538 Neurorétinite subaiguë unilatérale diffuse : à propos de 2 cas

Abstract

Introduction Diffuse Unilateral Subacute Neuroretinitis (DUSN) is an ocular infectious disease caused by a motile nematode, leading to inflammation and degeneration of the outer retina. This affection has already been reported in literature from Brazil, Venezuela, USA, Canada, Caribbean, Spain, Germany, Ghana, India, and we describe here two cases from UK. Aim and Methods Two healthy women, frequent travellers, presented with unilateral reduction in vision respectively from 6/6 to 6/18 and from 6/6 to 6/24, with clusters of yellow-whitish sub-retinal pigment epithelial lesions fading and reappearing in other location of the fundus, after days to weeks. Based on the clinical picture the diagnosis of DUSN was established. After several unfruitful tentatives of localising the worm by slit lamp examination with a fundus lens, both patients were prescribed with an antihelminthic treatment, albendazole 400 mg daily for 30 days. Observation Improvements of the visual acuity to 6/6 as well as complete resolution of fundoscopic lesions were observed in both of them. The visual acuity was maintained and no new lesions were observed, respectively, over a period of follow up of 12 and 8 months. Visual field defects were unchanged. Discussion This condition can affect children or young adults, with no gender predilection or systemic association. The eye is affected in such an insidious manner, that in most of cases patients realize their visual loss only towards the late stage of the disease. The appearance followed by the disappearance of creamy lesions within days to weeks concomitantly with the development of new clusters of lesions elsewhere in the fundus, even without any worm seen, is highly suspicious of the diagnosis of DUSN. Therefore it is important to review the patient as often as needed when this condition is suspected. Even though laser photocoagulation of the worm is the best way to eradicate the problem, this is not always possible since the worm is found in 40% of the cases only. In such cases oral albendazole seems to be a safe and valuable treatment. Conclusion DUSN is a sight threatening disease. Preservation of the visual acuity relies on an early diagnosis and treatment.