Giant cell arteritis.

An 80-year-old woman was admitted after a 4 months history of severe headache. Laboratory data revealed elevated ESR, mild anemia and alteration of liver function test. Temporal artery biopsy showed the classical picture of giant cell arteritis. The clinical symptoms and laboratory abnormalities reversed to normal after prednisolone therapy. Although the true prevalence of this disease is unknown in Thailand, previous studies in western countries have revealed that it is not a common disease. GCA may be missed or incorrectly diagnosed in elderly patients with headache and a high ESR. Such a diagnosis can subject the patient to complication of GCA, needless biopsy and serious side effects of therapy with large doses of prednisolone.