Antibiotic resistance determinants and clonal relationships among multidrug-resistant isolates of Klebsiella pneumoniae

Molecular characterization of hypermucoviscous carbapenemase-encoding Klebsiella pneumoniae isolates from an Egyptian hospital

This study aimed to screen antibiotic resistance and virulence genes in carbapenem-resistant hypermucoviscous Klebsiella pneumoniae isolates from an Egyptian hospital. Among 38 previously confirmed carbapenem-nonsusceptible K. pneumoniae isolates, a string test identified three isolates as positive for hypermucoviscosity. Phenotypic characterization and molecular detection of carbapenemase- and virulence-encoding genes were performed. PCR-based multilocus sequence typing and phylogenetics were used to determine the clonality and global epidemiology of the strains. The coexistence of virulence and resistance genes in the isolates was analyzed statistically using a chi-square test. Three isolates showed the presence of carbapenemase-encoding genes (blaNDM, blaVIM, and blaIMP), adhesion genes (fim-H-1 and mrkD), and siderophore genes (entB); the isolates belonged to sequence types (STs) 101, 1310, and 1626. The relatedness between these sequence types and the sequence types of globally detected hypermucoviscous K. pneumoniae that also harbor carbapenemases was determined. Our analysis showed that the resistance and virulence profiles were not homogenous. Phylogenetically, different clones clustered together. There was no significant association between the presence of resistance and virulence genes in the isolates. There is a need for periodic surveillance of the healthcare settings in Egypt and globally to understand the true epidemiology of carbapenem-resistant, hypermucoviscous K. pneumoniae.

Similarity Analysis of Klebsiella pneumoniae Producing Carbapenemases Isolated from UTI and Other Infections

Klebsiella pneumoniae is an important opportunistic pathogen responsible for severe infections, mainly urinary tract infections (UTIs) and pneumonia. Hospital epidemic infections caused by multiresistant strains of carbapenemase-producing K. pneumoniae are the most concerning. NDM-producing strains are resistant to a wide range of antibiotics and have become the most significant threat. Determining the natural reservoirs and routes of infections is essential to end hospital outbreaks. Understanding the relatedness of K. pneumoniae strains is essential to determine the range and nature of the infection. The study compared phylogenetic relatedness between multiresistant K. pneumoniae strains isolated from hospitalized patients. Susceptibility to drugs and mechanisms of resistance were confirmed using phenotypic methods. PFGE was used to analyze the relatedness between strains. We analyzed 69 K. pneumoniae strains from various healthcare units. The isolates were mainly identified from urine. Strains were resistant to β-lactam antibiotics with β-lactamase inhibitors, cephalosporins, and quinolones. Their susceptibility to aminoglycosides and carbapenem antibiotics was diverse. Most of the isolated strains produced New Delhi metallo-ß-lactamase (NDM). Although K. pneumoniae strains were classified into several genotype clusters, closely related isolates were confirmed in the same hospital's wards, and in two hospitals in the same province.

Neonatal Sepsis: The impact of Hypervirulent Klebsiella pneumonia in a Tertiary Care Hospital

Neonatal sepsis is a blood-stream infection that affects newborns under the age of 28 days. Sepsis is common in NICUs and has a high prevalence of Klebsiella species. As a result, the study aims to find the antibiotic resistance profile, virulence factors, and the prognosis of K. pneumoniae-infected neonates. A prospective study was conducted which included 140 neonates with clinical sepsis. Characterization of Klebsiella pneumonia isolates was done by conventional methods. Drug resistance and virulence factors were detected by phenotypic methods. Genotypic methods included 16s rRNA amplification and sequencing. Detection of multidrug-resistant genes by PCR was performed. K. pneumoniae (26.9%) was the most common pathogen isolated. A high prevalence of ESBL was detected (58.8%). The prevalence of CRKP and MβL was about 29.4%, and 23.5% respectively. Two strains were Strong biofilm producers and nine isolates showed Beta hemolysis.7 strains were positive for the string test. Four strains were positive for the wcaG gene. 3 positive for magA (K1) and 2 were for gene wzy (K2). Three isolates carried blaCTX–M, four isolates harbored blaVIM, two for IMP, and one for NDM and KPC gene. K. pneumoniae isolates in the NICU increased in frequency and antibiotic resistance. It is a serious hazard to the healthcare system, and it necessitates strict infection control methods in healthcare settings, as well as antibiotic stewardship to prevent the overuse of antibiotics in neonatal sepsis.

