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Meningitis, meningoencephalitis and encephalitis in Bern: an observational study of 258 patients
Anamaria Ungureanu1, Julia van der Meer1, Antonela Bicvic1
1Department of Neurology, University Hopsital and University of Bern, Inselspital, Bern, Switzerland.
Background:
Depending on geographic location, causes of encephalitis, meningoencephalitis and meningitis vary substantially. We aimed to identify the most frequent causes, clinical presentation and long-term outcome of encephalitis, meningoencephalitis and meningitis cases treated in the Inselspital University Hospital Bern, Switzerland.
Methods:
In this monocentric, observational study, we performed a retrospective review of clinical patient records for all patients treated within a 3-year period. Patients were contacted for a telephone follow-up interview and to fill out questionnaires, especially related to disturbances of sleep and wakefulness.
Results:
We included 258 patients with the following conditions: encephalitis (18%), nonbacterial meningoencephalitis (42%), nonbacterial meningitis (27%) and bacterial meningoencephalitis/meningitis (13%). Herpes simplex virus (HSV) was the most common cause of encephalitis (18%); tick-borne encephalitis virus (TBEV) was the most common cause of nonbacterial meningoencephalitis (46%), enterovirus was the most common cause of nonbacterial meningitis (21%) and Streptococcus pneumoniae was the most common cause of bacterial meningoencephalitis/meningitis (49%). Overall, 35% patients remained without a known cause. After a median time of 16 months, 162 patients participated in the follow-up interview; 56% reported suffering from neurological long-term sequelae such as fatigue and/or excessive daytime sleepiness (34%), cognitive impairment and memory deficits (22%), headache (14%) and epileptic seizures (11%).
Conclusions:
In the Bern region, Switzerland, TBEV was the overall most frequently detected infectious cause, with a clinical manifestation of meningoencephalitis in the majority of cases. Long-term neurological sequelae, most importantly cognitive impairment, fatigue and headache, were frequently self-reported not only in encephalitis and meningoencephalitis survivors but also in viral meningitis survivors up to 40 months after acute infection.
Insights
In Switzerland, tick-borne encephalitis virus (TBEV) is a leading cause of meningoencephalitis. Many patients experience long-term neurological issues like fatigue and cognitive problems following infections.
Area of Science:
- Neurology
- Infectious Diseases
- Epidemiology
Background:
- Prevalence of encephalitis, meningoencephalitis, and meningitis varies geographically.
- Understanding regional causes and outcomes is crucial for effective treatment.
Purpose of the Study:
- To identify frequent causes of encephalitis, meningoencephalitis, and meningitis in Bern, Switzerland.
- To analyze clinical presentations and long-term outcomes in affected patients.
Main Methods:
- Retrospective review of clinical records for 258 patients over 3 years.
- Follow-up telephone interviews and questionnaires assessing long-term sequelae, particularly sleep disturbances.
Main Results:
- Tick-borne encephalitis virus (TBEV) was the most common infectious cause (meningoencephalitis).
- Herpes simplex virus (HSV) caused most encephalitis; enterovirus and Streptococcus pneumoniae caused meningitis/meningoencephalitis.
- 35% of cases remained without a known cause.
- 56% of 162 follow-up patients reported long-term neurological sequelae (fatigue, cognitive impairment, headache, seizures).
Conclusions:
- TBEV is the primary infectious cause of meningoencephalitis in the Bern region.
- Significant rates of long-term neurological sequelae, including cognitive impairment and fatigue, are reported even after viral meningitis.
