Vomit as an Alert in a Rare Pathology

Background: Vomits are a frequent symptom in paediatric ages and can be related to severe diseases, like neuromyelitis optica (NMO), characterized by imuno-mediated demyelination and axonal destruction, involving particularly the optic nerve and spinal cord. Anti-aquaporin antibodies (AbAQ4) are involved in the pathogenesis and distinguishes it from multiple sclerosis.

Case Description: Ten year-old boy with irrelevant medical history, with 10 days of recurrent vomiting, food refusal and belching, not responsive to symptomatic treatment. The blood tests and abdominal ultrasound were normal. The upper digestive endoscopy revealed esophagitis, and he started domperidone and pantoprazole, with slight improvement. Seven days after admission he started feeling less active, with frontal headache. The brain MRI showed a lesion at the posterior side of rachidian bulb (postrema area), probably with an inflammatory origin. The CSF revealed pleocytosis (8 cells) with negative virologic, microbiologic and oligoclonal bands. The immunologic study was normal. Vomiting ceased after 5 days of methylprednisolone. Once he stopped the treatment, the vomiting and headache re-emerged, associated with somnolence, dysarthria, blurred vision, vertical nystagmus, unbalance and right hypoesthesia. He restarted corthycoterapy at growing doses. The neuroaxis MRI revealed a new lesion at C3, of inflammatory nature and anti-MOG and AbAQ4 were requested. The patient was transferred to a clinic center with Neuropediatrics, where he initiated plasmapheresis and a course of IV immunoglobulins after the positive result of AbAQ4, with significant improvement. He was readmitted one month later with relapse suspicion, medicated with rituximab. Currently he is under corthycoterapy, asymptomatic and with negative AbAQ4.

Conclusion: The postrema area syndrome is relativity common within NMO and precedes the involvement of the optic nerve or spinal cord, which can be considered an important warning sign. Early recognition and treatment can prevent the occurrence of outbreaks of optic nevritis or transverse myelitis.