Primary bacterial ventriculitis in adults, an emergent diagnosis challenge: report of a meningoccal case and review of the literature.

Background: Defined by an infection of the ventricular system of the brain, ventriculitis is usually known as a health-care associated infection. In contrast, primary pyogenic ventriculitis complicating community-acquired meningitis is uncommon, and mainly described in infants. Only seven cases that have occured in adults have been found in the international literature.

Case Presentation: We report here a new case due to Neisseria meningitidis occurring in an 85 year-old-man. The comparison with previous reports allows to drawn several conclusions: (i) cases occurred in relatively old adults (median age: 65 years); (ii) Streptococcus pneumoniae, N. meningitiditis and Staphylococcus aureus are the leading responsible pathogens; (iii) atypical clinical presentation seems the rule in which meningism often lacks; (iv) in absence of clinical or biological specific parameters, modern brain imaging such as magnetic resonance imaging with gadolinium enhancement is of utmost importance for the diagnosis, leading to anticipate an increase of the diagnosis in the near future, thanks to easier access to such exploration; (v) death or serious sequelae commonly occurred; (vi) prolonged antibiotic courses (6 weeks to 3 months) have been used, without strong rational. In the given case, the patient presented with a lack of meningeal irritation signs. The diagnosis was made by MRI considering a lasting confused state. A four-week antibiotic regimen was successful, combining two weeks of intravenous cefotaxime followed by two weeks of oral levofloxacin much easier to administrate and allowing early rehabilitation.

Conclusion: Primary bacterial ventriculitis is a real diagnosis challenge. Larger indications of MRI for bacterial meningitis, particularly in cases with an atypical presentation or poor evolution would certainly increase the number of diagnosis.