Nosocomial infection by Klebsiella pneumoniae among neonates: a molecular epidemiological study

Treated wastewater: A hotspot for multidrug- and colistin-resistant Klebsiella pneumoniae

Wastewater treatment plants are hotspots for the release of antimicrobial resistant pathogenic bacteria into aquatic ecosystems, significantly contributing to the cycle of antimicrobial resistance. Special attention should be paid to antimicrobial resistant ESKAPE bacteria, which have been identified as high-priority targets for control measures. Among them, Klebsiella pneumoniae is particularly noteworthy. In this study, we collected wastewater samples from the inlet, sedimentation tank, and effluent water of a wastewater treatment plant in June, July, October, and November of 2018. We detected and characterized 42 K. pneumoniae strains using whole genome sequencing (15 from the inlet, 8 from the sedimentation tank, and 19 from the effluent). Additionally, the strains were tested for their antimicrobial resistance phenotype. Using whole genome sequencing no distinct patterns were observed in terms of their genetic profiles. All strains were resistant to tetracycline, meanwhile 60%, 47%, and 37.5% of strains isolated from the inlet, sedimentation tank, and effluent, respectively, were multidrug resistant. Some of the multidrug resistant isolates were also resistant to colistin, and nearly all tested positive for the eptB and arnT genes, which are associated with polymyxin resistance. Various antimicrobial resistance genes were linked to mobile genetic elements, and they did not correlate with detected virulence groups or defense systems. Overall, our results, although not quantitative, highlight that multidrug resistant K. pneumoniae strains, including those resistant to colistin and genetically unrelated, being discharged into aquatic ecosystems from wastewater treatment plants. This suggests the necessity of monitoring aimed at genetically characterizing these pathogenic bacteria.

Nanostructures for Delivery of Flavonoids with Antibacterial Potential against Klebsiella pneumoniae

Flavonoids are secondary metabolites that exhibit remarkable biological activities, including antimicrobial properties against Klebsiella pneumoniae, a pathogen responsible for several serious nosocomial infections. However, oral administration of these compounds faces considerable challenges, such as low bioavailability and chemical instability. Thus, the encapsulation of flavonoids in nanosystems emerges as a promising strategy to mitigate these limitations, offering protection against degradation; greater solubility; and, in some cases, controlled and targeted release. Different types of nanocarriers, such as polymeric nanoparticles, liposomes, and polymeric micelles, among others, have shown potential to increase the antimicrobial efficacy of flavonoids by reducing the therapeutic dose required and minimizing side effects. In addition, advances in nanotechnology enable co-encapsulation with other therapeutic agents and the development of systems responsive to more specific stimuli, optimizing treatment. In this context, the present article provides an updated review of the literature on flavonoids and the main nanocarriers used for delivering flavonoids with antibacterial properties against Klebsiella pneumoniae.

A New Casjensviridae Bacteriophage Isolated from Hospital Sewage for Inactivation of Biofilms of Carbapenem Resistant Klebsiella pneumoniae Clinical Isolates

Klebsiella pneumoniae, a member of the ESKAPE pathogen group, is a prominent cause of hospital-acquired infections. The WHO has recognized carbapenem-resistant K. pneumoniae as a critical-one priority pathogen. These resilient superbugs have the ability to form biofilms and present a significant global threat. In the present study, we isolated and characterized a bacteriophage SAKp02, from hospital sewage, infectious to carbapenem-resistant K. pneumoniae patient isolates. SAKp02 could infect 43 of 72 clinical isolates, indicating a broad host spectrum. Whole genome analysis classified SAKp02 within the family Casjensviridae, with a 59,343 bp genome encoding 82 ORFs. Comparative genomic analysis revealed significant differences between SAKp02 and its closest viruses, indicating a distinct genetic makeup positioning it as a novel phage strain within the lineage. The SAKp02 genome comprises bacteriolytic enzymes, including holin, endolysin, and phage depolymerase, crucial for bacterial lysis and biofilm disruption. It reduced biofilm biomass by over threefold compared to the control and eradicated 99% of viable cells within a 4 h treatment period. Scanning electron microscopy corroborated the ability of the phage to dismantle biofilm matrices and lyse bacterial cells. Safe and effective treatments are warranted, and hence, the fully characterized lytic phages with therapeutic potential against drug-resistant clinical isolates of bacteria are needed. Our study is the first to report the antibacterial and antibiofilm activity of Casjensviridae phages, and our discovery of a novel K. pneumoniae phage broadens the arsenal against the bacteria.

