The features of idiopathic membranous nephropathy in elderly patients and its correlation with the expression of the expression of phospholipase A2 receptor

Abstract

Objective To investigate the clinico-pathological features of idiopathic membranous nephropathy(IMN)and the expression of phospholipase A2 receptor(PLA2R)in elderly patients. Methods A total of 109 elderly patients with IMN confirmed by renal biopsy at Wuxi People′s Hospital from July 2008 to February 2015 were included.Data were retrospectively collected. Results (1)Participating patients with IMN had a mean age of(67.3±5.4)years, and 67.9% of them had hypertension and 65.1% had nephrotic syndrome.Compared with non-elderly patients, elderly patients had a higher proportion with hypertension(67.9% vs.25.2%)(P=0.000), higher systolic pressure[(143.1±15.2)mmHg vs.(127.3±13.3)mmHg](P=0.000), higher diastolic pressure[(88.4±10.0)mmHg vs.(80.2±8.4)mmHg](P=0.000), more severe tubulointerstitial lesions[(3.1±1.9) points vs.(2.0±1.9)points](P=0.000), and lower eGFR[(70.9±22.9)ml·min-1·1.73 m-2vs.(90.6±27.1)ml·min-1·1.73 m-2](P=0.000). (2)There were more severe tubulointerstitial lesions[(4.7±1.8)points vs.(2.4±1.7)points, 2.9±1.6 points](P=0.000, 0.000)and lower eGFR[(50.4±17.4)ml·min-1·1.73 m-2vs.(80.3±19.7)ml·min-1·1.73 m-2, (72.3±21.4)ml·min-1·1.73 m-2](P=0.000, 0.000)in elderly patients of pathological stage Ⅱ, compared with patients of pathological stages Ⅰ and Ⅰ-Ⅱ.(3)The rate of positive PLA2R was 82.4%.Patients with positive PLA2R had higher proteinuria[(4.5±2.3)g vs.(2.9±1.1)g](P=0.042), lower eGFR[(66.8±21.8)ml·min-1·1.73 m-2vs.(97.7±16.0)ml·min-1·1.73 m-2](P=0.000), and more severe tubulointerstitial lesions[(3.1±2.0)points vs.(1.7±1.1)points](P=0.037)than patients with negative PLA2R.(4)Multiple regression analysis showed that PLA2R positive rate(P=0.008), tubulointerstitial lesion(P=0.000), and level of cholesterol(P=0.025)were negatively correlated with eGFR(R2=0.572). Conclusions Compared with non-elderly patients, elderly patients with IMN have poorer prognosis as a result of higher blood pressure and more severe tubulointerstitial lesions.Elderly patients with IMN of advanced pathological stages and positive PLA2R have more severe kidney injury and tubulointerstitial lesions, resulting in poor prognosis. Key words: Nephropathy, membranous; Pathology, clinical; Receptors, phospholipase A2