A 32-year-old female of Egyptian origin presented with a 2-week history of decreased vision in the left eye. There was no past history of eye problems, injury, or previous eye surgery. She was under the care of a neurologist with a 2-year history of IgG4 systemic fibrosclerosis with mediastinal involvement. A chest X-ray taken after a nonresolving chest infection revealed a pulmonary infiltrate and the patient underwent thoracotomy and biopsy of the lesion. The diagnosis of IgG4-related disease was confirmed histologically. IgG4 serum level was elevated at 410 mg/dL. Inflammatory markers demonstrated a raised erythrocyte sedimentation rate. She had also completed empirical tuberculosis treatment. Her past medical history included epilepsy, chronic migrainous headache, low mood, lumbosacral back pain secondary to intervertebral disc protrusion at the level of L5/S1, and disturbed sleep with episodic sleep paralysis with possible restless leg syndrome. She had been consuming 75 mg of Topamax  (topiramate) for 12 months on the advice of her neurologist and had previously been prescribed azathioprine and rituximab. Current treatment included pregabalin, duloxetine, and oral prednisolone with alendronic acid weekly, and calcichew and lansoprazole daily. The presenting best corrected vision was 6/6 in the right eye and vision of 6/9 in the left eye. Clinical examination showed bilateral anterior uveitis with bilateral cystoid macular edema. Intraocular pressures were within normal limits with deep anterior chambers. Pupils were equal and reactive with no relative afferent pupillary defect. Color vision was decreased in the left eye. Dilated fundal examination revealed cystoid macula edema, optic discs were normal, and retinal vasculature was normal. No vitritis was present. Magnetic resonance imaging showed normal intracranial and orbital appearances. Systemic workup demonstrated increased levels of inflammatory markers: erythrocyte sedimentation rate and C reactive protein. Antinuclear antibody, rheumatoid factor, anti-neutrophil cytoplasmic antibody, angiotensin converting enzyme, and syphilis testing were negative.
The patient was initially treated with dexamethasone 0.1% qds to both eyes. Vision subsequently deteriorated to 6/13 in the right eye and 6/38 in the left eye over the next few weeks. Spectral domain optical coherence tomography (OCT) (Cirrus, Carl Zeiss Meditec, Dublin, CA, USA) revealed bilateral intraretinal fluid cysts. Fundus fluoroscein and indocynanine green angiography showed no vasculitis or vascular leakage at the macula. The patient was known to be a long-standing myopic with a refraction of -8.00 D sphere bilaterally. Goldmann visual field testing showed bilateral central scotomas.
Electrodiagnostic testing showed normal bilateral pattern and flash visually evoked potentials. Pattern electroretinograms (ERGs) were moderately subnormal in both eyes. Multifocal ERGs showed reduced bilateral responses. The findings suggested bilateral central macular dysfunction, with no electrophysiological evidence of generalized retinal dysfunction or optic nerve dysfunction. The findings were consistent with bilateral macular edema (Figure 1).
After neurology consultation, the patient was advised to stop taking topiramate and subsequently OCT macular changes were completely resolved (Figure 2).
Due to weight gain after cessation of therapy, the patient recommenced topiramate treatment with recurrence of maculopathy. Vision decreased to 6/24 on the right and 6/19 on the left over a 6-month period. She was advised again to cease topiramate and subsequently macular changes resolved completely.
The resolution of the symptoms and macular signs in this patient after cessation of therapy strongly suggest that topiramate was the relevant etiological factor. This patient's maculopathy was reversible on cessation of topiramate.
The patient provided written consent for publication. The patient was not enrolled in a clinical trial and did not receive any experimental treatment, hence ethical approval was not sought from the institutional review board.