Disease pattern in cranial and large-vessel giant cell arteritis

Objective. To identify variables that distinguish large-vessel giant cell a rteritis (GCA) with subclavian/ axillary/brachial artery involvement from c ranial GCA. Methods. Seventy-four case patients with subclavian/axillary GCA diagnosed by angiography and 74 control patients with temporal artery biopsy-proven G CA without large vessel involvement matched for the date of first diagnosis were identified. Pertinent initial symptoms, time delay until diagnosis, a nd clinical symptoms, as well as clinical and laboratory findings at the ti me of diagnosis, were recorded by retrospective chart review. Expression of cytokine messenger RNA in temporal artery tissue from patients,vith large- vessel and cranial GCA was determined by semiquantitative polymerase chain reaction analysis. Distribution of disease-associated HLA-DRB1 alleles in p atients with aortic arch syndrome and cranial GCA was assessed. Results. The clinical presentation distinguished patients with large-vessel GCA from those with classic cranial GCA. Upper extremity vascular insuffic iency dominated the clinical presentation of patients with large-vessel GCA , whereas symptoms related to impaired cranial blood flow were infrequent. Temporal artery biopsy findings were negative in 42% of patients with large -vessel GCA. Polymyalgia rheumatica occurred with similar frequency in both patient groups. Large-vessel GCA was associated with higher concentrations of interleukin-2 gene transcripts in arterial tissue and overrepresentatio n of the HLA-DRB1*'0404 allele, indicating differences in pathogenetic mech anisms. Conclusion. GCA is not a single entity but includes several variants of dis ease. Large-vessel GCA produces a distinct spectrum of clinical manifestati ons and often occurs without involvement of the cranial arteries. Large-ves sel GCA requires a different approach to the diagnosis and probably also to treatment.