Retrospective Analysis of Hospital Acquired Infection and Antibiotic Resistance in Coronary Care Unit (CCU), Adult, and Pediatric Cardiology Wards.

BACKGROUND: Antibiotics resistance is an paramount threat affecting the whole world but nowhere situation is as gloomy as in India. No study till date regarding epidemiology of hospital acquired infections in coronary care units(CCU) and cardiology wards from India. From Indian perspective it is the first observational study to analyse microbiological profile and antibiotic resistance in CCU. The purpose of this observational study is to explore the epidemiology and importance of infections in CCU patients. METHODOLOGY: After ethics committee approval, the records of all patients who were admitted in coronary care units, adult and pediatric cardiology wards surgery between January 2020 and December 2021 were reviewed retrospectively. The type of organism,source of infection ,age wise distribution and seasonal variability among patients who developed hospital acquired infection (HAI) were determined. RESULTS: 271 patients developed microbiologically documented HAI during from January 2020 to December 2021. Maximum number of organisms(78/271 28.78%) are isolated from urinary samples ,followed by blood stream(60/271 22.14%) and Endotracheal tube (54/271 19.92%). Acinetobacter baumanii (53/271, 19.5%) being the most common isolate among all the samples taken . Acinetobacter was the most frequent pathogens isolated in patients with LRTI and blood stream infection while E. coli was from urinary tract infection . In the adult population, infection with E. coli(24.6%) is the most common followed by Klebsiella pneumoniae (12.8%) and Acinetobacter baumanii (10.1%). In the pediatric population Acinetobacter baumanii (38.6%%) is the most common followed by Klebsiella pneumoniae (20.5%) and Methicillin Resistant Staphylococcus aureus, MRSA (6.8%). Commonly used antibiotics eg ciprofloxacin,ceftazidime and amikacin were found to be resistant against the top three isolates. CONCLUSION: Urinary tract was the most common site of infection and Gram-negative bacilli, the most common pathogens in adult as well as pediatric population. Antibiotic resistance was maximum with commonly isolated microorganisms.

Antimicrobial efficacy of eravacycline against emerging extensively drug-resistant (XDR) Acinetobacter baumannii isolates.

PURPOSE: Drug-resistant Acinetobacter baumannii is an emerging threat. This study has been conducted to observe the efficacy of eravacycline along with the RND-efflux pump system. METHODS: A cross-sectional study was done collecting 48 clinical isolates of Acinetobacter baumannii. MICs of 15 antibiotics were detected along with BMD of tigecycline and eravacycline. PCR products of drug-resistant regulatory genes were sequenced and analyzed. RESULTS: Of the total 48 Isolates, 35 (72.91%) were XDR and 13 (27.08%) were MDR. Out of all, 60.41% of isolates were found to be susceptible to eravacycline by BMD according to both FDA and EUCAST guidelines. A 2-fold decline of MIC50/90 was observed with the use of eravacycline compared to tigecycline. RND-efflux genes like AdeC in 30 (62.5%) isolates and Regulatory gene AdeS in 29 (60.41%) isolates were detected, explaining the existing resistance mechanism. CONCLUSIONS: XDR Acinetobacter poses an escalating threat due to its resistance to multiple antibiotics, raising serious concerns in healthcare settings. Eravacycline is an encouraging new drug for empirical use in severe infection caused due to the same. Molecular investigation and strict antimicrobial stewardship should be followed to control the emergence, and a better understanding of mechanisms of resistance to prevent the spread of drug-resistant isolates.

Safety of Procalcitonin Guided Early Discontinuation of Antibiotic Therapy among Children Receiving Cancer Chemotherapy and Having Low-Risk Febrile Neutropenia: A Randomized Feasibility Trial (ProFenC Study).

