Search

A boy with idiopathic Fanconi's syndrome is described who exhibited, in addition to the usual features, an unusually large degree of urinary sodium chloride wastage accompanied by a metabolic alkalosis. No evidence of distal tubular abnormality was found and all urinary findings were explicable on the basis of proximal tubular malfunction. Investigations revealed that a combination of sodium, chloride and potassium depletion produced an alkalosis despite the presence of a low bicarbonate threshold commonly found in this syndrome. Detailed studies suggested that although potassium depletion may play a smaller role than sodium chloride wastage, its effects are real and in some degree mediated by an effect upon proximal tubular bicarbonate reabsorption.

Mild, compensated metabolic acidosis was demonstrated in a group of children with growth retardation of undetermined etiology. In response to administration of a single large dose of ammonium chloride, urinary acidification was normal, but there was a limitation in the rate of excretion of hydrogen ion as titratable acid and as ammonium. Since these children had no other evidence of renal impairment, it is postulated that growth retardation per se modifies renal regulation of acid-base balance through effects on both phosphorus and ammonia metabolism.

194 cord blood samples were studied with both a fluorimetric assay and an electrophoretic method for Gal-1-PUT. From this the expected live birth incidence was 1:37000. The New Zealand neonatal screening programme has detected 5 cases in 223326 live births—an apparent incidence of 1:44600. The Beutler testing of dried blood spots collected on filter paper cards is a satisfactory method of detecting galactosaemia in the neonate.

Calcium and phosphorus balance studies were performed in a child with hypophosphatemic rickets secondary to the Fanconi syndrome. Evidence was obtained of a normal capacity for intestinal absorption of calcium and phosphorus. The data indicated that an increased renal clearance of phosphate with resultant hypophosphatemia was the major determinant in the failure of normal bone formation. This tubular abnormality was corrected by administration of large amounts of vitamin D, but was not influenced by acute hypercalcemia, pointing to a primary tubular defect in reabsorption of phosphorus. Renal excretion of calcium was unrelated to intestinal calcium absorption and was increased despite the presence of alkalosis. The close correlation found between rates of urinary excretion of calcium and sodium suggested a mechanism for the variation in calcium excretion reported in this syndrome.