Response of Patients with Medullary Sponge Kidney and Calcium Nephrolithisis to an Acute Acid Load
A defect in distal tubular acidification, consistent with the anatomic site of the lesions, has been reported to occur in a substantial proportion of patients having medullary sponge kidney (MSK) with bilateral tubular ectasia (1). However, a lower incidence of this disorder has been found by others (2) or in patients with unilateral and segmental MSK (3). An increased pH of the tubular fluid within the ectatic lesions could lower the solubility of apatite. This is a frequent constituent of stones produced by MSK patients although calcium oxalate (CaOx) appears to be the most frequent and abundant component of calculi in such patients (4). Defective acidification could be associated with hypocitraturia that may favor CaOx crystallization. On the other hand, hypercalciuria, possibly another manifestation of impaired function of ectatic ducts, has been reported as a frequent lithogenic factor in patients with MSK (5, 6). However, urinary citrate and calcium excretion have not been evaluated, as yet, in connection with urinary acidification in patients with MSK complicated by calcium nephrolithiasis.
KeywordsTitratable Acid Calcium Oxalate Calcium Excretion Oxalate Concentration CaOx Crystal
Unable to display preview. Download preview PDF.
- 2.RA De Fronzo and SO Thier, Functional abnormalities in renal cystic diseases, in: “Cystic Diseases of the Kidney,” KD Gardner, ed., Wiley, New York (1976).Google Scholar
- 4.ER Yendt, Medullary sponge kidney, in: “Diseases of the Kidney,” RW Schrier and CW Gottschalk, eds., Little, Brown and Co., Boston (1988).Google Scholar