Prevalence of carbapenemase-producing Klebsiella pneumoniae at a tertiary care hospital in Kathmandu, Nepal

Molecular detection of extended-spectrum β-lactamase- and carbapenemase-producing Klebsiella pneumoniae isolates in southwest Iran

OBJECTIVE

The global emergence of carbapenem-resistant Klebsiella pneumoniae is considered a significant contemporary concern., as carbapenems are the last resort for treating infections caused by multidrug-resistant Gram-negative bacteria. This study aimed to investigate the carbapenem-resistance genes in extended-spectrum β-lactamase producing K. pneumoniae isolates.

METHODS

Seventy-five non-duplicate clinical K. pneumoniae strains were isolated from urine, blood, sputum, and wound samples. Antimicrobial susceptibility tests for 12 different antibiotics were performed using the disk diffusion method, followed by determining minimum inhibitory concentrations of imipenem and meropenem. Phenotypic detection of extended-spectrum β-lactamase and carbapenemase enzymes was performed by double-disc synergy test and modified Hodge test, respectively. PCR assay further investigated resistant isolates for extended-spectrum β-lactamase and carbapenemase-encoding genes.

RESULTS

The highest and lowest resistance rates were observed against ampicillin (93.3%) and tigecycline (9.3%). According to phenotypic tests, 46.7% of isolates were positive for extended-spectrum β-lactamase enzymes and 52.8% for carbapenemase. A total of 11 isolates contained carbapenemase genes, with blaOXA-48 (19.4%; 7/36) being the predominant gene, followed by blaNDM (8.3%; 3/36).

CONCLUSION

The study's findings reveal the alarming prevalence of beta-lactamase enzymes in K. pneumoniae strains. Early detection of carbapenem-resistant isolates and effective infection control measures are necessary to minimise further spread, as carbapenem resistance has become a public health concern.

Phenotypic antibiotic susceptibility profile of clinical Enterobacteriaceae isolates from Kaduna State, northwest Nigeria

Background. The increasing resistance of clinical Enterobacteriaceae isolates to commonly prescribed antibiotics has been reported around the world. Data are generally lacking on the prevalence and antibiotic susceptibility profile of clinical Enterobacteriaceae isolates from Kaduna, northwest Nigeria. This study thus aimed to determine the diversity and antibiotic resistance profile of clinical Enterobacteriaceae isolates recovered from clinical specimens from patients admitted to two selected healthcare institutions in Kaduna. Methods. This was a prospective cross-sectional study conducted between September and December 2021. Non-duplicate clinical bacterial isolates recovered from various specimens were collected and identified using rapid biochemical identification kits. The susceptibility of identified Enterobacteriaceae to various antibiotics and phenotypic detection of carbapenemase enzymes were thereafter determined. The data were analysed and visualized using R software version 4.3.1. Results. Of the 500 bacterial isolates recovered from specimens collected for the purpose of clinical bacteriology diagnostics, 108 (21.6 %) were identified as Enterobacteriaceae, with Pantoea agglomerans (52, 48.1 %) and Klebsiella oxytoca (19, 17.6 %) being the most prevalent. The isolates exhibited high resistance to azithromycin (69 %) and ceftazidime (42 %), while exhibiting low resistance to amikacin (7 %) and imipenem (10 %). Among the carbapenem-resistant Enterobacteriaceae (CRE) isolates, a significant proportion (12/17, 70.6 %) tested positive for carbapenemase activity. Conclusion. This study reports a high prevalence of multidrug-resistant Enterobacteriaceae in Kaduna, northwest Nigeria. The emergence of pathogenic P. agglomerans and an alarmingly high prevalence of carbapenemase-producing CRE were also observed. The presence of carbapenemase producers in an area with low carbapenem usage and resistance rates raises significant concerns. Continuous surveillance and robust antibiotic stewardship policies are imperative to preserve the efficacy of carbapenems in this region.

