A mixed methods evaluation of a differentiated care model piloted for TB care in south India.

Background: India's National TB Elimination Program emphasizes patient-centered care to improve TB treatment outcomes. We describe the lessons learned from the implementation of a differentiated care model for TB care among individuals diagnosed with active TB. Design and methods: Used mixed methods to pilot the Differentiated Care Model. Community health workers (CHWs) conducted a risk and needs assessment among individuals who were recently began TB treatment. Individuals identified with specific factors that are associated with poor treatment adherence were provided education, counseling, and linked to treatment and support services. Examined changes in TB treatment outcomes between the two cohorts of individuals on TB treatment before and after the intervention. We used qualitative research methods to explore the experiences of patients, family members, and front-line TB workers with the implementation of the DCM pilot. Results: The CHWs were adept at the identification of individuals with risks to non-adherence. However, only a few provided differentiated care, as envisioned. There was no significant change in the TB treatment outcomes between the two cohorts of patients examined. CHWs' ability to provide differentiated care on a scale was limited by the short duration of implementation, their inadequate skills to manage co-morbidities, and the suboptimal support at the field level. Conclusions: It is feasible for a cadre of well-trained front-line workers, mentored and supported by counselors and doctors, to provide differentiated care to those at risk for unfavorable TB treatment outcomes. However, differentiated care must be implemented on a scale for a duration that allows a change from the conventional practice of front-line workers, in order to influence the outcomes of population-level TB treatment.

Tuberculosis treatment outcomes and patient support groups, southern India.

Objective: To assess treatment outcomes in tuberculosis patients participating in support group meetings in five districts of Karnataka and Telangana states in southern India. Methods: Tuberculosis patients from five selected districts who began treatment in 2019 were offered regular monthly support group meetings, with a focus on patients in urban slum areas with risk factors for adverse outcomes. We tracked the patients' participation in these meetings and extracted treatment outcomes from the Nikshay national tuberculosis database for the same patients in 2021. We compared treatment outcomes based on attendance of the support groups meetings. Findings: Of 30 706 tuberculosis patients who started treatment in 2019, 3651 (11.9%) attended support groups meetings. Of patients who attended at least one support meeting, 94.1% (3426/3639) had successful treatment outcomes versus 88.2% (23 745/26 922) of patients who did not attend meetings (adjusted odds ratio, aOR: 2.44; 95% confidence interval, CI: 2.10-2.82). The odds of successful treatment outcomes were higher in meeting participants than non-participants for all variables examined including: age ≥ 60 years (aOR: 3.19; 95% CI: 2.26-4.51); female sex (aOR: 3.33; 95% CI: 2.46-4.50); diabetes comorbidity (aOR: 3.03; 95% CI: 1.91-4.81); human immunodeficiency virus infection (aOR: 3.73; 95% CI: 1.76-7.93); tuberculosis retreatment (aOR: 1.69; 1.22-2.33); and drug-resistant tuberculosis (aOR: 1.93; 95% CI: 1.21-3.09). Conclusion: Participation in support groups for tuberculosis patients was significantly associated with successful tuberculosis treatment outcomes, especially among high-risk groups. Expanding access to support groups could improve tuberculosis treatment outcomes at the population level.

Size-Dependent Antibacterial, Antidiabetic, and Toxicity of Silver Nanoparticles Synthesized Using Solvent Extraction of Rosa indica L. Petals.

In this study, silver nanoparticles (AgNPs) are synthesized through a green approach by employing Rosa indica L. petal (RE) extracts as reducing and stabilizing agents, which are extracted using three different solvents: ethanol (Et), acetone (Ac), and water (Aq). The phase formation of the AgNPs is confirmed using X-ray diffraction (XRD). Morphological analysis is performed using a field-emission scanning electron microscope (FESEM), which reveals that the AgNPs are spherical in shape. The size is estimated using ImageJ software, which is found to be ~12, 18, and 770 nm for RE-Ac-Ag, RE-Et-Ag, and RE-Aq-Ag, respectively. The phytochemicals of Rosa indica L. petals involved in the formation of the AgNPs are studied using Fourier transform infrared spectroscopy (FTIR). Finally, these materials are studied for their antibacterial, antidiabetic, antioxidant, and hemolytic activity, as well as cell toxicity properties. The materials, RE-Ac-Ag and RE-Et-Ag, are found to be more effective than RE-Aq-Ag in inhibiting E. coli (Gram-negative bacteria) and S. aureus (Gram-positive bacteria). Hemolytic studies reveal that all of the samples show concentration-dependent activity up to 50 µg/mL. RE-Ac-Ag and RE-Et-Ag exhibit nonhemolytic behavior, whereas RE-Aq-Ag remains nonhemolytic until 100 µg/mL. The antidiabetic ability of the AgNPs is evaluated using α-amylase inhibition assay (DNSA assay) and α-glucosidase inhibition assay. The results are found to be effective, with IC50 values of α-amylase and α-glycosidase being 50, 50, and 75 µg/mL for RE-Et-Ag, RE-Ac-Ag, and RE-Aq-Ag, respectively. DPPH assay shows that the AgNPs inhibited the antioxidants well, with IC50 values of 40 µg/mL for RE-Et-Ag and RE-Ac-Ag and 60 µg/mL for RE-Aq-Ag. The toxicity study reveals that the AgNPs show size- and concentration-dependent behavior. Overall, it is realized from the findings that RE-Ac-Ag, RE-Et-Ag, and RE-Aq-Ag show size-dependent antibacterial, antidiabetic, and toxicity properties.

