Pseudo-Foster Kennedy Syndrome as a Rare Presentation of Vitamin B12 Deficiency.
BACKGROUND
Pseudo-Foster Kennedy syndrome is a triad consisting of ipsilateral optic atrophy, contralateral optic disc edema, and ipsilateral anosmia in the absence of an intracranial mass. Vitamin B12 plays an important role in DNA synthesis, and its deficiency causes peripheral neuropathy, myeloneuropathy, and, very rarely, optic neuropathy.


METHODS
In this study, we describe a 34-year-old male who presented with progressive loss of visual acuity and field. Fundoscopy showed optic disc edema with telangiectasia in the right eye, while the left eye had optic disc atrophy. We ruled out nearly all possible and common causes of optic neuropathy, and vitamin B12 deficiency was finally diagnosed. After treatment with vitamin B12, the patient improved.


CONCLUSIONS
Demyelinating disease, anterior ischemic optic neuropathy, non-arteritic anterior ischemic optic neuropathy, autoimmune disease, and hereditary optic neuropathy could cause optic neuropathy. Normal CBC parameters and the absence of clinical manifestations of vitamin B12 deficiency could not rule out its diagnosis. Careful physical examinations and history-taking with a classical approach led us to the diagnosis of vitamin B12 deficiency and its treatment.
Department of Neurology, School of Medicine, Shiraz University of Medical Sciences, Shiraz, IR Iran.
Peyman
P
Petramfar
Student Research Committee, Shiraz University of Medical Sciences, Shiraz, IR Iran.
Farideh
F
Hosseinzadeh
Student Research Committee, Shiraz University of Medical Sciences, Shiraz, IR Iran.
S Saeed
SS
Mohammadi
Foster-Kennedy Syndrome; Optic Nerve Disease; Optic Neuritis; Optic Neuropathy; Papilledema; Vitamin B12 Deficiency