Introduction: Urinary tract infection (UTI) occurs in 1.1% of girls and 1.4% of boys during the first year of life. Asymptomatic bacteriuria (ABU) is usually detected incidentally in 0.9% of girls and 2.5% of boys at this age. The aim of the study was to assess the usefulness of measurement of pro-inflammatory urine interleukin (IL)-6 and IL-8 concentrations and anti-inflammatory transforming growth factor 1 (TGF-1) level in infants with febrile UTI, non-febrile UTI and ABU. Material and methods: A total of 35 children, mean age 6.14 ±3.47 months, were divided into three groups: group I – febrile UTI (n = 13), group II – non-febrile UTI (n = 13) and group III – ABU (n = 9). At the time of enrollment urine IL-6, IL-8, TGF-β1 and serum C-reactive protein (CRP), erythrocyte sedimentation rate (ESR), and white blood cell count (WBC) were measured. Renal ultrasound was performed in all children, 99mTc-dimercaptosuccinic acid scintigraphy (DMSA) and voiding cystourethrography in children with UTI. Results: Urine concentrations of IL-6 and IL-8 were significantly higher in febrile UTI compared to those with non-febrile UTI and ABU (p < 0.5, p < 0.01) and positively correlated with CRP, ESR and WBC (p < 0.01). Urine levels of TGF-β1 were significantly higher in children with febrile UTI compared to those with ABU (p < 0.05) and positively correlated with WBC (p < 0.01). Inflammatory changes in the DMSA scan were detected in 66.6% of children with UTI. No significant difference in frequency of an abnormal DMSA scan compared to a normal scan was found in groups with febrile and non-febrile UTI. No relations between urine cytokines, systemic inflammatory markers and changes in DMSA scan were observed. The cutoff value for detection of inflammatory changes in the DMSA scan for IL-8 was 120 pg/mg creatinine (Cr) and 40 pg/mg Cr for TGF-β1. Based on this value, the sensitivity for IL-8 was 58.3%, specificity 100% and for TGF-β1 66.7% and 83.7%, respectively. Conclusions: We found significant differences in children with febrile UTI and ABU regarding urine IL-6, IL-8 and TGF-β1 levels. Urine cytokines and systemic inflammatory markers do not differentiate between upper and lower UTI in infants.

Chronic kidney disease (CKD) is a multi-symptomatic condition resulting from irreversible functional and structural damage to the kidneys. Therefore, finding a specific and sensitive marker to predict the development and progression of CKD is of great interest. Periostin is a matricellular protein involved in tissue remodeling and wound healing. It is highly expressed in various types of kidney diseases, especially in conditions associated with progressive renal fibrosis, while its expression in healthy kidneys is not significant. Numerous experimental and human adult studies indicate the role of periostin in the pathogenesis of various types of kidney disease, though the mechanism of action of periostin appears to be diverse and varies depending on the conditions. The article summarizes current knowledge on the possible roles of periostin in the pathogenesis of kidney injury and its position as a marker in various human renal pathologies. The studies performed so far indicate the potential of urinary and tissue periostin as a promising biomarker of CKD progression.

Background: Urinary tract infections (UTIs) are one of the most common bacterial infections in children. In children < 7 years of age, the prevalence of one episode of symptomatic UTI has been estimated at 3–7% in girls and 1–2% in boys, whereas 8–30% of them will have one or more episodes of UTI. The use of some probiotics appears to reduce the risk of recurrence of UTIs. Since the effects of probiotics are strain-specific, the efficacy and safety of each strain has to be assessed. The main aim of this study is to determine whether probiotics (containing Lactobacillus rhamnosus PL1 and Lactobacillus plantarum PM1) therapy are effective in preventing UTI in children compared to placebo. Method: A superiority, double-blind, randomised, controlled trial is being conducted. One hundred and six patients aged 3 to 18 years with recurrent UTIs in last year (defined as: ≥ 2 episodes of UTI with acute pyelonephritis/upper UTI; or 1 episode of UTI with acute pyelonephritis and ≥ 1 episodes of UTI with cystitis/lower UTI; or ≥ 3 episodes of UTI with cystitis/lower UTI) or children with ≥ 1 infection in the upper urinary tract and ≥ 1 of recurrent UTIs risk factors (congenital anomalies of the kidney and urinary tract, constipation, bladder dysfunction, myelomeningocele, sexual activity in girls) will be randomly assigned to receive a 90-day prophylaxis arm (probiotic containing L. rhamnosus PL1 and L. plantarum PM1) or a 90-day placebo arm. The primary outcome measure will be the frequency of recurrence of UTI during the intervention and in the period 9 months after the intervention. Discussion: The findings of this randomised controlled trial (RCT), whether positive or negative, will contribute to the formulation of further recommendations on prevention of recurrent UTIs in children. Trial registration number: NCT03462160, date of trial registration 12th March 2018.