Antibiotic resistance determinants among carbapenemase producing bacteria isolated from wastewaters of Kathmandu, Nepal

The emergence of carbapenem resistant bacteria (CRB) possesses a remarkable threat to the health of humans. CRB and carbapenem resistance genes (CRGs) have frequently been reported in clinical isolates from hospitals, however, their occurrence and distribution in wastewaters from various sources and river water have not been emphasized in Nepal. So, this study aimed to detect carbapenem resistant bacterial isolates and their resistance determinants in river water and different types of wastewaters. River water and both untreated and treated wastewater samples from hospitals, pharmaceutical industries, and municipal sewage were collected in summer and winter seasons. From 68 grab wastewater samples, CRB were detected only in 16 samples, which included eight hospital wastewater, and four each from untreated municipal sewage and river water. A total of 25 CRB isolates were detected with dominance of E. coli (44.0%) and K. pneumoniae (24.0%). The majority of the isolates harbored blaNDM-1 (76.0%), followed by blaOXA (36.0%) and blaKPC (20.0%) genes. Hospital wastewater majorly contributed to the presence of blaNDM-1, blaKPC, and blaOXA along with intI1 genes compared to river water and untreated municipal sewage, especially during the winter season. However, CRB were not detected in treated effluents of hospitals and municipal sewage, and both influents and effluents from pharmaceutical industries. The combined presence of each blaNDM-1 & blaOXA and blaKPC & blaOXA occurred in 16.0% of the bacterial isolates. The increased minimum inhibitory concentration (MIC) of meropenem was significantly associated with the presence of CRGs. The results of this study highlight the significance of carbapenem resistance in bacteria isolated from wastewater and river water, and underscore the necessity for efficient monitoring and control strategies to prevent the dispersion of carbapenem resistance in the environment and its potential consequences on human health.

Identification of Aztreonam as a potential antibacterial agent against Pasteurella multocida sialic acid binding protein: A combined in silico and in-vitro analysis

Pasteurella multocida, a Gram-negative zoonotic bacterial pathogen, interacts with the host environment, immune response, and infection through outer membrane proteins, adhesins, and sialic acid binding proteins. Sialic acids provide nutrition and mask bacterial identity, hindering the complement system, facilitates tissue access and biofilm formation. Sialic acid binding protein (SAB) enable adhesion to host cells, immune evasion, and nutrient acquisition, making them potential targets for preventing Pasteurella multocida infections. In this study, in silico molecular docking assessed 11 antibiotics targeting SAB (4MMP) comparing their docking scores to Amoxicillin. As SAB (4MMP) exhibits a highly conserved sequence in various Pasteurella multocida strains, including the specific strain PMR212 studied in this article, with a 96.09% similarity score. Aztreonam and Gentamicin displayed the highest docking scores (-6.025 and -5.718), followed by a 100ns molecular dynamics simulation. Aztreonam exhibited stable simulation with protein RMSD fluctuations of 1.8-2.2 Å. The ligand initially had an RMSD of 1.6 Å, stabilizing at 4.8 Å. Antibiotic sensitivity testing confirmed Aztreonam's efficacy with the largest inhibition zone of 42 mm, while Amoxicillin and Gentamicin had inhibition zones of 32 mm and 25 mm, respectively. According to CLSI guidelines, all three antibiotics were effective against Pasteurella multocida. Aztreonam's superior efficacy positions it as a promising candidate for further investigation in targeting Pasteurella multocida.

Beta-Lactamase-Producing Gram-Negative Bacterial Isolates Among the Patients Attending a Tertiary Care Hospital, Kathmandu, Nepal

