Medullary Sponge Kidneyにみられた不完全型尿細管性Acidosisの1例

Abstract

A 34-year-old house wife was first seen on July, 1975 with lumbago and fever, and typical findings of medullary sponge kidney were presented on IVP. While clinical observation was subsequently performed on the out-patient basis for 2 years and 7 months, urine pH level was found to be fixed around 6.5-8.0, although general metabolic acidosis did not exist. She had normal values of GFR RPF, and normal urinary concentrating ability. Endocrine functions including parathyroid function were normal. Biochemical laboratory data were also within normal limits. On ammonium chloride loading test, urine pH did not drop less than 5.5 and NH4+, titrable acids and total H+ excretions were low normal. Normal K and Na clearances and decreased H+ excretion were disclosed with the administration of acetazolamide and sodium thiosulfate. Arterial gas analysis showed normal values of pH and pCO2 and low normal bicarbonate. Those laboratory data indicate that she had medullary sponge kidney associated with incomplete renal tubular acidosis. Disturbances of renal tubular function in medullary sponge kidney were briefly reviewed and a rareoccurrence of the association of incomplete type of renal tubular acidosis in medullary sponge kidney was discussed.