EXPRESS: Oesophageal necrosis post impaction as a proposed cause of markedly elevated serum Creatine Kinase activity in a juvenile cat

Case Summary: A 21-week-old male neutered domestic medium-hair cat presented with a history of acute, severe regurgitation. Physical examination was unremarkable with no musculoskeletal or neurological abnormalities. Initial serum biochemistry identified marked elevation in creatine kinase (CK) (905,409 U/L; reference interval [RI] 50-400), which persisted after 24 hours of supportive care (32,491 U/L; RI 50-400). Serology for Toxoplasma gondii was negative. Radiography and ultrasound found severe caudal oesophageal impaction. The kitten was euthanased and autopsy confirmed oesophageal food impaction, and severe, focally extensive oesophageal necrosis. The underlying cause of the oesophageal impaction was not definitively determined. Other than the oesophageal necrosis, there were no other autopsy findings to explain the elevated CK. Relevance and novel information: Oesophageal necrosis may be associated with severe elevations in CK concentrations and oesophageal disease should be considered if there is no obvious trauma, polymyopathy or cardiac disease in feline patients with markedly elevated CK.