Analysis of Treatment Influence on Kidney Function and Brain Non-Contrast MRI Vascular Manifestations of Systemic ANCA-Associated Vasculitis with Renal Involvement

<b>Background</b>: Antineutrophil cytoplasmic antibody-associated systemic vasculitis (AAV) most often involves the kidneys, upper airways and lungs, and peripheral and central nervous systems (PNS, CNS). However, in contrast to PNS, the involvement of the CNS is rarely taken into account in the recognition and assessment of systemic vasculitis, probably because of nonspecific symptoms such as headaches and dizziness, aphasia, memory disorders, or mood changes. In addition, it is not clear whether treatment of systemic vasculitides reduces cerebral vascular alterations. In this study, we aimed to evaluate the effects of AAV treatment on vascular and vasogenic alterations in the brain in patients with acute vasculitis onset with renal involvement. <b>Methods</b>: Twenty-nine patients (17F, 12M, age 60.4 ± 9.8) with AAV relapse with renal involvement were included in the study. The initial baseline assessment and the second evaluation, performed 12.6 ± 2.5 months after the beginning of immunosuppressive treatment, included clinical, neurological, and renal function assessments, along with a brain MRI. <b>Results</b>: Compared with baseline, improvement in clinical, neurological, and renal function was observed during the second clinical evaluation. A significant reduction in the occurrence of vascular dilatation and narrowing in secondary (37.9% vs. 17.2%; <i>p</i> = 0.031) and tertiary (37.9% vs. 10.3%; <i>p</i> = 0.008) cerebral vascular branches was observed. However, the number of vasogenic cerebral white matter lesions detected on the FLAIR sequence increased significantly (36.0 vs. 48.0%; <i>p</i> < 0.001). <b>Conclusions</b>: Intensive immunosuppressive treatment of acute-onset systemic AAV with renal involvement decreases disease activity, improves kidney function, and decreases central nervous system vascular but not vasogenic alterations.