In low-risk febrile neutropenia (LR-FN), the safety of early discontinuation of empiric antibiotics without marrow recovery is not well established. This study aimed to evaluate the safety of procalcitonin (PCT) guided early discontinuation of antibiotics in LR-FN. In this trial, children with LR-FN with an afebrile period of at least 24 h, sterile blood culture, and negative/normalized PCT were randomized at 72 h of starting antibiotics into two groups: intervention arm and standard arm. The antibiotics were stopped in the intervention arm regardless of absolute neutrophil count (ANC), while in the standard arm, antibiotics were continued for at least 7 days or until recovery of ANC (>500/mm3). The primary objective was to determine the treatment failure rates, and the secondary objective was to compare the duration of antibiotics and all-cause mortality between the two arms. A total of 46 children with LR-FN were randomized to either the intervention arm (n = 23) or the standard arm (n = 23). Treatment failure was observed in 2/23 (8.7%) of patients in the intervention arm compared to 1/23 (4.3%) in the standard arm [RR: 2 (95% CI: 0.19-20.6); p = 0.55]. The median duration of antibiotics in the intervention arm and standard arm were 3 days vs 7 days (P= <0.001). There was no mortality in this study. PCT-guided early discontinuation of empirical antibiotics in LR-FN is feasible. There was no significant difference observed in treatment failure between the early discontinuation of antibiotics vs standard therapy. The total duration of antibiotic exposure was significantly lesser in the discontinuation arm. Further, larger multicenter studies are needed to confirm the finding of this study.

Detection of Aminoglycoside Modifying Enzyme (AME) genes in Acinetobacter baumannii isolates and the inhibitory effect of efflux pump activity on drug susceptibility pattern.

INTRODUCTION: The development of aminoglycoside modifying enzymes (AMEs) and increased efflux activity are considered important aminoglycosides resistance mechanisms. AIM: This study is focused on the detection of the AMEs gene and assessing the effect of efflux pump inhibitor on the reversal of A. baumannii drug susceptibility. METHODOLOGY: Bacterial DNA was amplified using AMEs gene-specific primers. Isolates were also investigated for efflux pump activity using efflux pump inhibitor (EPI) i.e. Carbonyl cyanide m-chlorophenyl hydrazone (CCCP) and the impact of both mechanisms was analyzed. RESULTS: Among A. baumannii isolates, 55% isolates (n â€‹= â€‹22/40) were identified to have aminoglycoside modifying enzymes genes; ant(3')-I gene (50%, 11/22), aac(6')-Ib gene (45.4%, 10/22), aph(3')-I gene (18.1%, 4/22) and aac(3)-I (9.1%, 2/22). Total 70% isolates have shown MIC alteration in different classes of drugs in response to EPI-CCCP. Such alteration was found in 100% amikacin sensitive and 58.6% amikacin resistant, 93.7% and 57.1% gentamicin sensitive and resistant isolates respectively. CONCLUSION: The presence of aminoglycosides modifying enzymes was frequent among aminoglycosides resistant A. baumannii isolates and the coexistence of efflux pumps activity also plays an important role to increase drug resistance. REPOSITORIES: Genbank and their accession numbers are MT903331[aac(3)-I], MT903332 MT903333 [ant(3')-I], MT903334, MT903335 [aph(3')-I)] and MT903336, MT940242 [ aac(6')-Ib].

Ceftriaxone-resistant Salmonella Typhi isolated from paediatric patients in north India: Insights into genetic profiles and antibiotic resistance mechanisms.

