Prevalence of anaerobic bacteria in surgical site infections in Lagos University Teaching Hospital

Background

Surgical site infection (SSI) is the second most common cause of nosocomial infection, after urinary tract infection. Sequelae of SSI include increased healthcare costs and worse patient outcomes. There is a paucity of research studies on the impact of anaerobic organisms on SSIs in Nigeria. The aim of this study was to determine the role of anaerobic bacteria in SSI encountered at the Lagos University Teaching Hospital (LUTH).

Materials and Methods

A total of 438 patients were consecutively recruited into this study from general surgery, obstetrics and gynaecology and paediatric units of the LUTH from 1 July through 31 December 2019. Two surgical wound specimens were collected from all patients with suspected SSIs. One was for anaerobic culture using Brucella blood agar incubated in an anaerobic jar that secured anaerobiosis using the anaerobic gas pack. The other swab was used for aerobic culture on blood agar incubated on air at 37oC. Identifications and antibiotic sensitivity testing were performed according to standard laboratory procedures.

Result

The overall incidence of SSI in the study was 12.3%. The incidence of anaerobic SSI was 1.1%. The distribution of anaerobic infections by medical specialty unit was as follows; general surgery (1.6%), obstetrics and gynaecology (0.8%) and paediatrics (0.9%). Bacteroides species was the only anaerobic isolate. The risk factors associated with the development of SSI by multiple logistic regression analysis were duration of surgery greater than 2 h (OR 1.418; 95% CI 1.834-9.286; P = 0.001) and NNIS risk index 2 and 3 - (OR 2.165; 95% CI 2.366-32.086; P = 0.001).

Conclusions

The prevalence of anaerobic SSI was 1.1%. Duration of surgery greater than 2 h and NNIS risk index 2 and 3 were independent predictors of SSI.

The whole-genome molecular epidemiology of sequential isolates of Acinetobacter baumannii colonizing the rectum of patients in an adult intensive care unit of a tertiary hospital

IMPORTANCE

Acinetobacter baumannii is a multidrug-resistant nosocomial pathogen that colonizes and infects debilitated patients in the ICU. There is very little information on the genomic characteristics of colonizing strains. This information is important to understand the evolution of lineages of A. baumannii that develop resistance while patients receive antibiotic treatment in the ICU. Our study demonstrated different patterns of colonization of the rectum of ICU patients with different STs of A. baumannii while one ST colonized all patients. Some STs carried more antibiotic resistance genes compared to others. However, there was a correlation between ST and a particular resistance gene profile. Our results further elucidate the dynamics of enteric colonization of this opportunistic pathogen.

Cracking the Code: Unveiling the Diversity of Carbapenem-Resistant Klebsiella pneumoniae Clones in the Arabian Peninsula through Genomic Surveillance

The rise of antimicrobial resistance is a global challenge that requires a coordinated effort to address. In this study, we examined the genetic similarity of carbapenem-resistant Klebsiella pneumoniae (CRKP) in countries belonging to the Gulf Cooperation Council (GCC) to gain a better understanding of how these bacteria are spreading and evolving in the region. We used in silico genomic tools to investigate the occurrence and prevalence of different types of carbapenemases and their relationship to specific sequence types (STs) of CRKP commonly found in the region. We analyzed 720 publicly available genomes of multi-drug resistant K. pneumoniae isolates collected from six GCC countries between 2011 and 2020. Our findings showed that ST-14 and ST-231 were the most common STs, and 51.7% of the isolates carried bla_OXA-48-like genes. Additionally, we identified rare carbapenemase genes in a small number of isolates. We observed a clonal outbreak of ST-231 in Oman, and four Saudi isolates were found to have colistin resistance genes. Our study offers a comprehensive overview of the genetic diversity and resistance mechanisms of CRKP isolates in the GCC region that could aid in developing targeted interventions to combat this pressing global issue.

Elucidating the virulence genes harboured by carbapenemase- and non-carbapenemase-producing carbapenem-resistant Klebsiella pneumoniae rectal isolates from patients admitted to intensive care units using whole-genome sequencing in Kuwait

Introduction. Klebsiella pneumoniae is a Gram-negative pathogen responsible for community- and nosocomial-acquired infections. The presence of an accessory genome determines the bacterial pathogenicity and the host immune response, and thus indicates multidrug-resistant strains or more virulent groups. Little is known about the virulence genes in K. pneumoniae in Kuwait.Hypothesis/Gap Statement. The diversity of virulence genes and capsule loci in K. pneumoniae isolates warrants further genomic studies to better understand their transmission within the hospitals in Kuwait.Aim. We aimed to investigate the virulence genes harboured by K. pneumoniae isolated from rectal swabs of intensive care unit (ICU) patients in two Kuwaiti teaching hospitals.Methodology. Six isolates from patients in the ICUs of Al Razi and Mubarak hospitals, designated RZH144, RZH132 RZH108 and RZH173, and MKH381 and MKH347, respectively, were subjected to whole-genome sequencing (WGS) assays. RZH144 and RZH132 were non-carbapenemase-producing K. pneumoniae (NCKP) isolates negative for genes encoding carbapenemase production by PCR assays, and the remaining four were carbapenemase-producing K. pneumoniae (CPKP) isolates. Isolates were characterized by phenotypic, PCR and WGS methods. Susceptibility testing was performed by E test and clonality by multilocus sequence typing. Analysis of the isolates' assembled contigs was carried out using Kleborate (https://pathogen.watch).Results. An NCPE RZH132 K. pneumoniae isolate belonged to ST231-wzi104 and harboured gene clusters encoding the biosynthesis of the siderophore aerobactin (iuc5) on 62-3LV. The capsular locus variants were KL51 and O locus O1v2. Another NCPKP RZH144 isolate was confirmed as ST43-wzi412 and harboured KL61 and O1v1. The four CPKP isolates harboured two virulence loci - ybt14 and iuc5 - encoding the siderophores yersiniabactin and aerobactin, respectively. They belonged to ST231-wzi104 and harboured yersiniabactin on ICEKp5. The sequence type of ybt was YbST145-1LV. Strain RZ108 was devoid of virulence loci. Its sequence type was ST15-wzi151 and harboured KL48 and O1V1. ST231 clonal lineage isolates shared common virulence plasmid variants.Conclusion. The CPKP ST231 had the highest virulence score and contained iuc5, which was found for the first time in ST231-CPKP isolates in Kuwait.

Multiplex gyrB PCR Assay for Identification of Acinetobacter baumannii Is Validated by Whole Genome Sequence-Based Assays

OBJECTIVE

A multiplex gyrB PCR assay has been used to diagnose Acinetobacter baumannii. However, this assay has not been validated against the gold standard DNA-DNA hybridization assay, which is a laborious method. DNA-DNA hybridization assay is now replaced by whole genome sequence (WGS)-based methods. Two such methods are a k-mer-based search of sequence reads using the Kraken 2 program and average nucleotide identity (ANI). The objective was to validate the gyrB PCR assay with WGS-based methods.

SUBJECTS AND METHODS

We cultured 270 sequential A. baumannii isolates from the rectal swabs of 32 adult patients. The identity of the isolates was determined by gyrB PCR. The sequences of 269 isolates were determined by Illumina sequencing and the taxonomy was inferred by the Kraken 2 program and ANI.

RESULTS

All the 269 isolates were confirmed as A. baumannii by Kraken 2 and ANI.

CONCLUSION

The gyrB PCR assay is now validated for easy identification of A. baumannii in comparison with gold standard WGS-based assays.

Preponderance of bla KPC-Carrying Carbapenem-Resistant Enterobacterales Among Fecal Isolates From Community Food Handlers in Kuwait

Carbapenem-resistant Enterobacterales (CRE) are pathogens that have been found in several countries, with a significant public health concern. Characterizing the mode of resistance and determining the prevailing clones are vital to the epidemiology of CRE in our community. This study was conducted to characterize the molecular mode of resistance and to determine the clonality of the CRE fecal isolates among community food handlers (FHs) vs. infected control patients (ICPs) in Kuwait. Fecal CRE isolates obtained from FHs and ICPs from September 2016 to September 2018 were analyzed for their resistance genes. Gene characterization was carried out by polymerase chain reaction (PCR) assays and sequencing. Clonality of isolates was established by multilocus sequence typing (MLST). Of the 681 and 95 isolates of the family Enterobacterales isolated from FHs and ICPs, 425 (62.4%) and 16 (16.8%) were Escherichia coli, and 18 (2.6%) and 69 (72.6%) were Klebsiella pneumoniae, respectively. A total of 36 isolates were CRE with a prevalence of 5.3% among FH isolates and 87 (91.6%) among the ICPs. Of these, carbapenemase genes were detected in 22 (61.1%) and 65 (74.7%) isolates, respectively (p < 0.05). The detected specific genes among FHs and ICPs were positive for bla_KPC 19 (86.4%) and 35 (40.2%), and bla_OXA 10 (45.5%) and 59 (67.8%), in addition to bla_NDM 2 (9.1%) and 32 (36.8%), respectively. MLST assays of the E. coli and K. pneumoniae isolates revealed considerable genetic diversity and polyclonality as well as demonstrated multiple known ST types and eight novel sequence types. The study revealed a relatively high number of CRE harboring predominantly bla_KPC-mediated CRE among the community FH isolates vs. predominant bla_OXA genes among the ICPs. Those heterogeneous CRE isolates raise concerns and mandate more efforts toward molecular surveillance. A multinational study is recommended to monitor the spread of genes mediating CRE in the community of Arabian Peninsula countries.

