Original ArticleInfantile Hypercalcemia and Hypercalciuria: New Insights into a Vitamin D-Dependent Mechanism and Response to Ketoconazole Treatment
Section snippets
Methods
Twenty Caucasian children (12 girls and 8 boys, aged 4 days-17 months) with idiopathic infantile hypercalcemia and hypercalciuria were included in the study because of their serum calcium and urinary calcium/creatinine ratio that was higher than upper reference ranges for the age (2.70 mmol/L and 1.5 mmol/mmoL, respectively). The exclusion criteria included: serum 25-(OH)D levels greater than the threshold of vitamin D overload (100 ng/mL); data, from genetic analysis, scanner, or clinical
Results
Patients' mean age at diagnosis was 65 days (range, 4 days-17 months). The diagnosis had been established fortuitously after a systematic medical check-up (n = 7) or because of growth retardation, feeding difficulties, or weight loss (n = 6), urinary infection (n = 2), or more severe clinical symptoms of hypercalcemia, like dehydratation, decreased appetite, vomiting, lethargy, and hypotonia (n = 5). None of the 9 infants aged <3 weeks, but 10 of the 11 older infants, had unilateral or
Discussion
Infantile benign idiopathic hypercalcemia has been known for >50 years.3, 4, 5 Its mechanism remains poorly understood and the effectiveness of treatment has not been precisely evaluated. Although half the infants we studied had moderately retarded growth and 10 had nephrocalcinosis at diagnosis, all had body weight and length in the normal range, and only 2 still had abnormalities on ultrasound scanning at the end of the survey. Ketoconazole treatment has been shown to decrease serum calcium
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The authors declare no conflicts of interest.