PURPOSE: To investigate the antibiotic resistance and genetic profile of ceftriaxone-resistant Salmonella Typhi isolated from the blood culture of two paediatric cases of typhoid fever and one from the stool culture of their household contact, in North India. METHODS: In this study, whole-genome sequencing was carried out with paired-end 2 â€‹× â€‹150 bp reads on Illumina MiSeq (Illumina, USA) employing v2 and v3 chemistry. To check data quality, adapters and low-quality sequences were removed through Trimmomatic-v0.36. High quality reads were then assembled de novo using A5-miseq pipeline. For further refinement, reference-guided contig ordering and orienting were performed on the scaffold assemblies using ABACAS (http://abacas.sourceforge.net/). The assembled genome was annotated using Prokka v1.12 to identify and annotate the gene content. Plasmid replicons in bacterial isolates were identified by PlasmidFinder, whereas mobile genetic elements were predicted using Mobile Element Finder. Referenced-based SNP tree with maximum likelihood method was built with CSI phylogeny v1.4. RESULTS: All three isolates exhibited resistance to ceftriaxone, cefixime, ciprofloxacin, ampicillin, and co-trimoxazole, while demonstrating sensitivity to azithromycin and chloramphenicol. The whole-genome sequencing of these strains revealed the presence of blaCTX-M-15 gene for cephalosporin resistance in addition to gyrA, qnr and IncY plasmid replicon. A 5 â€‹kb IS91 Sbo1 gene cassette (IncY plasmid) was identified which carried extended spectrum ß-lactamase blaCTX-M-15, blaTEM-1D (resistance to ampicillin and cephalosporin), sul2, dfrA14 (resistant to trimethoprim-sulfamethoxazole) and qnrS (resistant to ciprofloxacin). These isolates belong to H58 lineage and grouped as sequence type 1 (ST1) on multilocus sequence typing (MLST) analysis. CONCLUSION: In the present study we report the isolation of blaCTX-M-15 positive S. Typhi from two paediatric patients presenting with fever and one from stool culture of their contact from North India and highlight the need for further investigations to understand the different factors contributing to ceftriaxone resistance in Salmonella Typhi.

Central Line-Associated Bloodstream Infections: Effect of Patient and Pathogen Factors on Outcome.

Introduction: Patients on central lines are often having multiple morbidities, and invasive devices provide a niche for biofilm formation, which makes central line-associated bloodstream infections (CLABSIs), a serious concern in health-care settings, as the infections difficult to treat. In this study, we evaluated the common bacteria causing CLABSI, and various patient and pathogen factors affecting the clinical outcome. Methods: In the prospective observational study, patients diagnosed with CLABSI were recruited. Extensive clinical, microbiological, and other laboratory workup was done, and observations were recorded. Congo red agar method, tube test, and microtiter plate assay were used for eliciting the biofilm-forming attributes of the bacterial pathogens. Results: Klebsiella pneumoniae was responsible for 48% of CLABSI, followed by Coagulase-negative Staphylococci (16%) and Staphylococcus aureus and Acinetobacter baumannii (12% each). Fifty-six percent of the isolates produced biofilms. The median (interquartile range) duration of hospital stay till death or discharge was 30 (20, 43) days. The all-cause mortality was 44%. Patients having a deranged liver function on the day of diagnosis (P value for total bilirubin 0.001 and for aspartate transaminase 0.02), and those infected with multidrug-resistant organisms (P value = 0.04) had significantly poor prognosis. The difference in the demographic, clinical, laboratory profile, and outcome of patients infected with biofilm producers and nonproducers was not found to be statistically significant. Conclusion: The study throws light on various host and pathogen factors determining the cause and outcome of CLABSI patients. To the best of our knowledge, this is the first study trying to decipher the role of biofilm formation in the virulence of pathogens and the prognosis of CLABSI.

Procalcitonin for Detecting Culture-Positive Sepsis in Neonates: A Prospective, Multicenter Study.

