Results of routine thoracic radiographic examinations rarely impact the plan to proceed with anesthetic procedures in dogs with presumed acute intervertebral disc herniation.

Introduction: Acute thoracolumbar intervertebral disc herniation (IVDH) constitutes an emergency because associated neurological clinical signs can be progressive, with prognosis dependent on preoperative presence of deep pain perception. Pre-anesthetic thoracic radiographs are routinely performed to evaluate for potential pathology that could result in increased risk or change in overall prognosis. However, due to the emergent nature of this disease, the weight of thoracic radiographic findings on treatment plans for these dogs in unknown. The objective of this study was to investigate the clinical benefit of thoracic radiographs prior to advanced spinal imaging and surgery for acute non-ambulatory dogs with suspected T3-L3 myelopathy. Methods: Consecutive dogs presented with presumed acute IVDH between July 2020-July 2022 were identified, and medical records were reviewed retrospectively. Age, body weight, and alteration of treatment plan were compared between the dogs with positive thoracic pathology identified on thoracic radiographs and those with negative thoracic pathology. Results: Only 2/105 dogs had their diagnostic and treatment plans changed due to thoracic radiographic findings. Dogs with radiographic pathology diagnosed (2/16) were more likely to have their treatment plans changed than dogs with no radiographic pathology (0/89) (p = 0.014). The odds of radiographic thoracic pathology were 4.6 times higher in dogs aged 12 years or older [OR 4.6 (95%CI 1.2-17, p = 0.026]. Discussion: Performing routine thoracic radiography prior to advanced (anesthetized) diagnostic spinal imaging in presumed IVDH cases rarely resulted in a change to the treatment plan, thought eh practice may be clinically relevant in dogs 12 years of age or older.

The NLRP3 inflammasome and bruton's tyrosine kinase in platelets co-regulate platelet activation, aggregation, and in vitro thrombus formation.

Cleavage of interleukin-1ß (IL-1ß) is a key inflammatory event in immune cells and platelets, which is mediated by nucleotide-binding domain leucine rich repeat containing protein (NLRP3)-dependent activation of caspase-1. In immune cells, NLRP3 and caspase-1 form inflammasome complexes with the adaptor proteins apoptosis-associated speck-like protein containing a CARD (ASC) and bruton's tyrosine kinase (BTK). In platelets, however, the regulatory triggers and the functional effects of the NLRP3 inflammasome are unknown. Here, we show in vitro that the platelet NLRP3 inflammasome contributes to platelet activation, aggregation, and thrombus formation. NLRP3 activity, as monitored by caspase-1 activation and cleavage and secretion of IL-1ß, was upregulated in activated platelets, which was dependent on platelet BTK. Pharmacological inhibition or genetic ablation of BTK in platelets led to decreased platelet activation, aggregation, and in vitro thrombus formation. We identify a functionally relevant link between BTK and NLRP3 in platelets, with potential implications in disease states associated with abnormal coagulation and inflammation.