have been reported in first- and second-line drug targets, causing resistance. However, pncB1 and pncB2 mutational data are not available, and neither of their mutation effects have been investigated in protein structures. The current study has been designed to investigate mutations and also their effects on pncB1 and pncB2 structures. A total of 287 whole-genome sequenced data of drug-resistant Mycobacterium tuberculosis isolates from Khyber Pakhtunkhwa of Pakistan were retrieved (BioSample PRJEB32684, ERR2510337-ERR2510445, ERR2510546-ERR2510645) from NCBI. The genomic data were analyzed for pncB1 and pncB2 mutations using PhyResSE. All the samples harbored numerous synonymous and non-synonymous mutations in pncB1 and pncB2 except one. Mutations Pro447Ser, Arg286Arg, Gly127Ser, and delTCAGGCCG1499213>1499220 in pncB1 are novel and have not been reported in literature and TB databases. The most common non-synonymous mutations exhibited stabilizing effects on the pncB1 structure. Moreover, 36 out of 287 samples harbored two non-synonymous and 34 synonymous mutations in pncB2 among which the most common was Phe204Phe (TTT/TTC), present in 8 samples, which may have an important effect on the usage of specific codons that may increase the gene expression level or protein folding effect. Mutations Ser120Leu and Pro447Ser, which are present in the loop region, exhibited a gain in flexibility in the surrounding residues while Gly429Ala and Gly127Ser also demonstrated stabilizing effects on the protein structure. Inhibitors designed based on the most common pncB1 and pncB2 mutants may be a more useful strategy in high-burden countries. More studies are needed to elucidate the effect of synonymous mutations on organism phenotype. [ABSTRACT FROM AUTHOR]

Background: Pyrazinamide (PZA) is an important component of first-line drugs because of its distinctive capability to kill subpopulations of persistent Mycobacterium tuberculosis (MTB). The prodrug (PZA) is converted to its active form, pyrazinoic acid (POA) by MTB pncA-encoded pyrazinamidase (PZase). Mutation in pncA is the most common and primary cause of PZA resistance. The aim of the present study was to explore the molecular characterization of PZA resistance in a Pashtun-dominated region of Khyber Pakhtunkhwa, Pakistan.Methods: We performed drug susceptibility testing (DST) on 753 culture-positive isolates collected from the Provincial Tuberculosis Control Program Khyber Pakhtunkhwa using the BACTEC MGIT 960 PZA method. In addition, the pncA gene was sequenced in PZA-resistant isolates, and PZA susceptibility testing results were used to determine the sensitivity and specificity of pncA gene mutations.Results: A total of 69 isolates were PZA resistant (14.8%). Mutations were investigated in 69 resistant, 26 susceptible and one H37Rv isolates by sequencing. Thirty-six different mutations were identified in PZA-resistant isolates, with fifteen mutations, including 194_203delCCTCGTCGTG and 317_318delTC, that have not been reported in TBDRM and GMTV Databases and previous studies. Mutations Lys96Thr and Ser179Gly were found in the maximum number of isolates (n = 4 each). We did not detect mutations in sensitive isolates, except for the synonymous mutation 195C > T (Ser65Ser). The sensitivity and specificity of the pncA sequencing method were 79.31% (95% CI, 69.29 to 87.25%) and 86.67% (95% CI, 69.28 to 96.24%).Conclusion: Mutations in the pncA gene in circulating isolates of geographically distinct regions, especially in high-burden countries, should be investigated for better control and management of drug-resistant TB. Molecular methods for the investigation of PZA resistance are better than DST. [ABSTRACT FROM AUTHOR]

