No abstract

This prospective, multicentre, randomized, double-blind and placebo controlled study was performed to describe the natural course of uncomplicated lower urinary tract infection (UTI). A total of 1143 women 18 y and above, consulting at 18 primary health care centres in northern Sweden for symptoms suggestive of UTI were included. The symptoms urgency, dysuria, suprapubic pain and loin pain were registered, and urine cultures performed at inclusion and follow-up visits 8-10 d and 5-7 weeks later. Associations between all symptoms and bacteriuria or bacterial counts were unpredictable. Eradication of symptoms and bacteriuria and combinations of them were studied in 288 patients placebo treated for 7 d, of whom 39% dropped out after the first follow-up visit. The spontaneous cure rate of symptoms was 28% after the first week, and 37% had neither symptoms nor bacteriuria after 5-7 weeks. Considering the high dropout rate after the first follow-up visit, the spontaneous cure rate of symptoms and bacteriuria was calculated to 24% at the end of study. We conclude that patient near-laboratory tests are required to establish the diagnosis of lower UTI, and the guidelines for diagnosis of UTI need to be revised.

Sonication of implants has been shown to be a promising method for diagnosis of prosthetic infections due to its improved sensitivity, simplicity, and low cost. The aim of the present study was to evaluate the effects of ultrasound performed under different conditions regarding temperature, duration, and composition of sonication tubes on bacterial species often associated with prosthetic infections. We found that ultrasound had an inhibitory effect on bacteria, of which gram-negative bacteria, in particular Escherichia coli, were almost eradicated after 5 min of sonication at 35°C. Gram-positive bacteria were found to be resistant to the effect of ultrasound. Four factors were important for the inhibitory effect of sonication: the type of microorganism, the temperature of the sonication buffer, the duration of exposure to ultrasound (minutes), and the material and composition of the sonication tube in which sonication is performed. On the basis of the results from the present study, we propose a protocol for sonication and recovery of bacteria associated with biofilm on infected implants prior to conventional culture. From the present protocol, we recommend sonication for 7 min at 22°C at the maximum effect which permits survival of gram-negative bacteria.

Recurrent urinary tract infections (RUTIs) pose a major problem but little is known about characteristics of Escherichia coli associated with RUTI. This study includes E. coli from 155 women with community-acquired lower urinary tract infections (UTIs) randomized to one of three dosing regiments of pivmecillinam and aimed to identify associations between the presence of 29 virulence factor genes (VFGs), phylogenetic groups and biofilm formation and the course of infection during follow-up visits at 8-10 and 35-49 days post-inclusion, respectively. E. coli causing persistence or relapse were more often of phylogenetic group B2 and had a significantly higher aggregate VFG score than E. coli that were not detectable at follow-up. Specifically, these E. coli causing persistence or relapse were characterized by a higher prevalence of hemolysis and 12 VFGs (sfa/focDE, papAH, agn43, chuA, fyuA, iroN, kpsM II, kpsM II K2, cnf1, hlyD, malX and usp). KpsM II K2 and agn43a(CFT073) were independently associated with persistence or relapse. No specific combination of presence/absence of VFGs could serve as a marker to predict RUTI. Stratifying for VFGs, seven days of pivmecillinam treatment reduced the prevalence of persistence or relapse of UTI compared with three days. In vitro biofilm formation was not higher among E. coli causing persistence or relapse. The presence of agn43a(CFT073) or agn43b(CFT073) was associated with biofilm forming capacity. In conclusion, our results show potential targets for prevention and treatment of persistence/relapse of UTI and potential markers for selecting treatment lengths and warrant studies of these and new VFGs.