Autoimmune retinopathy and optic neuropathy associated with enolase-positive renal oncocytoma

Abstract

Purpose: To report a case of autoimmune retinopathy and optic neuropathy associated with an enolase-positive renal oncocytoma.

Observations: A 41-year-old man presented with subacute, painless, bilateral vision loss. On initial examination, visual acuity measured 20/125 OD and 20/1250 OS, and telangiectatic vessels were noted on the optic nerves and in the maculae. Goldmann perimetry showed bilateral, cecocentral scotomas, and electroretinography demonstrated reduced photopic and scotopic signals, concerning for autoimmune retinopathy. Serum testing showed multiple positive anti-optic nerve and anti-retinal antibodies, including to alpha-enolase. Extensive systemic workup was negative except for a large, exophytic, right renal mass. Biopsy was consistent with a benign oncocytoma, and immunohistochemical staining showed diffusely positive alpha-enolase staining. The patient was treated with a five-day course of intravenous methylprednisolone and plasmapheresis with minimal improvement. Surgical excision of the oncocytoma was performed. At 9-months post-operatively, visual acuity had improved to 20/40 OU, with corresponding improvement on visual field and electroretinography testing.

Conclusions and importance: To our knowledge, this is the first report of autoimmune retinopathy and optic neuropathy associated with a renal oncocytoma. The case highlights the importance of a thorough systemic workup in cases of suspected autoimmune retinopathy and reminds clinicians that even tumors considered benign can have distal effects on other organs.

Keywords: Autoimmune retinopathy; Oncocytoma; Optic neuropathy.

Fig. 1

Goldmann visual fields at presentation and 12 month follow-up, both eyes. Goldmann visual field of the right eye at presentation (A) demonstrates complete loss of the I2e isopter (red), with 25° cecocentral scotoma of the I4e isopter (blue) and 20° cecocentral scotoma of the V4e isopter (magenta). On follow-up (C), there was return of the I2e with decrease in the size of the I4e and V4e scotomas to 15 and 5°, respectively. The left eye at presentation (B) also had complete loss of the I2e isopter, with 30° cecocentral scotoma of the I4e isopter and 20° cecocentral scotoma of the V4e isopter. On follow-up (D), there was return of the I2e with decrease in size of the I4e scotoma to 5° and complete resolution of the V4e scotoma. (For interpretation of the references to colour in this figure legend, the reader is referred to the Web version of this article.)

Fig. 2

Color fundus photographs at presentation and 12 month follow-up, both eyes. Fundus photographs of the right (A) and left (B) eyes at presentation demonstrate optic nerve head hyperemia with telangiectatic vessels on the optic nerve and in the macula. Follow-up imaging of the right (C) and left (D) eyes demonstrates optic nerve pallor and resolved telangiectasias in both eyes. (For interpretation of the references to colour in this figure legend, the reader is referred to the Web version of this article.)

Fig. 3

Optical coherence tomography at presentation and 12 month follow-up, both eyes. Optical coherence tomography of the right (A) and left (B) eyes at presentation demonstrates saw-tooth outer plexiform layer irregularities that are less prominent on follow-up (C and D). There is retinal thinning in both eyes with qualitative thinning of the retinal nerve fiber and ganglion cell layers (C and D).

Fig. 4

Electroretinography at presentation and 10 month follow-up. Electroretinography at presentation shows reduced cone and rod responses, with decreased amplitudes and delayed latencies, suggesting cone greater than rod dysfunction in both eyes. On follow-up, dark adapted (rod response) amplitudes are low normal, with overall improved b-wave amplitudes and latencies (best seen in the combined and cone responses).

Fig. 5

Computed tomography imaging and immunohistochemical analysis. (A) Positron emission tomography-computed tomography (PET-CT) shows intensively hypermetabolic uptake by the right renal mass (arrow), without other lesions. (B) Immunohistochemical staining of the renal oncocytoma shows positive alpha-enolase staining (yellow) throughout the biopsy sample. (For interpretation of the references to colour in this figure legend, the reader is referred to the Web version of this article.)