Over the times, carbapenems have been the choice of drug for treating multidrug-resistant (MDR) and extended spectrum beta-lactamase (ESBL)-producing organisms. The current study aimed at determining the occurrence of metallo beta-lactamase (MBL) and AmpC beta-lactamase (ABL) in gram negative bacteria isolated from clinical samples. A cross-sectional study was conducted amongst the patients visiting Manmohan Memorial Medical College and Teaching Hospital (MMTH), Kathmandu, Nepal from August 2017 to January 2018. A total of 4351 samples including urine, pus, wound swab, endotracheal tip, catheter tip, and blood were collected from the patients and processed by standard conventional microbiological methods. Antibiotic susceptibility testing (AST) of the isolates was performed by Kirby-Bauer disk diffusion method. Double disc synergy test was performed on carbapenem resistant organisms to detect production of MBL and inhibitor-based test was used for the detection of ABL production. Of the 4351 samples, 421 bacterial isolates belonging to 16 different genera were recovered, of which 303 (71.97%) were Gram negative bacilli (GNB). E. coli (189/303) and S. aureus (80/118) were the most prevalent among gram negatives and gram positives, respectively. Bacterial incidence was found significantly associated with gender, specimen type, and the department where the patients were enrolled. Colistin-sulfate and polymycin-B were the most effective drug against GNB, whereas imipenem against gram positives. Prevalence of MDR and methicillin-resistant S. aureus (MRSA) was 35.15% and 60%, respectively. The prevalence of MBL and ABL-producing isolate was 11(3.6%) and 13(4.3%), respectively. Pseudomonas aeruginosa (5/11) and E. coli (9/13) were the major MBL and ABL producers, respectively. MBL and ABL production was found to be significantly associated with the age of the patient and the specimen type. A regular antibiotic surveillance activity with screening for MBL and ABL-producing bacterial isolates in the hospital settings to curb the incidence and transmission of such difficult-to-treat pathogens.

Bacterial Resistance in Hospital-Acquired Infections Acquired in the Intensive Care Unit: A Systematic Review

PURPOSE

In this review we present the status of the prevalence of bacteria resistant to antibiotics and the main antibiotic resistance genes that are reported in infections acquired in intensive care units (ICU) around the world.

METHODS

A systematic review based on the PRISMA guide was carried out, from the Science Direct, Redalyc, Scopus, Hinari, Scielo, Dialnet, PLOS, ProQuest, Taylor, Lilacs and PubMed/Medline databases. Inclusion criteria of this review were original research study published in a scientific journal in a 10-year time span from 1 January 2017 and 30 April 2022.

RESULTS

A total of 1686 studies were identified, but only 114 studies were considered eligible for inclusion. Klebsiella pneumoniae and Escherichia coli resistant to carbapenems and producers of extended-spectrum β-lactamases (ESBL) are the most frequently isolated pathogens in ICUs in Asia, Africa and Latin America. The blaOXA and blaCTX were antibiotic resistance genes (ARG) most commonly reported in different geographic regions (in 30 and 28 studies, respectively). Moreover, multidrug-resistant (MDR) strains were reported in higher frequency in hospital-acquired infections. Reports of MDR strains vary between continents, with the majority of publications being in Asia and between countries, with Egypt and Iran being highlighted. There is a predominance of few bacterial clones with MDR phenotype, for example, clonal complex 5 Methicillin-Resistant Staphylococcus aureus (CC5-MRSA) circulates frequently in hospitals in the United States, clone ST23-K. pneumoniae is reported in India and Iran, and clone ST260 carbapenemase-producing P. aeruginosa in the United States and Estonia.

CONCLUSION

Our systematic review reveals that ESBL- and carbapenemase-producing K. pneumoniae and E. coli are the most problematic bacteria that are reported, mainly in tertiary hospitals in Asia, Africa, and Latin America. We have also found propagation of dominant clones with a high degree of MDR, becoming a problem due to its high capacity to cause morbidity, mortality and additional hospital costs.

Occurrence and Resistance Pattern of Gram-Negative Bacteremia and Sepsis in A Tertiary Care Hospital - A Four-Year Study

