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A rare etiology of mild encephalitis/encephalopathy with reversible splenial lesion
Hiroki Shimono1, Yoji Hoshina2, Ei Ogawa3
1Center for Clinical Education and Training Takamatsu Red Cross Hospital Takamatsu Japan.
Abstract:
Legionella is a rare cause of mild encephalitis/encephalopathy with reversible splenial lesion, which should be considered in patients with risk factors. Brain magnetic resonance imaging (MRI) and legionella urinary antigen test can help the diagnosis since cerebrospinal fluid (CSF) can be normal.
Insights
Legionella bacteria can cause a rare, mild brain inflammation (encephalitis) with temporary MRI changes. Consider Legionella in at-risk patients, as standard spinal fluid tests may be normal.
Area of Science:
- Neurology
- Infectious Diseases
Background:
- Encephalitis/encephalopathy is inflammation of the brain.
- Legionella is an uncommon cause of central nervous system infections.
Purpose of the Study:
- To highlight Legionella as a potential cause of mild encephalitis/encephalopathy.
- To emphasize the diagnostic utility of specific tests in suspected cases.
Main Methods:
- Case review and literature analysis.
- Brain magnetic resonance imaging (MRI) interpretation.
- Legionella urinary antigen testing.
Main Results:
- Legionella can present as mild encephalitis/encephalopathy.
- A characteristic finding is a reversible splenial lesion on MRI.
- Cerebrospinal fluid (CSF) analysis may not show abnormalities.
- Urinary antigen tests can aid in diagnosis.
Conclusions:
- Legionella should be considered in the differential diagnosis of encephalitis/encephalopathy, particularly in patients with relevant risk factors.
- Brain MRI and legionella urinary antigen testing are valuable diagnostic tools when CSF is normal.
