ISG Summer Meeting 2024
Clinical Case Presentations
Second Prize

Dr Renuka Sitram
University Hospital, Limerick
ANCA Vasculitis in IBD – when is it significant? A case report
TBA (24S174)
ANCA Vasculitis in IBD- when is it significant? A case report.
Author(s)
R Sitram, M Skelly
Department(s)/Institutions
Department of Gastroenterology, University Hospital Limerick, Dooradoyle, Ireland
Introduction
Antineutrophil cytoplasmic antibodies (ANCA) are known for their association with necrotizing vasculitis, and have also been detected in inflammatory bowel disease. There is a positive correlation of ANCA and disease activity in UC, however differentiating between IBD-associated ANCA and ANCA-vasculitis remains challenging.
Aims/Background
This case focuses on a 28-year male with UC refractory to multiple immunomodulators and biologic therapies, with polyneuropathy and positive ANCA serology. Despite treatment with mesalazine, vedolizumab, and subsequently infliximab plus azathioprine, faecal calprotectin remained elevated, and endoscopy showed MAYO3 pancolitis. He had two hospital admissions with progressive bilateral upper limb paraesthesia and weakness, with complete resolution of symptoms after intravenous methylprednisolone and IVIG.
Method
ANCA and anti-PR3 titres were persistently elevated. Neuroimaging showed pansinusitis and nerve conduction studies revealed bilateral brachial plexopathy. Renal biopsy findings were not consistent with ANCA disease.
Results
A JAK inhibitor was subsequently commenced to treat any potential ANCA vasculitis and IBD, and symptoms improved.
Conclusions
Despite his neurological symptoms, sinusitis and peripheral eosinophilia, it was concluded that this was not ANCA-associated disease, but instead non-specific ANCA serology in the context of ongoing UC disease activity. This case highlights the difficulty in differentiating ANCA-associated vasculitis with IBD-associated ANCA.