Research Shows Emerging Need in AFM Prevention & Treatment

The Journal of American Medical Association (JAMA) Pediatrics recently published 3 papers about acute flaccid myelitis (AFM), a polio-like illness in children with outbreaks dating back every other year since 2012, which collectively highlight the still murky understanding of the rare disease and its effects.

“Much still needs to be learned about the cause, progression, biomarkers, prognosis, and treatment of this rare condition,” the journal said in a press release. “So little is known about the prevention or treatment of AMF that researchers are only beginning to understand its cause, which is probably a viral infection by several members from the enterovirus family.”

In the first paper, titled “Acute Flaccid Myelitis—Keys to Diagnosis, Questions About Treatment, and Future Directions,” study authors provided guidance on the recognition of patients with possible AFM and how to initiate a diagnostic evaluation.

They recommended hospital admission when AFM is suspected and suggested the pediatric ICU may be warranted in some cases. They also suggested respiratory monitoring for all patients as well as monitoring for constipation and treatment for neuropathic pain.

“Improved awareness of AFM among physicians is needed to facilitate timely diagnosis and treatment of children with AFM,” study author Matt Elrick, MD, PhD, told Rare Disease Report®. “We also need to advocate for increased attention and funding for the research that will help us to better treat AFM and to stem the tide of this epidemic.”

Dr. Elrick and others also worked on a retrospective case analysis of AFM in a paper titled “Clinical Subpopulations in a Sample of North American Children Diagnosed With Acute Flaccid Myelitis, 2012-2016.” Investigators reviewed the cases of 45 patients diagnosed with AFM under 18 years of age and divided them into groups: Group 1 were American and Canadian patients who met the Center for Disease Control and Prevention (CDC) definition of AFM; and Group 2, which included patients referred to Hopkins with suspected AFM. The team was searching for biologic homogeneity of AFM for inclusion in more research studies.

Dr. Elrick told Rare Disease Report that although the definition of AFM was written to be intentionally broad as not to miss cases, in his study, the team learned that the epidemiologic case definition probably includes patients with alternative diagnoses.

“We were able to write a reliable case description to define the remaining ‘restrictively defined’ AFM cases that might form the basis for inclusion criteria for future research studies,” he said. “This also highlights the challenges in diagnosing AFM in the clinical setting, because it has overlapping features with other causes of paralysis in children.”

Out of the 45 patients who met the CDC AFM case definition, the investigators observed that the mean age of 27 were boys and 37 white patients was 6 years old. There were also 3 Asian patients, 1 Hispanic patient, and 4 mixed-race patients. Of that group, 34 were classified as having restrictively defined AFM, while 11 had alternative diagnosis which included transverse myelitis, other demyelinating syndromes, spinal cord stroke, Guillain-Barre syndrome, Chiari I myelopathy, and meningitis.

Some of the differences between the groups were asymmetry of weakness, lower motor neuron signs, preceding viral syndrome, symptoms evolving over hours to days, absence of sensory deficits, and MRI findings.

Still, a third paper, “A Parental Perspective on Strengthening Knowledge After Acute Flaccid Myelitis,” demonstrated how a private Facebook group for parents navigating their children’s rare AFM could share information, celebrate gains, and grieve together. The study authors read each post in the group, “Parents of Children With Polio-Like Syndrome/Acute Flaccid Myelitis,” which grew to almost 500 members.

In the group, members discussed their fears, which included a period of late summer every other year and periods of hospitalizations, delays in evaluation that could have saved time in diagnosis, and guiding their children’s growth as they grapple with limb-length discrepancies, scoliosis, pain, diplopia, and chronic and dynamic effects of these motor impairments.

The group also addressed the emotional trauma of being dubbed a “disabled person.” Parents leaned on each other, the study authors said, and even shared hand-me-down orthotic devices.

Together, the 3 recent studies emphasize the need for more research and resources in the AFM community, such as timely and accurate diagnoses, prevention, treatments, and coping mechanisms. Moving forward, Dr. Elrick and his colleagues hope to continue filling the gaps that still exist in the AFM population through more research, support, and collaborative efforts.