The rise in antibiotic resistance has been a major source of public health concern. As a result, mortality and morbidity rates have risen significantly. This study was done to identify gram-negative organisms causing bacteremia/sepsis, study their prevalence rates, and antimicrobial resistance patterns, as evidence-based knowledge of gram-negative organisms causing sepsis and their resistance profiles is essential for effective hospital control and better management of infections caused by resistant bacteria. A retrospective study, conducted from January 2016 to December 2019, blood samples were collected using aseptic guidelines and cultured using automated blood culture methods. Biochemical tests were done according to microbiology standard procedures, while antimicrobial testing was done according to CLSI guidelines. A total of 13,808 blood samples were received within the study period of four years. Of the total, 2079 showed significant growth, with 765 being GNB isolates. The most common isolates were Escherichia coli (35.42%), Klebsiella pneumonia (19.74%), Acinetobacter species (9.67%), and other non-fermenting gram-negative bacilli (11.76%). Escherichia coli showed yearly resistance to aminoglycosides, cephalosporins, penicillin, fluoroquinolones, and B-lactam combination agents. Routine surveillance and awareness of the prevalence, etiological agents, and antibiotic resistance of gram-negative bacteria causing bacteremia/sepsis is critical for individual therapy, hospital control, and the effectiveness of preventive interventions.

Prevalence of Multidrug-Resistant Klebsiella pneumoniae Clinical Isolates in Nepal

Background

Multidrug-resistant Klebsiella pneumoniae (MDR-KP) are becoming increasingly common over the world. The focus of this research was to get a quantitative assessment of K. pneumoniae and their multidrug resistance (MDR) profile in Nepal.

Methods

Three electronic databases: PubMed, Google Scholar, and Research4Life were used to search publications specifying K. pneumoniae infections and/or their MDR status from January 2015 to October 2021. Preferred Reporting Items for Systematic Reviews and Meta-Analysis (PRISMA) guidelines was followed for the review, and R language 4.1.1 was used for analysis. Depending upon heterogeneity of data, we used random model for pooled data to examine the prevalence of the organism and the multidrug resistance.

Results

Evaluation included 16 studies, and the pooled estimation of K. pneumoniae in total clinical samples was 3% (95% CI; 0.01–0.05). In the meta-analysis, 14 studies were combined for determining the prevalence of K. pneumoniae in total positive clinical isolates which was 16% (95% CI: 0.11–0.20), while from 12 research studies, MDR status in the pathogen was found to be 64% (95% CI, 0.53–0.74).

Conclusion

The MDR status of K. pneumoniae as well as the prevalence of the bacteria in Nepal was analyzed which showed alarming situation about administration of antibiotics and indicated choosing and developing reliable antibiotic strategies.

Predominance of Acinetobacter spp., Harboring the blaIMP Gene, Contaminating the Hospital Environment in a Tertiary Hospital in Mwanza, Tanzania: A Cross-Sectional Laboratory-Based Study

Data on colonization and hospital contamination of carbapenem-resistant Gram-negative bacteria (CR-GNB) are limited in low- and middle-income countries. We designed this study to determine the prevalence and co-existence of carbapenemase genes among CR-GNB isolated from clinical, colonization, and hospital environmental samples at a tertiary hospital in Mwanza, Tanzania. The modified Hodge test (MHT), the combined disk test (CDT), and the double-disk synergy test (DDST) were used for the phenotypic detection of carbapenemases. A multiplex PCR assay was used to detect bla_IMP and bla_KPC, and a singleplex PCR assay was used to detect bla_OXA-48. Data were analyzed by STATA version 13.0. Overall, 68.8% (44/64) of the CR-GNB had at least one phenotype by phenotypic methods, whereby 60.9% (39/64) were both CDT and DDST positive and 31.3% (20/64) were MHT positive. A total of 23/64 (35.9%) had at least one of the genes tested with the predominance of bla_IMP (91.3%; 21/23). In addition, 47.7% (21/44) of the CR-GNB phenotypes had at least one gene. Around 47.8% (11/23) of the CR-GNB carried multiple genes encoding for carbapenem resistance, with the maximum co-existence of bla_IMP/bla_KPC/bla_OXA-48 (45.5%; 5/11). The majority of carbapenem-resistant genes were detected in Acinetobacter spp. (82.6%; 19/23) and isolated from bed swabs (69.6%; 16/23). Acinetobacter spp. carrying the bla_IMP gene predominantly contaminated the hospital environment. Therefore, we recommend routine decontamination of inanimate hospital surfaces, including patient beds.