Community health workers augment the cascade of TB detection to care in urban slums of two metro cities in India.

BACKGROUND: Tuberculosis Health Action Learning Initiative (THALI) funded by USAID is a person-centered initiative, supporting vulnerable urban populations to gain access to TB services. THALI trained and placed 112 Community health workers (CHWs) to detect and support individuals with TB symptoms or disease within urban slums in two cities, Hyderabad and Bengaluru, covering a population of about 3 million. METHODS: CHWs visited the slums once in a fortnight. They conducted TB awareness activities. They referred individuals with TB symptoms for sputum testing to nearest public sector laboratories. They visited those testing TB positive, once a fortnight in the intensive phase, and once a month thereafter. They supported TB patients and families with counselling, contact screening and social scheme linkages. They complemented the shortfall in urban TB government field staff numbers and their capacity to engage with TB patients. Data on CHWs' patient referral for TB diagnosis and treatment support activities was entered into a database and analyzed to examine CHWs' role in the cascade of TB care. We compared achievements of six monthly referral cohorts from September 2016 to February 2019. RESULTS: Overall, 31 617 (approximately 1%) of slum population were identified as TB symptomatic and referred for diagnosis. Among the referred persons, 23 976 (76%) underwent testing of which 3841 (16%) were TB positive. Overall, 3812 (99%) were initiated on treatment and 2760 (72%) agreed for regular follow up by the CHWs. Fifty-seven percent of 2952 referred were tested in the first cohort, against 86% of 8315 in the last cohort. The annualized case detection rate through CHW referrals in Bengaluru increased from 5.5 to 52.0 per 100 000 during the period, while in Hyderabad it was 35.4 initially and increased up to 118.9 per 100 000 persons. The treatment success rate was 87.1% among 193 in the first cohort vs 91.3% among 677 in the last cohort. CONCLUSIONS: CHWs in urban slums augment TB detection to care cascade. Their performance and TB treatment outcomes improve over time. It would be important to examine the cost per TB case detected and successfully treated.

Characterization of plasmids in extensively drug-resistant acinetobacter strains isolated in India and Pakistan.

The blaNDM-1 gene is associated with extensive drug resistance in Gram-negative bacteria. This probably spread to Enterobacteriaceae from Acinetobacter spp., and we characterized plasmids associated with blaNDM-1 in Acinetobacter spp. to gain insight into their role in this dissemination. Four clinical NDM-1-producing Acinetobacter species strains from India and Pakistan were investigated. A plasmid harboring blaNDM-1, pNDM-40-1, was characterized by whole-genome sequencing of Acinetobacter bereziniae CHI-40-1 and comparison with related plasmids. The presence of similar plasmids in strains from Pakistan was sought by PCR and sequencing of amplicons. Conjugation frequency was tested and stability of pNDM-40-1 investigated by real-time PCR of isolates passaged with and without antimicrobial selection pressure. A. bereziniae and Acinetobacter haemolyticus strains contained plasmids similar to the pNDM-BJ01-like plasmids identified in Acinetobacter spp. in China. The backbone of pNDM-40-1 was almost identical to that of pNDM-BJ01-like plasmids, but the transposon harboring blaNDM-1, Tn125, contained two short deletions. Escherichia coli and Acinetobacter pittii transconjugants were readily obtained. Transconjugants retained pNDM-40-1 after a 14-day passage experiment, although stability was greater with meropenem selection. Fragments of pNDM-BJ01-like plasmid backbones are found near blaNDM-1 in some genetic contexts from Enterobacteriaceae, suggesting that cross-genus transfer has occurred. pNDM-BJ01-like plasmids have been described in isolates originating from a wide geographical region in southern Asia. In vitro data on plasmid transfer and stability suggest that these plasmids could have contributed to the spread of blaNDM-1 into Enterobacteriaceae.

Plasmid carriage of bla NDM-1 in clinical Acinetobacter baumannii isolates from India.

NDM-1 probably emerged in Acinetobacter species prior to its dissemination among Enterobacteriaceae, and NDM-1-like enzymes are increasingly reported in Acinetobacter species. Here, we report on the genetic context of blaNDM-1 in the earliest known NDM-1-producing organisms, clinical isolates of Acinetobacter from India in 2005. These strains harbor blaNDM-1 plasmids of different sizes. The gene is associated with the remnants of the Tn125 transposon normally associated with blaNDM-1 in Acinetobacter spp. The transposon has been disrupted by the IS26 insertion and subsequent movement events.

Clinical epidemiology of the global expansion of Klebsiella pneumoniae carbapenemases.

