FO033
MALIGNANT NEPHROANGIOSCLEROSIS IN YOUNG PATIENTS WITH MALIGNANT HYPERTENSION

INTRODUCTION AND AIMS: The lesions of nephroangiosclerosis are the histopathological consequences of malignant hypertension (MH) as redefined by ESC2013. The pathophysiology of MH is commonly extrapolated from the essential arterial hypertension and aging processes. Genetic causes are poorly understood, especially in young patients with renal impairment. Some authors even consider the renal disease per se as the very starting point of MH.

METHODS: The objective of our study is to identify both clinical and prognosis data in patients under 40 years old at enrollment receiving a renal biopsy at their diagnosis of MH.

RESULTS: From a retrospective and prospective collection carried out in 5 hospitals in Paris over 30 years (1985-2017), 57 patients have been included. They were men (N=38) and women (N=19) aged from 34 years on average; 31.5% were Caucasians and 26% were African Americans. The diagnosis of an "indeterminate vascular disease" (IVD) has been made in 60% of cases. The diagnosis of a primary glomerulopathy was finally adopted for 21% of the patients, among them 50% of Berger's disease. We did not obverse serious events associated with the renal biopsy procedure. In our selected population, only 3.5% of the patients had normal renal function, 31% required dialysis and 16% were eventually transplanted. Mortality was zero. After multivariate analysis, the only prognostic factor significantly associated with renal prognosis was creatininemia at the time of admission to the hospital (OR = 1.009, 95% CI: [1,004-1,015], p <0.001). Interestingly, no significant pathologic or prognostic differences were found between Caucasians and African-Americans patients.

CONCLUSIONS: IVD / nephroangiosclerosis has been found alone only in 60% of patients in this selected population. Despite the fact that we did not find any renal pathological features on the renal biopsy as a prognosis marker of the disease, our work suggests that a renal biopsy should be performed in any young patient with malignant hypertension. Indeed, the renal biopsy led to the discovery of a superimposed renal disease in more than 21% of all cases. In this small cohort, elevated creatininemia at the time of admission represents the only deleterious marker predictive of End Stage Renal Disease.