Purpose: We study the ability of dimercapto-succinic acid (DMSA) scintigraphy to predict the presence of dilating vesicoureteral reflux (VUR) in infants with urinary tract infection (UTI) t...

The objective of this study was to evaluate the basis for diagnosis and assessment of children <2 y of age with urinary tract infections (UTI) and to describe their subsequent management as currently practised in Sweden. The study was a prospective, multicentre project as part of a programme for quality assurance. A total of 2309 children (1111M, 1198F) was studied during a 2-y period. Of the population at risk, 1.6% of both boys and girls were diagnosed with a UTI. This represents a minimum figure. Suprapubic bladder aspiration was mainly used during the first year of life, with the highest frequency in the youngest infants. Adhesive bags were used in half of the children, and the frequency increased with age. Imaging of the urinary tract was performed in 97% of the children. Vesicoureteric reflux was the most common finding, occurring in 36% of the girls and 24% of the boys. The presence of dilatation of the upper urinary tract correlated significantly to the presence and grade of reflux. Initial intravenous therapy was given to 31% of the children and long-term antibacterial prophylaxis to 20%. Major differences were found between centres in diagnostic rate, urine sampling technique and the use of parenteral therapy. In conclusion, this study showed a high diagnostic rate of urinary infections in children below 2 y of age. The urine sampling technique was optimal (suprapubic aspiration) in half of the infants, but less reliable in the children above 1 y of age. The frequency of imaging investigations of the urinary tract was high. The strategies for diagnosis and treatment varied considerably among centres.

Evaluation of renal dysfunction includes estimation of glomerular filtration rate (eGFR) as the initial step and subsequent laboratory testing. We hypothesized that combined analysis of serum creatinine, myo-inositol, dimethyl sulfone, and valine would allow both assessment of renal dysfunction and precise GFR estimation. Bio-banked sera were analyzed using nuclear magnetic resonance spectroscopy (NMR). The metabolites were combined into a metabolite constellation (GFR_NMR) using n = 95 training samples and tested in n = 189 independent samples. Tracer-measured GFR (mGFR) served as a reference. GFR_NMR was compared to eGFR based on serum creatinine (eGFR_Crea and eGFR_EKFC), cystatin C (eGFR_Cys-C), and their combination (eGFR_Crea-Cys-C) when available. The renal biomarkers provided insights into individual renal and metabolic dysfunction profiles in selected mGFR-matched patients with otherwise homogenous clinical etiology. GFR_NMR correlated better with mGFR (Pearson correlation coefficient r = 0.84 vs. 0.79 and 0.80). Overall percentages of eGFR values within 30% of mGFR for GFR_NMR matched or exceeded those for eGFR_Crea and eGFR_EKFC (81% vs. 64% and 74%), eGFR_Cys-C (81% vs. 72%), and eGFR_Crea-Cys-C (81% vs. 81%). GFR_NMR was independent of patients’ age and sex. The metabolite-based NMR approach combined metabolic characterization of renal dysfunction with precise GFR estimation in pediatric and adult patients in a single analytical step.

Shiga toxin (Stx)-producing Escherichia coli (STEC) is an important foodborne pathogen with the ability to cause bloody diarrhea (BD) and hemolytic uremic syndrome (HUS). Little is known about enterohemolysin-encoded by ehxA. Here we investigated the prevalence and diversity of ehxA in 239 STEC isolates from human clinical samples. In total, 199 out of 239 isolates (83.26%) were ehxA positive, and ehxA was significantly overrepresented in isolates carrying stx_2a + stx_2c (p < 0.001) and eae (p < 0.001). The presence of ehxA was significantly associated with BD and serotype O157:H7. Five ehxA subtypes were identified, among which, ehxA subtypes B, C, and F were overrepresented in eae-positive isolates. All O157:H7 isolates carried ehxA subtype B, which was related to BD and HUS. Three ehxA groups were observed in the phylogenetic analysis, namely, group Ⅰ (ehxA subtype A), group Ⅱ (ehxA subtype B, C, and F), and group Ⅲ (ehxA subtype D). Most BD- and HUS-associated isolates were clustered into ehxA group Ⅱ, while ehxA group Ⅰ was associated with non-bloody stool and individuals ≥10 years of age. The presence of ehxA + eae and ehxA + eae + stx₂ was significantly associated with HUS and O157:H7 isolates. In summary, this study showed a high prevalence and the considerable genetic diversity of ehxA among clinical STEC isolates. The ehxA genotypes (subtype B and phylogenetic group Ⅱ) could be used as risk predictors, as they were associated with severe clinical symptoms, such as BD and HUS. Furthermore, ehxA, together with stx and eae, can be used as a risk predictor for HUS in STEC infections.