Idiopathic hypercalciuria in children with vesico ureteral reflux and recurrent urinary tract infection

Our aim was to determine association of vesicoureteral reflux [VUR] and idiopathic hypercalciuria in children with recurrent and single episode of urinary tract infection [UTI]. The study group consisted of 45 children with VUR and recurrent UTI, and 2 control groups: 45 normal healthy children [control group 1] and 45 children with VUR and single episode of UTI [control group 2]. Idiopathic hypercalciuria was defined as urine calcium to creatinine ratio more than 0.8 [mg/mg] in infants younger than 1 year old, and more than 0.2 [mg/mg] in older children [without any detectable causes for hypercalciuria]. The study group consisted of 26 [57.8%] girls and 19 [42.2%] boys, with the mean age of 41.14 +/- 22.1 months. Nine [20%] subjects had hypercalciuria. The control group 1 composed of 22 [48.9%] girls and23 [51.1%] boys, with the mean age of 43.98 +/- 16.23 months. In this group, 6 subjects [13.3%] with hypercalciuria were detected. The control group 2 composed of 23 [51.1%] girls and 22 [48.9%] boys, with the mean age of 39.96 +/- 24.2 months. In group 2, 7 subjects [15.6%] with hypercalciuria were detected. Comparison between such results was not statistically significant. Despite reports of different studies about accompanying of hypercalciuria with recurrent UTI with or without anatomical abnormalities, according to the present study, idiopathic hypercalciuria is not a major contributing factor to recurrent UTI in children with VUR

Normal values for random urinary calcium to creatinine ratio in Iranian children

Due to worldwide variations, reference values of urinary calcium to creatinine ratio in pediatric population are not yet well established. To determine normal values for urinary calcium to creatinine ratio and its relation to urinary sodium or potassium, a descriptive [correlation type] study was conducted in 7 to 12 years old healthy children in Urmia, Iran. Primary school children were divided into two sectors and 7 clusters [4 cluster school boys and 3 school girls]. The subjects were randomly selected. Random, non-fasting morning urine samples were obtained from 364 healthy children aged 7 to 12 years during fall 2005 and immediately sent to laboratory to determine urine calcium [Uca], creatinine [Cr], sodium [Na] and potassium [K]. For data analysis, mean and 95th percentile of UCa/Cr and UNa/K were used. Pearson test was used to determine any relationship between UCa/Cr and UNa/K values. For comparison of UCa/Cr and UNa/K values between males and females, Mann-Withny test was used. A total number of 364 children were enrolled in the study. There were 208 [57.1%] males and 156 [42.9%] females. The mean and 95th Percentile for UCa/Cr was 0.11 [0.10 and 0.24 respectively. The mean and 95th percentile for UNa/K were 2.30 [1.42 and 5.21 respectively. There was no significant difference in UCa/Cr and UNa/K between two sexes [P > 0.05]. We found a weak relationship between UCa/Cr and UNa/K [P < 0.01]. UCa/Cr value may differ according to geographic location. For screening purposes, reference values should be determined in each geographic location