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The oculocerebrorenal (Lowe) syndrome is an X-linked recessive disorder characterized by congenital cataracts, hypotonia, developmental delay, poor growth and renal tubular dysfunction. Although the disorder has been mapped to chromosome Xq24-26, the underlying metabolic defect remains unknown. The renal component of the Lowe syndrome comprises tubular dysfunction, that is tubular proteinuria and generalized aminoaciduria progressing to the renal Fanconi syndrome, with later glomerular disease. Clinical problems typically include polyuria, acidosis, hypophosphatemia with rickets and eventually end stage renal disease. Hypercalciuria and its sequelae (nephrocalcinosis and nephrolithiasis) have not been described as cardinal features of the untreated disorder although they reportedly complicate vitamin D and calcium therapy of rickets. We discuss 5 boys with congenital cataracts, hypotonia, developmental delay, failure to thrive and the renal Fanconi syndrome who were diagnosed with the Lowe syndrome and in whom hypercalciuria was documented at diagnosis. We conclude that hypercalciuria and its sequelae may occur commonly in patients with the Lowe syndrome as a component of tubular dysfunction or a complication of therapy.

A case is reported of incomplete renal tubular acidosis (type 1) associated with medullary sponge kidney followed by nephrocalcinosis. Although several cases of classic renal tubular acidosis associated with medullary sponge kidney have been documented a case of incomplete renal tubular acidosis associated with medullary sponge kidney seems to be rare. We recommend examination for incomplete renal tubular acidosis in patients with medullary sponge kidney and nephrocalcinosis without systemic acidosis.

Management of most patients with calculous disease has been less than ideal in the past. Too often therapeutic efforts were limited to symptomatic calculi. Stones were allowed to pass or were removed, metabolic studies were incomplete, victims were dismissed and forgotten, and prophylactic measures were negligible and usually confined to milk restriction and use of distilled water. More patients were crippled with and died of recurrent calculous disease, urinary infection and progressive renal insufficiency than from any other upper urinary tract abnormality. During the last decade the development of a renal stone clinic at this institution has allowed a nephrourologic approach to the management of urolithiasis. This account of classification, diagnosis and management of the various syndromes associated with urolithiasis is based on the experiences gained during the last decade with this common but ill-understood urologic problem.