Knowing where to look: 'Meningococcal' septicaemia following a dog bite

The patient presentation of septic shock and purpuric rash is commonly attributed to meningococcal septicaemia. We describe a case of similar presentation where initial cultures and antigen testing were negative for meningococcus and the isolation of an unusual organism, Capnocytophaga canimorsus, was only made after obtaining a history of a dog bite and liaison with the microbiology laboratory. The epidemiology and clinical features of Capnocytophaga canimorsus infection is discussed, together with the antibiotic management of dog bites.