Exploring the resistome, virulome, and mobilome of multidrug-resistant Klebsiella pneumoniae isolates: deciphering the molecular basis of carbapenem resistance

BACKGROUND

Klebsiella pneumoniae, a notorious pathogen for causing nosocomial infections has become a major cause of neonatal septicemia, leading to high morbidity and mortality worldwide. This opportunistic bacterium has become highly resistant to antibiotics due to the widespread acquisition of genes encoding a variety of enzymes such as extended-spectrum beta-lactamases (ESBLs) and carbapenemases. We collected Klebsiella pneumoniae isolates from a local tertiary care hospital from February 2019-February 2021. To gain molecular insight into the resistome, virulome, and genetic environment of significant genes of multidrug-resistant K. pneumoniae isolates, we performed the short-read whole-genome sequencing of 10 K. pneumoniae isolates recovered from adult patients, neonates, and hospital tap water samples.

RESULTS

The draft genomes of the isolates varied in size, ranging from 5.48 to 5.96 Mbp suggesting the genome plasticity of this pathogen. Various genes conferring resistance to different classes of antibiotics e.g., aminoglycosides, quinolones, sulfonamides, tetracycline, and trimethoprim were identified in all sequenced isolates. The highest resistance was observed towards carbapenems, which has been putatively linked to the presence of both class B and class D carbapenemases, blaNDM, and blaOXA, respectively. Moreover, the biocide resistance gene qacEdelta1 was found in 6/10 of the sequenced strains. The sequenced isolates exhibited a broad range of sequence types and capsular types. The significant antibiotic resistance genes (ARGs) were bracketed by a variety of mobile genetic elements (MGEs). Various spontaneous mutations in genes other than the acquired antibiotic-resistance genes were observed, which play an indirect role in making these bugs resistant to antibiotics. Loss or deficiency of outer membrane porins, combined with ESBL production, played a significant role in carbapenem resistance in our sequenced isolates. Phylogenetic analysis revealed that the study isolates exhibited evolutionary relationships with strains from China, India, and the USA suggesting a shared evolutionary history and potential dissemination of similar genes amongst the isolates of different origins.

CONCLUSIONS

This study provides valuable insight into the presence of multiple mechanisms of carbapenem resistance in K. pneumoniae strains including the acquisition of multiple antibiotic-resistance genes through mobile genetic elements. Identification of rich mobilome yielded insightful information regarding the crucial role of insertion sequences, transposons, and integrons in shaping the genome of bacteria for the transmission of various resistance-associated genes. Multi-drug resistant isolates that had the fewest resistance genes exhibited a significant number of mutations. K. pneumoniae isolate from water source displayed comparable antibiotic resistance determinants to clinical isolates and the highest number of virulence-associated genes suggesting the possible interplay of ARGs amongst bacteria from different sources.

Hepatitis E virus and Klebsiella pneumoniae co-infection detected by metagenomics next-generation sequencing in a patient with central nervous system and bloodstream Infection: a case report

BACKGROUND

Hepatitis E virus (HEV) is the most common cause of acute viral hepatitis worldwide with major prevalence in the developing countries and can cause extrahepatic disease including the nervous system. Central nervous system infections caused by HEV are rare and caused by HEV together with other bacteria are even rarer.

CASE PRESENTATION

A 68-year-old man was admitted to the hospital due to a headache lasting for 6 days and a fever for 3 days. Lab tests showed significantly raised indicators of inflammation, cloudy cerebrospinal fluid, and liver dysfunction. Hepatitis E virus and Klebsiella pneumoniae were identified in the blood and cerebrospinal fluid using metagenomic next-generation sequencing. The patient received meropenem injection to treat K. pneumoniae infection, isoglycoside magnesium oxalate injection and polyene phosphatidylcholine injection for liver protection. After ten days of treatment, the patient improved and was discharged from the hospital.

