Glomerular Diseases in Diabetic Patients: Implications for Diagnosis and Management.

The prevalence of diabetes continues to rise worldwide. In addition to rising rates of diabetic kidney disease, we are also seeing a parallel rise in nondiabetic kidney disease among patients with diabetes. These nondiabetic lesions include focal segmental glomerulosclerosis, IgA nephropathy, membranous nephropathy, and other glomerular diseases. The management of diabetic kidney disease is rapidly evolving to include, beyond glycemic control and renin angiotensin inhibition, the use of sodium-glucose cotransporter 2 (SGLT2) inhibitors and mineralocorticoid receptor antagonists. These and other new treatment strategies should be applicable to managing glomerular disease in diabetic patients to reduce toxicities associated with immunosuppression and, in particular, corticosteroids. The prevalence of glomerular disease in diabetic patients is underappreciated. Diagnosis and appropriately treating these diseases remain an important avenue to modify kidney outcomes in diabetic patients.

Meta-Analysis of Diagnostic Accuracy of Retinopathy for the Detection of Diabetic Kidney Disease in Adults With Type 2 Diabetes.

OBJECTIVES: The study aimed to explore whether diabetic retinopathy (DR) could distinguish diabetic kidney disease (DKD) from nondiabetic renal diseases (NDRDs) in patients with type 2 diabetes mellitus and renal disease. METHODS: We searched PubMed, Embase, Cochrane, MEDLINE and China National Knowledge Internet for articles that enrolled patients with DKD and NDRD. The results were summarized as sensitivity, specificity and the area under the curve of summary receiver operating characteristic curve with their 95% confidence intervals (CIs). RESULTS: A total of 51 studies that included 4,990 participants were collected for evaluation. The overall pooled sensitivity, specificity and area under the curve with their 95% CIs were 0.67 (95% CI 0.61, 0.73), 0.77 (95% CI 0.72, 0.81) and 0.78 (95% CI 0.75 to 0.82), respectively. If the test for DR is negative, the probability of DKD would decrease to 10%, but if the test for DR is positive, the probability would increase only to 42%. In addition, although the mean specificity of proliferative DR for detection of DKD was 0.98 (95% CI 0.92 to 1.00), the mean sensitivity was 0.25 (95% CI 0.16, 0.35). CONCLUSIONS: DR may lack adequate evidence either to verify DKD or to exclude NDRD, and the severity of DR may not parallel the presence of DKD.

Renal Histology in Diabetic Patients.

BACKGROUND: The diagnosis of diabetic nephropathy is based on the course of clinical manifestations and renal biopsy. Renal biopsy is usually performed in patients with atypical presentations. OBJECTIVES: This study was performed to analyze various renal histopathological lesions in diabetic patients and to establish a clinicopathological correlation. MATERIALS AND METHODS: In this retrospective study, the authors analyzed renal histology of 40 patients with type 2 diabetes mellitus who presented with atypical features of diabetic renal involvement and underwent renal biopsy at the Military Hospital Mohammed V, Rabat, Morocco, between January 2008 and December 2016. RESULTS: About 60% of the patients had isolated diabetic nephropathy, 35% had isolated nondiabetic renal diseases and 5% had both. Patients with nondiabetic renal diseases had significantly higher hematuria (P = 0.02), shorter duration of diabetes (P = 0.009), higher mean estimated glomerular filtration rate (P = 0.04) and lower prevalence of diabetic retinopathy (P < 0.001). The most common histological lesion in patients with nondiabetic renal diseases was IgA nephropathy (25%). In patients with diabetic nephropathy, the most common histological class was Class III (42.3%). Furthermore, higher histological classes were associated with lower estimated glomerular filtration rate (P < 0.001) as well as higher prevalence of diabetic retinopathy (P = 0.009) and nephrotic proteinuria (P = 0.04). CONCLUSIONS: This study found that in Rabat, Morocco, the most common histopathological lesion in patients with diabetes was diabetic nephropathy. Hematuria, shorter duration of diabetes, higher mean estimated glomerular filtration rate and lower prevalence of diabetic retinopathy were reported among those with nondiabetic renal diseases. These findings are in accord with that of studies from other countries. However, large sample size and long-term follow-up clinical studies are needed to demonstrate the renal pathological implications and renal outcomes in type 2 diabetes mellitus patients with renal involvement.

Validation of the 2007 kidney disease outcomes quality initiative clinical practice guideline for the diagnosis of diabetic nephropathy and nondiabetic renal disease in Chinese patients.

