Monika Pobiega

Molecular characterization and drug resistance of Escherichia coli strains isolated from urine from long-term care facility residents in Cracow, Poland.

Background The aim of this study was to assess the prevalence of multidrug-resistant Escherichia coli and extended-spectrum β-lactamases (ESBL) pathogens isolated from asymptomatic bacteriuria and urinary tract infections (UTIs), and the relationship between the phylogeny, antimicrobial resistance, and virulence among isolates in residents of 3 long-term care facilities (LTCF) in Krakow, Poland. Material/Methods This was point prevalence study and prospective infection control in a group of 217 people. Urine samples were examined with standard microbiological methods and screened for the presence of blaCTX-M, blaSHV, and blaTEM. E. coli isolates were screened for 6 common virulence factors (VFs) and classified according to the rapid phylogenetic grouping technique. Results Among all the strains tested, 14 isolates (13.9%) expressed ESBL activity. A significant proportion of isolates were resistant to ciprofloxacin (32.7%, n=33). Resistance to trimethoprim/sulfamethoxazole was identified among 45 isolates (44.5%). Independent risk factors for the presence of an ESBL-producing strain were: UTI, urinary and/or fecal incontinence, bedridden, and low values of the Barthel and Katz Indexes. Gene sequencing identified 8 blaCTX-M-15, 1 blaCTX-M-3, 9 blaTEM-1, and 1 blaSHV-12. Among E. coli, no relationship between number of VF genes and phylogeny was found. The most prevalent virulence factor was fimH (82.1%). Conclusions The findings of this study emphasize the need for further research on the epidemiology of multi-drug resistant organisms (MDRO) and ESBL in LTCF, including transmission patterns, rates of infection, and factors associated with infections. It may be necessary to extend the requirements and precautions to MDRO and ESBL-producers.

Age and other risk factors of pneumonia among residents of Polish long-term care facilities.

BACKGROUND Pneumonia is one of the leading causes of morbidity and mortality in the elderly population. Nursing home-acquired pneumonia (NHAP) is probably the largest health problem in long-term care facilities (LTCFs). It is the second most common infection in LTCFs and frequently requires hospitalization. The aim of this study was to investigate the incidence rate of NHAP among LTCF residents, its microbial etiology, and the frequency of multidrug-resistant microorganisms. Risk factors for NHAP were analyzed. METHODS This was a prospective study conducted on a group of 217 elderly subjects aged ≥65 years, recruited from the inhabitants of LTCFs, with disabled elderly individuals living in the community serving as controls. Continuous surveillance was carried out from December 1, 2009 to November 30, 2010. RESULTS The incidence rate of NHAP in the observed population of Polish residents was 0.6/1000 resident-days. Vulnerability to NHAP was due to the poor general condition of residents, expressed by low Barthel index values (relative risk (RR) 1.6), the activities of daily living (ADL) score (RR 1.7), the Katz scale (RR 1.2), and limited physical activity (RR 1.6). Also significant were malnutrition (RR 2.3), the use of a bladder catheter (RR 1.3), dysphagia (RR 1.7), tracheotomy tube (RR 3.1), and gastric feeding tube (RR 3.5). Enterobacteriaceae were the predominant etiological agents of NHAP (56.3%). CONCLUSIONS The significance of risk factors for NHAP among residents in LTCFs was confirmed. Unfortunately, we also found that a lack of proper supervision with regard to the microbiology of infections is characteristic of Polish health care and LTCFs. There is an opportunity to improve the medical care of patients with severe disabilities, limit the rise in antimicrobial resistance and the need for hospitalization, and improve the prognosis.

Molecular epidemiology, plasmid analysis, virulence, and resistance of Escherichia coli isolated from neonatal intensive care units in Poland

We investigated the set of Escherichia coli isolates originating from newborns in relation to resistance, virulence factors (VFs), phylogenetic groups, plasmid replicon typing, and genotypes. The most isolates were clustered in ECOR group B2. Extended-spectrum beta-lactamase phenotype was found in 27.7% of isolates. The ST131 clone was detected among 33 strains, 12 of which carried the CTX-M-15 gene. Most VFs were detected among ST131 isolates and in the B2 group. IbeA gene was found more frequently in the blood isolates, while the iha gene, in the urine isolates. The 3 most prevalent replicon types were IncFIB, IncF, and IncFIA.