INTRODUCTION: It is unclear if serum procalcitonin (PCT) estimated at sepsis suspicion can help detect culture-positive sepsis in neonates. We evaluated the diagnostic performance of PCT in culture-positive sepsis in neonates. METHODS: This was a prospective study (February 2016 to September 2020) conducted in four level-3 units in India. We enrolled neonates suspected of sepsis in the first 28 days of life. Neonates with birth weight <750 g, asphyxia, shock, and major malformations were excluded. Blood for PCT assay was drawn along with the blood culture at the time of suspicion of sepsis and before antibiotic initiation. The investigators labeled the neonates as having culture-positive sepsis or "no sepsis" based on the culture reports and clinical course. PCT assay was performed by electrochemiluminescence immunoassay, and the clinicians were masked to the PCT levels while assigning the label of sepsis. Primary outcomes were the sensitivity, specificity, and likelihood ratios to identify culture-positive sepsis. RESULTS: The mean birth weight (SD) and median gestation (IQR) were 2,113 (727) g and 36 (32-38) weeks, respectively. Of the 1,204 neonates with eligible cultures, 155 (12.9%) had culture-positive sepsis. Most (79.4%) were culture-positive within 72 h of birth. The sensitivity, specificity, and positive and negative likelihood ratios at 2 ng/mL PCT threshold were 52.3% (95% confidence interval: 44.1-60.3), 64.5% (60.7-68.1), 1.47 (1.23-1.76), and 0.74 (0.62-0.88), respectively. Adding PCT to assessing neonates with 12.9% pretest probability of sepsis generated posttest probabilities of 18% and 10% for positive and negative test results, respectively. CONCLUSION: Serum PCT did not reliably identify culture-positive sepsis in neonates.

Tick-tock, beat the clock: comparative analysis of disc diffusion testing with 6-, 10-, and 24-h growth for accelerated antimicrobial susceptibility testing and antimicrobial stewardship.

Disc diffusion testing by Kirby-Bauer technique is the most used method for determining antimicrobial susceptibility in microbiological laboratories. The current guidelines by The Clinical and Laboratory Standards Institute (CLSI) 2022 specify using an 18- to 24-h growth for testing by disc diffusion. We aim to determine if using an early growth (6 h and 10 h) would produce comparable results, thus ultimately leading to reduced turnaround time. Six-hour, 10-h, and 24-h growths of 20 quality control strains and 6-h and 24-h growths of 48 clinical samples were used to perform disc diffusion testing using a panel of appropriate antimicrobial agents. Disc diffusion zone sizes were interpreted for all and comparative analyses were performed to determine categorical agreement, minor errors (mE), major errors (ME), and very major errors (VME) according to CLSI guidelines. On comparing with the standard 24 h of incubation, disc diffusion from 6-h and 10-h growths of quality control strains showed 94.38% categorical agreement, 5.10% mE, 0.69% MEs, and no VMEs. Disc diffusion testing for the additional 40 clinical samples yielded a similarly high level of categorical agreement (98.15%) and mE, ME, and VME of 1.29%, 1.22%, and 0% respectively. Disc diffusion testing using early growth is a simple and accurate method for susceptibility testing that can reduce turnaround time and may prove to be critical for timely patient management.

Genomic analysis unveils genome degradation events and gene flux in the emergence and persistence of S. Paratyphi A lineages.

Paratyphoid fever caused by S. Paratyphi A is endemic in parts of South Asia and Southeast Asia. The proportion of enteric fever cases caused by S. Paratyphi A has substantially increased, yet only limited data is available on the population structure and genetic diversity of this serovar. We examined the phylogenetic distribution and evolutionary trajectory of S. Paratyphi A isolates collected as part of the Indian enteric fever surveillance study "Surveillance of Enteric Fever in India (SEFI)." In the study period (2017-2020), S. Paratyphi A comprised 17.6% (441/2503) of total enteric fever cases in India, with the isolates highly susceptible to all the major antibiotics used for treatment except fluoroquinolones. Phylogenetic analysis clustered the global S. Paratyphi A collection into seven lineages (A-G), and the present study isolates were distributed in lineages A, C and F. Our analysis highlights that the genome degradation events and gene acquisitions or losses are key molecular events in the evolution of new S. Paratyphi A lineages/sub-lineages. A total of 10 hypothetically disrupted coding sequences (HDCS) or pseudogenes-forming mutations possibly associated with the emergence of lineages were identified. The pan-genome analysis identified the insertion of P2/PSP3 phage and acquisition of IncX1 plasmid during the selection in 2.3.2/2.3.3 and 1.2.2 genotypes, respectively. We have identified six characteristic missense mutations associated with lipopolysaccharide (LPS) biosynthesis genes of S. Paratyphi A, however, these mutations confer only a low structural impact and possibly have minimal impact on vaccine effectiveness. Since S. Paratyphi A is human-restricted, high levels of genetic drift are not expected unless these bacteria transmit to naive hosts. However, public-health investigation and monitoring by means of genomic surveillance would be constantly needed to avoid S. Paratyphi A serovar becoming a public health threat similar to the S. Typhi of today.

