Virulence analysis and antibiotic resistance of Klebsiella pneumoniae isolates from hospitalised patients in Poland.

Klebsiella pneumoniae (KP) is a nosocomial pathogen causing difficult-to-treat infections. The presence of virulence genes and antibiotic resistance of 109 KP isolates from hospitalized patients were investigated. Among them, 68.8% were multi-drug resistant (MDR) and 59.6% produced extended-spectrum beta-lactamases (ESBLs). Metallo-ß-lactamases (MBLs) were produced by 22% of isolates (mainly from anus), including 16.5% of isolates producing New Delhi metallo-ß-lactamase (NDM-1). The genes encoding adhesins (fimH-91.7%, mrkD-96.3%), enterobactin (entB-100%) and yersiniabactin (irp-1-88%) were frequently identified. The genes encoding salmochelin (iroD-9.2%, iroN-7.3%) and colibactin (clbA, clbB-0.9%) were identified rarely. Iron acquisition system-related kfu gene and wcaG gene involved in capsule production were identified in 6.4% and 11% of isolates, respectively. The rmpA gene associated with hypermucoviscosity was present in 6.4% of isolates. In 19.2% of isolates magA gene was detected, specific for K1 capsule serotype, while 22.9% of isolates showed K2 capsule serotype. The rmpA, iroD or iroN genes being diagnostic biomarkers for hypervirulent KP (hvKP) were detected in 16.5% of isolates. We found that 55.5% of hvKP were MDR and produced ESBLs, thus hospital KP isolates pose a serious threat to the healthcare system.

Antibiotic Resistance of Uropathogens Isolated from Patients Hospitalized in District Hospital in Central Poland in 2020.

The aim of this study was to determine antibiotic resistance patterns and the prevalence of uropathogenes causing urinary tract infections (UTIs) in patients hospitalized in January-June 2020 in central Poland. Antimicrobial susceptibility testing was performed using the disk-diffusion method. Escherichia coli (52.2%), Klebsiella pneumoniae (13.7%), Enterococcus faecalis (9.3%), E. faecium (6.2%), and Proteus mirabilis (4,3%) were most commonly isolated from urine samples. E. coli was significantly more frequent in women (58.6%) (p = 0.0089) and in the age group 0-18, while K. pneumoniae was more frequent in men (24.4%) (p = 0.0119) and in individuals aged 40-60 and >60. Gram-negative species showed resistance to ampicillin. K. pneumoniae were resistant to amoxicillin plus clavulanic acid (75.0%), piperacillin plus tazobactam (76.2%), cefotaxime (76.2%), cefuroxime (81.0%), ciprofloxacin (81.0%), and trimethoprim plus sulphamethoxazole (81.0%). Carbapenems were effective against all E. coli and P. mirabilis. Some K. pneumoniae (13.6%) produced metallo-ß-lactamases (MBLs). E. coli (22.6%), K. pneumoniae (81.8%), and all E. faecium were multidrug-resistant (MDR). Some E. coli (26.2%), K. pneumoniae (63.6%), and P. mirabilis (14.3%) isolates produced extended-spectrum beta-lactamases (ESBL). Vancomycin-resistant E. faecium was also found. This study showed that the possibilities of UTIs therapy using available antibiotics become limited due to the increasing number of antibiotic-resistant uropathogens.

Virulence factors, biofilm-forming ability, and antimicrobial resistance of urinary Escherichia coli strains isolated from hospitalized patients.

BACKGROUND/AIM: Escherichia coli is the most frequent cause of urinary tract infections. We investigated the possible associations between the origin of strains, antimicrobial resistance, the presence of urovirulence factors, and biofilm-forming ability. MATERIALS AND METHODS: Antibiotic susceptibility of E. coli strains was tested by disk diffusion method. Hemagglutination assays were performed for phenotypic characterization of the cell surface. Multiplex PCR was used for detection of virulence genes and for determination of phylogenetic relationships. RESULTS: The resistance to ampicillin (55.5%) and tetracycline (39.3%) was significantly more frequent than to other antimicrobial agents. The fim gene was present in 92.5% of strains. The sfa and pap genes were found in 53.8% and 38.7% of strains, respectively. The pap gene was significantly less frequently detected in strains from dialysis patients. The hly gene was present in 18.5% of strains. The aer gene was detected in 52.6% and cnf in 12.1%, while afa was detected in 4.6% of strains. Most strains belonged to the B2 and D phylogenetic groups. The aer gene was significantly associated with strains producing strong biofilms. CONCLUSION: The E. coli strains causing cystitis in hospitalized patients differed in terms of resistance to antibiotics, virulence genes, and potential for biofilm formation.

