MP096PRIMARY SJOGREN SYNDROME WITH MINIMAL CHANGE DISEASE

Abstract

Introduction and Aims: Glomerular involvement in primary Sjogren Syndrome (pSS) is less studied and minimal change disease (MCD) has rarely been reported. We report 6 cases of pSS with MCD. Methods: Through retrospectively reviewing all SS patients in our hospital in the past twenty years,6 pSS patients diagnosed as MCD by renal biopsy were enrolled as pSS-MCD group. Ten primAary minimal change disease (pMCD) patient with no other accompanying diseases were enrolled as control group. The clinical data and renal pathology were carefully analyzed. B7-1 expression was evaluated through IHC staining in renal biopsy samples. Results: During the past 20 years, 154 patients with kidney injury received renal biopsy among 2770 pSS patients in our hospital. In the 94 patients with glomerular involvement, membranous nephropathy (MN,42%), mesangial proliferative glomerulonephritis(MGN and IgA nephropathy ,18.8%)and MCD(6.4%) were the top three pathologic diagnosis. Most of pSS-MCD patients were females of middle age (37-71ys, female: male= 5:1). They were diagnosed as pSS according to AECG criteria 2002 (dry mouth, dry eyes, positive anti-SSA/anti-SSB antibodies, and labial gland biopsy). Most of them had exocrine symptoms prior to onset of nephrotic syndrome. All pSS-MCD patients presented with severe proteinuria (10.71±6.45, 3.70-19.02g/d), remarkable hypoalbuminemia (14.88±2.74, 12-19.3g/L), mild microscopic hematuria, leukocyturia and normal blood pressure clinically. Only one patient presented with renal tubule acidosis. Five of six cases had hypokalemia (3.0-3.3mmol/L) and hypocalcemia (1.65-2.05mmol/L). Two female with severe proteinuria (17.69-19.02g/ 24h) showed renal function impairment (Scr 151-200μmol/L). Compared with pMCD group, pSS-MCD patients had higher IgG level (8.94±2.76 g/L vs 4.99±2.21g/L, P=0.006), lower serum cholesterol level (8.49±3.58 mmol/L vs 12.29±3.00 mmol/L, P=0.03)and longer PT( 11.48±0.73s vs 10.35±0.49s, P=0.001 ). As for renal biopsy, pSS-MCD showed normal glomerular appearance under light microscope and diffused effacement of podocyte foot processes under the electron microscope. Focal thickened TBM and interstitial infiltration of mononuclear cells were observed in three patients. B7-1 expression were not observed on podocytes in IHC staining. Steroid (1mg/kg/d) was given to all patients. The improvement of proteinuria was observed in 5 patients (9.31±6.11 g/24h vs 0.90±1.38 g/24h, P=0.03) and renal function returned to normal (54-104μmol/L). The one patient who did not respond to steroid received treatment for tuberculosis. Conclusions: We review glomerular involvement of pSS and report six cases of pSS with MCD, who presented with typical nephrotic syndrome and were responsive to steroid treatment.