Further studies on the treatment of ocular onchocerciasis with diethylcarbamazine and suramin

Abstract

The purpose of the present study was to determine whether or not the elimination of microfilariae by diethylcarbamazine citrate (DEC) would reduce the side effects of a subsequent course of suramin and thus make it more acceptable and safer in the treatment of onchocerciasis. Fifty-four heavily infected patients with ocular onchocerciasis were treated with an initial 2-week course of DEC, in which the dose was increased slowly from 25 mg on the first day to 150 to 200 mg twice daily on days 8 to 14. Betamethasone 1P5 mg was given twice daily 2 days before DEC administration, and during the days of increasing DEC dosage, after which it was tailed off. This course was followed by 3 to 5 weekly injections of suramin. It was found possible to rid these heavily infected patients of most of their microfilariae during the initial course without intolerable side effects. The subsequent suramin course was in general well accepted except in 1 case, where there was a serious aggravation of anterior uveitis. The later development of retinal pigment atrophy in 3 patients, of optic atrophy in 3 others, and of both retinal and optic atrophy in 1 patient is discussed. The effects of this regimen on eye lesions and visual acuity at the final examinations (1 to 4 years) compared favourably with those from our previous trial of suramin given alone or followed by DEC, and they can be summarised as follows: (Table presented).