Recurrent encephalitis due to trimethoprim intake

J Hedlund1, E Aurelius, J Andersson

  • 1Department of Infectious Diseases, Danderyd Hospital, Stockholm, Sweden.

Insights

This study reports a rare case of meningitis and encephalitic symptoms in a 76-year-old woman linked to trimethoprim. The patient experienced two episodes, highlighting a potential adverse drug reaction not previously documented.

Area of Science:

  • Neurology
  • Pharmacology
  • Infectious Diseases

Background:

  • Trimethoprim is an antibiotic commonly used to treat bacterial infections.
  • Adverse neurological events associated with trimethoprim are rare but can be serious.
  • Meningitis and encephalitic symptoms represent significant neurological complications.

Purpose of the Study:

  • To report a unique case of meningitis and encephalitic symptoms.
  • To investigate the potential link between trimethoprim and neurological dysfunction.
  • To highlight an uncharacteristic adverse drug reaction to trimethoprim.

Main Methods:

  • Case report of a 76-year-old female patient.
  • Clinical observation of two distinct episodes of illness.
  • Neurological examination and electroencephalogram (EEG) analysis.
  • Review of medication history, focusing on trimethoprim intake.

Main Results:

  • The patient experienced two episodes of meningitis.
  • Encephalitic symptoms, including cerebral function disturbances, were observed.
  • Pathological findings on electroencephalogram correlated with neurological symptoms.
  • Both episodes were temporally associated with trimethoprim use.

Conclusions:

  • Trimethoprim may be associated with severe neurological adverse events, including meningitis and encephalitis.
  • This case represents a previously unreported presentation of trimethoprim-induced neurological toxicity.
  • Clinicians should consider trimethoprim as a potential cause in patients presenting with unexplained meningitis and encephalitic symptoms.

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