Paroxysmal dyskinesia in 31 dogs (2020-2025)

ABSTRACT: This retrospective study aimed to identify dogs with a presumptive diagnosis of paroxysmal dyskinesia (PD) and describe its phenotypical characterization, treatment, and outcome. A total of 31 dogs (45,2% females and 54,8% males) examined at two veterinary neurology services from January 2020 to April 2025 were included. The mean age at clinical onset was 52.2 months (range, 2-137 months). Nine dogs were mixed-breed (29%), eight were German Spitz (25.8%), four were Dachshunds (12.9%), two were Chihuahuas (6.4%), two were Shih Tzus (6.4%), and one each were Siberian Husky, Labrador Retriever, Pinscher, and Maltese (3.2% each). A presumptive diagnosis was established based on independent analysis of the video recordings of the episodes. Limb dystonia was present in all dogs, whereas associated dystonic head tremors were present in 61.3% of the cases. Other clinical signs included generalized tremors (38.7%), kyphosis (32.2%), and incoordination (12.9%). The mean episode duration was 6.8 minutes (range, 1-60 minutes). Triggers such as stress and/or excitement were identified in 15 dogs (48.4%). Seventeen dogs (54.8%) were treated for the episodes: 11 with antiseizure drugs (54.5% improvement) and 6 with a gluten-free diet (66.7% improvement). Fourteen dogs (45.2%) did not receive any treatment, and spontaneous remission was seen in six (42.8%). Paroxysmal dyskinesia can affect dogs of various breeds and ages with no sex predilection. The disorder manifests as a range of clinical signs, including limb dystonia, which was present in all dogs in this study. Stress and excitement were identified as the main triggers in nearly half of the cases. Both the treated and untreated dogs showed clinical improvement, highlighting the heterogeneity of PD. Further studies are needed to better understand the disease and its progression.