ANALYSIS OF PATOMORPHOLOGICAL MARKERS OF TUBULOINTERSTITIAL FIBROSIS IN PROTEINURIC PATIENTS WITH DIABETIC NEPHROPATHY

Background: The progression of diabetic nephropathy (DN) often accompanies by a combination with non-diabetic glomerulopathies (NDGP), which can significantly affect the prognosis and treatment of patients. However, the information about such influences, in particular, on the severity of tubulointerstitial fibrosis, one of the main pathomorphological prognostic criteria, on the renal parenchyma is not enough. AIM: To investigate the significance of NDGP for fibrotic processes kidney parenchyma in patients with diabetic nephropathy (DN).

Patients (materials) and methods: Single-center retrospective analysis based on medical records of 51 patients (32 men, mean age: 49±13 years) with DN who underwent renal  biopsy between 2002  and 2016. All patients were diagnosed as cases of DN -gr.№1, those were divided  on “pure”  DN-gr.№2 and  DN-gr.№3 with NDGP.

Results:  Out of the 51 DN gr. №1 patients, 30 (60. %) had  gr. № 2, 21 (40. %) had  gr. №3.  IgA nephropathy (IgAN)-20 % was the most common GN followed  by focal  segmental glomerulosclerosis (FSGS)-35%, and  HCV –associated GN was the most common secondary GN. Patients with “pure”  DN had  lower estimated glomerular filtration  rates (eGFR)  and  higher value  of systolic blood pressure  (SBP), glomerulosclerosis ( GS),  peritubular capillarirtis ( PTC) and  myofibroblasts quantity ( SMApositive cells). No significant between-group differences were observed with respect to majority of laboratory and morphological features. The activity of myofibroblasts positively  correlated with tubular atrophy, focal sclerosis, the stage of diabetes and GS in gr. №2 in comparison with gr. № 3.

Conclusions: The fibrosis of tubulointerstitium in the kidney of patients with DN accoppanied the pathomorphological markers such as SMA and  PTC . There wasn’t  significant evidences about the differences of fibrotic processes in the renal  parenchyma in patients with and  without NDHD.

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