Genome profiling of uropathogenic E. coli from strictly defined community-acquired UTI in paediatric patients: a multicentric study.

BACKGROUND: Urinary tract infection (UTI) in children is a common bacterial infection. The emergence of extended-spectrum beta-lactamases (ESBLs) poses a major challenge against the treatment of uropathogens. We aimed to characterize the E. coli isolates recovered from children with UTI for their resistance profile and circulating sequence types (ST). METHODS: Children (> 1.5-18 years of age) from different community health centres of India with symptoms of UTI were enrolled. Isolates causing significant bacteriuria were identified by Matrix-Assisted Laser Desorption Ionization Time of Flight Mass Spectrometry (MALDI-TOF MS) and tested for antimicrobial susceptibility by the automated system, VITEK-2 (Biomeriux, Durhum, US). Nineteen E. coli isolates (15 ESBL positive and 4 ESBL negative) were sequenced in Oxford Nanopore platform followed by core-genome phylogeny, accessory genome cluster analysis, identification of sequence types, mobile genetic elements, genetic antimicrobial resistance markers. The correlation between detection of antimicrobial resistance genes with phenotypic resistance profiles was also investigated. RESULTS: Eleven percent of children had significant bacteriuria [male:female-1:1, > 50% were 11-18 years of age group]. E. coli was predominant (86%) followed by K. pneumoniae (11%). Susceptibility of E. coli was highest against fosfomycin (100%) followed by carbapenems (90.7%) and nitrofurantoin (88.8%). ST131 (15.8%) and ST167 (10.5%) found as high-risk clones with the presence of plasmid [IncFIB (63.1%), IncFIA (52.6%)], and composite transposon [Tn2680 (46.6%)] in many isolates. Few isolates coharboured multiple beta-lactamases including blaNDM-5 (33.3%), blaOXA-1 (53.3%), blaCTX-M-15 (60%) and blaTEM-4 (60%). CONCLUSIONS: This study highlights horizontal transmission of resistance genes and plasmids in paediatric patients at community centers across the nation harbouring multidrug-resistant genes such as blaNDM-5 and blaCTX-M-15 associated with high-risk clones ST131 and ST167. The data is alarming and emphasizes the need for rapid identification of resistance markers to reduce the spread in community. To our knowledge, this is the first multicentric study targeting paediatric UTI patients from the community setting of India.

Computational biology: Role and scope in taming antimicrobial resistance.

BACKGROUND: Infectious diseases pose many challenges due to increasing threat of antimicrobial resistance, which necessitates continuous research to develop novel strategies for development of new molecules with antibacterial activity. In the era of computational biology there are tools and techniques available to address and solve the disease management issues in the field of clinical microbiology. The sequencing techniques, structural biology and machine learning can be implemented collectively to tackle infectious diseases e.g. for the diagnosis, epidemiological typing, pathotyping, antimicrobial resistance detection as well as the discovery of novel drugs and vaccine biomarkers. OBJECTIVES: The present review is a narrative review representing a comprehensive literature-based assessment regarding the use of whole genome sequencing, structural biology and machine learning for the diagnosis, molecular typing and antibacterial drug discovery. CONTENT: Here, we seek to present an overview of molecular and structural basis of resistance to antibiotics, while focusing on the recent bioinformatics approaches in whole genome sequencing and structural biology. The application of next generation sequencing in management of bacterial infections focusing on investigation of microbial population diversity, genotypic resistance testing and scope for the identification of targets for novel drug and vaccine candidates, has been addressed along with the use of structural biophysics and artificial intelligence.

Small molecule bio-signature in childhood intra-thoracic tuberculosis identified by metabolomics.

