[A dog owner in his 70s with severe abdominal pain]

Capnocytophaga canimorsus is a gram-negative bacterium found in the oral cavity of dogs and cats. It can cause severe infections, including sepsis, especially in immunocompromised individuals, though rare cases also occur in immunocompetent patients.

A man in his seventies with hypertension developed fever, chills and abdominal pain after being scratched by his dog. He presented with severe abdominal pain, tachycardia, fever and elevated lactate levels. Initial CT scans did not reveal abdominal pathology, but septic shock was suspected. Despite treatment with broad-spectrum antibiotics, the patient deteriorated and developed disseminated intravascular coagulation (DIC) and multiorgan failure. He died 18 hours after admission. Blood cultures were subsequently positive for C. canimorsus.

This case highlights the possibility of rapid progression of sepsis caused by C. canimorsus, even in immunocompetent individuals. The autopsy confirmed septic shock, DIC and Waterhouse-Friderichsen syndrome, consistent with a fulminant infection. The case emphasises the importance of considering C. canimorsus in septic patients with dog-related injuries, including where this is no clear history of dog bites, and underscores the need for early empirical antibiotic treatment to improve survival.