Biopsy proven and biopsy negative temporal arteritis: differences in clinical spectrum at the onset of the disease

Objectives-To assess the clinical features of biopsy proven and negative bi opsy temporal arteritis at the time of diagnosis and during a three year fo llow up. Methods-Newly diagnosed cases of giant cell arteritis were included in a pr ospective, multicentre study. Initial clinical and biological features, sea son of diagnosis, and cardiovascular events occurring during the follow up were recorded. Biopsy proven and negative biopsy cases were compared. Results-Two hundred and seven biopsy proven, and 85 negative biopsy cases w ere included from 1991 to 1997. Fifty eight per cent of the biopsy proven c ases, compared with 39.29% of the negative biopsy cases, were diagnosed dur ing the autumn or winter (p = 0.003), Visual problems (31.5%, v 19.1%, p = 0.031), blindness (9.7% v 2.38%, p = 0.033), jaw claudication (40.8%, v 28. 243%, p = 0.044), and temporal artery palpation abnormalities (61.3% v 29.5 %, p = 7.10(-7)) were more frequent in the biopsy proven than in the negati ve biopsy group. Less specific symptoms, such as headache (82.5% v 92.9%, p 0.021), or associated polymyalgia rheumatica (40.1% v 65.9%, p = 9 x 10(-5 )) were more prevalent in the negative biopsy cases. Biological markers of inflammation were significantly more increased in the biopsy proven group. All cases of blindness occurring after treatment belonged to the biopsy pro ven group. Conclusion-Biopsy proven cases seem to be more severe than biopsy negative cases at the time of diagnosis and during follow up. Seasonal difference at diagnosis may suggest a different aetiological pattern.