Molecular characterization of rectal isolates of carbapenemase-negative carbapenem-resistant enterobacterales obtained from ICU patients in Kuwait by whole-genome sequencing

Introduction. Carbapenem-resistant enterobacterales (CRE) are listed among the most urgent antibiotic resistance threats.Hypothesis. Previous studies on the mechanisms of CRE in Kuwait have focused on carbapenemases. There have been no studies on non-carbapenemase-producing CRE in Kuwait.Aim/Gap Statement. The aim of this study was to investigate the genetic characteristics of non-carbapenemase-producing carbapenem-resistant enterobacterales (NCPE) isolates using whole-genome sequencing (WGS).Methodology. Fourteen confirmed NCPE isolates that were negative for genes encoding carbapenemase production by polymerase chain reaction (PCR) assays using rectal swabs from intensive care unit patients were characterized using phenotypic, PCR and WGS methods. Susceptibility testing was performed via Etest and clonality via multi-locus sequence typing (MLST).Results. All of the isolates were resistant to ertapenem; 78.6 % were resistant to imipenem, meropenem and trimethoprim-sulfamethoxazole. Resistance to the other antibiotics was variable, ranging from 28.5 (colistin) through 50 (tigecycline) and 64.3 (amikacin) up to 85.7 % against both amoxicillin-clavulanic acid and ciprofloxacin. WGS detected several resistance genes mediating the production of β-lactamases, genes encoding an outer-membrane porin permeability mutation resulting in reduced susceptibility to β-lactams, including carbapenems, and genes for multidrug-resistant (MDR) efflux pumps. The isolates also possessed global activator protein MarA, which mediated reduced permeability to β-lactams. The existence of β-lactamase genes, overexpression of MDR efflux pumps and reduced permeability mediated by the porin genes were responsible for carbapenem resistance.Conclusions. This finding reflects the superior detection capabilities offered by WGS analysis, which can be used to complement traditional methods and overcome their limited resolution in clinical settings.

Molecular characterization of metronidazole resistant Bacteroides strains from Kuwait

Eleven metronidazole resistant Bacteroides and one newly classified Phocaeicola dorei strain from Kuwait were investigated for their resistance mechanisms and the emergence of their resistant plasmids. All but one strain harbored nimE genes on differently sized plasmids. Of the 11 nimE genes, 9 were preceded by full copies of the prototype ISBf6 insertion sequence element, one carried a truncated ISBf6 and one was activated by an additional copy of IS612B. Nucleotide sequencing results showed that the nimE ISBf6 distances were constant and all five different plasmids shared a common region, suggesting that (i) the nimE-ISBf6 configuration was inserted into an undisclosed common genetic element, (ii) over time, this common element was mutated by insertions and deletions, spreading the resultant plasmids. Of the 10 B. fragilis strains in this collection, 6 were also cfiA-positive, one with full imipenem resistance, indicating a tendency for multidrug resistance (MDR) among such isolates. The significant number of metronidazole resistant Bacteroides spp. and P. dorei strains with the MDR phenotype warns of difficulties in treatment and suggests promoting adherence to antibiotic stewardship recommendations in Kuwait.

Monitoring antibiotic resistance profiles of faecal isolates of Enterobacteriaceae and the prevalence of carbapenem-resistant isolates among food handlers in Kuwait

OBJECTIVES

Carbapenem-resistant Enterobacteriaceae (CRE) have become one of the most challenging problems in infectious diseases worldwide. Unrecognised personnel such as food handlers (FHs) colonised with CRE serve as a reservoir for transmission. This study assessed the prevalence and susceptibility patterns of CRE isolates from FHs working in commercial eateries in the community (CFHs) and healthcare settings (HCFHs) in Kuwait over the period 2016-2018.

METHODS

Representative colonies from faecal samples were identified by API 20E and a VITEK®2 ID System. Susceptibility testing against 21 antibiotics was performed by Etest and agar dilution.

RESULTS

A total of 681 isolates of the family Enterobacteriaceae were isolated from 405 FHs, of which 425 (62.4%) were Escherichia coli and 126 (18.5%) were Klebsiella pneumoniae. The prevalence of CRE among FHs was 7.7% (31/405), comprising 32% CFHs (10/31) and 68% HCFHs (21/31). Ampicillin, tetracycline and cefalotin showed very poor activities against most isolates with resistance rates of 63.3%, 41.7% and 40.8%, respectively. The prevalence of multidrug-resistant (MDR) isolates was 30.5%, including 130 E. coli (30.6%) and 22 K. pneumoniae (17.5%). An alarming level of colistin resistance (11.3%) was noted. A significant proportion of FH isolates (13.2%) exhibited extended-spectrum β-lactamases (ESBL) phenotypes, including 80 E. coli (18.8%) and 5 K. pneumoniae (4.0%).

CONCLUSION

This study revealed that asymptomatic intestinal carriage of CRE, including MDR and ESBL isolates, was relatively common in our community. It is conceivable that FHs may pose a significant risk to consumers for the acquisition and spread of resistant strains.

Multicentre study of the burden of multidrug-resistant bacteria in the aetiology of infected diabetic foot ulcers

Background

Infected diabetic foot ulcer (IDFU) is a public health issue and the leading cause of non-traumatic limb amputation. Very few published data on IDFU exist in most West African countries.

Objective

The study investigated the aetiology and antibacterial drug resistance burden of IDFU in tertiary hospitals in Osun state, Nigeria, between July 2016 and April 2017.

Methods

Isolates were cultured from tissue biopsies or aspirates collected from patients with IDFU. Bacterial identification, antibiotic susceptibility testing and phenotypic detection of extended-spectrum beta-lactamase and carbapenemase production were done by established protocols. Specific resistance genes were detected by polymerase chain reaction.

Results

There were 218 microorganisms isolated from 93 IDFUs, comprising 129 (59.2%) Gram-negative bacilli (GNB), 59 (27.1%) Gram-positive cocci and 29 (13.3%) anaerobic bacteria. The top five facultative anaerobic bacteria isolated were: Staphylococcus aureus (34; 15.6%), Escherichia coli (23; 10.6%), Pseudomonas aeruginosa (20; 9.2%), Klebsiella pneumoniae (19; 8.7%) and Citrobacter spp. (19; 8.7%). The most common anaerobes were Bacteroides spp. (7; 3.2%) and Peptostreptococcus anaerobius (6; 2.8%). Seventy-four IDFUs (80%) were infected by multidrug-resistant bacteria, predominantly methicillin-resistant S. aureus and GNB producing extended-spectrum β-lactamases, mainly of the CTX-M variety. Only 4 (3.1%) GNB produced carbapenemases encoded predominantly by bla _VIM. Factors associated with presence of multidrug-resistant bacteria were peripheral neuropathy (adjusted odds ratio [AOR] = 4.05, p = 0.04) and duration of foot infection of more than 1 month (AOR = 7.63, p = 0.02).

Conclusion

Multidrug-resistant facultative anaerobic bacteria are overrepresented as agents of IDFU. A relatively low proportion of the aetiological agents were anaerobic bacteria.

Evaluating Food Safety Compliance and Hygiene Practices of Food Handlers Working in Community and Healthcare Settings in Kuwait

Safe food handling and proper hygiene practices performed by food handlers (FHs) in catering establishments are fundamental elements in reducing foodborne diseases. This study aimed at assessing food safety knowledge and compliance of hygiene practices of FHs within food establishments (using a structured questionnaire). A cross-sectional study was carried out from May 2016 to March 2018 on FHs working in community and healthcare settings. A total of 405 FHs, including 44.9% and 55.1%, were working in community and healthcare settings, respectively. The majority, 84.7%, were males with a ratio of 5.5:1. Most of them, 84.4%, had a high school education and above. A greater number, 44%, of FHs were in the age bracket of 29-39 years. As high as 95.6% of them underwent a regular medical check-up. Unsafe attitudes were shown by 44.9%% who used the same hand gloves while handling raw meat and fresh food. Additionally, 42% went home with their uniforms. The hygiene assessment score was 95.8%. In general, FHs have adequate knowledge and compliance with food safety practices. It is recommended that regular and ongoing training on hygienic practices and proper food safety techniques must be given to all FHs to ensure food safety.