CONCLUSION

Metagenomic next-generation sequencing, which can detect various types of microorganisms, is powerful for identifying complicated infections.

The dynamic evolution and IS26-mediated interspecies transfer of a blaNDM-1-bearing fusion plasmid leading to a hypervirulent carbapenem-resistant Klebsiella pneumoniae strain harbouring blaKPC-2 in a single patient

OBJECTIVES

To characterize the evolution and interspecies transfer of plasmids between Klebsiella pneumoniae and Escherichia coli within a single patient.

METHODS

Minimum inhibitory concentrations were measured using broth microdilution assays. Conjugation assays, string tests, and Galleria mellonella infection model experiments were also conducted. Whole-genome sequencing was performed on the Illumina and Nanopore platforms. Antimicrobial resistance determinants, insertion sequences, and virulence factors were identified using ABRicate/ResFinder database, ISFinder, and virulence factor database. Wzi and capsular polysaccharide (KL) were typed using Kleborate and Kaptive. Multi-locus sequence typing (MLST), replicon typing, and single nucleotide polymorphism analyses were conducted using the BacWGSTdb server.

RESULTS

The carbapenem-resistant K. pneumoniae 2111KP was characterized as ST11, wzi64, and KL64, with a positive string test result and a relatively high virulence phenotype. Analysis of the 2111KP genome revealed that blaNDM-1 was located in a 268,400-bp IncFIB/IncHI1B/IncX3 conjugative plasmid (p2111KP-1), regulated by IS26, IS5, and ISKox3. p2111KP-1 was also a rmpA2-associated virulence plasmid with an iutA-iucABCD gene cluster and a IS26-mediated multidrug-resistant fusion plasmid, which contained 8-bp (AGCTGCAC or GGCCTTTG) target site duplications. Segments flanked by IS26 of p2111KP-1 were 99.99% identical to a 49,016-bp E. coli plasmid.

CONCLUSIONS

This study provided direct evidence of plasmid fusion via IS26 between two different bacterial species within one patient and revealed the process by which genetic elements conferring carbapenem resistance and virulence were simultaneously transferred between these species. It highlights the need for strategic antibiotic use and rigorous monitoring to prevent the plasmid-mediated fusion and transmission of drug-resistance/virulence factors.

Prevalence and clonal diversity of carbapenem-resistant Klebsiella pneumoniae causing neonatal infections: A systematic review of 128 articles across 30 countries

BACKGROUND

Klebsiella pneumoniae is the most common pathogen causing neonatal infections, leading to high mortality worldwide. Along with increasing antimicrobial use in neonates, carbapenem-resistant K. pneumoniae (CRKP) has emerged as a severe challenge for infection control and treatment. However, no comprehensive systematic review is available to describe the global epidemiology of neonatal CRKP infections. We therefore performed a systematic review of available data worldwide and combined a genome-based analysis to address the prevalence, clonal diversity, and carbapenem resistance genes of CRKP causing neonatal infections.

METHODS AND FINDINGS

We performed a systematic review of studies reporting population-based neonatal infections caused by CRKP in combination with a genome-based analysis of all publicly available CRKP genomes with neonatal origins. We searched multiple databases (PubMed, Web of Science, Embase, Ovid MEDLINE, Cochrane, bioRxiv, and medRxiv) to identify studies that have reported data of neonatal CRKP infections up to June 30, 2022. We included studies addressing the prevalence of CRKP infections and colonization in neonates but excluded studies lacking the numbers of neonates, the geographical location, or independent data on Klebsiella or CRKP isolates. We used narrative synthesis for pooling data with JMP statistical software. We identified 8,558 articles and excluding those that did not meet inclusion criteria. We included 128 studies, none of which were preprints, comprising 127,583 neonates in 30 countries including 21 low- and middle-income countries (LMICs) for analysis. We found that bloodstream infection is the most common infection type in reported data. We estimated that the pooled global prevalence of CRKP infections in hospitalized neonates was 0.3% (95% confidence interval [CI], 0.2% to 0.3%). Based on 21 studies reporting patient outcomes, we found that the pooled mortality of neonatal CRKP infections was 22.9% (95% CI, 13.0% to 32.9%). A total of 535 neonatal CRKP genomes were identified from GenBank including Sequence Read Archive, of which 204 were not linked to any publications. We incorporated the 204 genomes with a literature review for understanding the species distribution, clonal diversity, and carbapenemase types. We identified 146 sequence types (STs) for neonatal CRKP strains and found that ST17, ST11, and ST15 were the 3 most common lineages. In particular, ST17 CRKP has been seen in neonates in 8 countries across 4 continents. The vast majority (75.3%) of the 1,592 neonatal CRKP strains available for analyzing carbapenemase have genes encoding metallo-β-lactamases and NDM (New Delhi metallo-β-lactamase) appeared to be the most common carbapenemase (64.3%). The main limitation of this study is the absence or scarcity of data from North America, South America, and Oceania.

