Diffuse unilateral subacute neuroretinitis.

Diffuse unilateral subacute neuroretinitis (DUSN) is a usually unilateral inflammatory disease characterized by an insidious, usually severe loss of peripheral and central vision. Clinical characteristics are manifested in early and late stages. Parasites of different sizes and several species of nematodes have been reported as the etiology of DUSN without conclusive evidence about the specific agent. Because serologic testing has been variable, the definitive diagnosis is made when the clinical characteristics of DUSN are found in conjunction with an intraocular worm. Laser photocoagulation, pars plana vitrectomy, thiabendazole, and albendazole have been used to treat DUSN with variable success.