Prevalence, serotyping and drug susceptibility patterns of Escherichia coli isolates from kidney transplanted patients with urinary tract infections

Evaluating the Effects of Ertapenem and Meropenem on Tacrolimus

Purpose: Further elucidate the potential drug interaction between tacrolimus and carbapenems in order to appropriately maintain the balance between infection treatment and therapeutic immunosuppression. Methods: This study was a retrospective evaluation of solid organ transplant recipients on a stable dose of tacrolimus who received either ertapenem or meropenem. Patients were excluded if they had acute kidney injury, acute liver failure, concomitant initiation of medications that interact with tacrolimus, or were pregnant. The primary endpoint was the change in the median daily tacrolimus dose after meropenem or ertapenem administration. The secondary endpoint was the change in serum tacrolimus levels after meropenem or ertapenem administration. Results: A total of 28 patients on tacrolimus were included in the study, 12 received ertapenem and 16 received meropenem. The median daily tacrolimus dose was 4.5 mg [IQR 3.0 mg - 8.8 mg] prior to and 3.4 mg [IQR 2.3 mg - 8.8 mg] after ertapenem administration. The median daily tacrolimus dose was 3.0 mg [IQR 1.6 mg - 5.5 mg] before and 3.0 mg [IQR 1.6 mg - 5.5 mg] after meropenem administration. No statistically significant difference in regard to the change in the median daily tacrolimus dose after ertapenem (P =.173) or meropenem administration (P =.755) was observed. There was no statistically significant difference found after ertapenem (P =.583) or meropenem (P =.317) administration when comparing pre- and post-administration median serum tacrolimus levels. Conclusion: The administration of ertapenem or meropenem did not affect serum tacrolimus levels or daily tacrolimus dose suggesting against empiric dose adjustments with co-administration.

Aptitude of Uropathogenic Escherichia coli in Renal Transplant Recipients: A Comprehensive Review on Characteristic Features, and Production of Extended Spectrum β-Lactamase

Urinary tract infection is the most common infection in almost half of the renal transplant patients. The development of UTI in these patients may progress to bacteremia, acute T cell-mediated rejection, impaired allograft function, or allograft loss, along with the increased risk of hospitalization and death. Among various pathogens implicated, Uropathogenic E. coli (UPEC), especially sequence type 131 (ST131), is the most virulent and multidrug-resistant pathogen. High antimicrobial resistance to most β-lactam antibiotics, mediated by extended spectrum β-lactamases (ESBLs) produced by UPEC, is a challenge in the clinical management of UTIs in kidney transplant recipients. Indeed, multidrug resistance to β-lactam antibiotics is a direct consequence of ESBL production. Resistance to other antibiotics such as aminoglycosides, fluoroquinolones, and trimethoprim-sulphamethoxazole has also been reported in ESBLs-producing UPEC, which reduces the therapeutic options, rising healthcare-associated costs and subsequently leads to renal failure or even graft loss. In this review, we aimed to discuss the post-transplant risk factors of UTI, UPEC virulence factors (VF), and the related factors including quorum sensing, and stress resistance genes. Furthermore, we searched for the current treatment strategies and some of the alternate approaches proposed as therapeutic options that may affirm the treatment of ESBL-producing UPEC.

In Vitro Activity of New β-Lactamase Inhibitor Combinations against blaNDM, blaKPC, and ESBL-Producing Enterobacteriales Uropathogens

Antibiotic resistance in uropathogens has increased substantially and severely affected treatment of urinary tract infections (UTIs). Lately, some new formulations, including meropenem/vaborbactam (MEV), ceftazidime/avibactam (CZA), and ceftolozane/tazobactam (C/T) have been introduced to treat infections caused by drug-resistant pathogens. This study was designed to screen Enterobacteriales isolates from UTI patients and to assess their antimicrobial resistance pattern, particularly against the mentioned (new) antibiotics. Phenotypic screening of extended-spectrum β-lactamase (ESBL) and carbapenem resistance was followed by inhibitor-based assays to detect K. pneumoniae carbapenemase (KPC), metallo-β-lactamase (MBL), and class D oxacillinases (OXA). Among 289 Enterobacteriales, E. coli (66.4%) was the most predominant pathogen, followed by K. pneumoniae (13.8%) and P. mirabilis (8.3%). The isolates showed higher resistance to penicillins and cephalosporins (70-87%) than to non-β-lactam antimicrobials (33.2-41.5%). NDM production was a common feature among carbapenem-resistant (CR) isolates, followed by KPC and OXA. ESBL producers were susceptible to the tested new antibiotics, but NDM-positive isolates appeared resistant to these combinations. KPC-producers showed resistance to only C/T. ESBLs and carbapenemase encoding genes were located on plasmids and most of the genes were successfully transferred to recipient cells. This study revealed that MEV and CZA had significant activity against ESBL and KPC producers.