CONCLUSIONS

CRKP contributes to a considerable number of neonatal infections and leads to significant neonatal mortality. Neonatal CRKP strains are highly diverse, while ST17 is globally prevalent and merits early detection for treatment and prevention. The dominance of blaNDM carbapenemase genes imposes challenges on therapeutic options in neonates and supports the continued inhibitor-related drug discovery.

The impact of the COVID-19 pandemic on nosocomial infections: a retrospective analysis in a tertiary maternal and child healthcare hospital

Objective

The constant changes in the control strategies of the Corona Virus Disease 2019 (COVID-19) pandemic have greatly affected the prevention and control of nosocomial infections (NIs). This study assessed the impact of these control strategies on the surveillance of NIs in a regional maternity hospital during the COVID-19 pandemic.

Methods

This retrospective study compared the observation indicators of nosocomial infections and their changing trends in the hospital before and during the COVID-19 pandemic.

Results

In total, 2,56,092 patients were admitted to the hospital during the study. During the COVID-19 pandemic, the main drug-resistant bacteria in hospitals were Escherichia coli, Streptococcus agalactiae, Staphylococcus aureus, Klebsiella pneumoniae, and Enterococcus faecalis. The detection rate of S. agalactiae increased annually, while that of E. faecalis remained the same. The detection rate of multidrug-resistant bacteria decreased during the pandemic (16.86 vs. 11.42%), especially that of CRKP (carbapenem-resistant Klebsiella pneumoniae 13.14 vs. 4.39, P < 0.001). The incidence of nosocomial infections in the pediatric surgery department decreased significantly (OR: 2.031, 95% CI: 1.405-2.934, P < 0.001). Regarding the source of infection, a significant reduction was observed in respiratory infections, followed by gastrointestinal infections. In the routine monitoring of the ICU, the incidence of central line-associated bloodstream infection (CLABSI) decreased significantly (9.4/1,000 catheter days vs. 2.2/1,000 catheter days, P < 0.001).

Conclusion

The incidence of nosocomial infections was lower than that before the COVID-19 pandemic. The prevention and control measures for the COVID-19 pandemic have reduced the number of nosocomial infections, especially respiratory, gastrointestinal, and catheter-related infections.

Antimicrobial Resistance Profile of Bacteria Causing Pediatric Infections at the University Teaching Hospital in Rwanda

Bacterial infections pose a global threat, especially in the pediatric population. Antimicrobials that are used to treat such infections continuously show reduced efficacy, and empirical therapy is a major treatment option in Rwanda. This study aimed to determine the resistance rate of commonly used antibiotics in pediatric patients. The study was conducted from June 1, 2018 to May 30, 2019, and microbiological samples were collected from 712 children with suspected bacterial infections. Antimicrobial sensitivity testing was performed on 177 positive cultures (24%) that were considered for data analysis. The findings show that the major bacterial isolates were Klebsiella pneumoniae (n = 50, 28.2%), Escherichia coli (n = 47, 26.5%), and Staphylococcus aureus (n = 38, 21.4%). In general, the greatest antibiotic resistance rate was observed in ampicillin (n = 125, 86.2%), amoxicillin-clavulanic acid (n = 84, 82.4%), amoxicillin (n = 64, 79%), cefadroxil (n = 83, 69.2%), tetracycline (n = 72, 59.7%), ceftazidime (n = 42, 55.3%), and cefuroxime (n = 14, 53.8%). More specifically, Klebsiella pneumoniae was 100% resistant to amoxicillin-clavulanic acid, cefuroxime, trimethoprim-sulfamethoxazole, ceftazidime, erythromycin, and clindamycin. Staphylococcus aureus was 86.7% resistant to ampicillin, and Escherichia coli was 91.7% resistant to tetracycline, 90.6% resistant to ampicillin, 83.3% resistant to amoxicillin-clavulanic acid, 79.3% resistant to cefadroxil, and 78.6% resistant to ceftazidime. Moreover, Klebsiella pneumoniae from blood and urine was 96.8% and 100% sensitive, respectively, to meropenem. Staphylococcus aureus from blood was 100% sensitive to vancomycin, whereas Escherichia coli from urine was sensitive to clindamycin (100%), nitrofurantoin (80.6%), and ciprofloxacin (72.7%). In conclusion, our findings show a high resistance rate to commonly used antibiotics, which suggests precaution in empirical therapy and continued surveillance of antimicrobial resistance.

