E118 Takayasu’s arteritis in a patient with Crohn’s disease and recurrent pituitary abscesses: a diagnostic and therapeutic challenge

Background/Aims Takayasu’s arteritis (TA) is a rare large vessel vasculitis (LVV) typically affecting individuals under the age of 50 and often described as “pulseless disease”. Its co-existence with Crohn’s disease (CD) has been increasingly reported, raising the possibility of a shared pathophysiological mechanism. In several reports, CD precedes TA, suggesting that TA may represent a rare extra-intestinal manifestation. We present a diagnostically complex case of a young female with recurrent granulomatous pituitary abscesses, CD and undifferentiated inflammatory arthritis, later diagnosed with TA. Methods A 36-year-old female with a complex history has been under long-term endocrinology follow-up for recurrent granulomatous pituitary abscesses. Her first two episodes occurred three years apart and were managed surgically. Following her second recurrence, she was also diagnosed with CD, which has been managed by gastroenterology. Rheumatology then identified undifferentiated, self-limiting inflammatory arthritis after she presented with flitting arthralgias and tenosynovitis confirmed on ultrasound. Initial immunosuppressive treatment for CD included corticosteroids, adalimumab, and later infliximab, which effectively managed her multisystem symptoms but were discontinued due to immunogenicity, as evidenced by recurrence of her pituitary abscesses. She was maintained on low-dose azathioprine with plans by the gastroenterology team to initiate risankizumab to manage her multi-system disease. Results Coinciding with the recurrence of pituitary abscess, she re-presented to Rheumatology with 3 weeks’ history of left shoulder pain and upper limb claudication and was found to have absent radial and brachial pulses on clinical examination. CT angiography confirmed large vessel vasculitis, with retrospective review of 2020 imaging suggesting subtle focal LVV changes, likely suppressed previously by corticosteroids and TNF inhibition. PET-CT and MRI aorta confirmed active vasculitis. After discussion in the connective tissue disease and sarcoid multidisciplinary teams, a diagnosis of Takayasu’s arteritis was established. She commenced prednisolone (30 mg daily) and, in collaboration with endocrinology and gastroenterology, was initiated on certolizumab, given prior efficacy of TNF inhibition. Azathioprine was continued. Steroids were successfully weaned following certolizumab initiation. She experienced significant symptomatic improvement, inflammatory markers normalised, and repeat MRI brain showed resolution of her pituitary abscess. Conclusion This case highlights the rare progression from recurrent granulomatous pituitary abscesses to Crohn’s disease, inflammatory arthritis, and ultimately Takayasu’s arteritis. It also highlights the importance of multidisciplinary input in diagnosis and therapeutic decision-making, particularly where treatment strategies must balance complex multi-organ disease. Furthermore, it supports the concept of possible shared pathological mechanisms among granulomatous pituitary lesions, CD, and TA, suggesting that Takayasu’s and aseptic pituitary abscess may represent systemic extraintestinal manifestations of Crohn’s. Finally, it demonstrates the role of TNF inhibitors as effective therapeutic options in patients with overlapping inflammatory disorders when tailored in a multidisciplinary context, thus avoiding unnecessary surgery in the last 2 episodes of pituitary abscess recurrence.