The Alien Limb Phenomenon in Creutzfeldt-Jakob Disease: A Systematic Review of Case Reports

Alien limb phenomenon (ALP) is a clinical finding seen in numerous neurological disorders, including Creutzfeldt-Jakob disease (CJD). We aimed to conduct a systematic review to update advances in understanding the classification and pathophysiology of ALP in CJD. We used PubMed advanced-strategy searches and only included full-text observational studies and case reports conducted on humans and written in English. We used the PRISMA protocol for this systematic review and the Methodological Quality of Case Reports tool to assess the bias encountered in each study. After applying the inclusion/exclusion criteria, 10 case reports were reviewed. Two independent reviewers analyzed data and confirmed the phenotype of each case of the alien limb in CJD separately. Overall, the most prevalent ALP phenotype presenting in patients with CJD was the posterior phenotype, usually in the early stages of the disease. Our findings corroborate previous research in demonstrating the pathophysiology behind ALP in CJD. We suggest physicians suspect CJD whenever patients present with ALP as the initial symptom.