RESUMO
A previously healthy 6-year-old boy was admitted to hospital with hypotonia and hyposthenia of lower limbs. Electromyography and slow motor nerve conduction velocity test identified a lower limb acute motor axonal neuropathy. Brain and spinal cord magnetic resonance imaging demonstrated multifocal cortical gray matter lesions in both cerebral hemispheres consistent with gray matter acute disseminated encephalitis otherwise with viral/Mycoplasma pneumoniae encephalitis, and signs of involvement of anterior nerve roots of the cauda equina consistent with Guillain-Barré syndrome. The patient resulted negative to routinely bacterial and viral investigations but positive to human parechovirus that sequence analyses confirmed as type 6. Intravenous immunoglobulins and methylprednisolone treatment were administered but did not relieve the symptoms of Guillain-Barré syndrome. The disease improved gradually over the next 3-month follow-up with a complete remission of both central and peripheral nervous system symptoms.