Intervertebral disc disease and aortic thromboembolism are the most common causes of acute paralysis in dogs and cats presenting to an emergency clinic.

BACKGROUND: Acute paralysis is a common presentation in small animal emergency clinics, but the aetiological prevalence has not been reported. Knowledge of diagnosis frequency aids prioritisation of differential diagnoses, facilitates resource planning and clinical trial design. METHODS: Medical records from NC State Veterinary Hospital Emergency Room were searched over a five-year period to identify cases presenting with acute non-ambulatory paraparesis or paralysis. Signalment and diagnosis category were extracted. RESULTS: Acute paralysis was the presenting problem in 845 of 21,535 (3.9 per cent) dogs and 66 of 4589 (1.4 per cent) cats admitted over this period. Intervertebral disc disease (IVDD) was the most common cause (608 of 845; 72 per cent) in dogs, followed by vascular disease (34 of 845; 4.0 per cent). Other diagnostic categories accounted for the remaining 20 per cent. Dachshunds were the most common breed (263 of 845; 31.1 per cent), then Labrador retrievers (57 of 845; 6.7 per cent). In cats, aortic thromboembolism (ATE) was the most common diagnosis, occurring in 40 of 66 (60.6 per cent), followed by IVDD (7 of 66; 10.6 per cent). Other diagnostic categories accounted for 30.3 per cent. Six of 845 (0.7 per cent) dogs and two of 66 (3 per cent) cats were categorised as pseudoparalysis with a non-neurological diagnosis. CONCLUSIONS: IVDD and ATE are the overwhelming causes of acute paralysis in dogs and cats, respectively, with approximately 28 per cent of dogs and 40 per cent of cats having a different diagnosis.

Plasma Neurofilament Light Chain as a Translational Biomarker of Aging and Neurodegeneration in Dogs.

Age is a primary risk factor for multiple comorbidities including neurodegenerative diseases. Pet dogs and humans represent two populations that have experienced a significant increase in average life expectancy over the last century. A higher prevalence of age-related neurodegenerative diseases has been observed across both species, and human diseases, such as Alzheimer's disease (AD) and amyotrophic lateral sclerosis (ALS), have canine analogs, canine cognitive dysfunction (CCD), and degenerative myelopathy (DM) respectively. In humans, protein biomarkers have proved useful in the prediction and diagnosis of neurodegeneration. Molecular signatures of many proteins are highly conserved across species. In this study, we explored the potential of the neuronal cytoskeletal protein neurofilament light chain (NfL) as a biomarker of neuro-aging in dogs using an ultrasensitive single-molecule array assay to measure plasma concentrations. Healthy dogs of different ages and dogs affected with CCD and DM were evaluated. The mean plasma NfL concentrations in the different age groups of the healthy population were as follows: 4.55 ± 1.70 pg/mL in puppy/junior group (0.43-2 years), 13.51 ± 6.8 pg/mL in adult/mature group (2.1-9 years), and 47.1 ± 12.68 pg/mL in geriatric/senior group (9.3-14.5 years). Concentrations in dogs with DM (7.5-12.6 years) and CCD (11.0-15.6 years) were 84.17 ± 53.57 pg/mL and 100.73 ± 83.72 pg/mL, respectively. Plasma NfL increases in an age-dependent manner and is significantly elevated in dogs diagnosed with neurodegenerative disease. This work identified plasma NfL as a key clinical index of neuro-aging and neurodegeneration in pet dogs. Our findings mirror recent reports from human neurodegenerative diseases.