A case–control study of infections caused by Klebsiella pneumoniae producing New Delhi metallo-beta-lactamase-1: Predictors and outcomes

Introduction

Infections caused by antimicrobial-resistant bacteria are a significant cause of death worldwide, and carbapenemase-producing bacteria are the principal agents. New Delhi metallo-beta-lactamase-1 producing Klebsiella pneumoniae (KP-NDM-1) is an extensively drug-resistant bacterium that has been previously reported in Mexico. Our aim was to conduct a case–control study to describe the risk factors associated with nosocomial infections caused by K. pneumoniae producing NDM-1 in a tertiary-care hospital in Mexico.

Methods

A retrospective case–control study with patients hospitalized from January 2012 to February 2018 at the Hospital Civil de Guadalajara “Fray Antonio Alcalde” was designed. During this period, 139 patients with a culture that was positive for K. pneumoniae NDM-1 (cases) and 486 patients hospitalized in the same department and on the same date as the cases (controls) were included. Data were analyzed using SPSS v. 24, and logistic regression analysis was conducted to calculate the risk factors for KP-NDM-1 infection.

Results

One hundred and thirty-nine case patients with a KP-NDM-1 isolate and 486 control patients were analyzed. In the case group, acute renal failure was a significant comorbidity, hospitalization days were extended, and significantly more deaths occurred. In a multivariate analysis of risk factors, the independent variables included the previous use of antibiotics (odds ratio, OR = 12.252), the use of a urinary catheter (OR = 5.985), the use of a central venous catheter (OR = 5.518), the use of mechanical ventilation (OR = 3.459), and the length of intensive care unit (ICU) stay (OR = 2.334) as predictors of infection with NDM-1 K. pneumoniae.

Conclusion

In this study, the previous use of antibiotics, the use of a urinary catheter, the use of a central venous catheter, the use of mechanical ventilation, and ICU stay were shown to be predictors of infection with NDM-1 K. pneumoniae and were independent risk factors for infection with NDM-1 K. pneumoniae.

Epidemiology and clinical characteristics of infection/colonization due to carbapenemase-producing Enterobacterales in neonatal patients

Background

The aim of this study was to elucidate the epidemiological features of carbapenemase-producing Enterobacterales (CPE) in the pediatric and neonatal patients, to describe clinical characteristics of neonatal patients with CPE infections, and to assess risk factors for neonatal rectal colonization with CPE.

Results

A total of 439 carbapenem-resistant Enterobacterales (CRE) isolates recovered from 367 infant patients were characterised, including 397 isolates of Klebsiella pneumoniae (KP) and 42 isolates of Escherichia coli (EC). Carbapenemase gene blaNDM-1 was the most commonly detected, accounting for 86.56% (n = 380), followed by blaKPC-2 (9.11%, 40) and blaIMP-4 (4.33%, 19). MLST analysis showed 17 different STs detected within CPKP isolates, with ST20, ST2068, ST36 and ST17 being the most frequently isolated types. Eleven STs were identified within CPEC isolates, with ST325 being the dominant types. Eight isolates of NDM-1 producing KP, belonging to ST23, were identified as having hypervirulent traits. The main infections caused by CPE were pneumonia (n = 90) and sepsis (n = 16). All infected patients received monotherapy, with meropenem and ciprofloxacin being the most commonly used antibiotics. All pneumonia patients were cured or improved after treatment. Of the 16 patients with sepsis, 9 were cured or improved, 3 died, and 4 abandoned treatment without any clinical improvement. The rectal prevalences of CPE in the 0–3 days old (DO), the 4–28 DO, and the 29 DO-1 year old groups were decreased from 15.31%, 27.37% and 14.29% in the first stool screening period to 11.78%, 19.59% and 4.07% in the second stool screening period, respectively. Multivariate analysis showed that cesarean section, acidosis, respiration failure, gastric lavage and enema were independent risk factors for rectal colonization in the 0–3 DO group, whereas cesarean section, cephalosporins, gastric lavage and residence in rural area were independently associated with rectal colonization in the 4–28 DO group. The implementation of a series of evidence-based control measures eventually contained the CPE transmission.

