Giant cell arteritis

us of the variability in presentation of giant cell arteritis (GCA).1 Another pa-tient’s story presents yet another pitfall in GCA diagnosis. A 76-year-old woman presented to the emergency department with right temporal “head pain. ” Her erythrocyte sedimentation rate was 65 mm/h. The diagnosis was “headache, rule out tem-poral arteritis. ” Prednisone, 40 mg per day, was prescribed, and the patient was referred for follow-up examina-tion. Four days later, the patient’s ten-derness to percussion over the right temporal area persisted, and I in-creased the prednisone dosage. A biopsy was performed 2 days later. The biopsy results, available 1 week later, showed no evidence of GCA, so the ophthalmologic surgeon stopped the patient’s prednisone. The patient returned to me 4 days later with in-creasing “head pain. ” We discussed the possibility of false-negative biopsy findings, and I prescribed prednisone again (and osteoporosis prophylaxis). A consultation was arranged with a rheumatologist who concurred with the diagnosis of biopsy-negative CGA and continued to treat the patient ac-cordingly. Although the only confirmatory test for GCA is a positive biopsy, nondiag-nostic biopsy specimens do not exclude the diagnosis. It is commonly accepted that, because of the patchy involvement of the arteries, biopsies may be nondi-agnostic in many patients. Thus, be-cause biopsies are invasive, some au-thors even suggest that biopsy may not be necessary.2,3 Furthermore, corticosteroid ther-apy, which should be started without delay, rapidly reduces the chance of a positive biopsy result.2 One week of corticosteroid treatment may reduce the chance of obtaining a positive biopsy to 10%.4 Therefore, biopsy should be performed within the first few days of therapy.