Positive Temporal Artery Biopsy 6 Months After Prednisone Treatment FREE

Histologic evidence of giant cell arteritis (GCA) may rarely persist despite long-term treatment with doses of corticosteroids adequate to improve symptoms and normalize the erythrocyte sedimentation rate (ESR).^{1 - 3} We describe a patient who had positive findings for GCA on temporal artery biopsy after treatment with prednisone at doses of 30 to 60 mg daily for 6 months. A late biopsy for GCA may be informative, even in the patient treated for months with corticosteroids.

A 71-year-old-woman experienced severe headaches, joint pain, and tenderness of her temporal areas. She had sudden loss of vision in both eyes that was followed by gradual improvement over a few days. The ESR was elevated at 87 mm/h; a presumptive diagnosis of GCA was made, and she was begun on a regimen of prednisone, 60 mg/d, with dramatic improvement in her symptoms. The ESR was 8 and 4 mm/h 1 and 2 months later, respectively, and the prednisone dosage was tapered to 30 mg/d. Approximately 4 months after the onset of symptoms, while on a regimen of 30 mg/d of prednisone and having an ESR of 2 mm/h, she had an uneventful cataract extraction with placement of an intraocular lens implant in the left eye. Her preoperative visual acuities were 20/70 OD and 20/60 OS. Postoperatively, her visual acuity was 20/50 OU. One week after surgery she complained of scalp and temporal area tenderness. Although the ESR was only 5 mm/h, the prednisone dosage was increased to 40 mg/d. Her symptoms abated and the prednisone dosage was tapered to 35 then 30 mg/d over 2-week intervals.

Six months after the initial onset of symptoms, her best-corrected visual acuity was 20/60 OD and 20/25 OS. There was red desaturation in her left eye. There were nuclear sclerotic cataract changes sufficient to account for the decreased visual acuity in her right eye. Her pupils were equal, with a small left relative afferent pupillary defect. The right optic disc was normal and the left showed mild temporal pallor. Kinetic perimetry revealed an inferior altitudinal scotoma on the left and a normal field on the right.

Because of her recurrence of symptoms while taking the 30-mg/d regimen of prednisone when she had a normal ESR, the initial diagnosis of GCA was questioned. Findings from a left temporal artery biopsy revealed a muscular artery with thickened intima. The internal elastic lamina was fragmented and there was granulomatous reaction with multinucleated giant cells centered around the inner elastic lamina. The muscular wall contained a lymphocytic infiltrate. (Figure 1 and Figure 2).

Histologic evidence of GCA may persist despite treatment with corticosteroids. To and colleagues¹ described an 80-year-old woman with GCA who, after 4 weeks of prednisone therapy at 60 mg daily, underwent temporal artery biopsy, the results of which demonstrated active disease. Similarly, a patient treated with chronic low-dose prednisone for polymyalgia rheumatica with recurrent symptoms had positive biopsy findings after 1 month of treatment.² In a series of 535 patients, Achkar et al³ reported positive biopsy findings after 11 months of corticosteroid treatment, but the treatment regimen was not described in detail. In another series, McDonnell and colleagues⁴ distinguished between the histologic features of active and healed arteritis. Both are characterized by marked intimal thickening, disruption or loss of the internal elastic lamina, and thickening and scarring of the media and adventitia. Active arteritis shows an inflammatory infiltration with lymphocytes, macrophages, and multinucleated giant cells, whereas healed arteritis shows only occasional foci of lymphocytes. Temporal artery biopsy specimens with evidence of active arteritis were taken after a mean of 7 days of treatment, whereas those with healed arteritis were taken after a mean of 82 days of therapy.⁴ The longest corticosteroid-to-biopsy interval among patients in this series with active arteritis was 45 days.

To our knowledge, our patient has one of the longest reported intervals of positive biopsy findings after corticosteroid treatment for GCA, and the corticosteroid dosage was substantial. Although early biopsy is always recommended, arteritis may still be histologically documented after several months of a corticosteroid regimen adequate to improve symptoms and normalize the ESR. Positive biopsy findings will help facilitate future decisions on corticosteroid therapy, particularly if complications from such therapy are expected. Recognition of healed vs active arteritis is also vital in cases where the patient has been on a regimen of corticosteroids without the benefit of biopsy. The distinction between active and healed arteritis probably does not carry as much diagnostic as prognostic value, since evidence of active disease despite corticosteroids probably indicates that a longer or more aggressive therapeutic approach is needed.

Supported in part by a departmental grant (Ophthalmology) from Research to Prevent Blindness, Inc, New York, NY, and by CORE grant P30-EY6360 from the National Institutes of Health, Bethesda, Md.

Corresponding author: Nancy J. Newman, MD, Neuro-Ophthalmology Unit, Emory Eye Center, 1365-B Clifton Rd NE, Atlanta, GA 30322 (e-mail: ophtnjn@emory.edu).