Giant cell arteritis without clinically evident vascular involvement in a defined population

Objectives. To examine the frequency and clinical presentation of biopsy-proven giant cell arteritis (GCA) patients who do not exhibit overt clinical vascular manifestations. To assess whether differences exist between this group of patients and the rest of biopsy-proven GCA patients. Methods. Retrospective study of biopsy-proven GCA patients diagnosed from 1981 through 2001 at the single hospital for a well-defined population of almost 250,000 people. Patients were considered as having no evident vascular involvement if cranial ischemic manifestations or other vascular complications of GCA were not present at the time of diagnosis or during at least 12 months' followup. Results. Between 1981 and 2001, 210 patients from the Lugo region of northwest Spain were diagnosed with biopsyproven GCA. Eleven patients did not show overt vascular manifestations of GCA. Nine of them presented with polymyalgia rheumatica (PMR) and another 2 fulfilled criteria for fever of unknown origin. Patients without clinically evident vascular involvement had a significantly longer delay to diagnosis than those with vascular manifestations. Also, PMR manifestations were more frequently observed in this group of patients. Conclusions. Biopsy-proven GCA without clinically evident vascular involvement is not exceptional. Despite having a longer delay to diagnosis, these patients constitute a more benign subgroup of GCA.