Uropathogen distribution and antimicrobial susceptibility in uncomplicated cystitis in Belgium, a high antibiotics prescribing country: 20-year surveillance

Abstract

Treatment of cystitis in primary care is usually empirical, guided by the prior probability of causal pathogens and their susceptibility. To re-evaluate empirical treatment guidelines, the actual distribution and susceptibility of uropathogens was examined and compared with two previous surveys in Belgium over the past 20 years. Because of the alarming increase in carriage of extended-spectrum β-lactamase (ESBL)- and carbapenemase-producing Escherichia coli, this specific resistance was explored. From May 2014 to December 2015, 120 general practitioners collected midstream urine specimens from adult pre- and postmenopausal female patients with suspected cystitis. A dipslide was inoculated and sent for microbiological analysis. Anal swabs were collected for ESBL and carbapenemase detection. Of 265 enrolled patients, 203 (79.3 %) had a positive culture. Escherichia coli (81.6 %) was the most frequently isolated uropathogen, followed by Staphylococcus saprophyticus (8 %), confirming the results of the 1995 and 2005 surveys. The susceptibility of E. coli remained nearly 100 % for nitrofurantoin and fosfomycin, decreased from nearly 100 % in 1995 to 94.2 % for quinolones, from 73.2 to 55.5 % for ampicillin, and from 83.3 to 76.3 % for trimethoprim-sulfamethoxazole (TMP-SMX). In E. coli present in positive urine cultures, ESBLs were found in 2.5 % and carbapenemases were absent. In fecal specimens, ESBL-producing E. coli were found in 7.9 % and carbapenemases were not detected. Over a 20-year period, the distribution of uropathogens in women with cystitis remained unchanged. Susceptibility remained excellent for nitrofurantoin and fosfomycin. For TMP-SMX, ampicillin, and quinolones, there was a decrease.

Women with symptoms of a urinary tract infection but a negative urine culture: PCR-based quantification of Escherichia coli suggests infection in most cases

“…This study is nested within an observational survey on uropathogens and their susceptibility pattern in 256 adult women with symptoms of uncomplicated UTI [4].…”

“…Consecutive studies provide evidence to consider a 'low-count bacteriuria' as a positive result [11,12,14,15]. Yet, even at a lower threshold, one-quarter to onethird of the urine cultures remained negative [3,4], which made some authors question the presence of an infectious agent all together and even propose a psychosomatic explanation for the complaints [15]. This could not explain why even women with a negative culture seemed to benefit from antimicrobial therapy [16,17].…”

“…Recently Hooton et al confirmed that the presence of low counts of Escherichia coli in midstream urine is highly predictive for its presence in the bladder and is not caused by contamination [12]. Although lowering the cut-off rate can explain at least partially the problem of 'negative culture', results in symptomatic women, applying a cut-off rate of 10 3 CFU/mL for E. coli, according to the European Guidelines for Urinalysis, still results in nearly 20% negative cultures [4,13]. This specific group of patients was historically referred to as having the 'urethral syndrome', a condition that has been heavily debated since the 1960s [14,15].…”

Characteristics of the antibiotic regimen that affect antimicrobial resistance in urinary pathogens

“…The bacterium Escherichia coli (E. coli) is by far the most common uropathogen in older adults [ 1 ]. Investigations in residents from long-term care facilities also revealed that the primary indication for antimicrobial (antibiotic) use is a urinary tract infection (UTI) [ 2 ].…”

Pharmacodynamics of Finafloxacin, Ciprofloxacin, and Levofloxacin in Serum and Urine against TEM- and SHV-Type Extended-Spectrum-β-Lactamase-Producing Enterobacteriaceae Isolates from Patients with Urinary Tract Infections

“…Most of the isolates from women with acute, uncomplicated UTIs (uUTIs) were fluoroquinolone susceptible, and extended-spectrum-β-lactamase (ESBL)-producing E. coli strains were almost absent (3–6). However, the prevalence of Enterobacteriaceae producing ESBLs of the TEM, SHV, and CTX-M types has increased significantly in patients with complicated UTIs (cUTIs) (7–13).…”