Sir,

Arteritis affecting the temporal arteries may be the initial presentation of a widespread systemic vasculitis affecting multiple organ systems and requiring immunosuppressants other than corticosteroids to induce remission.

Case report

A 59-year-old woman presented to the eye department with a 1-day history of sudden decline in vision in the left eye. Associated symptoms were a 1-month history of intermittent frontal headache, jaw claudication, weight loss, and ‘lumpy’ areas on her temples. Best-corrected visual acuity was Snellen 6/6 right eye and 6/36 left eye. On examination, the left optic nerve head was swollen and the left temporal artery was tender and non-pulsatile. ESR was >100 mm/h and CRP was 195 mg/l. A diagnosis of temporal arteritis was made and corticosteroid treatment commenced.

Subsequently, a temporal artery biopsy confirmed arteritis but with features atypical for giant cell arteritis, namely a predominantly eosinophilic infiltrate (Figure 1a), a paucity of giant cells and fibrinoid necrosis (Figure 1b). Because of these features, she was referred to a rheumatologist. Further investigation revealed peripheral nerve involvement, livido reticularis, mild renal impairment (creatinine 102 μmol/l), and positive pANCA anti-MPO antibodies. A diagnosis of microscopic polyangiitis was made by the rheumatologist, who subsequently took over management. Combined treatment with corticosteroids and cyclophosphamide was commenced to induce remission.

Figure 1
figure 1

Haematoxylin- and eosin-stained sections of temporal artery biopsy. (a) Inflammatory infiltrate of temporal artery, including many eosinophils (arrows). (b) Area of fibrinoid necrosis in temporal artery (arrowhead).

Full size image

Comment

It is common for the ophthalmologist to be referred suspected cases of temporal arteritis. It is also common for patients to be treated presumptively with corticosteroids on the basis of a raised ESR and symptoms alone. Published good rheumatologic practice for the management of vasculitis advocates biopsy of affected tissue to classify the vasculitis and choose a treatment regimen.1 The often quoted American College of Rheumatology diagnostic criteria for temporal arteritis have a false-positive rate of 7.8%.2 We suggest that patients with the clinical diagnosis of temporal arteritis should undergo temporal artery biopsy to confirm the histological diagnosis of giant cell arteritis. If the biopsy shows atypical features, they should undergo investigation into the possibility of systemic vasculitis, which ideally should be undertaken by a rheumatologist. There have been other reports of ANCA-associated small vessel vasculitis affecting larger vessels.3, 4, 5 In our case without the biopsy findings, the presence of systemic vasculitis with renal impairment could have been missed and the treatment regimen would have been inadequate to induce remission.