As understood today, renal tubular acidosis is a derangement characterized by an impairment of acidifying the urine despite systemic acidosis, even though glomerular function is intact.1 Well-established diagnostic criteria define the disorder as a clinical entity,1-5,19 but recognition, as a rule, is delayed until symptoms of the associated nephrolithiasis stimulate further investigation. Since nephrocalcinosis and nephrolithiasis are secondary manifestations of the disorder, the diagnosis, in most instances, is not made early in the course of the disease.
In the case to be presented here the disorder has been encountered in an exceptionally early stage. Symptoms of hypokalemia alone dominated the clinical picture without any suggestive evidence of kidney stones or intrinsic renal disease. Following basic workup the diagnosis has been substantiated by a positive ammonium chloride loading test and has been amplified by x-ray studies and a percutaneous biopsy of the kidney.
Report of Case
A 30-year-old Negro