Managing Suspected Temporal Arteritis without a Temporal Artery Biopsy
Keith Ong, Ophthalmologist, University of Sydney, RNSH, Ryde Hospital, Dalcross Adventist Hospital
Lawrence Tsng Chze Ong, Immunology Registrar, Westmead Hospital
Lillian Beatrice Ong, JMO, Prince of Wales Hospital
We would like to report 2 cases of suspected temporal arteritis which were managed without routine temporal artery biopsy.
The gold standard diagnostic test for temporal arteritis, the temporal artery biopsy (TAB), is highly specific for a diagnosis of temporal arteritis, but is only positive in up to 82% of temporal arteritis cases (with sensitivities reported as low as 20%). This figure has been shown to decrease even further (12%) following corticosteroid therapy.
Although it is a relatively minor procedure, the risks of TAB are not trivial and include facial nerve injury, infection, haemorrhage, incisional alopecia, scar widening and foreign body reaction to entrapped hairs. Furthermore, the need for theatre time and skilled personnel in a procedure with a significant number of false negatives makes TAB questionable.
Even if TAB were performed, a high index of suspicion would have led to commencement of corticosteroid therapy regardless of the biopsy result. The only drawback in not conducting a TAB appears to be the lack of additional conclusive evidence supporting temporal arteritis.
The two cases presented here illustrate how a trial of corticosteroid therapy is a reasonable and practical option for patients who elect not to have TAB. The strength and duration of corticosteroid therapy will still be guided by clinical progress as well as biochemical markers such as ESR and CRP.