Prevalence of carbapenem-resistant Enterobacteriaceae and emergence of high rectal colonization rates of blaOXA-181-positive isolates in patients admitted to two major hospital intensive care units in Kuwait

BACKGROUND

Fecal colonization by carbapenem-resistant Enterobacteriaceae (CRE) can be the main reservoir for transmission of these resistant organisms especially in the Intensive Care Units (ICUs).

AIM

This study was conducted to evaluate the rate of rectal carriage and molecular characterization of CRE in patients hospitalized in the ICUs of 2 major hospitals (Adan and Mubarak Al Kabeer Hospitals) in Kuwait.

MATERIALS AND METHODS

Rectal swabs were collected from all patients at admission, 48 h after admission and once weekly from April 2017- March 2018. Initial CRE screening was carried out on MacConkey agar on which meropenem disc 10μg was placed. Identification of isolates was by API 20E. Susceptibility testing was performed using the E-test method. Polymerase chain reaction (PCR) was used to detect the carbapenemase-encoding genes. Clonal relationship was investigated by pulsed-field electrophoresis (PFGE). Genes of blaOXA-181 and blaNDM-5-carrying plasmids were detected in some strains.

RESULTS

A total of 590 patients were recruited into the study. Of these, 58 were positive for CRE, giving a prevalence of 9.8%; 25/320 (7.8%) in Adan and 33/270 (12.2%) in Mubarak Al Kabeer Hospitals. All isolates were resistant to multiple antibiotics. Resistance rates to colistin and tigecycline were 17% and 83%, respectively. Single genes of blaOXA-181 were detected in isolates from 38 (65.5%) out of 58 patients and in 5 patients colonized by blaOXA-48-positive CRE. A combination of 2 genes was detected in 12 isolates; 5 blaKPC-2 and blaOXA-181, 4 blaVIM-1 and blaOXA-181, and 3 blaNDM-5 and blaOXA-181. PFGE showed an overall level of similarity of 38%. Southern hybridization studies localized the blaOXA-181 and blaNDM-5 genes to a large plasmid of 200kb in 3 K. pneumoniae isolates and a small plasmid of 80kb in 2 E. coli isolates, respectively.

CONCLUSION

The prevalence of CRE colonization in the 2 hospital ICUs was relatively high and the emergence of blaOXA-181-mediated CRE is a cause for concern as there is the possibility of rapid horizontal spread among hospital patients in Kuwait. Active surveillance of CRE in the ICUs is highly recommended to stem its spread.

Antimicrobial Resistance of Serial Isolates of Acinetobacter baumannii Colonizing the Rectum of Adult Intensive Care Unit Patients in a Teaching Hospital in Kuwait

Objectives: Outbreak and endemic isolates of Acinetobacter baumannii are known to be polyclonal. In an ongoing study, we hypothesized that the patient gut was the source of the polyclonality where genetic exchanges take place. To test the hypothesis, we collected 270 serial rectal isolates from 32 adult intensive care unit patients over 16 months and investigated their drug resistance profiles. Methods: Antimicrobial susceptibility was determined according to recommended methods. The bla_IMP, bla_VIM, bla_SIM, bla_OXA-23, bla_OXA-24/40, bla_OXA-51, bla_OXA-48, bla_KPC, bla_GES, bla_NDM and bla_OXA-58 were sought by PCR. A subset of 42 isolates were studied for plasmid-mediated resistance. Results: Most of the 270 isolates were multidrug resistant (MDR; with resistances to meropenem of 85.18% and imipenem of 87.04%), but susceptible to colistin and trimethoprim/sulfamethoxazole. There was no correlation between the pattern of resistance and antibiotics administered to treat infections. There was no consistent pattern of resistance or content of carbapenemase genes in serial rectal isolates suggesting polyclonality of the isolates. Genes mediating production of OXA-23, OXA-24/40, IMP, and GES enzymes were carried on plasmids and they mediated resistance to all carbapenems in conjugation studies. Conclusion: A. baumannii colonizing the rectum were polyclonal, MDR, and carbapenem resistance genes were found on plasmids and some plasmids were transferable.

Genetic relatedness of serial rectal isolates of Acinetobacter baumannii in an adult intensive care unit of a tertiary hospital in Kuwait

Acinetobacter baumannii is an opportunistic pathogen of intensive care unit (ICU) patients. A. baumannii colonizes many parts of the body including the gastrointestinal tract. Endemic and epidemic strains are polyclonal. There is no clarity on the origin of polyclonality of A. baumannii. The objective of the study was to define the genetic relatedness of serial isolates and the origin of polyclonality. Serial rectal isolates from ICU patients whose rectum was colonized on ≥5 sampling occasions were selected. From a total of 32 eligible colonized patients, isolates from a subgroup of 13 patients (a total of 108 isolates) showing different patterns of colonization as revealed by pulsed-field gel electrophoresis (PFGE) were studied. The isolates were analyzed by PFGE pulsotypes, sequence types (STs) by multi-locus sequence typing (MLST) and clonal complex (CC) by eBURST analysis. Serial isolates constituted a mixture of identical, related and unrelated pulsotypes. Analysis by STs and CCs were less discriminatory. The data suggest a combination of an initial colonizing isolate undergoing mutation as well as colonization by independent isolates. Further clarity on the origin of diversity should be better obtained by whole-genome sequencing.

Prevalence and antimicrobial susceptibility of enterotoxigenic extra-intestinal Bacteroides fragilis among 13-year collection of isolates in Kuwait

Background

Some strains of Bacteroides fragilis species are associated with diarrhea as a result of enterotoxin production (bft or fragilysin). Fragilysin is activated by C11 protease (fpn) and together with C10 protease (bfp) play a significant role in its invasiveness. The objectives of this study were to investigate the proportion of clinical isolates from extra-intestinal sources that are toxin producers and characterize the genes mediating toxin production. Clinical isolates submitted to our reference laboratory over the last 13 years were screened for toxin production using PCR technique. All stool isolates were excluded. The isolates were tested for their susceptibility to 8 antimicrobial agents by E test. Carbapenem resistance gene cfiA was detected by PCR.

Results

A total of 421 B. fragilis isolates were viable. Out of these, bft was detected in 210 (49.9%) isolates. Of the 210 bft-positive isolates, 171 (81.4%), 33 (15.7%) and 6 (2.8%) harbored bft-1, bft-2, and bft-3 genes, respectively. Twenty (9.5%) of the bft-positive strains originated from bloodstream infections. Twenty-five, 20 and 9 strains harbored bfp-1, bfp-2 and bfp-3 gene, respectively. Two, 3, 4 bfp isotypes were detected simultaneously in some of strains. The resistance rates against amoxicillin-clavulanic acid was 32%, clindamycin 62%, cefoxitin 26%, imipenem 11%, meropenem 17%, metronidazole 4%, piperacillin 61% and tigecycline 14%. A chromosomally located cfiA gene that encode metallo-β-lactamase was identified in only 34 isolates (16.2%).

Conclusions

The prevalence of enterotoxin-producing B. fragilis was high among the extra-intestinal isolates. Metronidazole was the most active agent against all isolates. There was no statistically significance difference between resistance rates among bft-positive and bft-negative isolates except for clindamycin.

535. Multicenter Study of the Prevalence of Rectal Colonization by Carbapenem-Resistant Enterobacteriaceae in Patients Admitted to the Intensive Care Units of 7 Major Hospitals in Kuwait

Background

The emergence of carbapenem-resistant Enterobacteriaceae (CRE) has become an important epidemiological change in infectious diseases in the last 10 years. The gut is an important reservoir for these isolates thereby creating an opportunity for dissemination in a hospital setting especially the intensive care units (ICUs). The objective of this study was to investigate the colonization rates of patients, by CRE, admitted to the ICUs of 7 teaching hospitals.

Methods

Rectal swabs were collected during July 2017 to November 2018 from all patients on the day of ICU admission and 1 week after in each hospital. The samples were screened by direct plating on MacConkey agar containing 10-μg meropenem. Bacterial species identification was performed using the VITEK-2 system. The minimum inhibitory concentrations (MICs) of 14 antibiotics were determined by using Etest. Genes encoding carbapenem resistance was detected by PCR and sequencing. Their clonal relationship was determined by pulsed-field gel electrophoresis (PFGE).

