P030 Antiphospholipid syndrome and giant cell arteritis: a coincidence or connection?
Authors: Sammut Luke , Htut Ei Phyu 
Published: April 2021

Abstract
Background/Aims
Antiphospholipid syndrome (APS) is a multisystem autoimmune disorder, which can be primary or associated with other conditions including systemic lupus erythematosus. Several studies have reported antiphospholipid antibodies, in patients with different vasculitides but little is known about the occurrence of APS and giant cell arteritis (GCA). We report a case of a patient diagnosed with concomitant extracranial GCA and APS.
Methods
A 74-year-old lady presented to the Emergency department following a fall at home. On further questioning, she reported a rapid history of weight loss (4kg in the previous 4 weeks) but no classical features of giant cell arteritis. Her temporal arteries were pulsatile bilaterally, not tender or thickened. Cranial nerve examination including fundoscopy was normal. Her gait was apraxic, with short stride length and veering to the right with a narrow base. The rest of the examination was unremarkable.
Results
Laboratory investigations showed an elevated CRP 98mg/L with a normal ESR 23mm/h, ferritin 380 ng/ml, negative ANCA and ANA, with an unremarkable myeloma screen. Microbiology investigations demonstrated negative serial blood cultures, hepatitis screen, and quantiferon. She subsequently underwent intracranial imaging [CT and MRI brain with Gadolinium] which did not demonstrate acute pathology. A PET CT confirmed features in keeping with a large vessel vasculitis without aneurysmal formation. She was treated with pulsed IV methylprednisolone 500mg for 3 consecutive days and started on 60mg oral prednisolone daily. Two days after starting this treatment she developed acute onset double vision: ophthalmologic examination revealed new onset right internuclear ophthalmolplegia (INO). A subsequent CT head angiogram showed non critical stenoses in aorta at origins of great vessels, left vertebral artery, and carotids. Interval MRI brain showed a new infarct in pons corresponding with her INO. Bloods revealed triple positive anti-phospholipid antibodies - [IgG anticardiolipin antibody 102 GPL (0-13), anti-β2 glycoprotein I antibodies 59.8 U/ml (0-18), Lupus anticoagulant detected]. She was commenced on warfarin [target INR 2.5] and aspirin. Due to mental health history and large vessel manifestations, she was started on IV Tocilizumab 8mg/kg and her prednisolone dose was reduced to 40mg when her CRP normalised. Following hospitalisation, she had persistent visual disturbance with ongoing poor spatial co-ordination. Although she remained ataxic, her functional mobility improved. She was transferred to a local stroke unit and was discharged home.
Conclusion
In summary, this is a case of GCA and APS, treated with prednisolone, aspirin, warfarin and tocilizumab. There is increasing evidence describing the presence of antiphospholipid antibodies in patients with vasculitis. However, the role of these antibodies in GCA and the clinical significance remains unclear. This case reports highlights the need for physicians to consider APS in patients who have a history of GCA and subsequently develop arterial or venous embolic events.
Disclosure
L. Sammut: None. E. Htut: None.