Post-infectious cerebellitis is described as an immune-mediated cerebellar inflammatory syndrome that develops after a preceding infection or, rarely, vaccination, following a latent interval. The clinical spectrum includes benign post-infectious/acute cerebellar ataxia (ACA), more severe acute cerebellitis (AC) with leptomeningeal enhancement and potential mass effect, and rare life-threatening acute fulminant cerebellitis (AFC) carrying a risk of hydrocephalus. The evidence informing this syndrome is largely composed of individual case reports and small case series.
The review used PRISMA-guided methodology. Electronic database searches, citation tracking, and supplementary bibliography searches identified 899 records for screening. After removing duplicates and applying eligibility criteria, 47 studies (including case reports, case series, and cohort studies) were included in the qualitative synthesis. Patient-level data were extractable and pooled for quantitative analysis in 73 individuals. The authors report that evidence is heterogeneous and primarily lower-level observational data.
The pooled cohort (n = 73) had a mean age of 24.5 years, with an age range from 7 months to 74 years. The cohort included 40 pediatric and 28 adult patients; age status was not explicitly recorded for five patients in the abstract. Sex was reported for 70 patients, of whom 51 (72.9%) were male. These pooled demographics reflect the cases available in the included reports but do not represent population-level incidence.
Cases were classified using neuroimaging findings and the presence of life-threatening features into three subtypes:
Neuroimaging distinctions reported in the review include leptomeningeal enhancement and features suggesting mass effect in AC and hydrocephalus risk in AFC. Classification correlated with clinical severity and guided management discussions in the source literature.
The most frequently identified trigger across pooled cases was SARS-CoV-2 (24/73, 32.9%). Other categories reported were no pathogen identified (18/73, 24.7%), varicella-zoster virus (8/73, 11.0%), Epstein-Barr virus (5/73, 6.8%), and influenza (5/73, 6.8%). The review emphasizes heterogeneity in identified etiologies and that a substantial proportion of cases had no pathogen detected.
Reported therapies in the pooled cohort focused on immunomodulation and antiviral treatment where relevant. The most commonly used therapy was corticosteroids (54/73, 74.0%). Antivirals were administered in 35/73 patients (47.9%), IVIG was used in 19/73 (26.0%), and plasma exchange was reserved for refractory cases. The review notes that corticosteroid-based regimens were a frequent component of management across etiologies and severity subgroups, but specific dosing regimens, duration, and comparative effectiveness were not synthesized in the abstract-level summary.
Outcomes in the pooled cohort were as follows:
Recovery by clinical subtype reported in the pooled data included complete recovery in 58.8% of ACA cases, 69.2% of AC cases, and 69.2% of AFC cases. The single recorded death occurred in an adult with COVID-19-associated necrotizing encephalopathy and was reported within the AFC subgroup.
The review highlights that the underlying evidence base is heterogeneous and dominated by case reports and small series, limiting the strength of causal or comparative inferences. Patient-level pooling provides descriptive insight but cannot substitute for controlled studies. The authors conclude that post-infectious cerebellitis is a clinically heterogeneous, largely immune-mediated syndrome with a generally favorable prognosis in this pooled series, particularly with corticosteroid-based immunotherapy, while acknowledging variation in outcomes by etiology and severity subgroup. Details such as standardized treatment protocols, long-term follow-up, and higher-quality comparative evidence were not reported in the abstract and would require consultation of the full text and cited references for more granular data.