Results

A total of 2580 Enterobacteriaceae were isolated from all patients. Seventy-four (2.9%) were confirmed as CRE most of which were from patients in Adan (AH: 36.5%) and Mubarak (MH: 46%) hospitals. Sixty (81.1%) harbored one or more of the tested carbapenemases genes. Forty-six (62.2%) carried bla_OXA-181, 9 (12.2%) bla_OXA-48, one bla_KPC-2, while 14 (18.9%) carried 2 genes. Combinations of bla_KPC-2 and bla_OXA-181 genes were found in 5 (6.8%), bla_VIM-1 and bla_OXA-181 in 4 (5.4%), bla_NDM-5 and bla_OXA-181 in 3 (4.1%) and bla_NDM-1 and bla_OXA-181 in 2 (3.3%). The XbaI PFGE profile-based Dendrogram, at 85% similarity criterion, resolved 7 pulsotypes among isolates carrying bla_OXA-181 in AH and MH designated A, B, C, D, E, F, and G. Further analysis revealed that 7 subpulsotypes A1, A2, A5, A6, C1, C2, and E1 were from unit D in the medical ICU of MH and A3, A4, B1, B3, D1, D2, D3, D4, F1, F2, F3, G1, and G2 were from surgical/medical ICUs in AH. 100% similarity was demonstrated among 8 isolates from AH and 2 from MH.

Conclusion

The prevalence of rectal colonization by CRE in the ICU patients was lower than expected. Detection of bla_OXA-181 variety and bla_NDM-5 is new to the milieu of genes so far described in isolates from Kuwait.

Disclosures

All authors: No reported disclosures.

490. High Prevalence of Rectal Carriage of blaKPC –Mediated Carbapenem-Resistant Enterobacteriaceae Among Community Food Handlers in Kuwait

Background

Carbapenemases are diverse enzymes which inactivate the carbapenems. KPC-producing carbapenemase-producing Enterobacteriaceae have disseminated to many regions in the world, however, anecdotal reports of KPC-producing CPE in some GCC countries excluding Kuwait. In this study we report the first emergence of the KPC producing CPE isolated from healthy food handlers in our community.

Methods

Rectal swabs were collected from 405 food handlers. Isolates were identified by VITEK 2 and their susceptibility to 21 antibiotics performed by MIC determination using Etest. Genes encoding carbapenemase production were characterized by PCR and clonality of isolates was determined by MLST.

Results

A total of 36 CPE were isolated from 31 participants, of which 15 (41.7%) were Escherichia coli and 8 (22.2%) Klebsiella pneumoniae. All isolates were susceptible to amikacin and tigecycline but an alarmingly high percentage (38.9%) were non-susceptible to colistin. A very high proportion of the CPE harbored blaKPC (58.3%), followed by blaOXA-48 (25%), blaNDM (5.6%) and blaVIM (2.8%). Carbapenemases were co-produced with ESBLs in 30.6% of the isolates. Sequencing of the KPC revealed that KPC-18 represented 45%, KPC-2 36% and KPC-29 18%. Considerable genetic diversity among the isolates was identified by MLST assays demonstrating the emergence of new clones. Five diverse new CPE clones were detected from three Bangladeshi citizens and 2 Indians.

Conclusion

Our finding demonstrates a relatively high colonization rate (8.9%) of healthy food handlers by CPE of which KPC-producing CPE were predominant; this is an unusual finding in Kuwait representing the first of such findings in our country and GCC.

Disclosures

All authors: No reported disclosures.

Comparative in vitro activity of ceftaroline and comparator agents against nosocomial Gram-negative and Gram-positive clinically significant bacterial isolates from patients in a teaching hospital in Kuwait

The objective was to test the in vitro activities of ceftaroline and comparator agents against clinical isolates of Gram-negative and Gram-positive bacteria. Isolates were identified with VITEK II. Susceptibility testing was with E test. A total of 1264 isolates were tested. Compared to other cephalosporins, ceftaroline demonstrated excellent in vitro activities (MIC90, ≤0.5 mg/L) against Escherichia coli, Salmonella spp. and Haemophilus influenzae. When matched with the comparator cephalosporins, ceftaroline demonstrated the greatest activity against methicillin-susceptible Staphylococcus aureus (MSSA), with MIC90 of 0.25 mg/L. Ceftaroline's MIC90s against both community-associated methicillin-resistant S. aureus (MRSA) and hospital-acquired MRSA were 0.5 and 1 mg/L, respectively. Major discrepancies were noted between E test and disc diffusion tests for ceftaroline only against 16 Gram-negative and 16 Gram-positive isolates. Ceftaroline demonstrated an excellent in vitro activity against the majority of clinically significant Gram-negative and Gram-positive isolates obtained from proven cases of bacterial infections.

Overwhelming Streptococcus pyogenes sepsis in an elderly patient with septic arthritis

INTRODUCTION

The signs of Streptococcus pyogenes, group A streptococci (GAS) bacteremia are non-specific and patients can have wide presentations ranging from flu-like symptoms to life-threatening toxic-shock syndrome in just a few hours.

CASE PRESENTATION

We report a case of fulminant S. pyogenes sepsis in an elderly woman with septic arthritis and remarkable past medical history/risk factors. She was febrile, hypotensive and had a swollen and tender right knee. Multiple blood cultures and the synovial fluid culture yielded S. pyogenes. Despite adequate antimicrobial therapy with penicillin and clindamycin the patient succumbed to her infection within 4days of presentation in our hospital.

CONCLUSION

GAS remains penicillin sensitive most of the time but prompt appropriate antibiotic therapy is very crucial to survival.

High Prevalence of New Delhi Metallo-β-Lactamase-1 (NDM-1) Producers among Carbapenem-Resistant Enterobacteriaceae in Kuwait

The aim of the study was to determine the prevalence of New Delhi metallo-β lactamase-1 (NDM-1) producing Enterobacteriaceae in Kuwait over a one year period. Consecutive Enterobacteriaceae isolates with reduced susceptibility to carbapenems were collected from four government hospitals in Kuwait from January–December 2014. Their susceptibility to 18 antibiotics was performed by determining the minimum inhibitory concentration. Isolates resistant to carbapenems were tested by PCR for resistant genes. Finger printing of the positive isolates was done by DiversiLab^®. Clinical data of patients harboring NDM-1 positive isolates were analyzed. A total of 764 clinically significant Enterobacteriaceae isolates were studied. Of these, 61 (8%) were carbapenem-resistant. Twenty one out of these 61 (34.4%) were NDM-1-producers. All patients positive for NDM-1-carrying bacteria were hospitalized. About half were females (11/21 [52.3%]), average age was 53.3 years and the majority were Kuwaitis (14/21 [66.6%]). Six patients (28.5%) gave a history of travel or healthcare contact in an endemic area. Mortality rate was relatively high (28.6%). The predominant organism was Klebsiella pneumoniae (14 [66.6%]) followed by E. coli (4 [19%]). All NDM-1-positive isolates were resistant to meropenem, ertapenem, cefotaxime, cefoxitin and ampicillin, while 95.2% were resistant to imipenem, cefepime, and piperacillin-tazobactam. They were multidrug resistant including resistance to tigecycline, but 90% remained susceptible to colistin. About two-thirds of isolates (61.9%) co-produced-extended spectrum β-lactamases. During the study period, an outbreak of NDM-1 positive K. pneumoniae occurred in one hospital involving 3 patients confirmed by DiversiLab^® analysis. In conclusion, NDM-1-producing Enterobacteriaceae is a growing healthcare problem with increasing prevalence in Kuwait, especially in hospitalized patients, leaving few therapeutic options. A high prevalence of NDM-1 necessitates the implementation of strict infection control to prevent the spread of these organisms.

Characterization of Carbapenem-Resistant Enterobacteriaceae with High Rate of Autochthonous Transmission in the Arabian Peninsula

To establish the role of local transmission versus possible pathogen import due to previous foreign exposure in infections caused by carbapenem non-susceptible Enterobacteriaceae in the Arabian Peninsula, 200 independent isolates collected in 16 hospitals of Saudi Arabia, Kuwait, Oman and the United Arab Emirates were studied. All strains were multidrug resistant; 42.5% of them also qualified as extremely drug resistant. The frequency of various carbapenemases varied according to the participating countries, but in the collection, as a whole, bla_NDM-1 was the most frequently encountered carbapenemase gene (46.5%) followed by bla_OXA-48-like gene (32.5%). A comparatively high rate (8.9%) of multi-clonal strains carrying both bla_NDM and bla_OXA-48-like genes in the United Arab Emirates, representing the most resistant subgroup, was encountered. No KPC-expressing isolates were detected. Three major clones of bla_NDM-1 carrying Klebsiella pneumoniae of ST152 (n = 22, Saudi Arabia), ST14 (n = 7, United Arab Emirates) and ST147 types (n = 9, Oman) were identified, the latter two clones carrying similar, but not identical HI1b incompatibility type plasmids of >170kb. While from 78.6% of the cases with documented foreign hospitalization bla_NDM positive strains were isolated, these strains formed only 25.6% of all the isolates expressing this enzyme. In fact, 56.8% of the NDM, 75.7% of OXA-48-like and 90.9% of VIM positive strains were recovered from patients without documented foreign exposure, neither in the form of travel or prior hospitalization abroad, suggesting a high rate of autochthonous infections. This, considering the extensive links of these countries to the rest of the world, predicts that trends in the local epidemiology of carbapenem resistant strains may increasingly affect the spread of these pathogens on the global scale. These results call for improved surveillance of carbapenem resistant Enterobacteriaceae in the countries of the Arabian Peninsula.

