Outcomes of intensive care patients with acute small-vessel vasculitis: a 23-year single-centre experience.

OBJECTIVES: Patients with fulminant small-vessel vasculitis (SVV) may require intensive care unit (ICU) admission, where mortality is high. We describe outcomes and prognostic factors in ICU patients with ANCA-associated vasculitis (AAV) and anti-glomerular basement membrane (anti-GBM) disease over a 23-year period. METHODS: Patients admitted with acute manifestations of new or flaring AAV or anti-GBM disease were identified from our hospital ICU database (1999-2022). Patients treated solely in high-dependency areas were excluded. Primary outcomes were mortality at 30 and 90 days and development of end-stage kidney disease (ESKD). A matched case-control analysis (1:4) adjusted for age, gender, APACHE II score and admission year was performed for a patient subgroup. RESULTS: 85 cases (82% AAV, 15% anti-GBM) were identified, 80% newly diagnosed. Median APACHE II score was 19. Ventilatory support and continuous venovenous haemodiafiltration were required in 92% and 66% of cases, respectively. 30-day and 90-day mortality rates were 15% and 26%, respectively. Among 90-day survivors, 17 (28%) developed new ESKD. Vasculitis treatments included cyclophosphamide (59%), rituximab (53% of AAV patients) and plasma exchange (71%). These treatments were associated with 90-day and long-term survival. Treatment for vasculitis post-2008 was associated with 90-day and long-term survival, which was not mirrored in ICU controls. This coincided with improvements to the vasculitis service and therapeutic strategies. CONCLUSIONS: This single-centre study reports ICU outcomes for patients with fulminant SVV over 23 years. 30 and 90-day ICU mortality were comparable with other reported values. Improvement in mortality was associated with changes in vasculitis treatment protocols.