Timing of kidney biopsy in type 2 diabetic patients: a stepwise approach

Jyh-Tong Hsieh,Der-Cherng Tarng,An-Hang Yang,Fu-Pang Chang,Chih-Yu Yang

doi:10.1186/s12882-020-01794-w

Abstract

BackgroundDiabetic nephropathy (DN) is the most prevalent cause of renal disease in type 2 diabetic patients and is usually diagnosed clinically. A kidney biopsy is considered when non-diabetic renal disease (NDRD) is suspected, such as rapid progression in renal function impairment and severe proteinuria. Still, there is yet no consensus on the timing of kidney biopsy in type 2 diabetic patients. This study aims to identify markers that can help differentiate between DN and NDRD and guide the decision of kidney biopsy.MethodsWe retrospectively reviewed patients with type 2 diabetes who received kidney biopsy from 2008 to 2017 at Taipei Veterans General Hospital. Ophthalmologist consultation and outpatient records, diagnosis of kidney biopsy, laboratory data, and clinical characteristics were collected.ResultsThis study enrolled 160 type 2 diabetic patients, among which 120 (75%) had isolated DN and 40 (25%) had NDRD ± DN (26 had isolated NDRD, and 14 had NDRD superimposed on DN). In multivariate logistic regression analysis, DM duration (odds ratio [OR]: 0.907; 95% confidence interval [CI]: 0.842–0.977; P = 0.01), diabetic retinopathy (OR: 0.196; 95% CI: 0.061–0.627; P = 0.006), and urinary RBC (OR: 1.068; 95% CI: 1.024–1.115; P = 0.002) were independent predictors of NDRD. In patients with diabetic retinopathy (n = 112, 70%), the presence of proliferative diabetic retinopathy, pan-retinal photocoagulation, and hematuria were factors predicting NDRD; and in patients without diabetic retinopathy (n = 48, 30%), short DM duration and hematuria were factors predicting NDRD.ConclusionsUsing diabetic retinopathy, DM duration, and hematuria, we developed a 3-step approach to stratify patients into three categories with the different likelihoods of having NDRD. Then different strategies could be taken accordingly. Our stepwise approach is easy to follow and may serve as an appropriate and useful tool to help clinicians in making decisions of kidney biopsy in type 2 DM patients presenting with kidney diseases.

Highlights

Diabetic nephropathy (DN) is the most prevalent cause of renal disease in type 2 diabetic patients and is usually diagnosed clinically
Demographic and clinical data were collected from medical records, including age, gender, height, weight, body mass index (BMI), duration of diabetes mellitus (DM) before the biopsy, ophthalmic findings, and treatment received for diabetic retinopathy before biopsy
We examined factors reflecting the severity of diabetic retinopathy, including Proliferative diabetic retinopathy (PDR), Macular edema (ME), and specific treatment received

Summary

Introduction

Diabetic nephropathy (DN) is the most prevalent cause of renal disease in type 2 diabetic patients and is usually diagnosed clinically. A kidney biopsy is considered when non-diabetic renal disease (NDRD) is suspected, such as rapid progression in renal function impairment and severe proteinuria. Type 2 diabetes mellitus (DM), with its increasing prevalence, is one of the most crucial health problems [1, 2], and diabetic nephropathy (DN) is the leading cause of kidney failure with replacement therapy worldwide [3, 4]. A kidney biopsy is not mandatory for diagnosing DN; otherwise, a biopsy should be considered when patients present with atypical features for DN and a non-diabetic renal disease (NDRD) is suspected. Diabetes-independent factors can cause kidney injury even in patients with DM, resulting in different types of NDRD such as hypertensive nephrosclerosis, atheroembolic. Patients with NDRD will be treated as DN, and their outcomes will be jeopardized without proper therapy

Objectives

Methods

Results

Discussion

Conclusion