Background: Tuberculosis is a chronic contagious disease whose compliance to treatment is low especially in children. Objectives: To diagnose tuberculosis in children using modified Pakistan Pediatric Association Scoring System and to determine their compliance to treatment. Study type, settings and duration: Descriptive study carried out in out-patient clinic of Pediatric Special Unit, Services Hospital/ Services Institute of Medical Sciences, Lahore from 1st December, 2004 till 30th June, 2006. Patients and Methods: All newly diagnosed children (3 months to 15 years) attending the Pediatric special outpatient clinic were scored according to Pakistan Pediatric Association Scoring Chart and those having a score of >7 or 5-6 with suggestive investigations were diagnosed to have tuberculosis. Diagnostic BCG (instead of Mauntoux Test) of more than 10mm was taken as positive. The family members were also screened for tuberculosis. Most children were treated with 3 drugs (Isoniazid, Rifampicin and Pyrazinamide) for initial 2-3 months followed by 2 drugs (Isoniazid and Rifampicin) for next 4 to 9 months. They were followed at 15 days intervals and all visits were recorded. Results: Out of 2645 children, 116(4.3%) had tuberculosis. Their mean age was 8.2 years ( 3.96) with 59 boys and 57 girls. Majority (n=110) had pulmonary tuberculosis and most responded well to 3 drugs initially (H,R,Z). Follow up was available in 103, out of whom 79(76.7%) completed 6 months treatment. Regular follow up was seen in 64(62.1%) patients. Conclusion: Though early detection for tuberculosis in children and family was done but their compliance to treatment was lower than the millennium goals (85%). [ABSTRACT FROM AUTHOR]

Aims: Pyrazinamide (PZA) is an important component of first-line tuberculosis (TB) treatment because of its distinctive capability to kill subpopulations of persister Mycobacterium tuberculosis (MTB). The significance of PZA can be understood by its inclusion in the most recent World Health Organization-recommended multidrug-resistant (MDR) TB regimen. Very little information is available about the prevalence of PZA-resistant TB from geographically distinct regions of high burden countries, including Khyber Pakhtunkhwa (KPK), Pakistan, because drug susceptibility testing (DST) of PZA is not regularly performed due to the complexity. In this study, we aimed to find the prevalence of PZA resistance in geographically distinct, Pashtun-dominant KPK Province of Pakistan and its correlation with other first- and second-line drug resistance., Materials and Methods: In this study, DST of PZA was performed through an automated BACTEC MGIT 960 system (BD Diagnostic Systems). The resistant samples were further subjected to DST of isoniazid (INH), rifampicin (RIF), ethambutol (EMB), streptomycin (SM), moxicillin (MOX), amikacin (AMK), ofloxacin (OFX), kanamycin (KM), and capreomycin (CAP)., Results: Out of 1,075 MTB-positive isolates, 83 (7.7%) were found to be resistant to PZA. Among the PZA-resistant isolates, 76 (90-91.6%) and 67 (80-80.7%) were found to be resistant to INH and RIF, respectively, whereas 63 (76%) were resistant to both first-line drugs, INH and RIF (MDR-TB). The resistance level of EMB, OFX, and SM was also significantly high in PZA resistance, 35 (42%), 40 (48%), and 41 (49-50%) respectively., Conclusion: PZA resistance is significantly associated with other first- and second-line drug resistance. A significant number of PZA-resistant isolates are MDR cases. Therefore, DST of PZA should regularly be performed along with other drugs for better management of treatment of MDR and extensively drug resistant (XDR), to avoid side effects in patients.

Prevalence of zoonotic Mycobacterium bovis (bTB) disease in human population is underreported from the North of Pakistan. Here, we report on the proportion of human bTB disease among the overall TB patients, drug resistance pattern of bTB isolates, and knowledge, attitude, and practices (KAP)-based analysis of bTB disease. For this purpose, sputum samples from a total of 300 clinically diagnosed TB patients and 100 randomly selected school children suspected of pulmonary TB were processed by culture as well as polymerase chain reaction (PCR) for isolation, identification, and confirmation of Mycobacterium tuberculosis (mTB) and bTB species. Isolates of bTB were processed for drug susceptibility tests. Data on KAP regarding TB were obtained on a pretested questionnaire. Sputum-based PCR results indicated that 288/300 (96%) were confirmed as mTB, while 12/300 (4%) were found as bTB diseases. Interestingly, none of the school child was declared positive for either mTB or bTB. Notably, 274/300 (91.3%) positively cultured samples were identified as mTB, 13/300 (4.3%) as bTB, while 5/300 (1.7%) as mixed containing both. Importantly, except one, all of the bTB isolates were found resistant to pyrazinamide. Surprisingly, most of the bTB isolates (~70%) were found resistant to a broad range of first- and second-line anti-TB drugs. SplitsTree and recombination analysis indicated no evidence of intergenic recombination. Finally, residence, occupation, presence of animals at home, and sleeping alongside animals were found significantly associated with occurrence of bTB disease. To the best of our knowledge, we report for the first time on the high (4%) burden of bTB disease in human TB patients in Peshawar, Pakistan.