The diagnosis of pediatric tuberculosis (TB) remains a major challenge, hence the evaluation of new tools for improved diagnostics is urgently required. We investigated the serum metabolic profile of children with culture-confirmed intra-thoracic TB (ITTB) (n = 23) and compared it with those of non-TB controls (NTCs) (n = 13) using proton NMR spectroscopy-based targeted and untargeted metabolomics approaches. In targeted metabolic profiling, five metabolites (histidine, glycerophosphocholine, creatine/phosphocreatine, acetate, and choline) differentiated TB children from NTCs. Additionally, seven discriminatory metabolites (N-α-acetyl-lysine, polyunsaturated fatty acids, phenylalanine, lysine, lipids, glutamate + glutamine, and dimethylglycine) were identified in untargeted metabolic profiling. The pathway analysis revealed alterations in six metabolic pathways. The altered metabolites were associated with impaired protein synthesis, hindered anti-inflammatory and cytoprotective mechanisms, abnormalities in energy generation processes and membrane metabolism, and deregulated fatty acid and lipid metabolisms in children with ITTB. The diagnostic significance of the classification models obtained from significantly distinguishing metabolites showed sensitivity, specificity, and area under the curve of 78.2%, 84.6%, and 0.86, respectively, in the targeted profiling and 92.3%, 100%, and 0.99, respectively, in the untargeted profiling. Our findings highlight detectable metabolic changes in childhood ITTB; however, further validation is warranted in a large cohort of the pediatric population.

Genomic analysis of Fosfomycin resistance in multi-drug resistant uropathogens and comparison of in-vitro susceptibility methods uropathogens.

Background and Objectives: Urinary tract infection is one of the most common bacterial infections causing high morbidity and mortality. The alarming rise of multidrug-resistant uropathogens worldwide forced the clinician to rethink the old drugs like Fosfomycin for its therapeutic management. Our objective was to compare agar dilution, disc diffusion and E-test method for antimicrobial susceptibility testing of Fosfomycin against different drug-resistant uropathogens. Materials and Methods: Consecutive 181 uropathogens were tested for Fosfomycin susceptibility using agar dilution, disc diffusion and E-test. Results were interpreted using Clinical and Laboratory Standards Institute (CLSI) and European Committee on Antimicrobial Susceptibility Testing (EUCAST) breakpoints. Whole genome sequencing analysis was done on the 4 XDR/PDR Fosfomycin resistant Klebsiella pneumoniae isolates. Results: Escherichia coli was found as the most common (62.4%) uropathogen followed by Klebsiella pneumoniae (21%). Considering agar dilution as the gold standard, 6.1% of isolates were resistant to Fosfomycin. Following CLSI breakpoints, the susceptibility of Escherichia coli, Klebsiella pneumoniae, other Enterobacterales and Pseudomonas aeruginosa were 92.9%, 92.1%, 100%, 100%; whereas using EUCAST breakpoints the susceptibility rates were 85.7%, 86.9%, 92.9%, and 100%, respectively. The essential agreement, categorical agreement, major error, and very major error for E-test/disc diffusion for all the organisms were 91.2%/Not Applicable, 95%/93.9%, 1.8%/4.7%, 9.1%/9.1%, respectively. Whole-genome sequencing showed mutation UhpT gene as well as the presence of plasmid-mediated fosA5 or fosA6 genes conferring Fosfomycin resistance. Conclusion: This result supports very low resistance of Enterobacterales against Fosfomycin; hence should be considered a valuable option to treat multidrug-resistant uropathogens. Disc diffusion was observed to be a convenient method for Fosfomycin susceptibility testing compared to agar dilution.

Antibiotic resistance of uropathogens among the community-dwelling pregnant and nonpregnant female: a step towards antibiotic stewardship.

