Cellulose phosphate and chlorothiazide in childhood idiopathic hypercalciuria

Long-term follow-up of patients with idiopathic infantile hypercalcaemia

Idiopathic infantile hypercalcaemia (IIH) is a rare disorder of unknown etiology that presents with hypercalcaemia in a child's first year of life. There is only a limited number of published reports of the natural history of this condition, and the long-term prognosis is largely unknown. The presentation, treatment and long-term follow-up of 11 children with IIH treated at our institution since 1993 are described. Hypercalcaemia resolved in the majority of children by the time they were 3 years of age, but nephrocalcinosis and persistent hypercalciuria were common, and, in some cases, urinary calcium excretion increased after initially becoming normal. This study suggests that clinical and biochemical abnormalities may persist for longer than previously reported and implies the need for ongoing surveillance of patients with IIH.

Prednisolone and cellulose phosphate treatment in idiopathic infantile hypercalcaemia with nephrocalcinosis

A girl presented at the age of 8 months with idiopathic infantile hypercalcaemia complicated by hypercalciuria, nephrocalcinosis and failure to thrive. Her hypercalcaemia was partially corrected by prednisolone, but resolved with the addition of cellulose phosphate. Her height and weight showed significant improvement during the treatment period. Cellulose phosphate should be considered in the management of children with idiopathic infantile hypercalcaemia and nephrocalcinosis.

Atypical idiopathic hypercalciuria in an adolescent

Idiopathic hypercalciuria (IH) in adults is recognized as a cause of urolithiasis. If IH is symptomatic, the symptoms are hematuria, renal colic, or obstructive uropathy with or without infection. In children, IH has been linked to the spectrum of urinary symptoms including hematuria, pyuria, dysuria, recurrent urinary infections, abdominal or suprapubic pain, proteinuria, and the frequency-urgency syndrome. Hematuria may appear prior to the appearance of stones, and thiazide therapy appears to prevent stone formation by decreasing urinary calcium excretion. This report describes an older adolescent with hematuria and flank pain. His urinary chemistry values were not consistently typical of IH, but a thiazide trial with withdrawal challenge was diagnostic. His case is remarkable because, though essentially an adult, his disease was typical of prepubertal disease. Adolescents with unexplained urinary symptoms should be evaluated for IH. The urinary calcium-creatinine ratio may not be elevated, and timed urinary calcium may be equivocal. In some cases a thiazide trial may be valuable and cost effective.