Antibiofilm activity of trans-cinnamaldehyde, p-coumaric, and ferulic acids on uropathogenic Escherichia coli.

BACKGROUND/AIM: Biofilm on urinary catheters results in persistent infections that are resistant to antibiotics. In this study, phytochemicals were assessed as alternative antimicrobials in preventing and inactivating E. coli biofilm on urinary catheters. MATERIALS AND METHODS: Biofilm prevention was tested using catheter fragments inoculated with E. coli and treated with trans- cinnamaldehyde, p-coumaric, and ferulic acids (0%, 0.1%, 0.25%, and 0.5%) for 0, 1, 3, and 5 days. Inactivation of E. coli biofilm with the same agents at concentrations of 0%, 1%, 1.25%, or 1.5% used for 0, 1, 3, or 5 days was also evaluated. RESULTS: All used concentrations of trans-cinnamaldehyde prevented and effectively inactivated E. coli biofilm formed on urinary catheter fragments. p-Coumaric (0.25% and 0.5%) and ferulic acids (0.5%) had preventive action on E. coli biofilm formation in urinary catheter fragments. The number of uropathogenic E. coli cells in biofilm formed in the lumen of a urinary catheter was significantly reduced in the presence of p-coumaric and ferulic acids, but complete inactivation of the biofilm formed was not observed, as opposed to the use of trans-cinnamaldehyde. CONCLUSION: The obtained results indicate that phytochemicals maybe an important source of antibiofilm agents that have preventive action on E. coli biofilm formation on urinary catheters.

[Susceptibility of Escherichia coli strains isolated from persons with urinary tract infections in 2007 - 2008 to antimicrobial agents]. / Wrazliwosc na antybiotyki i chemioterapeutyki szczepów Escherichia coli wyizolowanych od osób z zakazeniami ukladu moczowego w latach 2007 - 2008.

OBJECTIVE: Determination of sensitivity to antibiotics and chemotherapeutics of 160 E. coli strains isolated from 2007 to 2008 from cases of hospital urinary tract infections and assessment the ability to produce ESBL by these strains. METHODS: The susceptibility of E. coli strains to ampicillin, amikacin, amoxicillin with clavulanic acid, aztreonam, cephalothin, cefotaxime, ceftazidime, cefuroxime, ciprofloxacin, ertapenemem, gentamicin, imipenem, meropenemem, nitrofurantoin, piperacillin, piperacillin with tazobactam, tetracycline, and trimethoprim with sulfamethoxazole was tested by using a disc-diffusion method. Ability to producing ESBL was detected by using double disc synergy test. RESULTS: The analysis revealed a high percentage of strains resistant to ampicillin (56.8%). Strains showing resistance to tetracycline (35%), trimethoprim with sulfamethoxazole (23.1%), ciprofloxacin (19.4%), gentamicin (3.75%) and nitrofurantoin (3.75%) were also obtained. The percentage of strains resistant to amoxicillin with clavulanic acid among those isolated in 2007 was 2.9%, and in group of strains obtained in 2008 was 20.6%. Production of ESBL was observed in 4.4% of strains, which in addition to resistance to penicillin and cephalosporins showed resistance to antibiotics belonging to other groups. Multi-drug resistant strains were also obtained, which did not produce ESBL. CONCLUSIONS: Increasing resistance to some of the antibiotics and the emergence of multi-drug resistant strains clearly indicate the need for continuous monitoring of antibiotic susceptibility in uropathogenic E. coli strains.