BACKGROUND: Indiscriminate and widespread use of antibiotics has resulted in emergence of many antibiotic-resistant organisms. Antibiotic administration during pregnancy is mostly avoided, unless there is compelling medical condition. We hypothesized that the uropathogens isolated from pregnant women would be more susceptible to antibiotics compared to those isolated from nonpregnant women, thus will be helpful in formulating separate empiric guideline for pregnant women based on the resistance pattern. METHODS: This was a prospective cross-sectional study conducted over a period of 2 years in which females with the clinical diagnosis of either cystitis or asymptomatic bacteriuria during pregnancy were included from the community settings. Uropathogen species and their antimicrobial resistance pattern were compared between the pregnant and nonpregnant groups. After accounting for centre-to-centre variation and adjusting for age and socio-economic status, the adjusted odds ratio for antibiotic resistance was calculated and compared between pregnant and nonpregnant women using logistic regression analysis. RESULTS: A total of 1758 women (pregnant: 43.3%; nonpregnant: 56.6%) were screened in the study over a period of 2 years, out of which 9.3% (163/1758) were having significant bacteriuria. Escherichia coli and Klebsiella pneumoniae were the two commonest uropathogen in both the groups; their prevalence being 83.6% in pregnant women and 85.2% in nonpregnant women, respectively. Resistance against ampicillin, cefixime, cefoxitin, ceftazidime, ceftriaxone and amoxicillin-clavulanic acid were found significantly lower in the pregnant women compared to nonpregnant. After adjusting the age and socio-economic status accounting for centre-to-centre variation, the odds of resistance for cefixime, amoxicillin-clavulanic acid and co-trimoxazole were found lower and statistically significant among the pregnant women group. CONCLUSIONS: The antimicrobial resistance was significantly higher among the community-dwelling nonpregnant women compared to pregnant women in case of few antibiotics. The study highlighted the need of building local antibiogram that could help to initiate the empirical treatment and thus prevent emergence of antimicrobial resistance.

Screening of plant-based natural compounds as an inhibitor of FtsZ from Salmonella Typhi using the computational, biochemical and in vitro cell-based studies.

Salmonella Typhi is emerging as a drug-resistant pathogen, particularly in developing countries. Hence, the progressive development of new antibiotics against novel drug targets is essential to prevent the spread of infections and mortality. The cell division protein FtsZ is an ideal drug target as the cell wall synthesis in bacteria is driven by the dynamic treadmilling nature of the FtsZ. The polymerization of the FtsZ provides the essential mechanical constricting force and flexibility to modulate the cell wall synthesis. Any alteration in FtsZ polymerization leads to the bactericidal or bacteriostatic effect. In this study, we have evaluated the secondary metabolites of natural compounds berberine chloride, cinnamaldehyde, scopoletin, quercetin and eugenol as potential inhibitors of FtsZ from Salmonella Typhi (stFtsZ) using computational, biochemical, and in vivo cell-based assays. Out of these five compounds, berberine chloride and cinnamaldehyde exhibited the best binding affinity of Kd = 7 µM and 10 µM, respectively and inhibit stFtsZ GTPase activity and polymerization by 70 %. The compound berberine chloride showed the best MIC of 500 µg/mL and 175 µg/mL against gram-negative and gram-positive bacterial strains. The findings support that these natural compounds can be used as a backbone structure to develop a broad spectrum of antibacterial agents.

Comparative Analysis of Clinical and Genomic Characteristics of Hypervirulent Klebsiella pneumoniae from Hospital and Community Settings: Experience from a Tertiary Healthcare Center in India.

