Prevalence and Symptoms of Idiopathic Hypercalciuria in Primary School Children of Tehran

Objective: determining prevalence of idiopathic hypercalciuria (ih) in primary school children oftehran.material & methods: we evaluated 778 primary school children (age 6-11, mean 9.1 years) in twosteps: first (screening test), we measured urine calcium to urine creatinine ratio (uca/ucr) and in thesecond step (definitive test), for those children who had uca/ucr ratio more than 0.21 mg/mg wemeasured 24 hours urine calcium excretion. children with secondary forms of hypercalciuria wereexcluded from the study. children with idiopathic hypercalciuria were evaluated for manifestations ofih.findings: among 778 children, 195 (25.1%) had uca/ucr ratio more than 0.21 mg/mg, but fromthese 195 children only 128 children delivered 24 hours urine samples. among these 128 children forwhom 24 hours urine calcium measurements were done 28 children excreted more than 4mg/kg/daycalcium without hypercalcemia or any other known causes of hypercalciuria and we defined them ashaving idiopathic hypercalciuria. if all 195 suspicious cases of ih had delivered 24-hrs urine sampleswe would have 42 cases of ih.conclusion: prevalence of ih in our children was 5.4% and its manifestations were: hematuria,dysuria, recurrent abdominal pain, urinary incontinence, urgency, urinary tract infections andurolithiasis.