Analysis Of Interstitum Vascular Lesions In IgA Nephropathy And Their Influencing Factors

Objective: To investigate the relationship between the incidence and the severity of the interstitum vascular lesions and clinical-pathological characteristics in patients with IgA nephropathy(IgAN).Methods: 331 cases of IgAN were proved by renal biopsy in our department. Their clinical pathological data were analyzed retrospectively. Blood pressure before renal biopsy, 24 hours urinary protein quantity, serum creatinine, eGFR, serum lipid et al. clinical data and pathologic data of renal biopsy were recorded. All IgAN patients were regard as a whole firstly. The patients were divided into two groups according to whether there is interstitum vascular lesions(thickening and/or hyalinosis of the arteries can be observed via the light microscope). The clinical and pathological data between the two groups were analyzed using between-group comparisons and the multivariate logistic regression analysis. The pathological changes in interstitum vascular were classified according to the katafuchi semiquantitative scoring criteria: Grade 0: no change, Grade 1: 1~2 points, Grade 2: 3~4 points, Grade 3: 5~6 points. The correlation between the severity of interstitum vascular lesions and clinical pathology index was analyzed using Spearman correlation test. The independent risk factors were analyzed using multivariate logistic regression analysis. Vasculopathy of IgAN is traditionally thought to be related with hypertension. The incidence of vasculopathy was still very high in patients without hypertension. To better explore risk factors independent of hypertension for interstitum vascular lesions of IgAN, the normotensive IgAN were screened out in this paper to further explore the risks of the incidence of interstitum vascular lesions using ditto analytical approach.Result: 127 patients(38.4%) were found to have renal interstitum vascular lesions in 331 cases. The incidence of mild, medium and severe vascular lesions were 22.4%, 13.9% and 6.3% respectively. In the patients with renal interstitum vascular lesions, the clinical materials were more serious than that in non interstitum vascular lesions group. The patients with renal interstitum vascular lesions are older, have a higher lever of serum creatinine, uric acid, triglyceride, have a larger quantity of 24 hour urine protein, higher incidence of hypertension, have a reduced eGFR. Their tissue pathological changes were more severe as well, they have a higher pathology grade of Lee, a higher incidence of global and segmental glomeruloselerosis, of moderate to severe mesangial cell and matrix proliferation, of moderate to severe inflammatory cell infiltrate, of moderate to severe interstitial fibrosis, of moderate to severe tubular atrophy. The results of multivariate logistic regression analysis showed that hypertension, moderate to severe tubular atrophy were the independent risk factors for interstitum vascular lesions of IgAN. The Spearman correlation analysis showed that the severity of interstitum vascular lesions were correlated positively with the age, SBP, DBP, 24-UP, Scr, TG et al clinical index, were negatively correlated with eGFR, were correlated positively with the pathologic score of mesangial cell and matrix proliferation, of global glomeruloselerosis, of interstitial fibrosis, of inflammatory cell infiltrate, of severe tubular atrophy. The results of multivariate logistic regression analysis showed that hypertension were the independent risk factors for the severity of interstitum vascular lesions of IgAN. 86 patients(33.99%) were found to have renal interstitum vascular lesions in 253 cases without hypertension. The normal hypertensive patients with renal interstitum vascular lesions are older, have a higher incidence of anaemia, have a reduced eGFR at the time of renal biopsy(increased Scr, decreased eGFR) than non vascular disease group. they have a higher pathology grade of Lee, a higher incidence of global glomeruloselerosis, of moderate to severe mesangial cell and matrix proliferation, of moderate to severe inflammatory cell infiltrate, of moderate to severe tubular atrophy. Over 50 years of age, moderate to severe tubular atrophy,moderate to severe mesangial cell and matrix proliferation were the independent risk factors for interstitum vascular lesions of normal hypertensive IgAN.Conclusion:1. The interstitum vascular lesions of IgAN is common. With the increase of the age of onset, the incidence of interstitum vascular lesion increased gradually.2. The clinical materials and pathological lesions were more serious In the patients with renal interstitum vaseular lesions. Hypertension, moderate to severe tubular atrophy were the independent risk factors for interstitum vascular lesions of IgAN. Hypertension were the independent risk factors for the severity of interstitum vascular lesions of IgAN.3. Interstitum vascular lesions is also common in normal hypertensive IgAN patients. The age, renal dysfunction at the time of renal biopsy, complication of anemia were risk factors of interstitum vascular lesions independent of hypertension.4. The level of uric acid was the influencing factor of interstitum vascular lesions and its severity. No association was found between hyperuricemia and interstitum vascular lesions. The effect of uric acid on IgAN interstitum vascular lesions may be related to blood lipid, hypertension and so on.5. The pathological lesions were more serious in the patients with renal interstitum vascular lesions. The main pathological changes are chronic ischemic pathological changes.