Myelin oligodendrocyte glycoprotein antibody-associated disease with aseptic meningitis-like presentation in a paediatric patient.

In the paediatric population, myelin oligodendrocyte glycoprotein antibody-associated disease (MOGAD) phenotypes continue to be identified. We present a case of seropositive MOGAD that began as what appeared to be aseptic meningitis with elevated intracranial pressure, followed by inflammatory myelopathy. The paediatric patient presented with a four-day history of persistent frontal headache, vomiting and episodic confusion without a fever. Lumbar puncture showed elevated cerebrospinal fluid opening pressure and lymphocytic pleocytosis. Her headaches worsened despite treatment for increased pressure with acetazolamide. Her symptoms of inflammatory myelopathy emerged four days after admission. MRI brain at presentation demonstrated bilateral narrowing of the transverse sinuses as seen with idiopathic intracranial hypertension (IIH). After development of urinary retention and lower extremity symptoms, MRI spine showed signal abnormalities within the grey and white matter of both the cervical and thoracic spinal cord consistent with an inflammatory myelopathy. Serum MOG antibodies were positive. Here, we present a case of MOGAD that began with an aseptic meningitis-like presentation, but without the more commonly described initial presentations of MOGAD to illustrate an emerging phenotype. Aseptic meningitis with imaging suggestive of IIH, as well as persistent or evolving symptoms in a paediatric patient, should raise suspicions for MOGAD and prompt MOG antibody testing.