Analysis of the influence of clinical and morphological parameters on the risk of small-diameter renal artery fibroelastosis in arterial hypertension and primary chronic glomerulonephritis
Authors: Levitskaya E.S , Batiushin M.M , Khripoun A.V , Kulikovskikh Y.A.V , Akimenko M.A , Voronova O.V 
Published: November 2020

Abstract

Introduction
The study of remodeling of small-diameter renal arteries in hypertension (AH) and primary chronic glomerulonephritis (CGN) is promising. This is due to the high prevalence of CGN and the likelihood of developing chronic renal failure, as well as insufficient information about the process of remodeling the small arterial wall of the kidneys.

Goal
To evaluate the influence of clinical and morphological parameters on the risk of small-diameter renal artery fibroelastosis in patients with AH and CGN.

Materials and methods
The study included 105 patients with AH and CGN. One of the main criteria for inclusion in the study was the presence of indications for performing nephrobiopsy. All subjects underwent a standard clinical and laboratory study, with determination of serum creatinine, of glomerular filtration rate (GFR) (CKD-EPI), detection of daily proteinuria, systolic (SAD) and diastolic blood pressure (DAP), and the degree and stage of AH. That 66 patients had no signs of fibroelastosis of arteries (the first group), and 39 patients had fibroelastosis (the second group). The presence of tubulointerstitial fibrosis (TF) and inflammation (TI), the prevalence of fibrosis were recorded.

Results
In the first group of patients, the level of SAD, established at the stage of inclusion in the study, was 124.33±21.5mmHg, in the second group – 131.15±17.3mmHg. (p=0.09). DAP values were in the range of 81.97±11.2 and 83.08±9.15mmHg. respectively (p=0.59). When analyzing the degree and stage of AH, statistically significant differences were obtained - 1.29±1.05 and 1.82±0.9 degrees (p=0.009), 1.41±1.08 and 2.08±0.9 stages (p=0.002), respectively. The value of creatinine in the first group was 98.33±39.8mmol/l (1.11 mg/dl), in the second group – 131.49±54.4mmol/l (1.49 mg/dl) (p=0.03), GFR - 97.6±40.4 and 69.3±32.5 ml/min/1.73m2 (p=0.0001), respectively. There were no significant differences in the proteinuria of patients in the study groups (3.64±6.2 and 4.1±5.1 g/l, respectively, p=0.42). Analysis of data obtained during morphological examination allowed us to establish more pronounced changes in TF and TI in the study groups (44 and 35 cases of TF (p=0.009), 35 and 29 cases of TI (p=0.025), respectively, groups). In the first group of patients, the prevalence of TF fever was set at 14.1±19.4%, in the second group – 27.95±21.9% (p=0.001).

Conclusions
The leading reasons for remodeling the vascular bed of small-diameter kidneys in AH and CGN are hemodynamic factor and tissue changes in the kidneys. The presence of fibrosis and interstitial inflammation is associated not only with the effects of the main CGN process, but also with the presence of AH. Confirmation of this conclusion is obtained differences in the stages of AH. An result of the study is data indicating that there are no differences in the clinical sign of progression of CGN-proteinuria, that is, the main pathogenetic factor of CGN does not affect of remodeling of the arteries.

Funding Acknowledgement
Type of funding source: None