Acute Flaccid Myelitis in Children in Zhejiang Province, China

Abstract

In July-December 2018, an outbreak of polio-like acute flaccid myelitis (AFM) occurred in Zhejiang province, China. Enterovirus (EV)-D68 infection has been reported to be associated with AFM. This study aimed to investigate the clinical presentation, laboratory findings, and outcomes of AFM patients. We investigated the clinical and virologic information regarding the AFM patients, and real-time PCR, sequencing, and phylogenetic analysis were used to investigate the cause of AFM. Eighteen cases met the definition of AFM, with a median age of 4.05 years (range, 0.9-9 years), and nine (50%) were EV-D68 positive. Symptoms included acute flaccid limb weakness and cranial nerve dysfunction. On magnetic resonance imaging, 11 (61.1%) patients had spinal gray matter abnormalities. Electromyography results of 16 out of 17 patients (94.1%) were abnormal. Cerebrospinal fluid (CSF) pleocytosis was common (94.4%), while CSF protein concentration was normal in all patients. There was little improvement after early aggressive therapy. Phylogenetic analysis revealed that EV-D68 subclade B3 was the predominant lineage circulating in Zhejiang province in 2018.

Acute flaccid myelitis a review of the literature

“…In reports or manuscripts published on patients in Argentina, China, and Japan authors did not find a significant difference in their patient population compared to the United States population ( 19 – 22 ). Most patients had febrile episodes and respiratory infections like those in the United States ( 19 – 22 ). This is important to note because it further supports a possible viral infection, like EV-D68, as a component in the pathobiology of AFM.…”

“…Stool studies for viral identification were commonly conducted, but negative most of the time ( 3 , 5 , 9 , 13 ). In the United States, < 10% of stool studies were positive compared to Europe, Argentina, and China which had a positive rate of 35% ( 5 , 19 – 22 ). Most international evaluations were based on 2016–2018 data compared to the 2014–2016 United States data.…”

“…Most patients did not get an electromyography (EMG) or nerve conduction studies (NCS) since characteristic findings do not emerge until later in the course. The patients that did get NCS showed a reduction in the compound mean action potentials and reduced amplitude with preserved sensory nerve action potentials ( 22 , 29 , 39 – 41 ). EMG showed a reduced recruitment of motor unit action potentials consistent with anterior horn damage ( 22 , 29 , 39 – 41 ).…”

Acute Flaccid Myelitis: Review of Clinical Features, Diagnosis, and Management with Nerve Transfers

“…4–7 Many patients also report cranial nerve involvement and neck/trunk weakness. 1,5,7,13,14,20,23,25,33,49,52,54,58,61,77,87 The most severe manifestation of weakness in AFM is respiratory failure from phrenic nerve involvement necessitating mechanical ventilation.…”

Serological Study of Neutralizing Antibodies Against Enterovirus D68 Among Healthy Population in Xiamen, China

“…EV-D68 infection was rst identi ed in Beijing, China, in 2006 [14]. Since then, more and more EV-D68-related illnesses had been reported in other regions of China, such as Shandong [15], Zhejiang [16], Shanghai [17], Jiangsu [18], Hong Kong [19] and Taiwan [20]. However, no vaccine or speci c therapy is yet available.…”