Real-time comparative evaluation of bioMerieux VITEK MS versus Bruker Microflex MS, two matrix-assisted laser desorption-ionization time-of-flight mass spectrometry systems, for identification of clinically significant bacteria

Background

Matrix-assisted laser desorption-ionization time-of-flight mass spectrometry (MALDI-TOF MS) recently became available for the identification of bacteria in routine diagnostic laboratories. It is rapid and cost-effective and likely to replace phenotypic identification. This study was undertaken to compare two MALDI-TOF MS-based, Bruker Microflex MS (BMS) and VITEK MS (VMS) systems, for identification (ID) of clinically significant bacterial isolates. Clinically relevant broad diversity of bacterial isolates obtained during a 6-consecutive months of routine laboratory processing of clinical specimens were subjected to ID by the BMS and VMS in parallel with Vitek 2, a conventional phenotypic system (CPS). For the BMS, the isolates were tested in duplicates directly and after pretreatment. Identification was provided with accompanying scores according to manufacturers’ instructions. With VMS, single deposits of the same sets of isolates were tested in duplicates directly on MALDI-plate. Results were interpreted according to the manufacturer’s protocols. Discrepant results were resolved by 16S rRNA gene amplification and sequencing.

Results

A total of 806 pathogens comprising 507 Gram-negative bacilli (GNB), 16 Gram-negative cocci (GNC), 267 Gram-positive cocci (GPC), and 16 Gram-positive bacilli (GPB) were tested. BMS and VMS correctly identified isolates to genus and species levels (ID 97.3% and 93.2%, and 99.8% and 99.0%, respectively). Both systems as well as the CPS correctly identified the majority of the species in the family Enterobacteriaceae, Pseudomonas spp., and Acinetobacter baumannii. Turnaround time for identification by BMS and VMS was <20 min compared with 24-48 h by the CPS.

Conclusions

VMS performed slightly better than BMS with GPC ID, especially the Streptococcus spp. Some S. mitis isolates were identified as S. pneumoniae by BMS. BMS and VMS were rapid and proved to be consistently accurate for producing bacterial identification in a fraction of time it takes for identification by CPS.

Antimicrobial resistance among anaerobes isolated from clinical specimens in Kuwait hospitals: comparative analysis of 11-year data

Our objective was to compare the antimicrobial resistance trends among clinically relevant anaerobes against 9 different antibiotics over two periods, 2008-2012 and 2002-2007. Antimicrobial susceptibility testing was performed by determining the MICs using E test method. The interpretation of results was according to the breakpoints recommended by the Clinical Laboratory and Standard Institute (CLSI) and European Committee on Antimicrobial Susceptibility Testing (EUCAST). A total of 2240 clinically significant isolates were collected between 2008 and 2012 in four teaching hospitals in Kuwait. The commonest isolates were Bacteroides fragilis (40.4%), Prevotella bivia (18.6%), Peptostreptococcus spp. (13.8%) and Bacteroides ovatus (11.1%). According to CLSI and EUCAST breakpoints used for the 2008-2012 and 2002-2007 isolates, high resistance rates to amoxicillin-clavulanic acid, clindamycin, penicillin and piperacillin were noted among the Gram-negative isolates. They ranged between 0 and 0-62.1 and 62.1%, and 0 and 0-59.1 and 62.1%, respectively against clindamycin, 0 and 0-34.5 and 45.3%, and 0 and 0-45 and 57.5%, respectively against piperacillin and 0 and 0-24.2 and 24.2%, and 0 and 0-23.1 and 30.6%, respectively against amoxicillin-clavulanic acid. The mean interpretative results by both CLSI and EUCAST during the 2008-2012 and 2002-2007 periods showed that the B. fragilis isolates were highly resistant to penicillin (100 vs 100%), clindamycin (43.7 vs 44.2%), piperacillin (35.8 vs 42.7%) and amoxicillin-clavulanic acid (13.2 vs 14%), respectively. When compared with 2002-2007, the CLSI, but not EUCAST, demonstrated statistically significant decreased resistance to clindamycin (P < 0.03). However, both interpretative criteria showed demonstrable statistically significant decrease in resistance rates to imipenem (P < 0.00097 vs P < 0.00074), meropenem (P < 0.000006 vs P < 0.0407) and piperacillin (P < 0.000017 vs P < 0.0461). Our data shows that there is a need for periodic monitoring of the susceptibility testing for anaerobic bacteria in the face of increasing resistance rates as well as to guide in the empirical therapy of anaerobic infections.

Comparative evaluation of two matrix-assisted laser desorption/ionization time-of-flight mass spectrometry (MALDI-TOF MS) systems for the identification of clinically significant yeasts

OBJECTIVES

To prospectively evaluate the performance of two matrix-assisted laser desorption/ionization time-of-flight mass spectrometry systems (MALDI-TOF MS) for the identification of clinically significant yeast isolates compared to the VITEK 2 system.

METHODS

One hundred and eighty-eight consecutive yeast isolates were analyzed by Bruker Biotyper and VITEK MS. The results were compared with the conventional VITEK 2 yeast identification system. Discrepant results were resolved by direct sequencing of rDNA.

RESULTS

Accurate identification by VITEK 2, VITEK MS, and Bruker Biotyper MS was 94.1% (177/188), 93.0% (175/188), and 92.6% (174/188), respectively. Three isolates were not identified by VITEK MS, while nine Candida orthopsilosis were misidentified as Candida parapsilosis, as this species is not present in its database. Eleven isolates were not identified or were wrongly identified by Bruker Biotyper and although another 14 were correctly identified, the score was unreliable at <1.7.

CONCLUSION

The overall accuracy of rapid MALDI-TOF MS systems was essentially comparable to that of the conventional VITEK 2 yeast identification system. However, future expansion of the databases may further improve the outcome and accuracy of identification of yeast species.

In VitroActivity of Linezolid and Other Antibiotics Against Gram-Positive Bacteria from the Major Teaching Hospitals in Kuwait

Multidrug-resistant Gram-positive bacteria are an increasingly pressing problem in the clinic. Consequently, linezolid, a recently introduced oxazolidinone with Gram-positive activity, was tested in comparison with 10 other antibiotics against 8103 clinically significant Gram-positive cocci by Etest, disk diffusion and Vitek methods. Linezolid demonstrated excellent activities against all isolates. Vancomycin and teicoplanin demonstrated equally excellent activity against almost all isolates. The methicillin-resistant Staphylococcus aureus (MRSA) strains were all susceptible to the glycopeptides and linezolid, but resistant to erythromycin (96%), fusidic acid (91.5%), gentamicin (84%) and clindamycin (73%). Forty one and 39% of the Streptococcus pneumoniae isolates were resistant to penicillin (MIC >0.5 microg/ml) and erythromycin (MIC >1 microg/ml), respectively. S. agalactiae susceptibility was 9% and 10% resistant to clindamycin and erythromycin, respectively. In conclusion, all the Gram-positive isolates tested were susceptible to linezolid. With its oral bioavailability profiles, it obviously holds great promise. Our data should be a useful addition to the literature from the Middle East.

