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The workup and interpretation of urine cultures is not always clear-cut, especially for midstream samples contaminated with commensals. Standard urine culture (SUC) protocols are designed in favor of growth of uropathogens at the expense of commensals. In selected clinical situations, however, it is essential to trace fastidious or new uropathogens by expanding the urine culture conditions (EUC). The aim of our study was to map the microflora in midstream urine specimens from healthy controls by means of EUC, in view of the interpretation of bacterial culture results in symptomatic patients. Midstream urine specimens from 101 healthy controls (86 females and 15 males) were examined using both SUC and EUC. Whilst 73 % of samples examined by SUC showed no growth at 10 colony-forming units (CFU)/mL, 91 % of samples examined by EUC grew bacterial species in large numbers (≥10 CFU/mL). Asymptomatic bacteriuria, as defined by the European guidelines for urinalysis, was detected in six samples with both protocols. EUC revealed 98 different species, mostly Lactobacillus, Staphylococcus, Streptococcus, and Corynebacterium. None of the samples grew Staphylococcus saprophyticus, Corynebacterium urealyticum, or Aerococcus urinae. Samples from females contained higher bacterial loads and showed higher bacterial diversity compared to males. Midstream urine of healthy controls contains large communities of living bacteria that comprise a resident microflora, only revealed by EUC. Hence, the use of EUC instead of SUC in a routine setting would result in more sensitive but less specific results, requiring critical interpretation. In our view, EUC should be reserved for limited indications. [ABSTRACT FROM AUTHOR]

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. [ABSTRACT FROM AUTHOR]