Multiple renal tubular defects. Report of a case with vasopressin-resistant polyuria, amino-aciduria and incomplete renal tubular acidosis.

Abstract

With an increasing understanding of normal and abnormal renal tubular function during the past several years, a wide spectrum of tubular transport defects have been described. These may occur singly as in renal glycosuria, vitamin D-resistant rickets, and nephrogenic diabetes insipidus, or they may present as multiple defects as in the Fanconi syndrome with glycosuria, phosphaturia and amino-aciduria. 1 Many of the tubular defects in this spectrum of disorders are poorly understood and therefore not clearly defined. The case cited below presented with polyuria as his only symptom of renal tubular dysfunction, but after several studies were performed he was found to have not only vasopressin-resistant diabetes insipidus but also amino-aciduria and incomplete renal tubular acidosis. It is of interest that the patient's disorder was not recognized until he was 54 years of age, even though the abnormalities were probably present since childhood. Report of Case First Admission.— A 54-year-old