High Frequency of Isolation of Antibiotic-Resistant Oral Viridans Streptococci from Children in Kuwait

Antimicrobial resistance among the Viridans group of streptococci (VGS) has emerged as a hindrance to effective antibiotic therapy. Our objective was to evaluate the prevalence of antibiotic-resistant VGS in healthy children. Plaque samples were collected from tooth and tongue surfaces of 102 healthy subjects. Serially diluted samples were inoculated onto BHI agar plates and Mitis Salivarius Agar (MSA) plates and incubated as appropriate. Representative colonies were identified to species level by standard methods. Susceptibility of the VGS was performed by determining the minimum inhibitory concentrations (MICs) of 11 antibiotics using Etest. Of the 540 VGS isolates from both sites, 58% were from the tooth surfaces and 42% from the tongue. The most prevalent were S. salivarius (21.5%) and S. sanguis (16.3%). Imipenem and vancomycin had excellent activities. Resistance rates to trimethoprim, amoxicillin, piperacillin, erythromycin, cefuroxime and cephalothin, were 60.7, 40.8, 34.7, 32.6, 27.5 and 25.3%, respectively. Resistance rates to penicillin and clindamycin were 15.9% and 15.4%, respectively. The majority of the erythromycin-resistant isolates were from the tongue; 41% versus 29%. At the species level, 26% and 23% of S. salivarius and 23% and 14% of S. mutans from the tooth and tongue, respectively were resistant to penicillin. The data show species-related and site-related variations in the susceptibility pattern and an emerging high prevalence of antibiotic-resistant VGS. The difference in the susceptibilities between the species underscores the importance of accurate-identification and the need for surveillance of antimicrobial resistance among clinical isolates in our hospitals.

Point-surveillance of antibiotic resistance in Enterobacteriaceae isolates from patients in a Lagos Teaching Hospital, Nigeria

OBJECTIVES

This study was carried out to determine a point prevalence of drug resistance and extended-spectrum β-lactamase (ESBL) among members of the family Enterobacteriaceae.

METHODS

Consecutive clinically significant non-repetitive isolates obtained from both hospitalized patients and outpatients' samples were studied. The isolates were identified using VITEK 2 while susceptibility testing was performed against 16 antibiotics using the E-test strips. Phenotypic production of ESBL was detected by E-test ESBL method. Positive isolates were confirmed by PCR.

RESULTS

Of a total of 102 isolates studied, 43 (42.2%) were Escherichia coli and 32 (31.4%) Klebsiella pneumoniae. These isolates demonstrated remarkable high rates of resistance to the β-lactam antibiotics, except the carbapenems and piperacillin-tazobactam. Fifty-two (51%) were resistant to ≥ 3 classes of drugs and 29 (28.4%) to ≥ 5 drugs. Thirty-eight (37.3%) were ESBL producers. Of these, 21 (55.3%) were E. coli and 12 (31.6%) K. pneumoniae. Thus, the overall prevalence of ESBL-producing E. coli was 20.6% and K. pneumoniae 11.8%.

CONCLUSIONS

This study showed an alarmingly high prevalence of antibiotic resistance in invasive Enterobacteriaceae isolates and a high prevalence of ESBL producers in the study center. Antibiotic stewardship and other preventive strategies are recommended to reduce the high rate of resistant bacteria in this hospital.

High prevalence of VIM-4 and NDM-1 metallo-β-lactamase among carbapenem-resistant Enterobacteriaceae

The purpose of this study was to identify the mechanisms leading to carbapenem resistance among multidrug-resistant Enterobacteriaceae isolates recovered from hospitalized patients with nosocomial infections in Mubarak Al Kabeer Hospital, Kuwait. Fourteen carbapenem-resistant Enterobacteriaceae isolates were obtained from inpatients in different wards and intensive care units between April 2009 and February 2011. Antibiotic susceptibilities were determined using the E-test method. Genes encoding β-lactamases were characterized by specific PCR amplification, sequencing and conjugation assays. All isolates were identified as metallo-β-lactamase (MBL) producers using phenotypic and molecular methods. Eleven of the 14 isolates produced VIM-4 (six Klebsiella pneumoniae, three Escherichia coli, one Enterobacter cloacae and one Klebsiella oxytoca). Three K. pneumoniae isolates produced the MBL NDM-1 and co-produced the plasmid-encoded AmpC CMY-4. The VIM-4-producing isolates co-produced extended-spectrum β-lactamases including CTX-M-15 and some SHV derivatives. The VIM-4 gene was not transferable by conjugation studies of six selected strains. We demonstrated here the emergence of VIM-4- and NDM-1-producing isolates in the largest teaching hospital in Kuwait.

Comparison of two matrix-assisted laser desorption/ionization-time of flight (MALDI-TOF) mass spectrometry methods and API 20AN for identification of clinically relevant anaerobic bacteria

Matrix-assisted laser desorption/ionization-time of flight mass spectrometry (MALDI-TOF MS) is suitable for high-throughput and rapid microbial diagnosis at relatively low cost and can be considered an alternative to conventional biochemical and molecular identification systems in clinical microbiological laboratories, including anaerobe laboratories. Two commercially available MALDI-TOF MS systems, Bruker Microflex MS and bioMérieux VITEK MS, were evaluated for the identification of 274 isolates of clinically significant anaerobic bacteria recovered from routine cultures of clinical specimens in parallel with blinded comparison with conventional biochemical (API 20AN) or molecular methods. All were recovered cultures obtained from patients attending the Mubarak Al Kabir Hospital, Kuwait, during a 6 month period. Discrepant results after two attempts at direct colony testing had failed to provide acceptable MALDI-TOF identification were resolved by gold-standard 16S gene sequencing. The VITEK MS gave high-confidence identification of the 274 isolates, all of which were correctly identified. The Bruker Microflex MS system also gave high-confidence identification for 272 of the 274. After discrepancy testing, the Bruker MS results agreed with biochemical or molecular methods for 89.1 % of the isolates at species level and 10.2 % at genus level (0.72 % were misidentified). The level of agreement with the VITEK MS was 100 % at both species and genus level; no isolates were misidentified. Our data suggest that implementation of MALDI-TOF MS as a first step for identification will shorten the turnaround time and reduce the cost in the anaerobe laboratory.

A study of the microbiology of diabetic foot infections in a teaching hospital in Kuwait

The purpose of this study was to determine the microbiological profile of diabetic foot infections (DFIs) and assess the antibiotic susceptibility of the causative agents. Data were obtained from a retrospective analysis of DFI samples collected from June 2007 to July 2008. Specimens were cultured using optimal aerobic and anaerobic microbiological techniques, and antibiotic susceptibility testing was performed according to the methods recommended by the Clinical and Laboratory Standards Institute (CLSI). Extended-spectrum β-lactamase (ESBL) production was measured using the double disk synergy test and the ESBL Etest. A total of 440 patients were diagnosed with DFIs during this period, and a total of 777 pathogens were isolated from these patients with an average of 1.8 pathogens per lesion. We isolated more Gram-negative pathogens (51.2%) than Gram-positive pathogens (32.3%) or anaerobes (15.3%). Polymicrobial infection was identified in 75% of the patients. The predominant organisms isolated were members of the Enterobacteriaceae family (28.5%), Pseudomonas aeruginosa (17.4%), Staphylococcus aureus (11.8%), methicillin-resistant S. aureus (7.7%), anaerobic Gram-negative organisms (10.8%), and Enterococcus spp. (7%). Vancomycin was the most effective treatment for Gram-positive bacteria, and imipenem, piperacillin-tazobactam and amikacin were the most effective treatments for the Gram-negative bacteria. In conclusion, DFI is common among diabetic patients in Kuwait, and most of the cases evaluated in this study displayed polymicrobial etiology. The majority of isolates were multi-drug resistant. The data gathered in this study will be beneficial for future determinations of empirical therapy policies for the management of DFIs.

Emergence of tigecycline and colistin resistance in Acinetobacter species isolated from patients in Kuwait hospitals

The development of resistance is a compelling reason for reviewing administration of antibiotics. Recently, most Acinetobacter infections are caused by multidrug-resistant (MDR) strains which have necessitated the use of tigecycline or colistin. This study was undertaken to determine the susceptibility of Acinetobacter spp. to these and other drugs. A total of 250 Acinetobacter isolates were collected from the 8 government hospitals over a period of 6 months. Susceptibility to 18 antibiotics, including tigecycline and colistin, was investigated by determining their minimum inhibitory concentrations using E test. Of the 250 isolates, 13.6% and 12% were resistant to tigecycline and colistin. A total of 25.2% and 37.2% were resistant to imipenem and meropenem, respectively. Of the 250 isolates 88.4% were MDR. This relatively high prevalence of tigecycline and colistin-resistant isolates indicates an emerging therapeutic problem which may severely compromise the treatment of MDR Acinetobacter spp. infections in Kuwait.

A 4-year prospective study of septicemia in pediatric surgical patients at a tertiary care teaching hospital in Kuwait

BACKGROUND

Critically ill children are at high risk for developing nosocomial infections that contributes to death in 4% of all pediatric intensive care unit admissions. This prospective study was undertaken to determine the prevalence of septicemia in the pediatric surgery department of a large tertiary care teaching hospital in Kuwait and to evaluate the risk factors, the microbial etiology, and the antimicrobial susceptibility pattern of the isolated microorganisms.

