Notes from the Field: Cluster of Acute Flaccid Myelitis in Five Pediatric Patients — Maricopa County, Arizona, 2016

Comparative quantitative clinical, neuroimaging, and functional profiles in children with acute flaccid myelitis at acute and convalescent stages of disease

“…The majority of our patients presented in 2016 and throughout the USA, making this the largest detailed report of the 2016 epidemic and the most geographically diverse. [16][17][18] Our patients primarily had parainfectious, hyperacute onset of limb paralysis, associated with a lower motor neuron exam that spared sensory tracts, inflammatory changes in the CSF, and extensive T2-weighted hyperintensity throughout the spinal cord grey matter by neuroimaging. This constellation of features is consistent with what was described in the prior 2014 Colorado and California cohorts, 2,19 and most recently in the 2015 series from Japan.…”

“…IQR, interquartile range; ADHD, and convalesence are depicted in Figure 4. MRC-sum scores increased in eight patients, indicating increased strength, with a median individual change of 18 (IQR [11][12][13][14][15][16][17][18][19][20][21][22]. Overall, the MRC-sum score rose from a median of 29 (IQR 17-38) to 32 (IQR .…”

“…Muscle groups assessed by the Medical Research Council (MRC) score were represented for all 16 patients in which muscle strength was graded from 0 (red, equivalent to paralysis) to 5 (green, equivalent to normal strength). Patients were numbered sequentially based on severity of weakness from highest MRC-sum score of all muscle groups to lowest (left to right,[1][2][3][4][5][6][7][8][9][10][11][12][13][14][15][16]. During the acute stage, neurological examination at nadir of initial hospitalization is depicted.…”

A ten-year retrospective evaluation of acute flaccid myelitis at 5 pediatric centers in the United States, 2005–2014

“…Continued U.S. surveillance under a standardized AFM case definition demonstrated much lower case numbers reported in 2015 and 2017, and increases in 2016 and 2018 with a seasonal peak of cases remarkably similar to 2014 [9][10][11]. To understand the occurrence and features of AFM in the recent past, which would inform investigations on causes of this potentially emerging condition, we performed a retrospective evaluation of AFM cases in different U.S. regions over a 10-year period.…”

Changing how we think about infectious diseases

“…Side-stepping Koch's postulates has become de rigueur in the practice of modern medicine. For example, the United States has experienced a recent increase in cases of acute flaccid myelitis, a rare disease of children [9]. Diagnosis is based on a metagenomic analysis (i.e., culture-independent sequence searches conducted on an assemblage of microbial gene sequences in a biologic sample) of DNA obtained from nasopharyngeal swabs.…”