Ertapenem-induced encephalopathy

Area of Science:

• Neuroscience
• Pharmacology
• Nephrology

Background:

• Carbapenem antibiotics, including ertapenem, are associated with neurotoxicity, typically presenting as seizures, encephalopathy, or hallucinations.
• Ertapenem-induced neurotoxicity is most frequently observed in patients with end-stage renal disease (eGFR <30 mL/min/1.73 m²).

Observation:

• A middle-aged male patient with acute kidney injury and a baseline eGFR of 30-59 mL/min/1.73 m² developed delirium and visual hallucinations on day 7 of intravenous ertapenem treatment for empyema.
• The patient's neurological symptoms worsened, necessitating intensive care unit transfer and intubation.
• No improvement in mental status was noted after discontinuing other potential causative medications.

Findings:

• Cessation of ertapenem resulted in rapid improvement of the patient's mental status, with extubation within 24 hours and discharge the following day.
• This case suggests ertapenem-induced encephalopathy can occur in patients with moderate renal impairment (eGFR 30-59 mL/min/1.73 m²), not exclusively in those with end-stage renal disease.
• The rapid and complete resolution of symptoms upon ertapenem withdrawal strongly supports an iatrogenic cause.

Implications:

• Clinicians should consider ertapenem-induced neurotoxicity in patients with moderate renal impairment presenting with altered mental status, even in the absence of seizures.
• Early recognition and discontinuation of ertapenem may prevent severe neurological complications and facilitate prompt recovery.
• Further research is warranted to understand the mechanisms and risk factors for non-seizure neurotoxicity associated with ertapenem in patients with varying degrees of renal function.