Klebsiella pneumoniae carbapenemases (KPCs) were originally identified in the USA in 1996. Since then, these versatile ß-lactamases have spread internationally among Gram-negative bacteria, especially K pneumoniae, although their precise epidemiology is diverse across countries and regions. The mortality described among patients infected with organisms positive for KPC is high, perhaps as a result of the limited antibiotic options remaining (often colistin, tigecycline, or aminoglycosides). Triple drug combinations using colistin, tigecycline, and imipenem have recently been associated with improved survival among patients with bacteraemia. In this Review, we summarise the epidemiology of KPCs across continents, and discuss issues around detection, present antibiotic options and those in development, treatment outcome and mortality, and infection control. In view of the limitations of present treatments and the paucity of new drugs in the pipeline, infection control must be our primary defence for now.

AmpC ß-lactamases in nosocomial isolates of Klebsiella pneumoniae from India.

BACKGROUND & OBJECTIVES: AmpC ß-lactamases are clinically significant since these confer resistance to cephalosporins in the oxyimino group, 7-α methoxycephalosporins and are not affected by available ß-lactamase inhibitors. In this study we looked for both extended spectrum ß-lactamases (ESBL) and AmpC ß-lactamases in Klebsiella pneumoniae clinical isolates. METHODS: One hundred consecutive, non-duplicate clinical isolates of K. pneumoniae collected over a period of one year (June 2008 - June 2009) were included in the study. An antibiotic susceptibility method was used with 10 antibiotics for Gram-negative infections which helped in screening for ESBL and AmpC ß-lactamases and also in confirmation of ESBL production. The detection of AmpC ß-lactamases was done based on screening and confirmatory tests. For screening, disc diffusion zones of cefoxitin <18 mm was taken as cefoxitin resistant. All cefoxitin resistant isolates were tested further by AmpC disk test and modified three dimensional test. Multiplex-PCR was performed for screening the presence of plasmid-mediated AmpC genes. RESULTS: Of the 100 isolates of K. pneumoniae studied, 48 were resistant to cefoxitin on screening. AmpC disk test was positive in 32 (32%) isolates. This was also confirmed with modified three dimensional test. Indentation indicating strong AmpC producer was observed in 25 isolates whereas little distortion (weak AmpC) was observed in 7 isolates. ESBL detection was confirmed by a modification of double disk synergy test in 56 isolates. Cefepime was the best cephalosporin in synergy with tazobactam for detecting ESBL production in isolates co-producing AmpC ß-lactamases. The subsets of isolates phenotypically AmpC ß-lactamase positive were subjected to amplification of six different families of AmpC gene using multiplex PCR. The sequence analysis revealed 12 CMY-2 and eight DHA-1 types. INTERPRETATION & CONCLUSIONS: Tazobactam was the best ß-lactamase inhibitor for detecting ESBL in presence of AmpC ß-lactamase as this is a very poor inducer of AmpC gene. Amongst cephalosporins, cefepime was the best cephalosporin in detecting ESBL in presence of AmpC ß-lactamase as it is least hydrolyzed by AmpC enzymes. Cefepime-tazobactam combination disk test would be a simple and best method in detection of ESBLs in Enterobacteriaceae co-producing AmpC ß-lactamase in the routine diagnostic microbiology laboratories.

Emergence of a new antibiotic resistance mechanism in India, Pakistan, and the UK: a molecular, biological, and epidemiological study.

BACKGROUND: Gram-negative Enterobacteriaceae with resistance to carbapenem conferred by New Delhi metallo-beta-lactamase 1 (NDM-1) are potentially a major global health problem. We investigated the prevalence of NDM-1, in multidrug-resistant Enterobacteriaceae in India, Pakistan, and the UK. METHODS: Enterobacteriaceae isolates were studied from two major centres in India--Chennai (south India), Haryana (north India)--and those referred to the UK's national reference laboratory. Antibiotic susceptibilities were assessed, and the presence of the carbapenem resistance gene bla(NDM-1) was established by PCR. Isolates were typed by pulsed-field gel electrophoresis of XbaI-restricted genomic DNA. Plasmids were analysed by S1 nuclease digestion and PCR typing. Case data for UK patients were reviewed for evidence of travel and recent admission to hospitals in India or Pakistan. FINDINGS: We identified 44 isolates with NDM-1 in Chennai, 26 in Haryana, 37 in the UK, and 73 in other sites in India and Pakistan. NDM-1 was mostly found among Escherichia coli (36) and Klebsiella pneumoniae (111), which were highly resistant to all antibiotics except to tigecycline and colistin. K pneumoniae isolates from Haryana were clonal but NDM-1 producers from the UK and Chennai were clonally diverse. Most isolates carried the NDM-1 gene on plasmids: those from UK and Chennai were readily transferable whereas those from Haryana were not conjugative. Many of the UK NDM-1 positive patients had travelled to India or Pakistan within the past year, or had links with these countries. INTERPRETATION: The potential of NDM-1 to be a worldwide public health problem is great, and co-ordinated international surveillance is needed.