METHODS

All patients admitted to the pediatric surgery department from January 2001 until December 2004 with the diagnosis of septicemia were included in the study, and the microbiologically proven cases were then analyzed. The patients' demographics and risk factors for sepsis were recorded. All positive blood cultures were subjected to identification and antimicrobial susceptibility testing by VITEK 2(bioMerieux, Marcy l'Etoile, France).

RESULTS

Of 3408 patients suspected to have septicemia, 78 (2.3%) patients developed microbiologically documented septicemias, 26% of those were low-birth weight patients, and 82% were patients with congenital anomalies; 87% of those needed surgical intervention. More than 50% were admitted to the intensive care unit, and 80.5% needed ventilatory support. Fifty-seven percent had early onset septicemia. Gram-positive and gram-negative bacteria accounted for 54% and 39% of the septicemia cases, respectively, whereas Candida spp was responsible for 7%. More than 50% of the staphylococci were resistant to cloxacillin, and all gram-positives were uniformly susceptible to glycopeptides and linezolid. Gram-negative bacteria showed variable resistance to cephalosporins (65%), piperacillin/tazobactam (29%), and carbapenems (11%). The attributable mortality rate for these septic episodes was 19% mainly because of gram-negative bacteria and Candida.

CONCLUSION

The main etiologic agents of neonatal septicemia were coagulase-negative Staphylococcus, Pseudomonas aeruginosa, and members of the family Enterobacteriaceae. Empirical therapy with piperacillin/tazobactam or carbapenems for gram-negative septicemia and glycopeptides for gram-positive septicemia was effective.

A study of the microbiology of breast abscess in a teaching hospital in Kuwait

OBJECTIVES

To determine the microbiological profile of breast abscess and assess the antibiotic susceptibility of the causative agents.

MATERIALS AND METHODS

Data obtained from cases of breast abscess over a period of 3.5 years, June 2006 to December 2009, were retrospectively analyzed. Specimens were cultured using optimal aerobic and anaerobic microbiological techniques. The antibiotic susceptibility test was carried out using the methods recommended by the Clinical and Laboratory Standards Institute. One specimen per patient was analyzed.

RESULTS

Of the 114 patients, 107 (93.8%) non-lactating and 7 (6.1%) lactating women were diagnosed with breast abscess during this period. Of the 114 specimens, 83 (73%) yielded bacterial growth. Of these, 115 pathogens were isolated with an average of 1.4 pathogens per abscess. Eighteen (22%) of the 83 specimens yielded mixed bacterial growth. There were more Gram-positive pathogens (60, 52%) than anaerobes (32, 28%) and Gram-negative pathogens (22, 19%). The predominant organisms were methicillin-susceptible Staphylococcus aureus (37, 32%), methicillin-resistant S. aureus (MRSA; 11, 10%), Bacteroides spp. (16, 14%), anaerobic streptococci (14, 12%) and Pseudomonas aeruginosa (9, 8%). Of the 48 S. aureus, MRSA accounted for 11 (23%). All MRSA isolates were susceptible to trimethoprim-sulfamethoxazole and vancomycin.

CONCLUSION

S. aureus was the most common pathogenic organism isolated in breast abscesses at Al-Amiri Hospital, Kuwait, of which 23% were MRSA. Nearly a third of the cases were caused by anaerobes, particularly B. fragilis. The data present a basis for the formation of empirical antimicrobial therapeutic policy in the management of breast abscess.

Sequence analysis of bla(CTX-M) genes carried by clinically significant Escherichia coli isolates in Kuwait hospitals

OBJECTIVE

To investigate the extent, distribution and sequence analysis of bla(CTX-M) genes carried by Escherichia coli isolated from patients admitted to all government hospitals in Kuwait.

METHODS

Extended-spectrum β-lactamase (ESBL)-producing E. coli isolates were collected from the 8 major hospitals in Kuwait. CTX-M ESBLs were analyzed by PCR and sequenced. Clonality of the positive isolates was determined for genetic relatedness using pulsed-field gel electrophoresis (PFGE) with XbaI digestion of the genomic DNA.

RESULTS

Of the 136 ESBL-positive isolates, 106 (77.9%) harbored bla(CTX-M) genes. Among these, bla(CTX-M-15) was the most frequent with a prevalence rate of 84.1%, followed by bla(CTX-M-14) (6.8%), bla(CTX-M-14b) (5.7%) and bla(TOHO-1) (3.4%). Ninety-three (87.7%) were isolated from Kuwaiti (35.9%), Egyptian (31.1%) and Indian (20.8%) nationals; the majority of isolates positive for bla(CTX-M-15) were mainly from these 3 nationalities. PFGE analysis did not demonstrate any clustering of positive isolates in any particular hospital.

CONCLUSION

This study confirms an explosive emergence of CTX-M-15 β-lactamase among E. coli isolates in Kuwait and shows that the strains were clonally heterogeneous with no evidence of inter- or intra-hospital spread. Thus Kuwait may represent an important source of CTX-M-15-positive E. coli.

Analysis of prevalence, risk factors and molecular epidemiology of Clostridium difficile infection in Kuwait over a 3-year period

We conducted a prospective study to evaluate the prevalence and epidemiology of CDI in Kuwait government hospitals over a 3-year period, January 2003 to December 2005, to determine the ribotypes responsible for CDI and to estimate the prevalence of ribotype 027. We also conducted a case-control study to identify the risk factors in our patient population. A total of 697 stool samples from patients with suspected CDI were obtained and sent to Anaerobe Reference Laboratory, Faculty of Medicine, Kuwait University for Clostridium difficile toxin detection, culture and PCR ribotyping. During the period, 73 (10.5%) out of 697 patients met the case definition of CDI. Of these, 56 (76.7%) were hospital-acquired and 17 (23.3%) were from outpatient clinics. Thus, the prevalence of hospital-acquired CDI amongst patients with diarrhoea was 8% over the study period; the prevalence in 2003, 2004 and 2005 was 9.7%, 7.8% and 7.2%, respectively. Our data showed that 42.9% of the CDI patients were above 60 years, of which >79% were aged 71 years and above. Patients with CDI were more likely than the controls to have been exposed to immunosuppressive drugs and feeding via nasogastric tube. The most common ribotypes isolated during this study were 002, 001, 126 and 140 and they represent 55.1% of all isolates. PCR ribotype 027 was not isolated.

Correlation of multidrug resistance, toxinotypes and PCR ribotypes in Clostridium difficile isolates from Kuwait

Clostridium difficile is a common cause of nosocomial diarrhea. its role in community-acquired diarrhea is also becoming an important public health concern. Hardly any studies have correlated strain ribotypes, toxinotypes and multidrug resistant (MDR) profiles. To investigate these characteristics, 65 C. difficile isolates obtained from stool samples of patients whose cultures were negative on admission but became positive after 48 h of admission to the ICUs of our hospitals were studied to determine the prevalent ribotypes, toxinotypes and their relationship with the MDR profiles using ELISA/cytotoxicity assays, PCR and Etest methods. The toxin-producing strains were toxinotyped by the PCR-RFLP technique. Of the 65 isolates, 42 (64.6%) were toxigenic (T). The isolates were of diverse ribotypes but types 097, 078, 056 and 039 (NT) were predominant. thirty (71.4%) of 42 T and 13 (56.5%) of 23 NT strains were multiresistant to 3 or more antibiotics. Only 3 toxinotypes (0, "V-like" and XII) were encountered. Of the 42 t strains, 30 (71.4%) were of toxinotype 0, and 12 belonged to variant toxinotypes: 4 (9.4%) to toxinotype XII and 8 (19%) to "V-like" toxinotype in which amplified B1 PCR fragments was amplified as expected for toxinotype V but the A3 PCR fragment could not be amplified. The 43 mDR strains were assigned to 3 arbitrary resistance groups; groups 1, 11 and III. the most prevalent isolates (37; 86.1%) were in group II. Of the predominant T ribotypes (097, 078 and 056), c. 62% clustered in group II. Although the number of strains toxinotyped was small, ribotyping and toxinotyping correlated well with the published literature, except for 078 with a novel "V-like" toxinotype. Antibiogram was not as clear-cut.

A case of community-onset meningitis caused by hospital methicillin-resistant Staphylococcus aureus successfully treated with linezolid and rifampicin

OBJECTIVE

To report a relatively rare presentation of methicillin-resistant Staphylococcus aureus (MRSA) meningitis in a previously healthy boy in Kuwait.

