Nephrology & Hypertension

Biography

Biography: Joana Manuel Tavares

Abstract

INTRODUCTION AND AIMS: In Europe the incidence of pauci-immune glomerulonephritis, the most common cause of crescentic glomerulonephritis, has presented an increasing trend until the beginning of the millennium. We wanted to analyze retrospectively the characteristics, the presentation and long-term outcomes of our cohort of ANCA-associated vasculitis (AAV) diagnosed patients in whom a biopsy was performed.  

METHODS:  In 28 patients with the diagnosis of AAV with a current histological evaluation available between 2007 and 2016, demographic, clinical and laboratorial data and respective outcomes were analyzed. The patients were divided into two groups according to serum creatinine (sCr) at initial presentation and then classified if sCr <4 mg/dL as Mild Renal Injury (Mild RI) and if sCr ≥ 4 mg/dL as Severe Renal Injury (Severe RI). Comparisons between groups were explored using the Mann-Whitney test for continuous variables and chi-square test for categorical variables. Follow-up was made until dialysis dependency, death or until the 31 st of December of 2017 (at least one year of follow-up after biopsy). Predictors to dialysis or death were explored with multivariable Cox regression.

RESUTLS: The cohort had a median age of 71 (IQR 60-79) years old and was followed-up during a median time of 52 (IQR: 18-72) months. In the group of severe RI, patients were significantly older (p=0,024), had higher proteinuria (p=0,045) and less extra-renal manifestations (p=0,047). Dialysis free survival was also significantly lower in this group (29% vs. 77%; p=0,008). There were no differences in associated comorbidities or in the urine analysis between both groups. Independent predictors of dialysis dependency in our cohort were female gender (HR 14,6; p=0,009), proteinuria (HR 1,79 per unit; p=0,006) and entry sCr (HR 1,65 per unit; p=0,009). In terms of treatment, plasma exchange added to corticoids (CT) plus cyclophosphamide (CPP) was used more frequently in patients with higher sCr (median 6,85 mg/dL vs. median 3,16 and 3,40 mg/dL in the groups of CT and CT + CPP, respectively; p=0,023) but in the end the choice of treatment hasn’t proved to be different to avoid dialysis. 5 patients died and the only predictor of death found was the entry sCR (HR 1,39 per unit; p=0,03). On the other hand, 13 patients remain independent of dialysis with an average creatinine of 1,34±0,62 mg/dL at the end of follow-up. Predictors of renal function found were the age, for each 10 years (β= - 0,30; p=0,04), MPO against PR3 (β=1,48; p=0,007), hypertension (β=1,103; p=0,018)  and presence of crescents (β=1,232; p=0,014).

CONCLUSIONS: Patient survival as well as renal function maintenance was dependent of entry sCr, with higher values being related with poorer outcomes. Female gender and proteinuria were independent predictors of dialysis dependency but not death predictors. Plasma exchange was added in the presence of a worse renal function but in our cohort, differently from the literature, it did not seem to change the prognosis.  Essentially and independently of the therapeutics given it is necessary a high suspicion to lead to an early diagnose and treatment.