Methods: A systematic review of the peer-reviewed English literature (PubMed, Embase, Ovid Medline) from January 1966 - March 2018 was performed to identify cases of C. canimorsus meningitis in addition to our case. Data collected included demographics, risk factors, cerebrospinal fluid (CSF) findings, PCR testing, treatment, and outcomes. Descriptive statistics are presented as numbers (percentages) and medians (ranges).
Results: A total of 37 cases with a median age of 63.5 years (range 12 days-83 years) with a male predominance (75%). A relatively low proportion had an immunocompromised state: 17% splenectomy and 6% steroid use. The most common risk factor was alcoholism (19%). Sixty four percent reported a dog bite (all <10 days prior to presentation); 22% non-bite dog exposure; 3% cat bite; and 11% no animal contact. CSF mean white cells of 1894 cells/mm3, neutrophils 76% (+/-19%), protein of 225 mg/dl (+/-149), and glucose CSF/serum ratio of 0.24 (+/-0.15). In 16 (43%) cases blood cultures were positive for C. canimorsus (median of 4.3 days) and 27 (73%) had positive CSF cultures (median 4.4 days). PCR established the diagnosis in 7 (19%) cases. Antibiotic therapy was given for a median of 14 days (range 7-42 days). Prognosis was overall favorable with one (3%) mortality; 19% of survivors had sequelae: 4 hearing loss, 1 headaches, 2 neurological deficits, and 2 with extremity amputations.
Conclusion: C. canimorsus meningitis is a rare clinical entity occurring in patients of all ages typically after dog exposure. While classically considered a disease of immunocompromised patients, most cases occurred in previously healthy, immunocompetent persons. Diagnosis may be established by PCR and testing should be considered in culture-negative cases with associated risk factors. Outcome was generally favorable after a median antibiotic duration of 14 days.
N. Crum-Cianflone, None