Relationship between hydrocarbon exposure and nephropathology in primary glomerulonephritis

摘要

It has been proposed that renal tubular damage and chronic hydrocarbon exposure are causally related to progression of renal failure in primary glomerulonephritis. We examined the relationship between hydrocarbon exposure and morphological parameters of tubulointerstitial damage in 59 patients with biopsy-proven primary glomerulonephritis (proliferative,n=52; membranous,n=7). From a mean follow-up period of 6 years patients were divided into two groups (GP) according to the presence or absence of progressive renal failure (GP 1,n=24 with progressive renal failure) and (GP 2,n=35 without progressive renal failure). The two groups were comparable in age, sex, duration of diagnosis (since the time of biopsy) and blood-pressure control. Patients were blindly assessed for chronic hydrocarbon exposure by a validated questionnaire. Biopsy cylinders were blindly assessed retrospectively for relative interstitial volume of the renal cortex by the point-counting method. In addition an assessment was made of the degree of fibrosis and chronic inflammatory cellular infiltrate.Hydrocarbon exposure score derived from the questionnaire until the time of renal biopsy correlated both with interstitial volume (r=0.55;P<0.001) and serum creatinine (r=0.46;P<0.001). Moreover, interstitial volume also correlated with serum creatinine (r=0.63;P<0.001). Chronic hydrocarbon exposure scores and relative interstitial volume in the renal cortex at the time of renal biopsy was significantly higher in GP 1 than GP 2 (P<0.001). The degree of interstitial fibrosis and chronic inflammatory cellular infiltrate was also significantly higher in GP 1 than GP 2 (P<0.01). At the time of renal biopsy patients from GP 1 had a significantly higher mean serum creatinine than in GP 2 but the degree of proteinuria and proportion of patients with hypertension were similar.The result of this study suggests that chronic hydrocarbon exposure and tubulointerstitial damage are causally interrelated and may be important risk factors in the progression of renal failure in patients with primary glomerulonephritis.