Hiccups, Vomiting and the Brain

Introduction: Neuromyelitis Optica (NMO)-spectrum disorders are increasingly recognized in children. Symptomatic brain lesions, usually in the areas of high aquaporin 4 expression, may be the first presenting symptom. Associated autoimmune conditions are observed in approximately 40% of pediatric NMO cases. We present a patient with NMO-spectrum disorder who presented with intractable hiccups and vomiting.

Case report: A 16 year old boy was admitted to our Neurology service with intractable vomiting and hiccups lasting for 10 days. Physical examination revealed sinus bradycardia at 40 bpm, with normal neurological examination. Serum white blood cell count, erythrocyte sedimentation rate, CRP, electrolytes (sodium, potassium, and chloride), glucose, AST, ALT and creatinine were normal. Serum-NMO IgG was positive. Brain MRI revealed a T2 weighted hyperintense lesion in the area postrema without diffusion restriction or enhancement. Intravenous steroid treatment was initiated leading to complete recovery within 24 hours. MRI of the spine and visual evoked potentials were normal. Immunosuppressive treatment was recommended.

Of note, his past medical history included migraine and juvenile myoclonic epilepsy, treated with topiramate and valproic acid respectively. There was no previous history of optic neuritis or transverse myelitis. Three years prior to this presentation he experienced a sinus venous thrombosis. Investigations confirmed three prothrombotic conditions (homozygous for both factor V Leiden and MTHFR mutation, antiphospholipid antibody syndrome), necessitating anticoagulation with coumadin.

Conclusion: Intractable hiccups and vomiting are characteristic for area postrema lesions, an area of high aquaporin 4 expression. The presence of these symptoms in a child already diagnosed with one autoimmune condition was a clue to the diagnosis of NMO-spectrum disorder. Because of the potentially severe prognosis following optic neuritis or transverse myelitis, early diagnosis and initiation of appropriate immunosuppressive treatment is important.

NMO-spectrum disorder - hiccups - aquaporin 4 - area postrema