Conclusions

Continued vigilance, epidemiological studies, and multimodal infection prevention strategies are urgently needed due to frequent importations.

Molecular epidemiological characteristics of carbapenem-resistant Klebsiella pneumoniae among children in China

Klebsiella pneumoniae infection and antimicrobial resistance among children are major concerns. The occurrence of hypervirulent K. pneumoniae (hvKp) infections is gradually increasing worldwide, and disinfectant resistance is also being reported. Carbapenem- and disinfectant-resistant hvKp infection has made clinical treatment and nosocomial infection control among children increasingly challenging. In this study, whole-genome sequencing was conducted among 34 Carba NP-positive carbapenem-resistant K. pneumoniae (CRKP) strains, and the distribution of antibiotic resistance genes, virulence genes and disinfectant resistance genes was determined. Eleven distinct STs were identified, and most of them were ST11 (58.8%). Among the carbapenem resistance genes, KPC-2 was predominant (61.8%), followed by NDM-1 (26.5%) and IPM-4 (11.8%), and no other carbapenemase genes were found. Twelve virulence genes were investigated. All 34 CRKP strains carried the following virulence genes: rcsA/B, entA, fimA/H and mrkA/D. The gene iucB was present in only 3 (8.9%) CRKP strains. The positive detection rates of the iroN and ybtA genes were 94.1% and 64.7%, respectively. None of the strains was found to carry the rmpA and iroB genes. Two disinfectant resistance genes were investigated in this study. Twenty-one (61.8%) strains carried both the qacE and cepA disinfectant resistance genes, 13 (38.2%) CRKP strains carried only the cepA gene, and no strains with only the qacE gene was detected. The correlations among virulence, drug resistance and disinfectant tolerance showed that the virulence and disinfectant resistance genes were distinct among several types of carbapenemase-producing CRKP strains.

Surveillance of carbapenem-resistant Klebsiella pneumoniae in a paediatric hospital in China revealed the dynamics of carbapenemase and the prevalence of ST2735 K. pneumoniae

Background. Carbapenem-resistant Klebsiella pneumoniae (CRKP) is increasingly isolated in paediatric wards, posing a severe threat to these vulnerable populations. This study investigated the clinical features, determinants of carbapenem resistance and clonal relatedness among CRKP in our hospital.

Hypothesis. The prevalence of carbapenem-resistant K. pneumoniae in paediatric patients differs from the strains isolated from adult patients in carbapenemase and predominant clones.

Aim. To investigate the pattern of carbapenemase and the clonal relationships between carbapenem-resistant Klebsiella pneumoniae in a paediatric hospital in Jiangxi Province.

Methodology. Forty-five CRKP isolates were consecutively collected from October 2016 to October 2020. Medical records were reviewed to analyse clinical features. Detection of carbapenemase genes was used to determine CRKP resistance mechanisms and clonal relatedness among CRKP was identified through multi-locus sequence typing (MLST).

Results. Forty-three (95.6 %) patients developed CRKP infection, and two (4.4 %) were colonized by CRKP in the urinary tract. The overall mortality rate was 13.3 %. In total, 42 (93.3 %) strains were positive for carbapenemase genes, and bla NDM (62.2 %) was the predominant gene. The MLST identified 24 different sequence types (STs) of CRKP, in which ST11 (n=8, 17.8 %) and ST2735 (n=8, 17.8 %) were the most common STs.

