J Korean Med Sci.  2015 Mar;30(3):346-349. 10.3346/jkms.2015.30.3.346.

Diffuse Unilateral Subacute Neuroretinitis in a Healthy Korean Male: The First Case Report in Korea

• Kang HM
• Lee CS

• KMID: 2133316
• DOI: http://doi.org/10.3346/jkms.2015.30.3.346

Abstract

A 52-yr-old male was referred for progressive visual loss in the left eye. The decimal best-corrected visual acuity (BCVA) was 0.01. Fundus examination revealed diffuse retinal pigment epithelial degeneration, focal yellow-white, infiltrative subretinal lesion with fuzzy border and a live nematode within the retina. Diffuse unilateral subacute neuroretinitis (DUSN) was diagnosed and the direct laser photocoagulation was performed to destroy the live nematode. During eight months after treatment, BCVA gradually improved to 0.2 along with the gradual restoration of outer retinal layers on SD-OCT. We report on the first case of DUSN in Korea. DUSN should be included in the differential diagnosis of unexplained unilateral visual loss in otherwise healthy subjects.

Keyword

Diffuse Unilateral Subacute Neuroretinitis; Zoonosis; Nematode; Laser Photocoagulation

MeSH Terms

Animals
Blindness/diagnosis/parasitology
Eye Infections, Parasitic/diagnosis/parasitology/*therapy
Fundus Oculi
Humans
Laser Therapy/methods
Light Coagulation/methods
Male
Middle Aged
Nematoda/*pathogenicity
Republic of Korea
Retinal Pigment Epithelium/*parasitology/pathology
Retinitis/diagnosis/*parasitology/*therapy
Visual Acuity

Figure

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  Fig. 1 Representative figures of the first Korean case with diffuse unilateral subacute neuroretinitis. A 52-yr-old male patient was referred to the tertiary ophthalmology clinic for gradual deterioration of vision in the left eye for the past 10 days. The best-corrected visual acuity (BCVA) in the left eye was 0.01 according to the decimal visual acuity chart. (A) Fundus of the left eye shows a yellow-white, infiltrative subretinal lesion with a whitish nematode (arrow) inferotemporal to the fovea. (B) Spectral domain optical coherence tomography (SD-OCT) of the left eye shows fluid accumulation in the epiretinal space of the fovea (asterisk), with diffuse disruption of external limiting membrane (ELM) and photoreceptor layer at fovea. (C) Cross-section SD-OCT image of a nematode beneath the internal limiting membrane (ILM). Under the diagnosis of diffuse unilateral subacute neuroretinitis, direct laser photocoagulation was done to eliminate the nematode. (D) After two weeks, infiltrative lesion was resolved. Note the pigmented area due to direct laser photocoagulation. (E) SD-OCT shows complete resolution of fluid at sub-ILM space and recovery of ELM. However, photoreceptor layer was not fully recovered. (F) At an 8-month follow-up visit, the BCVA of the left eye improved as 0.2. Diffuse disruption of photoreceptor disruption on SD-OCT was much recovered.

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