A "Negative" Temporal Artery Biopsy, Positive for Arteritis

Ophthalmologists often participate in the diagnosis and treatment ofpatients with giant cell arteritis (GCA), typically when the diagnosis isheralded by a central retinal artery occlusion or ischemic optic neuropathy.However, even in the absence of eye symptoms or signs, ophthalmologists maybe asked to examine the patient and perform a biopsy of the temporal artery.The microscopic findings in the patient described herein bear on the techniqueof temporal artery biopsy.

A previously healthy 81-year-old woman developed mandibular pain withchewing, low-grade fevers, night sweats, and proximal limb mylagias. She deniedheadache or visual changes. There were no abnormalities on results of physicalexamination, and her temporal arteries were pulsatile and neither induratednor tender. A chest radiograph was unremarkable. The only abnormality on routinelaboratory testing was microscopic hematuria. Her condition did not improveafter a trial of antibiotics for the presumed diagnosis of sinusitis. Threeweeks after onset of symptoms, an erythrocyte sedimentation rate of 131 mm/hand a C-reactive protein level of 7.9 mg/dL prompted referral for neuro-ophthalmicconsultation and biopsy. Although no abnormalities were found on the examinationresults, we performed a biopsy of the left temporal artery.

The biopsy specimen was fixed and serially sectioned. Microscopic examination(Figure 1) showed a normal temporalartery in all sections, but several small adjacent arteries included in thebiopsy specimen showed granulomatous angiitis.

The patient's symptoms improved with oral prednisone therapy, but furtherinvestigations prompted by persistent hematuria resulted in the diagnosisof Wegener granulomatosis.

As demonstrated by this case, symptoms, signs, and even histologic findingsclassically associated with GCA can be found with other systemic vasculitides.Features attributed to GCA, such as jaw claudication, amaurosis fugax, andan erythrocyte sedimentation rate greater than 100 mm/h, have been seen inpatients with Wegener granulomatosis.^1-3 Likepatients with GCA, patients with Wegener granulomatosis can improve with corticosteroidtreatment, at least initially. However, patients with Wegener granulomatosiswho are misdiagnosed as having GCA and who are treated only with corticosteroidsmay develop acute renal failure and respiratory tract disease.⁴ Whenfaced with a "positive" temporal artery biopsy, the physician must alwaysconsider a diagnosis of a systemic vasculitis other than GCA, as the patientmay experience a fulminant and downhill course if appropriate therapy is notinstituted.

From personal experience with a patient whose diagnosis of GCA was establishedfrom angiitis in small vessels adjacent to a normal temporal artery, one ofus (S.L.) routinely includes the periarterial tissue in temporal artery biopsyspecimens. Had this tissue been stripped from the specimen in our patient,the biopsy would have been interpreted as negative. Temporal artery biopsyspecimens from other patients with Wegener granulomatosis have also shownonly small-vessel involvement.^1-3 Whena temporal artery biopsy is performed, the surgeon should refrain from removingthe periarterial tissues except to the extent necessary to ensure accurateidentification and secure ligation of the vessel. Nor should the pathologiststrip the artery before embedding.

Correspondence: Dr Lessell, Department of Ophthalmology, MassachusettsEye and Ear Infirmary, 243 Charles St, Ninth Floor, Boston, MA 02114 (simmons_lessell@meei.harvard.edu).