Enterovirus D68

Centers for Disease Control and Prevention Case Definitions for Acute Flaccid Myelitis[39]Centers for Disease Control and Prevention. Acute flaccid myelitis (AFM): case definitions for AFM. Jun 2024 [internet publication]. https://www.cdc.gov/acute-flaccid-myelitis/php/reporting-patient/case-definitions.html

To be considered a confirmed case of acute flaccid myelitis, a patient must meet the following criteria:

• Illness with acute onset of flaccid weakness of one or more limbs in the absence of a clear alternative diagnosis attributable to a nationally notifiable condition, and

• Confirmatory laboratory/imaging evidence: magnetic resonance imaging (MRI) showing a spinal cord lesion with predominantly gray matter involvement and spanning one or more vertebral segments (excluding gray matter lesions resulting from physician diagnosed malignancy, vascular disease, or anatomic abnormalities).

Acute flaccid myelitis is also confirmed when autopsy findings include histopathologic evidence of inflammation largely involving the anterior horn of the spinal cord spanning one or more vertebral segments.

To be considered a probable case of acute flaccid myelitis, a patient must meet the following criteria:

• Illness with acute onset of flaccid weakness of one or more limbs in the absence of a clear alternative diagnosis attributable to a nationally notifiable condition, and

• Presumptive laboratory/imaging evidence: MRI showing a spinal cord lesion in at least some gray matter, though predominance cannot be determined (excluding gray matter lesions resulting from physician diagnosed malignancy, vascular disease, or anatomic abnormalities).