CLINICAL PRESENTATION AND INTERVENTION

A 14-year-old boy presented with a 2 weeks' history of headache and fever with increasing severity. He developed photophobia and double vision 2 days prior to his hospital visit and received ceftriaxone for 6 days prior to admission to the hospital. There was no history of head trauma or neurosurgical operation. Lumbar puncture revealed a slightly turbid cerebrospinal fluid with pleocytosis and greatly reduced glucose, elevated protein level and on culture grew MRSA. Staphylococcal chromosome cassette mec (SCCmec) typing revealed that it belonged to SCCmec type III and sequence type 238 (ST238-SCCmec-III). Polymerase chain reaction screening for the presence of Panton-Valentine leukocidin (PVL) genes yielded a negative result; all these findings were consistent with hospital-acquired MRSA. He was treated with intravenous linezolid and rifampicin for 2 weeks, made good response and was discharged home fully recovered and well.

CONCLUSION

Hospital MRSA should be considered in the differential diagnosis of the causative agents of community-onset meningitis in healthy patients even without predisposing factor.

Etiology and antibiotic susceptibility patterns of community- and hospital-acquired urinary tract infections in a general hospital in Kuwait

OBJECTIVE

Our purpose was to determine the bacterial profile and prevalence of antibiotic resistance patterns of uropathogens, as well as evaluate the problem with extended-spectrum β-lactamase (ESBL) producing isolates, causing urinary tract infections (UTIs) in Al-Amiri Hospital, Kuwait, over a 3-year period.

MATERIALS AND METHODS

Isolates (56,505) from symptomatic UTI cases from January 2005 to December 2007 were identified by conventional methods and the VITEK identification card system. Antimicrobial susceptibility testing was performed by disk diffusion method for Gram-positive organisms and an automated VITEK 2 machine for Gram-negative organisms. ESBL production by the Enterobacteriaceae was detected by the double-disk diffusion method and VITEK-2 system.

RESULTS

Significant bacteriuria was detected in 15,064 (26.6%) of the 56,505 urine samples. Escherichia coli accounted for 4,876 (54.9%) from community-acquired UTI (CA-UTI) and 2,253 (36.4%) from hospital-acquired UTI (HA-UTI), followed by Streptococcus agalactiae (1,129, 12.7%) and Klebsiella pneumoniae (962, 10.8%) from CA-UTI cases. Candida spp. (973, 15.7%) and K. pneumoniae (747, 12.1%) were the second and third most prevalent isolates, respectively, in HA-UTI. High resistance rates were observed among the Enterobacteriaceae against ampicillin, cephalothin, ciprofloxacin, piperacillin and trimethoprim-sulfamethoxazole. About 855 (12%) and 291 (17%) of E. coli and K. pneumoniae, respectively, were resistant to ≥4 antibiotics. The prevalence of ESBL-producing E. coli and K. pneumoniae in CA-UTI was 12 and 17% and in HA-UTI 26 and 28%, respectively.

CONCLUSION

A high percentage of the uropathogens causing UTI in the Al-Amiri Hospital setting was highly resistant to the first- and second-line antibiotics for the therapy of UTI. ESBL-producing bacteria are highly prevalent in our hospital.

Comparative in vitro activity of tigecycline and nine other antibiotics against gram-negative bacterial isolates, including ESBL-producing strains

The enterobacteriaceae, especially Escherichia coli and Klebsiella spp., as well as Acinetobacter spp., are important agents of nosocomial infections in hospitalized patients. A total of 460 Gram-negative bacteria (GNb), were investigated for their susceptibility to tigecycline and 9 other antibiotics by the etest. ESBL production was inferred from ESBL etest phenotypes. All the GNb, including the ESBL-producers, were susceptible to tigecycline with MIC(90 )ranges of 0.25 to 2 microg/ml. Imipenem and meropenem were very active against ESBL and non-ESBL producers; mean MIC(90)s of 0.19 and 0.09 microg/ml and 0.05 microg/ml and 0.02 microg/ml, respectively. The MIC(90)s of imipenem and meropenem for the Acinetobacter spp. were 16 and >32 microg/ml, respectively with resistance rates of 64.3 and 66.1%. ESBL production was detected in 62% and 82.1% of the E. coli and K. pneumoniae isolates, respectively. Resistance to ciprofloxacin was higher among the ESBL-producing strains of E. coli and K. pneumoniae than the non-ESBL producers. Comparatively, tigecycline had excellent in vitro activities against ESBL-producing enterobacteriaceae and demonstrated superior activity against Acinetobacter spp. Increasing ESBL production and resistance to ciprofloxacin and gentamicin in enterobacteriaceae require careful selection of empirical therapy. Tigecycline holds promise as an alternative choice of therapy for infections caused by ESBL-producing isolates and multi-drug resistant Acinetobacter spp.

Role of tigecycline in the control of a carbapenem-resistant Acinetobacter baumannii outbreak in an intensive care unit

The incidence of Acinetobacter baumannii infection has greatly increased over recent decades with infections occurring more in critically ill hospitalised patients. Hospital outbreaks of multiple antibiotic-resistant strains are posing an increasing threat to public health. Three different outbreaks of multidrug-resistant A. baumannii (MRAB) infections involving 24 patients, aged 16-75 years occurred in the intensive care unit in the course of one year. The isolates were cultured from clinical samples and identified using automated Vitek II ID system and the API 20NE system. Susceptibility testing was done by the E-test method. Molecular typing of the isolates was determined by pulsed-field electrophoresis. Screening of both patients and the environment was carried out. The acquisition time, i.e. the time of admission to time of acquiring infection, ranged from 3 to 31 days. All isolates were multiply resistant (MRAB), including resistance to carbapenems (MRAB-C) in the majority of cases but susceptible to tigecycline, with a minimum inhibitory concentration (MIC(90)) of 2 microg/mL. The overall mortality rate was 16.7%. Time-to-clearance of the MRAB-C was 8.3 days in the first outbreak, when tigecycline was not used, and 2.8 and 3.1 days during the second and third outbreaks, respectively, when tigecycline was used, and all but one patient survived. Environmental screening revealed gross contamination of many surfaces and equipment within the unit. The outbreak strains belonged to two distinct clones (D and E) whereas the 14 environmental strains belonged to three distinct groups (A-C). The outbreak of infections treated with tigecycline was successfully eliminated in conjunction with an aggressive infection control strategy.

Diarrhoeagenic Escherichia coli are not a significant cause of diarrhoea in hospitalised children in Kuwait

Background

The importance of diarrhoeagenic Escherichia coli (DEC) infections in the Arabian Gulf including Kuwait is not known. The prevalence of DEC (enterotoxigenic [ETEC], enteropathogenic [EPEC], enteroinvasive [EIEC], enterohemorrhagic [EHEC] and enteroaggregative [EAEC]) was studied in 537 children ≤ 5 years old hospitalised with acute diarrhoea and 113 matched controls from two hospitals during 2005–07 by PCR assays using E. coli colony pools.

Results

The prevalence of DEC varied from 0.75% for EHEC to 8.4% for EPEC (mostly atypical variety) in diarrhoeal children with no significant differences compared to that in control children (P values 0.15 to 1.00). Twenty-seven EPEC isolates studied mostly belonged to non-traditional serotypes and possessed β and θ intimin subtypes. A total of 54 DEC isolates from diarrhoeal children and 4 from controls studied for antimicrobial susceptibility showed resistance for older antimicrobials, ampicillin (0 to 100%), tetracycline (33 to 100%) and trimethoprim (22.2 to 100%); 43.1% of the isolates were multidrug-resistant (resistant to 3 or more agents). Six (10.4%) DEC isolates produced extended spectrum β-lactamases and possessed genetic elements (bla_CTX-M, bla_TEM and ISEcp1) associated with them.

Conclusion

We speculate that the lack of significant association of DEC with diarrhoea in children in Kuwait compared to countries surrounding the Arabian Gulf Region may be attributable to high environmental and food hygiene due to high disposable income in Kuwait.

Mycobacterium tuberculosis breast infection mimicking pyogenic abscesses in Kuwait

OBJECTIVE

To present 2 cases of primary breast abscesses caused by Mycobacterium tuberculosis mimicking pyogenic abscesses in healthy young females.

CLINICAL PRESENTATION AND INTERVENTION

Two young non-lactating Indonesian and Indian women, aged 27 and 29 years old, respectively, presented with breast abscesses caused by M.tuberculosis. The breasts presented as huge, swollen, hot, tender masses with a discharge at the subareolar site. Surgical drainage revealed deep abscess with copious amount of pus, samples of which were positive for acid-fast bacilli (AFB) and later confirmed as M.tuberculosis by positive cultures in Becton Dickinson BBL Migit and BACTEC 12B media. The initial therapies with clindamycin were changed to 4 anti-tuberculous drugs as soon as the smears showed the presence of AFB. The patients were discharged a week later, but both were lost to follow-up.

CONCLUSION

Mammary tuberculosis should be considered in the differential diagnosis of breast lesion, especially in patients from endemic areas.