Recent pattern of antibiotic resistance in Staphylococcus aureus clinical isolates in Eastern India and the emergence of reduced susceptibility to vancomycin

Dramatic increase in antimicrobial resistance in ESKAPE clinical isolates over the 2010-2020 decade in India

RATIONALE AND OBJECTIVES

ESKAPE pathogens (Enterococcus faecium, Staphylococcus aureus, Klebsiella pneumoniae, Acinetobacter baumannii, Pseudomonas aeruginosa, and Enterobacter species) constitute a threat to humans worldwide. India is now the most populous country. The goal was to investigate the evolution of the rates of antimicrobial resistance in ESKAPE pathogens across India over the 2010-20 decade.

METHODS

The data (89 studies) were retrieved from the Medline PubMed repository using specific keywords.

RESULTS

The study of 20 177 ESKAPE isolates showed that A. baumannii isolates were the most represented (35.9%, n = 7238), followed by P. aeruginosa (25.3%, n = 5113), K. pneumoniae (19.5%, n = 3934), S. aureus (16.3%, n = 3286), E. faecium (2.6%, n = 517) and Enterobacter spp. (0.4%, n = 89). A notable increase in the resistance rates to antimicrobial agents occurred over the 2010-20 decade. The most important levels of resistance were observed in 2016-20 for A. baumannii (90% of resistance to the amoxicillin-clavulanate combination) and K. pneumoniae (81.6% of resistance to gentamycin). The rise in β-lactamase activities was correlated with an increase in the positivity of Gram-negative isolates for β-lactamase genes.

CONCLUSIONS

This review highlighted that, in contrast to developed countries that kept resistance levels under control, a considerable increase in resistance to various classes of antibiotics occurred in ESKAPE pathogens in India over the 2010-2020 decade.

Lipophilic bioactive compounds from thermophilic cyanobacterium Leptolyngbya sp. HNBGU-004: Implications for countering VRSA resistance

Extremophiles thrive in extreme conditions, showcasing rich and unexplored diversity. This resilience hints at the existence of novel biochemical pathways and unique bioactive compounds. In contrast, the issue of drug resistance and excessive misuse of antibiotics in various settings, such as healthcare, agriculture, and veterinary medicine, has contributed to the emergence and spread of drug-resistant microorganisms. In the present research, Leptolyngbya sp. HNBGU-004, was obtained from an extreme location, a hot water spring in the Garhwal Himalayan region of India. The lipophilic fraction derived from Leptolyngbya sp. HNBGU-004 exhibited significant inhibitory effects against vancomycin-resistant Staphylococcus aureus (VRSA), displaying a bactericidal concentration of 0.5 mg mL-1. Furthermore, gas chromatography-mass spectrometry (GC-MS) analysis of the lipophilic extract unveiled the major constituents. Leptolyngbya sp. HNBGU-004 holds significant promise as a primary source of potent anti-vancomycin-resistant S. aureus components. These findings emphasize the importance of Leptolyngbya sp. HNBGU-004 as a foundational source for use as both a synergistic and alternative agent against VRSA.

Antibiotic susceptibility of methicillin-resistant Staphylococcus aureus (MRSA) strains isolated at tertiary care hospital in Riyadh, Saudi Arabia

Staphylococcus aureus is an important human pathogen that has a major impact on public health. The objective of the present work was to determine the prevalence and the pattern of antibiotic susceptibility in S aureus (MRSA) isolates from the King Khalid University Hospital (KKUH) in Riyadh, Saudi Arabia. The isolates were collected from different body sites of infection and the antibiotic susceptibility was confirmed on the Vitek 2 system. A total of 371 MRSA isolates from clinical samples were received over a 12-month period from January 2021 to December 2021. The results showed that infection was predominant among males (55.8%) and most of the isolates occurred in the older age groups, with a mean age of 43.7 years and an age span from <1 to 89 years old. The majority (34.5%) recovered from wound infection followed by (14.6%) from blood. We have observed peaks of MRSA infections during the autumn, especially in September and November. All MRSA isolates were resistant to Amoxicillin + clavulanic acid, Ampicillin, Imipenem, Oxacillin, Cloxacillin, and Penicillin while all isolates were sensitive to Daptomycin and Nitrofurantoin. Furthermore, Vancomycin was resistant in (0.3%) of MRSA isolates, and (2.9%) was resistant to Linezolid. The current study concluded that MRSA strains had developed resistance toward 24 tested antibiotics, including the previous effective drugs vancomycin and linezolid. Therefore, there is an urgent need for continuous review of infection control practices to prevent any further spread of resistant strains.