Molecular Epidemiology and Drug Resistance of Acinetobacter baumannii Isolated from Hospitals in Southern Poland: ICU as a Risk Factor for XDR Strains

The objectives of the present study were to investigate the carbapenemase and metallo-beta-lactamase genes of Acinetobacter baumannii clinical isolates by polymerase chain reaction (PCR) and real time PCR and to determine the molecular epidemiology of the strains using the DiversiLab tool. From these data, correlations between drug resistance, resistance genes, and epidemiological clones may be revealed. The study was conducted on 125 A. baumannii collected over the 2013 year. The majority of the isolates from both intensive care unit (ICU) and non-ICU cases originated from pneumonia infections (79.2%), isolates from blood infections accounted for 17.6% and 3.2% were from meningitis infections. In the ICU cases compared with the non-ICU cases, bloodstream infections were more frequently diagnosed (19.2% vs. 11.5%). Sixty percent of A. baumannii strains were resistant to all the antimicrobials tested with the exception of colistin. All strains were susceptible to colistin and polymyxin B. Extensively drug-resistant (XDR) strains accounted for 80.8% of the isolates tested and these XDR strains were more frequently isolated from ICU cases than from non-ICU cases (93.9% vs. 30.8%). Among the 101 isolates of A. baumannii exhibiting the XDR pattern of resistance, 80 possessed the blaOXA-24 gene and 29 had the blaOXA-23 gene. Only two isolates possessed the blaVIM gene. The presence of the ISAba1element was confirmed among 10 strains from patients hospitalized in the ICU. Using repetitive extragenic palindromic sequence PCR (DiversiLab typing), six clones and 12 unique strains were identified, of which two clones dominated. Most isolates belonging to clone 1 (66.7%) and clone 2 (85.5%) were susceptible only to colistin. In summary, it is clear from our findings and those of other studies that carbapenem resistance among A. baumannii strains presents a serious clinical problem worldwide. Furthermore, the presence of XDR international clone II in ICUs poses a potential risk for future outbreaks of A. baumannii infection and controlling A. baumannii infections in hospitals presents a serious challenge.

Epidemiology, antibiotic consumption and molecular characterisation of Staphylococcus aureus infections – data from the Polish Neonatology Surveillance Network, 2009–2012

BackgroundOur aim was to determine and characterize S. aureus (SA) isolated from infections in newborns for antibiotic resistance, virulence factors, genotypes, epidemiology and antibiotic consumption.MethodsProspective surveillance of infections was conducted. Data about antibiotic treatment were analyzed. Antimicrobial susceptibility was assessed. PCR amplification was used to detect resistance and virulence genes. Typing methods such as PFGE, spa-typing and SCCmec were used.ResultsSA was found to be associated with 6.5% of infections. Methicillin-Resistant Staphylococcus aureus accounted for 32.8% of SA-infections. An incidence of MRSA-infections was 1.1/1000 newborns. MRSA-infections were diagnosed significantly earlier than MSSA-infections in these newborns (14th day vs. 23rd day (p = 0.0194)). MRSA-infections increased the risk of newborn’s death. Antibiotic consumption in both group was similar, but a high level of glycopeptides-usage for MSSA infections was observed.In the MRSA group, more strains were resistant to erythromycin, clindamycin, gentamicin and amikacin than in the MSSA group. Hla gene was present in 93.9% of strains, and seg and sei in 65.3% of strains, respectively. One dominant clone was found among the 14 MRSA isolates. Fifteen strains belonging to SCCmec type IV were spa-t015 and one strain belonging to SCCmec type V was spa-t011.ConclusionsResults obtained in the study point at specific epidemiological situation in Polish NICU (more detailed studies are recommended).High usage of glycopeptides in the MSSA infections treatment indicates the necessity of antimicrobial stewardship improvement and introducing molecular screening for early identification of infections.

Molecular characterization of carbapenem-resistant Pseudomonas aeruginosa strains isolated from patients with urinary tract infections in Southern Poland

Due to the clinical threat posed by multidrug-resistant (MDR) Pseudomonas aeruginosa and importance of virulence factors produced in infection, 21 carbapenem-resistant P. aeruginosa were analyzed. 42.8% metallo-beta-lactamases-positive strains were identified. 85.7% of strains were meropenem resistant. 14.2% of strains were MDR; 38%, extensively drug-resistant (XDR). ExoY was present in all strains; exoT, in 95.2%; exoS, in 90.5%; exoU, in 47.6%. Eight XDR strains were typed using multilocus sequence typing: 4 as ST235, 2 as ST260, 2 as ST654 and ST234. MDR P. aeruginosa were isolated from hospitalized patients and among those from the community. Our study demonstrates the serious clinical issues posed by MDR P. aeruginosa and underscores the need for new treatment.

The general status of patients and limited physical activity as risk factors of Methicillin-resistant Staphylococcus aureus occurrence in long-term care facilities residents in Krakow, Poland.

