AIMS To investigate urinary oxalate excretion in children with urolithiasis and/or nephrocalcinosis and to classify hyperoxaluria (HyOx). METHODS A total of 106 patients were screened. In those in whom the oxalate: creatinine ratio was increased, 24 hour urinary oxalate excretion was measured. Liver biopsy and/or genomic analysis was performed if primary hyperoxaluria (PH) was suspected. Stoo...

The increased urinary oxalate excretion which is characteristic of primary hyperoxaluria causes recurrent urinary calculi and nephrocalcinosis, with death at an early age (Hall, Scowen, and Watts, 1960; Hockaday, Clayton, Frederick, and Smith, 1964), and no effective treatment for the disease has been reported. Glyoxylate is the main immediate metabolic precursor of oxalate, and if the enzyme o...

We use oxalate oxidase from barley seedlings for the colorimetric determination of oxalate in plasma. The oxalate is converted to hydrogen peroxide, which, in the presence of peroxidase, is detected by a Trinder-like chromogenic system. Optimization of the assay, including deproteinization and elimination of interferences from reducing substrates, is described. Ascorbate additions (200 mumol/L)...

A case of primary hyperoxaluria and oxalosis with chronic renal failure, crystalline myocarditis, and disseminated calcium oxalate crystal deposition in various tissues including the brain and meninges is described. Deposition of crystals in brain and meninges is exceptionally rare in primary oxalosis.

Liver-kidney transplantation in patients with primary hyperoxaluria type 1 (PH1) and a high systemic oxalate load is often complicated by oxalate deposition in the renal allograft and loss of renal function. Intensive pre- and post-operative haemodialysis (HD) cannot completely prevent rises in plasma oxalate levels during transplantation because of rebound from saturated oxalate stores. Contin...