Ertapenem-associated neurotoxicity in the spinal cord injury (SCI) population: A case series

A Case of Ertapenem-Induced Delirium

Ertapenem is a carbapenem antibiotic that is typically prescribed in cases of moderate-to-severe infections, especially ones involving abscess formation. We describe the case of an 82-year-old gentleman who presented with osteomyelitis and abscess formation who developed delirium after 15 days of ertapenem treatment. The patient experienced delusions, insomnia, agitation, and disorientation. The patient's mental status improved and returned to his baseline within 48 hours of halting ertapenem treatment. A high index of suspicion is required to identify and treat ertapenem-induced delirium. Withdrawal of ertapenem treatment in such cases usually results in a complete resolution of symptoms.

Ertapenem-Induced Neurotoxicity: A Literature Review of Clinical Characteristics and Treatment Outcomes

Background

Neurotoxicity is a rare adverse event for ertapenem. Given the limited evidence, large patient data are needed to aid in the identification and management of this fatal complication. Aim of the review, we summarize the characteristics, risk factors, and treatment of ertapenem-induced neurotoxicity.

Methods

Pubmed, Web of Science, Embase, Cochrane library, Wanfang, CNKI, China VIP database were searched up from 31 October 2001 to 31 December 2022. All articles concerning neurotoxicity induced by ertapenem were included. The retrieved articles were screened by two experienced clinicians by reading the titles, abstracts, and full texts.

Results

A total of 66 patients were included, with a median age of 71.5 years (range 40-92), of whom 45 (68.2%) were male. Twelve patients (18.2%) received irrational doses (exceeding the recommended dose), and 30 patients (45.5%) had chronic renal insufficiency. The median time to symptom onset was 5 (range 1-14). Epileptiform seizures (42.4%), visual hallucinations (36.4%), altered mental status (25.8%), and confusion (22.7%) were the most common symptoms of ertapenem-induced neurotoxicity. Of the 29 patients with reported albumin levels, 25 had serum albumin <3.5 g/dl. Ertapenem was discontinued in 95.5% of patients, and 90.9% recovered completely. Median time to symptom recovery was 7 days (range 1-42) after intervention including antiepileptic administration, or hemodialysis.

Conclusion

Neurotoxicity is a rare adverse event for ertapenem, especially in patients with advanced age, renal insufficiency, pre-existing neurological disease, and hypoalbuminemia. This adverse reaction usually resolves with medication interruption, or antiepileptic administration and hemodialysis.

A case series of confusional states and other neurotoxic effects caused by ertapenem

Ten cases of ertapenem neurotoxicity, mainly confusional states, are described, some of them with fatal outcomes. The majority of patients (90%) had a creatinine clearance (CrCl) < 50 mL/min/1.73m² at some point during treatment and hypoalbuminaemia was always present when ertapenem treatment was started. The pharmacokinetic and pharmacodynamic properties of this carbapenem could favour a different profile, and approved doses can be excessive in some patients with moderate renal failure (CrCl 31-59 mL/min/1.73 m² ). It may be necessary to re-evaluate renal function during treatment and adjust doses or reconsider the adequacy of treatment based on clinical judgement, especially if relevant changes in the CrCl occur (i.e. a reduction to ≤30 mL/min/1.73 m² ) or unexplained behavioural disorders are detected. The onset of the symptoms of ertapenem neurotoxicity can be insidious and go unnoticed, and so a knowledge and early suspicion of confusional states are important to improve the patient prognosis.

Neurological and Psychiatric Adverse Effects of Antimicrobials

Antimicrobials are a widely used class of medications, but several of them are associated with neurological and psychiatric side effects. The exact incidence of neurotoxicity with anti-infectives is unknown, although it is estimated to be < 1%. Neurotoxicity occurs with all classes of antimicrobials, such as antibiotics, antimycobacterials, antivirals, antifungals and antiretrovirals, with side effects ranging from headaches, anxiety and depression to confusion, delirium, psychosis, mania and seizures, among others. It is important to consider these possible side effects to prevent misdiagnosis or delayed treatment as drug withdrawal can be associated with reversibility in most cases. This article highlights the different neurotoxic effects of a range of antimicrobials, discusses proposed mechanisms of onset and offers general management recommendations. The effects of antibiotics on the gut microbiome and how they may ultimately affect cognition is also briefly examined.