Nondiabetic kidney diseases in type 2 diabetic patients

Abstract

BackgroundThe aim of this study was to evaluate the clinical characteristics of nondiabetic nephropathy in type 2 diabetes mellitus patients and to find a clinical significance of renal biopsy and immunosuppressive treatment in such a patient.MethodsRenal biopsy results, clinical parameters, and renal outcomes were analyzed in 75 diabetic patients who underwent kidney biopsy at Chungnam National University Hospital from January 1994 to December 2010.ResultsThe three most common reasons for renal biopsy were nephrotic range proteinuria (44%), proteinuria without diabetic retinopathy (20%), and unexplained decline in renal function (20.0%). Ten patients (13.3%) had only diabetic nephropathy (Group I); 11 patients (14.7%) had diabetic nephropathy with superimposed nondiabetic nephropathy (Group II); and 54 patients (72%) had only nondiabetic nephropathy (Group III). Membranous nephropathy (23.1%), IgA nephropathy (21.5%), and acute tubulointerstitial nephritis (15.4%) were the three most common nondiabetic nephropathies. Group III had shorter duration of diabetes and lesser diabetic retinopathy than Groups I and II (P=0.008). Group II had the lowest baseline estimated glomerular filtration rate (P=0.002), with the greatest proportion of renal deterioration during follow-up (median 38.0 months, P<0.0001). The patients who were treated with intensive method showed better renal outcomes (odds ratio 4.931; P=0.01). Absence of diabetic retinopathy was associated with favorable renal outcome in intensive treatment group (odds ratio 0.114; P=0.032).ConclusionRenal biopsy should be recommended for type 2 diabetic patients with atypical nephropathy because a considerable number of these patients may have nondiabetic nephropathies. And intensive treatment including corticosteroid or immunosuppressants could be recommended for type 2 diabetic patients with nondiabetic nephropathy, especially if the patients do not have diabetic retinopathy.

Idiopathic membranous nephropathy in patients with diabetes mellitus: a diagnostic and therapeutic quandary!

“…The incidence of these NDRDs varies between 18% and 80% among different studies based on the indication used for renal biopsy [ 10 , 11 ]. MN is a common primary glomerular disease seen in diabetic patients [ 6–8 ]. Others include IgA nephropathy, focal segmental glomerulosclerosis, membranoproliferative glomerulonephritis and minimal change disease [ 12 ].…”

“…Membranous glomerulopathy is a common cause of primary glomerular disease in diabetics [ 6–8 ]. It can occur either as an isolated lesion or superimposed with diabetic nephropathy (DN).…”

Kidney biopsy can help to predict renal outcomes of patients with type 2 diabetes mellitus

“…However, not every patient with DM proceeds to renal insufficiency caused by DKD, but also caused by other GNs. Many previous studies showed that the proportion of NDKD was high, at up to 83%, although the ranges were broad [22,23]. Because of this heterogeneous nature, it is hard to predict the progression of renal insufficiency in diabetic patients.…”

“…Furthermore, a significant proportion of patients with DM have non-DKD (NDKD). Previous studies showed that the prevalence of NDKD ranged from 3% to 83% among patients undergoing renal biopsies [12][13][14][15][16][17][18][19][20][21][22][23]. The prognosis of patients with DKD tends to be worse than those with NDKD, and appropriate treatment is different for each disease.…”

Collapsing glomerulopathy superimposed on diabetic nephropathy

“…Renal biopsy is required only in specific circumstances when an NDKD is suspected [Table 2]. [112] Various forms of glomerular diseases may superimpose on DN. [12] Histologically, DN is characterized by excessive accumulation of extracellular matrix with mesangial expansion and glomerular basement membrane thickening.…”