Iron deficiency masquerading as idiopathic intracranial hypertension.

A 13-year-old female presented with complaints of headache, vomiting, diplopia and progressive blurring of vision developing sequentially over 1 month. Examination revealed marked pallor and bilateral lateral rectus palsy with a visual acuity of 6/12 and 6/36 in the left and the right eye, respectively. Fundus examination showed late stage papilloedema in both eyes. Investigation for anaemia revealed severe iron deficiency. MRI of the brain was normal. The cerebrospinal fluid opening pressure was markedly raised at 320 mm of water but fluid analysis did not reveal any abnormality. Thus, a diagnosis of iron deficiency anaemia with idiopathic intracranial hypertension was made. The patient responded dramatically to intravenous iron treatment. Physicians must be aware of this rare presentation of the common problem of iron deficiency, the rapid correction of which plays an instrumental role in salvaging the patient's vision and preventing a recurrence of disease.