Conclusion. The pattern of CRKP in paediatric patients reflects evolving changes. The ST2735 K. pneumoniae may present as a dangerous CRKP clone circulating in paediatric patients.

Antibiotic susceptibility patterns of pathogens isolated from laboratory specimens at Livingstone Central Hospital in Zambia

BACKGROUND

Multidrug resistance (MDR) is a global problem that require multifaceted effort to curb it. This study aimed to evaluate the antibiotic susceptibility patterns of routinely isolated bacteria at Livingstone Central Hospital (LCH).

METHODS

A retrospective study was performed on all isolated organisms from patient specimens that were processed from January 2019 to December 2021. Specimens were cultured on standard media and Kirby-Bauer disc diffusion method was employed for susceptibility testing following the Clinical and Laboratory Standard Institute's recommendations.

RESULTS

A total of 765 specimens were processed and only 500 (65.4%) met the inclusion criteria. Of the 500, 291(58.2%) specimens were received from female and from the age-group 17-39 years (253, 50.6%) and 40-80 years (145, 29%) in form of blood (331, 66.2%), urine (165, 33%) and sputum (4, 0.8%). Amongst the bacterial isolates, Staphylococcus aureus (142, 28.4%) was the commonest followed by Escherichia coli (91, 18.2%), and Enterobacter agglomerans (76, 15.2%), and Klebsiella pneumoniae (43, 8.6%). The resistance pattern revealed ampicillin (93%) as the least effective drug followed by oxacillin (88%), penicillin (85.6%), co-trimoxazole (81.5%), erythromycin (71.9%), nalidixic acid (68%), and ceftazidime (60%) whereas the most effective antibiotics were imipenem (14.5%), and piperacillin/tazobactam (16.7%). The screening of methicillin resistant Staphylococcus aureus (MRSA) with cefoxitin showed 23.7% (9/38) resistance.

CONCLUSION

Increased levels of MDR strains and rising numbers of MRSA strains were detected. Therefore, re-establishing of the empiric therapy is needed for proper patient management, studies to determine the levels of extended spectrum beta lactamase- and carbapenemase-producing bacteria are warranted.

CTX-M-15 Positive Escherichia coli and Klebsiella pneumoniae Outbreak in the Neonatal Intensive Care Unit of a Maternity Hospital in Ha'il, Saudi Arabia

Objective

The aim of this study was to retrospectively characterize E. coli and K. pneumoniae isolates obtained from neonates during a suspected NICU outbreak of infection in Ha’il, Saudi Arabia during a period of one month (April 2014).

Methods

Antibiotic susceptibility patterns, molecular characterization for antibiotic-resistant genes (blaTEM, blaSHV, and blaCTX-M), and genotyping by PFGE and MLST were performed.

Results

A total of 24 E. coli and 48 K. pneumoniae isolates were cultured from neonates that had been admitted to the NICU. Among E. coli, the majority of isolates (19/24) were ESBL-positive and all of these nineteen (100%) harbored the CTX-M-15 gene. A total of 15% (3/19) were co-producers of CTX-M-15 and SHV-12, and 68.4% (13/19) were co-producers of CTX-M-15 and TEM-1. Among K. pneumoniae isolates, 87.5% (42/48) were ESBL positive with 92.85% (39/42) of these isolates containing the CTX-M-15 gene. A total of 97% (38/39) of K. pneumoniae were co-producers of CTX-M-15 and SHV-12, and 88% (37/42) were positive for TEM-1. Furthermore, 85.7% (36/42) K. pneumoniae were co-producers of CTX-M-15 and TEM-1. The majority of E. coli isolates (18/19 isolates) were grouped into two genetic clusters by pulsed field gel electrophoresis (PFGE) and all the isolates were found to be ST-131 type. In contrast, K. pneumoniae (31/42) isolates belonged to a single genotypic lineage, and all (100%) isolates belonged to the ST-14 type.

Conclusion

This is the first report of CTX-M-15-positive, ESBL E. coli, and K. pneumoniae isolates recovered from an outbreak in an NICU in Ha’il, Saudi Arabia. It is alarming to note the high rate of outbreak isolates with simultaneous production of CTX-M-15 and SHV-12 conferring high-level resistance to oxyimino-cephalosporins.