Purpose To report on a case of diffuse unilateral subacute neuroretinitis (DUSN) that was successfully treated with a short course of oral albendazole. Observations A 51-year-old male presented with severe visual loss secondary to DUSN associated with a positive Toxocara serology. Because the parasite could not be detected on fundoscopy, first-line treatment with photocoagulation could not be administered. Treatment with a 6-day course of oral albendazole resulted in the resolution of DUSN as well as the restoration of visual acuity. Conclusion and importance Although DUSN is characterized by the presence of a parasitic organism in the retina, there are cases in which the parasite is not visible. Albendazole has been used to treat such cases, but a standard treatment regimen has not been determined yet. Our case suggests that the resolution of DUSN can be achieved with short-term albendazole therapy.

Purpose: This work presents a case of syphilitic outer retinopathy with findings similar to those of acute zonal occult outer retinopathy (AZOOR). We also discuss the clinical characteristics, treatment, and prognosis of this entity. Methods: A case report and systematic literature review are presented. Results: A 56-year-old woman presented with acute vision loss, localized photopsia, a central scotoma, and retinal findings that were all consistent with AZOOR. A further workup led to a diagnosis of syphilis. Oral prednisone and intravenous penicillin resulted in the resolution of the posterior uveitis and the restoration of visual acuity. However, the central scotoma remained at the 3-year follow-up visit. Conclusions: Syphilitic outer retinopathy is a distinct entity characterized by the disruption of the ellipsoid zone visible on optical coherence tomography and a corresponding increase in fundus hyperautofluorescence in the affected areas. Although some patients may present with a demarcation line, as is seen with AZOOR, the fundus is oftentimes unremarkable or may show only subtle retinal pigment epithelium changes. Uveitis resolution and visual acuity restoration may be expected following treatment; however, visual field disturbances may persist.