Metronidazole-induced encephalopathy caused by hyperbaric oxygen therapy in a patient with mandibular osteomyelitis

Area of Science:

• Neurology
• Pharmacology
• Hyperbaric Medicine

Background:

• Metronidazole (MNZ) is a common antibiotic for anaerobic bacterial and protozoal infections.
• Metronidazole-induced encephalopathy (MIE) is a recognized but poorly understood adverse effect.
• The association between MIE and hyperbaric oxygen therapy (HBO) has not been previously documented.

Observation:

• A 68-year-old male with mandibular osteomyelitis received 49 days of metronidazole and five HBO sessions.
• The patient developed peripheral neuropathy, speech disturbance, nausea, and gait disturbance after 47 days of metronidazole.
• Brain MRI showed hyperintense lesions in the cerebellar dentate nuclei, indicative of MIE.

Findings:

• The patient's neurological symptoms, including ataxia, significantly improved within 15 days of discontinuing metronidazole.
• This case presents the first reported instance potentially linking MIE with concurrent hyperbaric oxygen therapy.

Implications:

• This case suggests a possible interaction or potentiating effect between metronidazole and HBO therapy leading to MIE.
• Further research is warranted to investigate the safety and potential risks of combined metronidazole and HBO treatment.
• Clinicians should consider MIE in patients presenting with neurological symptoms while undergoing treatment with metronidazole, especially if also receiving HBO therapy.