Título

TWO CASES OF DIFFUSE UNILATERAL SUBACUTE NEURORETINITIS (DUSN): FROM EARLY TO ADVANCED STAGE

Objetivo

To report two cases of Diffuse Unilateral Subacute Neuroretinitis (DUSN) in different stages of the disease, highlighting the importance of early diagnosis and effective treatment.

Relato do Caso

Case 1: A 12-year-old boy presented with low visual acuity (LVA) in the right eye. Upon examination by fundoscopy, mild optic nerve edema, diffuse multiple yellow-gray-white lesions were observed in the posterior pole and mid-periphery, accompanied by minimal vitreitis and the hypothesis of DUSN was considered. It was administered albendazole 400mg for 30 days. Anatomic improvement was observed in the healing of lesions associated with hyperpigmentation of the retinal pigment epithelium (RPE), as well as an increase in visual acuity.

Case 2: A 25-year-old patient presented with LVA in the left eye (OS) for over 60 days, with no previous medical or ophthalmological history. Upon examination, some optic nerve edema, increased internal limiting membrane reflex (Oréfice’s sign), diffuse RPE degeneration. A suggestive worm was visualized in the lower quadrant. Treatment with local laser photocoagulation was indicated.

Conclusão

DUSN is a multifocal chorioretinitis caused by a nematode that affects young healthy individuals. The disease presents in a spectrum of stages, with clinical manifestations that include vitreitis, multifocal gray-white outer retinal lesions, and RPE disruption, as well as narrowing of the retinal vessels and optic atrophy. The diagnosis of DUSN is established through the identification of clinical ocular signs accompanied by the presence of an intraocular nematode. Early recognition and diagnosis of DUSN, followed by accurate localization and photocoagulation of the worm can potentially prevent significant visual impairment. However, the visualization of the worm occurs in about 40% of cases once they are very mobile and rapidly shift location. A high level of suspicion for DUSN in young patients with unilateral gradual vision loss presenting signs of posterior uveitis, focal RPE changes and subretinal spots.