Meningitis caused by Capnocytophaga canimorsus: When to expect the unexpected

In this article we review the available data concerning meningitis caused by Capnocytophaga canimorsus. The clinical presentation of this rare condition is described with the emphasis on associated conditions and management issues. Two additional cases, illustrating the difficulties in recognizing this rare disease, are presented. Reviewing a total of 28 reported cases, a preceding bite-incident by a cat or dog, or close contact with these animals, was described in the majority of cases (89%). Patients had a median age of 58 years; splenectomy and alcohol abuse were noted in, respectively, 18% and 25% of patients. Only in one case immune suppressive drug use was reported. The diagnosis C. canimorsus meningitis should be considered in healthy and immunocompromised adults, especially after splenectomy, who present with symptoms attributable to meningitis and a history of recent exposure to dogs or cats. The possibility of this condition has implications for both the diagnostic work-up and the treatment of the patient.