Acute flaccid myelitis and enterovirus infection: a severe emerging disease

Abstract

Acute flaccid myelitis (AFM) is a neuroinflammatory disease characterized by acute asymmetric weakness of the limbs associated with lesions of the gray matter of the spinal cord. It mainly affects children and has been increasingly identified since 2014. Objective: To describe a severe emerging neurological disease in Chile. Clinical Case: Three children (2 females), previously healthy were included. The age at the onset was between 4 and 6 years. All presented an acute febrile illness associated with upper respiratory symptoms, rapid onset of proximal asymmetric limb weakness, spinal fluid pleocytosis, and enterovirus isolated from nasopharyngeal swab; two patients developed tetraparesis. The MRI of the spinal cord showed T2 hyperintensity of the grey matter. The three patients were admitted to the Pediatric Intensive Care Unit (PICU), and two required mechanical ventilation. No significant improvements were observed after the use of immunomodulatory therapy and plasma exchange. At 12 months of follow-up, one case was quadriplegic and ventilator-dependent; the second died of ventricular arrhythmia in the PICU, and the third one is under rehabilitation with partial recovery. Conclusions: We report the first cases of this severe emerging neurological disease in our country. In a child with predominantly proximal and asymmetric acute limb paralysis, pediatricians must have a high index of suspicion for AFM. Since it can progress rapidly and lead to respiratory failure, suspected AFM should be considered a medical emergency.