61–year–old female with a medical history of asthma, fibromyalgia, hypertension, osteoarthritis, insomnia and anxiety was admitted to the hospital for persistent low–grade fever, cough and myalgias for 12 weeks. Extensive outpatient workup including chest X–ray, CT scan chest and bronchoscopy was negative. Outpatient treatment with prednisone, bronchodilators, cough suppressants, esophageal reflux medications and antibiotics showed no improvement. 2 days before admission, she developed severe throbbing right parietal and temporal headache and blurry vision. She was also complaining of black floaters and flashing lights in visual fields–more in the right eye, right ear pain, jaw pain and throat pain. Laboratory evaluation was notable for white blood cell count 5.3 x 103/mm3, hemoglobin 11.2 g/dL, platelets 335,000, C–reactive protein (CRP) 132 mg/dL and erythrocyte sedimentation rate (ESR) 96 mm/hr. CT scan of chest and paranasal sinuses was unremarkable. PET scan from skull base to mid thigh showed diffusely increased tracer uptake in large arteries supporting the diagnosis of large vessel arteritis. She had a negative temporal artery biopsy. She was started on intravenous solumedrol 250 mg every 6 hours for 3 days. She improved significantly. ESR and CRP were normalized and she was discharged on oral prednisone and outpatient rheumatology follow up.
Giant cell arteritis or temporal arteritis or cranial arteritis is a systemic, inflammatory, vascular syndrome involving medium and large arteries of head and neck. In typical cases, it is characterised by multinucleated giant cells and an infiltrate of plasmocytes, lymphocytes and neutrophils in the artery wall. About half of persons with giant cell arteritis have underlying polymyalgia rheumatica, whereas about 15% of individuals with polymyalgia rheumatica develop giant cell arteritis. The American College of Rheumatology has developed diagnostic criteria for giant cell arteritis. 3 of the 5 criteria must be met to support the diagnosis (Table 1). Patients often have other symptoms such as malaise, fatigue, low–grade fever, anorexia, weight loss, myalgias or arthralgias and visual symptoms, including blurring and scotomas. The onset of these symptoms may be abrupt or insidious. Jaw claudication and pain with chewing are highly specific symptoms of giant cell arteritis and occur in nearly 50% of patients. Important lab finding is elevated acute phase reactants (ESR and CRP). Imaging studies include MRI/MRA of aortic branch, color duplex USG of the temporal arteries and PET scan. Temporal artery biopsy is the gold standard for diagnosis although it is not needed for diagnosis and is not always positive.
In the face of strong clinical suspicion, negative temporal artery biopsy does not completely rule out the diagnosis of giant cell arteritis. Risk of permanent visual loss from giant cell arteritis necessitates urgent evaluation and implementation of treatment.
Table 1American College of Rheumatology diagnostic criteria for giant cell arteritis
|Age more than or equal to 50 years|
|New onset localized headache|
|Temporal artery tenderness or decreased pulse|
|ESR atleast 50 mm/hr|
|Abnormal artery biopsy|
|3 of the 5 criteria must be met to support the diagnosis.|