AIMS: Diabetes mellitus (DM) has overtaken infection and immunological factors as the most common cause of end-stage renal disease. The 2007 Kidney Disease Outcomes Quality Initiative (KDOQI) guideline is a widely accepted guideline for the clinical diagnosis of diabetic nephropathy (DN) and non-diabetic renal disease (NDRD). Our study sought to verify its diagnostic ability in the Chinese population. METHODS: We included 773 patients with DM who underwent a renal biopsy at the Chinese PLA General Hospital from 2007 to 2016. All patients were divided into three groups according to their pathological findings: isolated DN, isolated NDRD, and DN combined with NDRD. RESULTS: Good sensitivity and poor specificity were found for the prediction of NDRD in the Chinese population. Rapidly decreasing estimated glomerular filtration rate, systemic disease, refractory hypertension, and the existence of "grey area" patients may have contributed to the poor diagnostic ability. CONCLUSIONS: The diagnostic ability of the 2007 KDOQI guideline for DN and NDRD was unsatisfactory. The high sensitivity and low specificity of the guideline made it more suitable as screening criteria rather than as diagnostic criteria.

Clinicopathological Features of Nondiabetic Renal Diseases from Different Age Groups: An Observational Cross-sectional Study.

BACKGROUND: Diabetes mellitus (DM) has become the leading cause of chronic kidney disease (CKD). Nondiabetic renal diseases (NDRDs) have different clinicopathological features and prognosis from those of diabetic nephropathy. Our study sought to analyze the clinical and pathological features of NDRDs, in different age groups through a cross-sectional study. METHODS: All patients with type 2 DM at our center who underwent renal biopsy between March 1997 and March 2017 were screened and divided into three groups by age: Group 1 (youth group), 18-44 years old; Group 2 (middle-aged group), 45-59 years old; and Group 3 (elderly group), ≥60 years old. We analyzed the clinicopathological data and risk factors by univariate and multivariate logistic regression for NDRD of the patients to identify the features of NDRD in different age groups. RESULTS: We included 982 patients in the final analysis. Patients with NDRD accounted for 64.4% of all patients. IgA nephropathy (IgAN) was the most common pathological pattern in young patients with NDRD, accounting for 26.3%. In the middle-aged group, the two most common pathological patterns were IgAN and membranous nephropathy. Membranous nephropathy was the most common pathological pattern in elderly patients with NDRD, accounting for 29.3%. Consistent with pathological features, glomerular hematuria is a risk factor for NDRD in Group 1 (odds ratio [OR], 26.514; 95% confidence interval [CI], 2.503-280.910; P = 0.006). On the other hand, rapidly increasing proteinuria or nephrotic syndrome is a risk factor for NDRD in Group 2 (OR, 5.921; 95% CI, 2.061-17.013; P = 0.001) and Group 3 (OR, 90.409; 95% CI, 6.198-1318.826; P = 0.001). CONCLUSIONS: This single-center study showed that the proportion and composition of NDRD differ among different age groups. Consistent with pathological features, some clinical indices such as hematuria and proteinuria showed different features among different age groups.

Clinical and pathological characteristics of non-diabetic renal disease in type 2 diabetes patients.

BACKGROUND: Renal involvement in type 2 diabetes is mainly due to diabetic nephropathy (DN). Nevertheless, a sizable proportion of diabetic patients could actually have nondiabetic renal diseases (NDRDs) or DN plus NDRDs. This study aimed to explore the pathological features of NDRD in diabetic patients and to assess the predictability of diagnosing NDRD (±DN) versus isolated DN on the basis of clinical parameters. METHODS: Medical records of type 2 diabetes patients who underwent renal biopsy under suspicion of NDRD from January 2011 through November 2015 were analyzed retrospectively. RESULTS: A total of 101 patients were enrolled in this study. The most frequent indication for renal biopsy was recent onset of nephrotic syndrome (41%), followed by rapidly progressive renal failure (29%) and active urinary sediment (21%). On renal biopsy, 51% of patients had isolated DN, 20% had isolated NDRD and 29% had DN plus NDRD. IgA nephropathy was the most common cause of isolated NDRD, whereas acute tubular necrosis (39%) and acute interstitial nephritis (33%) were the main causes of NDRD superimposed on DN. Male gender, short-duration diabetes (<8 years), lower glycated hemoglobin and active urinary sediment (≥10 red and white blood cells per high-power field) were independent predictors of NDRD according to multiple logistic regression analysis. CONCLUSIONS: Judicious use of renal biopsy revealed NDRD (±DN) in nearly half of type 2 diabetes patients with atypical renal presentation, especially in male patients with well-controlled diabetes, those who have had diabetes for a short duration and those with active urinary sediment.

