![]() described a 16S based real-time PCR using a large number of genus/species specific probes. Some are limited to detection of a single pathogen, or detect only Gram positive or negative bacteria. Molecular based methods for diagnosis of UTI have been described previously. Real-time PCR is increasingly used to diagnose systemic blood infections, or genital infections. Molecular based diagnosis has the advantage that it can identify the cause of UTI within hours. In a hospital associated patient population, like the one in our study, where resistance to antibiotics occurs frequently, evidence based treatment may even be more important. The report however did not confirm that antibiotic resistance of uropathogens had increased over a 10-year period, by contrast to the findings reported by Wagenlehner et al. A study conducted in general practices showed that 27% of patients were treated in the absence of significant bacteriuria. Because of the risk of increasing antimicrobial resistance, it is important to treat only patients with laboratory based evidence of UTI. It has been shown that bacteria causing UTI are increasingly resistant to antibiotics. According to the Infectious Disease Society of America, the definition for evidence of UTI requires growth of 10 3 organisms per ml to diagnose cystitis and 10 5 per ml for pyelonephritis. The ‘gold standard’ for diagnosis of UTI is culture based identification and quantification of organisms. In addition, specimens may be contaminated with mucosal or fecal flora, especially in females. The prevalence of bacteria in the urine may vary from 2% in young females to 10% in elderly asymptomatic women. However, bacteriuria can also occur in asymptomatic persons, depending on the population. Conventional diagnosis is carried out by microscopy and culture to confirm the presence of leucocytes and bacteria in urine culture respectively and takes at least two days. Often, patients are treated on symptoms alone, but the diagnosis of UTI by clinical criteria alone has an error rate of approximately 33%. Virulence factors expressed by these organisms allow for their adherence to the mucosa of the urethra. UTIs are often caused by uropathogens normally residing in the intestines or the genital tract. A national survey in The Netherlands showed that UTIs were the most common healthcare associated infections. Acute uncomplicated urinary tract infections (UTI) are one of the most common bacterial infections, and have a high tendency to recur.
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