Challenges in the Clinical Recognition of Acute Flaccid Myelitis and its Implications

Duration of Enterovirus D68 RNA Shedding in the Upper Respiratory Tract and Transmission among Household Contacts, Colorado, USA

“…Cases of AFM are often preceded by a respiratory or febrile illness; median delay is 5–7 days from prodromal respiratory or febrile illness to onset of neurologic symptoms ( 1 , 2 , 27 ). Delayed recognition and misdiagnosis of AFM can result in even further delays in specimen collection and testing, leading to many cases going undiagnosed until weeks to months after symptom onset ( 28 ). Enterovirus PCR detection in sterile sites (e.g., cerebrospinal fluid [CSF] or blood) is specific for the diagnosis of enterovirus neurologic disease, but detection at those sites in AFM is exceedingly rare; enteroviruses are more commonly detected in nonsterile sites, particularly the respiratory tract (EV-D68) and stool (poliovirus, enterovirus A71) ( 29 ).…”

Acute flaccid myelitis in low- to middle-income countries: diagnosis and surveillance

“…In children presenting with acute flaccid paralysis (AFP), it may be difficult to make an aetiological diagnosis at onset, even if all investigations, including imaging and virological tests, are available. 2 , 3 Contrary to poliomyelitis, where the diagnosis can be confirmed by finding poliovirus in a faecal sample of a patient with AFP, the diagnosis of AFM depends on clinical and diagnostic characteristics, as different viruses other than poliovirus may be associated. 4 Early clinical features that may help to differentiate AFM from other causes of AFP in children have been identified ( Table 1 ).…”

“… 4 Early clinical features that may help to differentiate AFM from other causes of AFP in children have been identified ( Table 1 ). 2 , 3 , 5 These include the presence of a sensory level, described in one of the cases by Olum et al ., which would, in our opinion, exclude the diagnosis of AFM. 1 AFM is mainly an anterior horn disease, while a sensory level indicates more diffuse spinal cord involvement, which may be present in other forms of paediatric myelopathies such as neuromyelitis optica and myelin oligodendroglial glycoprotein (MOG) antibody-associated disease or acute vascular injury of the spinal cord.…”

Pediatric acute flaccid myelitis: Evaluation of diagnostic criteria and differentiation from other causes of acute flaccid paralysis

“…Also, in both TM and ADEM longitudinally extensive lesions of the spinal cord on MRI and CSF pleocytosis are commonly found [13,14]. Because of this clinical and diagnostic overlap between AFM and GBS, TM and ADEM, differentiation of these disorders may be particularly difficult, especially early in the disease course [12,[15][16][17].…”

“…Also, associated viruses are best identified early in the disease course, if appropriate sampling is performed [4]. Furthermore, patients with AFM may show rapid clinical deterioration, urging clinical monitoring [17,18]. Lastly, in the mouse model of AFM, early administration of immunoglobulin improved outcome, and administration of monoclonal antibodies against specific strains of EV-D68 was effective in inhibiting progression of muscle weakness even several days after onset [19,20].…”