Antimicrobial Resistance Patterns of Staphylococcus aureus and Enterococcus Species at the Ethiopian Public Health Institute, Ethiopia: A Five-Year Retrospective Analysis

Purpose

The study aimed to investigate the antimicrobial resistance patterns of Staphylococcus aureus and Enterococcus species isolated from clinical specimens over a period of five years, including resistance to methicillin and vancomycin.

Patients and Methods

Bacterial identification and antimicrobial susceptibility testing reports from 2017 to 2021 at the Ethiopian Public Health Institute were used for this retrospective study. The organisms were identified using either BD Phoenix M50, Vitek 2 compact, or conventional biochemical methods, whichever was available at the time of testing. The antimicrobial susceptibility profiles of the isolates were determined using either Kirby-Bauer disc diffusion, BD phoenix M50, or Vitek 2 compact. WHONET software was used to analyze the antimicrobial resistance patterns of both organisms. The p-values of ≤0.05 were considered statistically significant.

Results

During the study period, a total of 315 Staphylococcus aureus and 92 Enterococcus species were isolated. Out of 315 Staphylococcus aureus isolates, 27% and 5.1% were methicillin and vancomycin resistant, respectively. Staphylococcus aureus showed very high resistance to Penicillin G (86.7%). Out of 92 Enterococcus species recovered, 8.7% were vancomycin-resistant. Enterococcus species showed very high resistance to Penicillin G (71.4%) and tetracyclines (83.3%). Methicillin-resistant Staphylococcus aureus shows 100% resistance to penicillin followed by ciprofloxacin (50%), erythromycin (45.6%), and tetracycline (44.2%) and lower resistance to vancomycin (18.8%). All vancomycin-resistant isolates of both organisms were fully resistant (100%) to all antibiotics tested, except for linezolid and daptomycin, to which they were susceptible.

Conclusion

This study found a high prevalence of methicillin and vancomycin-resistant Staphylococcus aureus and vancomycin-resistant Enterococcus species between 2017 and 2021. However, there were no statistically significant changes in the prevalence of these organisms during the study period. This suggests that larger and more representative nationwide data is needed to show trends of these pathogens.

Epidemiology of Staphylococcus aureus Non-Susceptible to Vancomycin in South Asia

Staphylococcus aureus is one of the ESKAPE (Enterococcus faecium, Staphylococcus aureus, Klebsiella pneumoniae, Acinetobacter baumannii, Pseudomonas aeruginosa, and Enterobacter species) pathogens among which multidrug resistance has emerged. Resistance to methicillin has resulted in clinicians using the antibiotic of last resort, vancomycin, to treat infections caused by methicillin-resistant S. aureus (MRSA). However, excessive use and misuse of vancomycin are major causes of resistance among S. aureus strains. South Asia encompasses ~25% of the world's population, and countries in South Asia are often characterized as low- and middle-income with poor healthcare infrastructure that may contribute to the emergence of antibiotic resistance. Here, we briefly highlight the mechanism of vancomycin resistance, its emergence in S. aureus, and the molecular epidemiology of non-susceptible S. aureus to vancomycin in the South Asian region.

A study to explore the appropriateness of dosing regimen of vancomycin in critically ill patients in a tertiary care unit of India

Introduction

Vancomycin is used in proven or suspected MRSA and MRE infections. An AUC/MIC ratio of ≥400 is the current accepted critical PK/PD"efficacy" target of vancomycin activity. The present study was conducted to ascertain the appropriateness of practice of current dosage regimen of vancomycin (1 g BD) based on population pharmacokinetic approach.

Methods

A single-center prospective study with the ICU setting of a tertiary care center was conducted. A total of 15 adult patients with sepsis treated with vancomycin were included over 15 months from May 2019 to July 2020. Blood samples were obtained at 5, 10, and 30 minutes and thereafter at 2 and 6 hours following the completion of the vancomycin infusion. The data obtained from HPLC estimation was analyzed using a population pharmacokinetic approach with NLME, Phoenix 8.3.2.166. The pharmacokinetic model was based on covariates such as bodyweight and urinary creatinine clearance to predict drug concentrations.

