Sjögren's syndrome and renal tubular acidosis

Clinical studies were conducted in four cases of Sjogren's syndrome complicated by renal tubular acidosis (group I) and in ten cases of Sjogren's syndrome without this complication (group II). No differences between the two groups were noted in respect to the ages of the patients or the duration of the disease. Hyperglobulinemia and an increase in serum IgG were observed in three of the four cases in group I, but no difference was found in the degree of increase when comparing the two groups. No differences were observed between the two groups when compared using various serologic tests. Marked lymphocytic infiltration was noted in the biopsy specimens of the lacrimal and parotid glands. In the kidney biopsy specimens in three cases of group I lymphocytic infiltration interspersed with plasma cells was conspicuous in the interstitial tissues. No lymphocytic infiltration was noted in one case without hyperglobulinemia but a marked interstitial fibrosis was seen. No remarkable changes were seen in the renal biopsy tissue in four cases of group II. Accordingly hyperglobulinemia of itself does not appear to be the primary cause of renal tubular acidosis in Sjogren's syndrome. Renal changes appear to represent one of several systemic changes occurring in Sjogren's syndrome. Therefore renal tubular acidosis is probably an inherent result of the disease process responsible for the development of Sjogren's syndrome.