Introduction:
Diabetes mellitus(DM) is considered as a modern epidemic. The prevalence of DM has risen from an estimated 30 million cases in 1985 to 537 million in 2021. Diabetic nephropathy(DN) is an important complication of DM. Early DN can only be diagnosed by electron microscopy (EM). The literature regarding ultra-structural findings in diabetic nephropathy is scarce. With this study we aim to describe the light microscopic and ultra-structural findings in various stages of diabetic nephropathy and evaluate their predictive role in assessing progression.
Methods:
This was a retrospective observational cohort Study with prospective follow up done from January 2016- December 2019. Patients who are biopsy proven DN with complete EM report were included in the study. Details of the patients were collected retrospectively and follow up data of patients were collected up to one year from date of biopsy. The outcomes for this study were occurrence of renal events (Requirement of dialysis of more than three months or 30% decline in eGFR from baseline at one year) and All-cause mortality. Based on the occurrence of renal events patients were divided into Progressors (patients with occurrence of renal events) and Nonprogressors. Data was analyzed using SPSS.
Results:
A total of 195 patients were included in the study. Mean eGFR was 28.26±22.86, mean ACR was 3068.17±2709 and mean HbA1C was 7.77±1.23. On light microscopy, the most common histological class was class IV in 87(44.5%) patients. GBM thickening, foot process effacement, mesangial matrix expansion and TBM thickening were the most common EM findings. Diabetic fibrillosis was seen in 9(4.6%) patients. 142 people were analysed for the occurrence of combined renal end points, a total of 26 patients had renal outcome (17 with loss of eGFR and 9 requiring RRT). Mean eGFR at baseline showed significant association with development of combined renal outcome at one year. Mean GBM thickness was 767.42±146.08 in progressor group and 649.81±104.38 in the non progressor group. Spherular micro particles, sub epithelial and subendothelial rarefaction was also seen in progressors.
Conclusions:
Diabetic nephropathy is the leading cause of end stage renal disease worldwide. Hence, it is important to identify DN patients at high risk of progression to ESRD and initiate protective renal therapies. Ultrastructural features form an important tool in assessing the prognosis of diabetic nephropathy. Mean GBM thickness and spherular microparticles were the ultrastructural findings significantly correlated with disease progression. In spite of limtations such as Retrospective study with short follow up and not taking into account the treatment received our study demonstrates that the availability of ultrastructural findings will aid in better characterizing the disease progression in DN
I have no potential conflict of interest to disclose.
I did not use generative AI and AI-assisted technologies in the writing process.