The best questions often stem from the inquisitive learner. As educators, we love—and are always humbled—by those moments when we get to say “I don’t know.” For some of these questions, you may already know the answers. For others, you may never have thought to ask the question. For all, questions, comments, concerns, and critiques are encouraged. Welcome to the Kids Korner.

In Children Presenting to the ED, What Is the Most Common Cause of Ataxia?

Ataxia in children can be fear-inducing for parents. Sometimes the child develops an acutely abnormal gait; sometimes the child manifests ataxia simply as the refusal to ambulate. Either way, ataxia in children can often be difficult to assess because children have a wide range of gaits considered normal. When a child does develop ataxia, what are the most likely causes? A recent 11-year retrospective study performed at a tertiary-care outpatient Pediatric Neurology clinic identified 120 children with acute ataxia.¹ Acute ataxia was defined as ataxia less than or equal to 4 weeks and the authors excluded children with underlying neurological diagnoses that could explain the ataxia. The study identified 120 children with ataxia and 82 percent were 1 to 6 years in age and 16 percent were older than 6 years of age. Acute post-infectious cerebellar ataxia was the most common diagnosis (59.2 percent; 71/120 patients), followed by drug intoxication (8.3 percent; 10/120 patients), and opsoclonus myoclonus ataxia (8.3 percent; 10/120 patients). Other less common causes included cerebellar stroke (1.7 percent) and acute disseminated encephalomyelitis (1.7 percent). Another retrospective outpatient Pediatric Neurology clinic study demonstrated similar etiologic results with acute post-infectious cerebellar ataxia identified again as the most common cause (51.2 percent) of acute ataxia.² It’s important to note, though, that the practice settings in these studies were outpatient neurology clinics, so the causes of presentation may not reflect our ED setting.

Specific to the ED setting, there’s some data on this topic but not a ton. A multi-center retrospective study of 11 Italian pediatric emergency departments identified 509 children with acute ataxia over an 8-year period.³ The median age was 4.4 years. Like the above studies, the most common identified cause of acute ataxia in this study was also acute post-infectious cerebellar ataxia (33.6 percent; 171 cases), followed by CNS tumors (11.2 percent; 57 cases), and migraine disorders (8.3 percent; 42 cases). Only 35 cases (6.9 percent) were secondary to drug overdose or substance abuse. Another 2019 retrospective study demonstrated a similar incidence of acute post-infectious cerebellar ataxia (36.2 percent), but ingestion accounted for a larger percentage of the cases (15.6 percent).⁴

A separate pediatric ED study retrospectively identified 88 patients aged 1 to 18 years with ataxia over a three year period.⁵ The authors included children with ataxic symptoms less than 30 days and divided the patients into two groups: clinically urgent neurological pathology (CUNP; n=37) and patients who were not clinically urgent (No CUNP; n=51). Children with previously-known diseases associated with ataxia were excluded. Clinically urgent neurological pathology (CUNP) was defined as any nervous system disorder requiring early diagnosis and prompt medical or surgical treatment such as neoplastic, cerebrovascular, and infectious central nervous system disorders, demyelinating disease, acute neuropathies, and CNS malformations. The median age was 5 years and the majority of patients (58 percent) were categorized in the “No CUNP” group which included post-infectious/parainfectious cerebellitis (i.e., post-infectious cerebellar ataxia). The most common overall cause of ataxia, again, was post-infectious/parainfectious cerebellitis (45.5 percent), followed by acute cerebellitis (10.2 percent), and Guillain-Barre (9 percent). While other urgent causes of ataxia within the CUNP group included things like encephalomyelitis, stroke, tumors, and AV malformations, these were uncommon and the authors make little mention of the duration of ataxia and the association with clinically urgent pathology—compared to non-urgent pathology.

Summary

The most common cause of acute ataxia in children is post-infectious cerebellar ataxia and accounts for approximately half of the cases of acute ataxia.

Dr. Jones is associate professor at the department of emergency medicine & pediatrics and the program director of pediatric emergency medicine fellowship at the University of Kentucky in Lexington, Kentucky.

Dr. Cantor is the emeritus medical director for the Central New York Poison Control Center and professor of emergency medicine and pediatrics in Syracuse, New York.

References

1. Thakkar K, Maricich SM, Alper G. Acute ataxia in childhood: 11-year experience at a major pediatric neurology referral center. J Child Neurol. 2016;31(9):1156-1160.
2. Kirik S, Aslan M, Ozgor B, et al. Acute ataxia in childhood: clinical presentation, etiology, and prognosis of single-center experience. Pediatr Emerg Care. 2021;37(3):e97-e99.
3. Garone G, Reale A, Vanacore N, et al. Acute ataxia in paediatric emergency departments: a multicentre Italian study. Arch Dis Child. 2019;104(8):768-774.
4. Luetje M, Kannikeswaran N, Arora R, et al. Utility of neuroimaging in children presenting to a pediatric emergency department with ataxia. Pediatr Emerg Care. 2019;35(5):335-340.
5. Yaradilmiş RM, Güngör A, Bodur I, et al. Evaluation of acute ataxia in the pediatric emergency department: etiologies and red flags. Pediatr Neurol. 2023;139:1-6.