Cytotoxic drugs in ocular lesions of Behçet's disease

Introduction

Cytotoxic drugs are the first line treatment for ophthalmologic manifestations of Behçet's disease (BD) despite the advent of the new biological agents. The latter are to be used in intractable inflammatory attacks as they seem to be efficient in a few case studies. Cytotoxic drugs are affordable, easy to use, effective and safe, even in long-term use. They have to be combined to steroids (0.5 mg prednisolone/kg per day as attack dose, then tapering gradually to the patient's need). All the cytotoxic drugs used were effective (ACR 1966, APLAR 2000).

As all treatment methods with cytotoxic drugs were efficient and had approximately the same efficiency (percentage of eyes with improved VA), all data were pulled together. The advantage to put the data together was to show the result of treatment in long run in real life. Some patients who were resistant to the given treatment were switched to another treatment and if again ineffective to a third or forth treatment. In pulled data the results before the first treatment were compared with those after the last treatment.

Materials and methods

Patients who had an active posterior uveitis and/or retinal vasculitis were selected for this study. They were 978 patients. Among them, 277 received more than one treatment. The mean duration of eye lesions was 54 months (SD 42.1), with the maximum duration 271 months. The mean follow-up time was 52 months (SD 40.8) with the maximum of follow up 261 months. Comparison was made by the Student paired t test. VA was calculated on a Snellen chart on a scale of 10 on 10. The Activity Indexes (AI) for different compartment of eyes were calculated according to Ben Ezra.

Results

The mean VA of all eyes was 3.8. It improved to 4.7 after the treatment (t 9.544, P < 0.000001). Improved eyes were 52%, 18% were unchanged, and 30% were aggravated. The mean AI of anterior uveitis improved from 2.5 to 0.8 (t 18.595, P < 0.000001). Improved eyes were 77%, 4% were unchanged, and 19% were aggravated. The mean AI of posterior uveitis improved from 2.1 to 0.9 (t 27.039, P < 0.000001). Improved eyes were 74%, 10% were unchanged, and 16% were aggravated. The mean AI of retinal vasculitis improved from 2.5 to 1.4 (t 11.661, P < 0.000001). Improved eyes were 62%, 12% were unchanged, and 26% were aggravated.

To see if the cytotoxic drugs maintained their efficacy over the time, patients were divided in different groups according to their treatment duration. The percentage of improved eyes remained the same, even in the group of patients where the duration of treatment exceeded 9 years.

Conclusion

The least improved parameter was the visual acuity, which reflects not only the inflammatory index of the eye, but also the chronicity index (cataract, vitreous organization, hemorrhage, vessel necrosis of retina, neovascularization, and optic nerve atrophy). Seventy percent of the eyes improved or maintained their VA, which is quite remarkable for this disease.