Interferon alfa combined with azathioprine for the uveitis of Behçet's disease: an open study.

Background: Eye involvement is the main cause of morbidity in Behçet's syndrome. The efficacy of the combined use of azathioprine and interferon alfa in treating this condition has not been studied.

Methods: Ten male BD patients with retinal involvement but no irreversible structural changes were treated with azathioprine 2.5 mg/kg/day and IFN alpha 2b three times weekly for 24 weeks in an open trial. At week 24, IFN alpha was stopped and the patients continued to use azathioprine or received other immunosuppressives as indicated. Clinical response was assessed by visual acuity changes of either eye under the combination treatment and during the follow-up after stopping interferon.

Results: As compared to the study entry, the mean visual acuities of either eye increased significantly at the end of the combination treatment (right eye 5.8 +/- 1.26 vs. 8.3 1.14; P = 0.043; left eye 6.3 1.15 SEM vs. 9.1 +/- 0.9 SEM; P = 0.027). The improvement in visual acuity persisted in the nine patients who were followed for 7.2 +/- 1.6 SEM months after stopping interferon. Reversible hematologic toxicity, mostly in the form of leukopenia, was detected in six patients during the combination treatment.

Conclusions: The combination of IFN alpha and azathioprine appears to be effective for eye involvement of BD. However, the frequent occurrence of myelosuppression mandates close monitoring.