Case Presentation: A 62-year-old male with hypertension, CAD s/p CABG, atrial fibrillation on oral anticoagulation, type 1 diabetes s/p pancreatic and renal transplant in 1999 on maintenance Tacrolimus and Mycophenolate presented to the ED complaining of severe headache and confusion. He was very agitated and unable to follow commands. At one point, he was sitting on the floor and needed help to get back to the bed because he was unable to see. The patient was given Lorazepam and a sitter was provided for safety. Once he calmed down, he reported headache, neck pain, and shoulder pain that began 6 days prior. The patient was previously seen at another facility 2 days prior to this admission and was sent home on muscle relaxants.On exam, HR 93 bpm, BP 193/93mmHg, RR 18, and temperature 99.3F. He was somnolent and his neck was rigid and tender to palpation. The patient did not cooperate for a complete neurological exam, but his vision was notably diminished to counting fingers on the right side. Pertinent labs included hemoglobin 12.6 g/dL and creatinine 1.7mg/dl. Other investigations including VDRL, ANA, TSH, vitamin B12, LFTs, Hepatitis and HIV serologies were negative. CT head, MRI head and neck were negative for acute abnormality. Lumbar puncture was performed, and empiric IV Ampicillin, Ceftriaxone, and Acyclovir were initiated due to concern for meningitis and encephalitis. CSF work up for infectious, autoimmune, paraneoplastic etiologies was negative. Antibiotics and antivirals were subsequently discontinued. His vision loss was intermittent, and he later endorsed extreme tenderness on his temporal and cervical areas. CRP came back at 17mg/dL. IV Methylprednisolone was started for Giant Cell Arteritis (GCA), with rapid resolution of headache, vision loss, and confusion. Rheumatology was consulted and recommended discharge on a 2-week course of PO Prednisone 60mg once daily with plan for outpatient temporal artery biopsy.

Discussion: Delirium is an acute confusion state with alteration in consciousness, cognition, and attention which is usually caused by an underlying treatable condition. Confounding factors include limited patient history, agitation, and lack of cooperation. GCA is common among the systemic vasculitides and usually targets large and medium-sized arteries, most commonly affecting the aorta, the ophthalmic arteries, and the carotids. Typical symptoms include headache, jaw claudication, temporal tenderness, and vision loss with a female preponderance. Delirium may prove a diagnostic challenge in the elderly. Management of agitated delirium with sedatives may mask some of the clinical findings causing diagnostic delay. Permanent visual loss of one or both eyes may occur secondary to ischemic optic neuropathy in about 20% of patients. Polymyalgia Rheumatica can occur in about 40% of patients. Prompt treatment with steroids before diagnostic temporal biopsy is recommended to avoid complications.

Conclusions: Early diagnosis and prompt treatment with steroids is key to preventing complications of GCA such as blindness. However, GCA has potential to produce mental status change and cortical dysfunction in the elderly population, complicating timely diagnosis. Many questions remain about the underlying pathophysiology; therefore, further research is warranted to help diagnose GCA more accurately and noninvasively.