Metronidazole-induced encephalopathy in a patient with Crohn's disease

Area of Science:

• Neurology
• Pharmacology
• Gastroenterology

Background:

• Metronidazole is a common antibiotic for anaerobic infections.
• Metronidazole-induced encephalopathy (MIEP) is a rare, reversible neurological condition.
• The exact mechanism and route-specific neurotoxicity of MIEP are not fully understood.

Purpose of the Study:

• To report a case of MIEP in a Crohn's disease patient.
• To explore potential differences in neurotoxic effects between oral and intravenous metronidazole administration.
• To investigate MIEP following long-term oral metronidazole exposure and subsequent IV administration.

Main Methods:

• Case report of a 64-year-old male Crohn's disease patient.
• Detailed clinical observation of neurological symptoms post-IV metronidazole.
• Brain MRI (fluid-attenuated inversion recovery) to identify neurotoxic changes.
• Monitoring of neurological status and MRI findings after metronidazole discontinuation.

Main Results:

• The patient developed acute encephalopathy, aphasia, and weakness after a single IV metronidazole dose.
• Brain MRI revealed high-intensity signals in the medial thalamus, midbrain, and pontine tegmentum.
• Neurological symptoms and MRI abnormalities resolved after stopping metronidazole.
• Mild cognitive dysfunction persisted two months post-encephalopathy.

Conclusions:

• This case suggests potential differential neurotoxicity between oral and IV metronidazole routes.
• MIEP can occur even after prolonged oral exposure and subsequent IV administration.
• Prompt discontinuation of metronidazole is crucial for reversing MIEP symptoms.