Phenotypic and molecular characterization of extended-spectrum β-lactamase/AmpC- and carbapenemase-producing Klebsiella pneumoniae in Iran

BACKGROUND

The objective of the current study is to evaluate the phenotypic and molecular characterization of ESBL/AmpC- and carbapenemase-producing K. pneumoniae isolates in Iran.

METHODS

From October 2018 until the end of April 2020, different clinical samples were collected and K. pneumoniae isolates were identified using conventional biochemical tests and PCR assay. Antibiotic susceptibility pattern was determined using the Kirby-Bauer disk diffusion method. Modified Hedge Test (MHT) was applied to the identification of carbapenemase-producing K. pneumoniae. ESBL and AmpC-producing K. pneumoniae were detected using Double Disc Test (DDT) and Disc Potentiation Test (DPT), respectively. The presence of carbapenemase, ESBL, and AmpC encoding genes was screened by Polymerase Chain Reaction (PCR) assay.

RESULTS

A total of 100 K. pneumoniae isolates were collected. K. pneumoniae isolates had the highest resistance rate to cefazolin (66%) and cefotaxime (66%). Meropenem and amikacin with sensitivity rates of 76% and 69% were the most effective antimicrobial agents on K. pneumoniae isolates. It was found that 12 (12%), 27 (27%), and 9 (9%) K. pneumoniae isolates were positive in MHT, DDT, and DPT tests, respectively. Among the carbapenemase-encoding genes, bla_OXA-48 (24%) and bla_IMP (13%) genes had the highest frequency, while bla_KPC and bla_GIM genes were not detected among K. pneumoniae isolates. bla_TEM (48%) and bla_CMY (8%) genes had the highest frequency among ESBL and AmpC β-lactamase-encoding genes, respectively.

CONCLUSIONS

It is vital to adopt effective control strategies for K. pneumoniae infections and ensure rapid identification of antibiotic resistance profile.

Bacteriological profile and antimicrobial resistance patterns of burn wound infections in a tertiary care hospital

Background

The bacterial infections that prevail in the burnt patients continue to be a critical complication in the burnt patients and vary with time and place. Identification of bacterial pathogens with information of their antimicrobial susceptibility of burn wounds can help clinicians to select appropriate medication procedure as in providing them with suitable antibiotic for empirical treatment.

Methods

Retrospective study of thirty-one months (Jan 2015 to July 2017) was designed to evaluate bacteria involved in burnt wound infection and its antimicrobial susceptibilities in a Burn Intensive Care Unit of Eastern India. Pus samples were cultured on cysteine Lactose electrolyte deficient agar (Hi-Media, India). Positive bacteria cultures were identified and tested for antimicrobial susceptibility using VITEK®2 (bioMerieux, Durham, NC, USA) and interpreted according to Clinical Laboratory Standards Institute guidelines.

Results

Two hundred and seventy-two wound swabs from burnt patients were received, out of which 62.8% (n = 185) were revealed as positive for the presence of bacteria. Pseudomonas aeruginosa, Klebsiella pneumoniae, Acinetobacter baumannii and E. coli were discovered to be the most common organisms in patients. Isolated bacteria were least resistant to TIGECYCLINE and COLISTIN.

Conclusion

Data regarding the incidence of pathogens and their resistance patterns would benefit the clinicians to prescribe appropriate antibiotics, articulating policies for empirical antimicrobial therapy to control the different types of infections.

Draft Genome Sequences of Clinical and Nonclinical Isolates of Klebsiella spp. Exhibiting Nonheritable Tolerance toward Antimicrobial Compounds

A clinical isolate and a nonclinical isolate of Klebsiella pneumoniae were found to exhibit nonheritable tolerance in response to antimicrobial compounds. The draft genome sequences of both isolates are presented here.