BackgroundThe aim of this study was to investigate the epidemiology and resistance of methicillin-resistant Staphylococcus aureus (MRSA) isolates from long-term care facilities (LTCF) residents and to analyze the potential risk factors for MRSA occurrence, defined as MRSA colonization and/or infection.MethodsPoint prevalence (PPS) and prospective incidence continuous study (CS) was carried out on a group of 193 residents in 2009-2010.ResultsOverall MRSA occurred (with or without infection) among 17.6% of residents. There was 16 cases of infections with SA aetiology, of which 10 (58.8%) were caused by MRSA. The MRSA prevalence in PPS was 12.9%, in CS infection incidence rate was 5.2%. Factors associated with MRSA occurrence were: general status of patients, limited physical activity, wound infections (odds ratio, OR 4.6), ulcers in PPS (OR 2.1), diabetes (OR 1.6), urinary catheterization (OR 1.6) and stool incontinence (OR 1.2).ConclusionsOur data indicate a need for screening of MRSA before hospitalization or transfer to rehabilitation centres, especially in a group of residents with limitations in physical activity – i.e. with the highest risk of MRSA. Results also suggest the need for contact precautions in patients with high risk of MRSA occurrence, only. Focus on the high-risk population might be a solution for the cost-effective surveillance.

Urinary tract infections caused by Pseudomonas aeruginosa among children in Southern Poland: Virulence factors and antibiotic resistance.

OBJECTIVE The aim of this study was to analyze antibiotic resistance and virulence patterns in Pseudomonas aeruginosa (PAR) isolates from urinary tract infections among children in Southern Poland. MATERIALS AND METHODS This study comprised consecutive, non-repetitive PAR isolates sent from two collaborative laboratories. The study group consisted of children aged up to 17 years from Southern Poland with culture-proven PAR UTIs. Relevant information about patients with UTIs, such as age, sex, and type of infection (polymicrobial or monomicrobial), was collected. Isolates were screened for major virulence factors found in uropathogenic PAR strains. Multidrug-resistant (MDR) strains were defined as strains not susceptible to one antimicrobial in at least three different antimicrobial classes. Extensively drug resistant (XDR) strains were defined as strains susceptible to no more than two antimicrobial classes. RESULTS The total prevalence of PAR UTIs was 2.1%, and in children <5 years of age it was 3.0%. A total of 26 isolates was tested: 21 from outpatients and five from inpatients. Most infections (80.8%) occurred in children ≤ 4 years of age. The most prevalent virulence gene was exoY (96.2%). The prevalence of other effector proteins was 88.5% for exoT, 92.3% for exoS, and 19.2% for exoU. The gene for LasB was present in 80.8% of isolates; the gene for AprA in 61.5%; the gene for PilA in 19.2%; and the gene for PilB was not detected. The PAR isolates were generally susceptible to beta-lactam and aminoglycoside antimicrobials. All isolates were also susceptible to colistin. A large proportion of isolates were resistant to carbapenems and fluoroquinolones (Fig. 1). No significant differences were found in antimicrobial resistance between males and females or inpatients and outpatients (p > 0.05 for all tested antimicrobials), or in antimicrobial resistance between younger (≤ 5 years old, n = 21) and older (> 5 years old, n = 5) children (p > 0.05 for all tested antimicrobials). Two isolates were classified as XDR and none as MDR. The EDTA test yielded one MBL-positive isolate (3.8%), from a 17-year-old patient in home care. No isolates with genes for the KPC, IMP, or VIM were identified. CONCLUSION As data on UTIs in children with Pseudomonas etiology are scarce, this paper provides useful information for clinicians and allows for comparison between Poland and other countries. Our findings have important implications for clinicians treating UTIs empirically, because the success of empiric treatment is based on knowledge of pathogen antimicrobial susceptibility patterns.

Multi-locus sequence typing (MLST) of non-fermentative Gram-negative bacilli isolated from bloodstream infections in southern Poland

Non-fermentative Gram-negative bacilli are now one of the most important causes of severe infections in Polish hospitals. Acinetobacter species are serious concern because of the high prevalence of multi-drug resistance among strains. Resistance profiles for 53 Gram-negative non-fermentative blood isolates were done. MLST was carried out using 44 strains representing the most commonly isolated species: A. baumannii, P. aeruginosa, and S. maltophilia. MLST revealed that all 22 A. baumannii belonged to sequence type (ST) 2. The P. aeruginosa isolates belonged to 10 different STs. Four S. maltophilia isolates matched STs present in the database (ST4, ST15, ST116, ST142), seven isolates showing novel sequence types. Among P. aeruginosa and S. maltophilia PFGE confirmed the genetical variety of strains.