Results

A total of 83 vancomycin blood samples were analyzed. The mean AUC_0-last and AUC_0-∞ in patients who improved and died were (AUC_(0-last)=293 (152.97); AUC_(0-∞)=535.14 (353.67) and (AUC_(0-last)=137.19 (51.37); AUC_(0-∞)=582.12 (1036.09) respectively, the difference between the two outcome groups was not statistically significant (p=0.104). The pharmacokinetic model was best described by a two-compartment linear model. The goodness-of-fit plots showed that the final covariate pharmacokinetic model (having bodyweight and urinary creatinine clearance) adequately described the observed vancomycin concentrations.

Conclusions

Based on the finding of the study it was concluded that 1 g BD dosing of vancomycin is inappropriate. Including covariates such as urinary creatinine clearance and weight in the pharmacokinetic model helped predict drug concentrations more accurately. However, further studies are required to demonstrate efficacy regarding applying this strategy.

Antimicrobial Resistance: The 'Other' Pandemic! : Based on 9th Dr. I. C. Verma Excellence Award for Young Pediatricians Delivered as Oration on 19th Sept. 2021

Antimicrobial resistance is projected to kill 10 million people by 2050. The biggest driver of antimicrobial resistance is excessive/unrestricted use of antimicrobials in humans and animals. Antimicrobial resistance is a problem in all types of pathogens including bacteria, mycobacteria, viruses, fungi, and parasites both globally and India and in both adults and children. The areas of greatest concern for India is the epidemic of MDR and XDR tuberculosis and resistance in gram-negative pathogens. The alarming rate of extended spectrum beta lactamase (ESBL) production in Enterobacteriales in both community and health care-associated infections is driving carbapenem use. Rates of carbapenem resistance are now significantly high in health care-associated gram negative pathogens with associated high mortality rates. The key solution to this antimicrobial resistance crisis needs participation of all stakeholders and lies in promoting rational antimicrobial therapy.

The Prevalence and Antimicrobial Susceptibility Pattern of Gram-Positive Pathogens: Three-Year Study at a Private Tertiary Care Hospital in Mumbai, India

Introduction  The growing resistance pattern of the gram-positive pathogens along with a steady increase in minimum inhibitory concentration of the currently available antibiotics have led to an increase in morbidity and mortality rates in India. This study aims to access the shifting antibiotic susceptibility paradigm of the gram-positive pathogens in various infections at a tertiary care center.

Methods  This is a 3-year retrospective observational study which was performed from January 2016 to December 2018 at a tertiary care hospital in Mumbai. All clinically significant gram-positive cocci isolated from a variety of clinical specimens were studied for their prevalence and antimicrobial susceptibility.

Results  Out of 4,428 gram-positive isolates, Staphylococcus aureus (35.3%) was the commonly encountered pathogen, followed by Enterococcus spp. (32.1%) and coagulase-negative Staphylococcus (CoNS) (25.7%). S. aureus was majorly isolated from skin and soft tissue infections (60.3%), followed by patients with respiratory tract infections (18.2%) and blood stream infections (13%). Among S. aureus , particularly methicillin-resistant S. aureus (MRSA), prevalence increased from 29.5% in 2016 to 35.1% in 2018, with an overall prevalence of 33.6%. All S. aureus isolates were 100% sensitive toward vancomycin, linezolid, tigecycline, and teicoplanin. However, the CoNS isolates showed a higher resistance rate with reduced susceptibility toward linezolid and teicoplanin. High prevalence of resistance was observed across gram-positive isolates with commonly used antibiotics such as ciprofloxacin, levofloxacin, and erythromycin. While the prevalence of linezolid-resistant enterococcus (LRE) was 3.6%, vancomycin (VRE) and teicoplanin resistance among the enterococcus species was as high as 7.7% and 7.5%, respectively.

Conclusion  Rising methicillin resistance among the Staphylococcal species (MRSA and MR-CoNS) along with reduced susceptibility toward currently available anti-MRSA agents is a matter of serious concern as it limits the therapeutic options for treating multidrug resistant (MDR) gram-positive infections.