Hypervirulent Klebsiella pneumoniae (hvKp) is a hypermucoviscous phenotype of classical Klebsiella pneumoniae (cKp) that causes serious infections in the community. The recent emergence of multidrug-resistant hvKp isolates (producing extended-spectrum beta-lactamases and carbapenemases) along with other virulence factors in health care settings has become a clinical crisis. Here, we aimed to compare the distribution of virulence determinants and antimicrobial resistance (AMR) genes in relation to various sequence types (STs) among the clinical hvKp isolates from both settings, to reinforce our understanding of their epidemiology and pathogenic potential. A total of 120 K. pneumoniae isolates confirmed by matrix-assisted laser desorption ionization-time of flight mass spectrometry were selected. hvKp was phenotypically identified by string test and genotypically confirmed by the presence of the iucA gene using PCR. Molecular characterization of hvKp isolates was done by whole-genome sequencing (WGS). Of the K. pneumoniae isolates, 11.6% (14/120) isolates were confirmed as hvKp by PCR (9.1% [11/120] string positive and 3.3% [4/120] positive by both methods); these were predominantly isolated from bloodstream infection (50%, 7/14), urinary tract infection (29%, 4/14), and respiratory tract infection (21%, 3/14). For all 14 hvKp infections, for 14.2% the source was in the community and for 85.7% the source was a health care setting. Two virulent plasmids were identified by WGS among the hvKp isolates from both settings. K64 was found to be the commonest capsular serotype (28.5%, 4/14), and ST2096 was the most common ST (28.5%, 4/14) by WGS. Two new STs were revealed: ST231 (reported to cause outbreaks) and ST43. The genome of one isolate was determined to be carrying AMR genes (blaCTX-M-15, blaNDM-1, blaNDM-5, blaOXA-181, blaOXA-232, etc.) in addition to virulence genes, highlighting the clonal spread of hvKp in both community and health care settings. IMPORTANCE To date, studies comparing the genomic characteristics of hospital- and community-acquired hvKp were very few in India. In this study, we analyzed the clinical and genomic characteristics of hvKp isolates from hospital and community settings. ST2096 was found as the most common ST along with novel STs ST231 and ST43. Our study also revealed the genome is simultaneously carrying AMR as well as virulence genes in isolates from both settings, highlighting the emergence of MDR hvKp STs integrated with virulence genes in both community and health care settings. Thus, hvKp may present a serious global threat, and essential steps are needed to prevent its further dissemination.

Comparison of Amsel's criteria with low and high Nugent's scores for the diagnosis of bacterial vaginosis.

Background: Bacterial vaginosis (BV) is the most common cause of vaginal discharge (VD) in women of reproductive age group. It is marked by displacement of beneficial Lactobacillus sp. by polymicrobial flora. BV is becoming a major public health concern as it is associated with adverse birth outcomes and increased susceptibility to sexually transmitted infections (STIs). Diagnosis of BV is currently done using clinical criteria (Amsel's) and the microbiological criteria (Nugent's scoring), the latter being the gold standard. Many out patient settings lack in microscopy facility and also skilled microbiologists, so reliance is placed on findings of clinical examination. Aims and Objectives: The aim of the study was to correlate Amsel's criteria with low (7-8) versus high (9-10) positive Nugent's scores for better understanding on utility of clinical criteria. Material and Methods: Patients with self-reported symptoms of vaginal discharge, genital itching were included and their pelvic examination was performed. Two swab samples were collected from lateral wall of vagina and posterior fornix and tested for BV infection using both Amsel's criteria and Nugent's score. Results: Of the total 125 women, 29 (23.2%) were positive for BV by Amsel's criteria, whereas 34 (27.2%) were positive by Nugent's scoring. Amsel's criteria showed a sensitivity of 100% with high Nugent's scores and 81% with low scores, thereby implying very few cases of diseased individuals being missed. Conclusion: This study demonstrates the continued utility of the Clinical criteria in outpatient setting as a screening test.

Azithromycin resistance and its molecular characteristics in Neisseria gonorrhoeae isolates from a tertiary care centre in North India.

Treatment guidelines for management of uncomplicated gonorrhoeae have been recently modified owing to alarming upsurge in azithromycin resistance. This study investigated the prevalence and genetic determinants of gonococcal azithromycin resistance in India. Four (5.7%) of 70 gonococcal isolates were resistant to azithromycin. Of 16 isolates investigated for molecular mechanisms of resistance, 13 (81.3%) and 6 (37.5%) isolates exhibited mutations in coding and promoter regions of mtrR gene, respectively. However, ermA, ermB and ermC genes or mutations in rrl gene were absent in all isolates. Azithromycin resistance is low in India posing no immediate threat to use of dual-therapy for syndromic management.