Clinicopathological Features of Nondiabetic Renal Diseases from Different Age Groups: An Observational Cross-sectional Study / 中华医学杂志(英文版)

Background@#Diabetes mellitus (DM) has become the leading cause of chronic kidney disease (CKD). Nondiabetic renal diseases (NDRDs) have different clinicopathological features and prognosis from those of diabetic nephropathy. Our study sought to analyze the clinical and pathological features of NDRDs, in different age groups through a cross-sectional study.@*Methods@#All patients with type 2 DM at our center who underwent renal biopsy between March 1997 and March 2017 were screened and divided into three groups by age: Group 1 (youth group), 18-44 years old; Group 2 (middle-aged group), 45-59 years old; and Group 3 (elderly group), ≥60 years old. We analyzed the clinicopathological data and risk factors by univariate and multivariate logistic regression for NDRD of the patients to identify the features of NDRD in different age groups.@*Results@#We included 982 patients in the final analysis. Patients with NDRD accounted for 64.4% of all patients. IgA nephropathy (IgAN) was the most common pathological pattern in young patients with NDRD, accounting for 26.3%. In the middle-aged group, the two most common pathological patterns were IgAN and membranous nephropathy. Membranous nephropathy was the most common pathological pattern in elderly patients with NDRD, accounting for 29.3%. Consistent with pathological features, glomerular hematuria is a risk factor for NDRD in Group 1 (odds ratio [OR], 26.514; 95% confidence interval [CI], 2.503-280.910; P = 0.006). On the other hand, rapidly increasing proteinuria or nephrotic syndrome is a risk factor for NDRD in Group 2 (OR, 5.921; 95% CI, 2.061-17.013; P = 0.001) and Group 3 (OR, 90.409; 95% CI, 6.198-1318.826; P = 0.001).@*Conclusions@#This single-center study showed that the proportion and composition of NDRD differ among different age groups. Consistent with pathological features, some clinical indices such as hematuria and proteinuria showed different features among different age groups.

Nondiabetic Renal Disease in type 2 Diabetes Mellitus Patients: A Clinicopathological Study.

BACKGROUND: The prevalence of nondiabetic renal disease (NDRD) among type 2 diabetics varies widely depending on the populations being studied and the selection criteria. Also, for patients found to have NDRD different predicting factors have been identified by different studies. OBJECTIVES: TO DETERMINE: (i) Frequency and spectrum of NDRD in type 2 diabetics with atypical clinical renal disease, in our set up and (ii) common clinical markers that are associated with NDRD in our local population. MATERIALS AND METHODS: Ninety-three type 2 diabetic patients with atypical clinical renal disease who had undergone renal biopsy to rule out NDRD were recruited. Patients were grouped into Group 1 with isolated NDRD, Group 2 with NDRD superimposed on diabetic nephropathy (DN), and Group 3 with isolated DN; and their clinical and biochemical parameters were statistically analyzed using analysis of variance, Kruskal-Wallis test, and Chi-square tests of statistical significance. RESULTS: 68.8% of the patients had NDRD with or without concurrent DN. Patients with isolated NDRD had shorter duration of diabetes compared to the other groups. Absence of retinopathy and presence of microscopic hematuria and active urinary sediment had positive predictive value of 79.24, 81, and 100%, respectively, for NDRD in type 2 diabetics. Chronic interstitial nephritis was the commonest NDRD and membranous glomerulonephritis was the commonest glomerular NDRD in our setup. INTERPRETATION AND CONCLUSIONS: The frequency of NDRD in type 2 diabetics with atypical clinical renal disease is high in our setup thereby making the renal biopsy procedure imperative to rule out the same. Shorter duration of diabetes, absence of retinopathy, presence of microscopic hematuria, and active urinary sediment are markers associated with NDRD in type 2 diabetes with clinical renal disease.

Nondiabetic kidney disease in type 2 diabetic patients: A single center experience.

Nondiabetic renal disease (NDRD) is seen as a cause of proteinuria and renal failure in type 2 diabetes mellitus (DM). The clinical differences between NDRD and diabetic glomerulosclerosis (DGS) are not clear. This study was done to find the spectrum of NDRD in type 2 DM patients and differences in clinical profile between NDRD and DGS patients. Data of patients with type 2 DM who underwent renal biopsy in this institute from 1990 to 2008 were analyzed retrospectively. Patients were categorized as isolated NDRD, NDRD with DGS, and isolated DGS. A total of 75 patients were included. Mean age was 45 ± 10.2 years, male to female ratio was 3.1 : 1, median duration of DM was 12 months (range, 1 year-15 years), proteinuria was 4.2 ± 3.4 g/day, and serum creatinine was 4.3 ± 3.9 mg/dl. Hypertension was observed in 63 (84%) cases and microscopic hematuria in 24 (32%) cases. Nephrotic syndrome (38.7%) was the commonest clinical presentation. Forty-eight (64%) cases had NDRD and 27 (36%) had DGS. The commonest NDRD was minimal change disease (12.5%). Three (6.3%) patients had lupus nephritis. Tubulointerstitial nephritis has been observed in 10.4% patients. No significant differences between NDRD and DGS patients were found except hypertension which was significantly high in the DGS group. Acute kidney injury and nephritic syndrome were not observed in the DGS group. In conclusion, the incidence of biopsy-proven NDRD in type 2 DM in this study was high. Kidney biopsy aided in the detection of NDRD in clinically suspected patients.