E161 Cotton wool spots as a potential early sign for giant cell arteritis

Background/Aims Giant cell arteritis is a potentially sight-threatening vasculitis requiring prompt recognition and treatment. Occult GCA is a recognised variant where patients present primarily with visual symptoms and minimal systemic features. Early ophthalmic signs can be subtle, but cotton wool spots (CWSs) may be a rare and under-recognised clue, especially in the absence of obvious causes. In GCA, their presence indicates ischaemic damage due to occlusion of the short posterior ciliary arteries. Methods An 80-year-old man with rheumatoid arthritis on rituximab presented to the optometrist with flashing lights and foggy vision in the right eye. The visual acuity was 6/10 (right) and 6/6 (left). Optical coherence tomography showed ischaemic changes in the right eye. Five days later, ophthalmology review showed visual acuity of 6/12 Rt and 6/7.5 Lt. Fundus exam revealed multiple CWSs and a lamellar macular hole in the right eye; the left eye appeared normal. Tests for diabetes and hypertension were initiated but were unremarkable. 2 weeks later, he returned with sudden vision loss in the left eye. CRP was 139 mg/L; ESR 120 mm/hr. Fundus exam showed posterior synechiae and CWSs in the right eye; the left eye had optic disc swelling with no light perception in both eyes. He denied any headache, jaw claudication or PMR symptoms but reported scalp tenderness. Given high suspicion for GCA, oral prednisolone 100 mg was started, followed by hospital admission for intravenous methylprednisolone. Results He received 2 doses of IV methylprednisolone (500 mg) and IV tocilizumab (8 mg/kg) instead of rituximab. Temporal artery ultrasound showed intimal thickening and non-compressibility bilaterally. Temporal artery biopsy confirmed GCA. His hospital course was complicated by visual hallucinations, delirium and aspiration pneumonia, leading to death six weeks later. Conclusion This case highlights CWSs as a potential early fundoscopic marker of GCA. While commonly associated with diabetes and hypertension, isolated CWSs in patients without cardiovascular risk factors should prompt consideration of GCA. Their recognition should prompt immediate investigation and management to prevent irreversible vision loss. Disclosure H.J. Osagie: None. M. Ghaffar: None. M. Rahman: None. D. Makkuni: None.