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Published on: November 5, 2019
[Meningitis due to Capnocytophaga canimorsus without dog bite]
Alain Drouet1, Salim Smati, Marie-Hélène Ferrer
1Service de Neurologie, HIA Desgenettes, Lyon. drouetalain@yahoo.fr
Introduction:
Capnocytophaga canimorsus is a fusiform and filamentous gram-negative rod, part of the normal oral flora of dogs and cause rare human febrile acute meningitis, usually severe but curable.
Observation:
A sixty years old man presented a severe acute meningitis with fever and confusion. CSF show 4,000 cells/mm3 with 83% neutrophilis, increased protein level (5,02 g/L), very low glucose and positive Gram stain result. The patient fully and quickly recovered with antibiotherapy for 22 days. Bacteriological diagnosis was made by genomic study from CSF culture. The patient has a close contact with his dog without being recently bitten.
Discussion:
Diagnosis, suggested by bites or contact with dog or cat, gram-negative bacilli with gram stain of CSF specimen, is possible by prolonged culture of CSF or blood sample, with if necessary genomic study. Antibioprophylaxis is strongly recommended in cases of deep bite wounds and for immunocompromised patients.
Insights
Capnocytophaga canimorsus, a bacteria from dog saliva, can cause severe meningitis in humans. Prompt diagnosis and antibiotic treatment lead to full recovery, highlighting the importance of considering animal contact in meningitis cases.
Area of Science:
- Infectious Diseases
- Microbiology
- Neurology
Background:
- Capnocytophaga canimorsus is a gram-negative rod found in canine oral flora.
- It can cause rare, severe, but treatable human febrile acute meningitis.
Observation:
- A 60-year-old man presented with severe meningitis symptoms including fever and confusion.
- Cerebrospinal fluid analysis revealed high cell count, elevated protein, low glucose, and positive Gram stain.
- The patient had close contact with a dog and recovered fully with a 22-day antibiotic course.
Findings:
- Genomic study of CSF culture confirmed Capnocytophaga canimorsus infection.
- Early Gram stain of CSF is crucial for identifying gram-negative bacilli.
Implications:
- Prompt diagnosis of Capnocytophaga canimorsus meningitis is possible with CSF Gram stain and genomic analysis.
- Antibiotic prophylaxis is recommended for deep bite wounds and immunocompromised individuals due to potential dog or cat contact.
- Early and appropriate antibiotherapy ensures a full recovery from this severe infection.
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