Linezolid-induced complex partial seizure in a patient without epilepsy

Linezolid has most commonly been associated with myelosuppression, peripheral neuropathy, optic neuropathy, and serotonin syndrome, particularly in those with prolonged durations of use (>28 days).1Vinh D.C. Rubinstein E. Linezolid: a review of safety and tolerability.J Infect. 2009; 59: S59-S74Abstract Full Text PDF PubMed Scopus (153) Google Scholar, 2US Food and Drug Administration. Linezolid (marketed as Zyvox) Information. Last updated 24 October, 2011. Available at: www.fda.gov/Safety/MedWatch/SafetyInformation/SafetyAlertsforHumanMedical Products/ucm265479.htm (accessed January 15, 2014).Google Scholar Epileptic seizures are extremely rare. The case of an elderly patient without epilepsy who developed complex partial seizures on day 36 of linezolid treatment is reported below. A 68-year-old female was admitted 4 months after an accidental fall due to progressive difficulty walking. Spinal magnetic resonance imaging (MRI) revealed depressed fractures complicated with spondylodiscitis involving the level 10 and 11 thoracic vertebrae. Cultures obtained from the involved bone and soft tissues yielded methicillin-resistant Staphylococcus aureus (MRSA). She had mild leukocytosis and a markedly elevated C-reactive protein (CRP) level, while liver and kidney function were normal. Intravenous linezolid 600 mg every 12 h was initiated. On day 36 of treatment, she developed a 'complex partial seizure', so far unique for her, with eyes fixed and deviated to the left side, unresponsiveness to verbal stimuli, and without concomitant motor autonomic symptoms. This seizure lasted for around 15 min. Results of arterial blood gas and biochemistry analyses obtained soon after the seizure revealed no findings of metabolic acidosis or any electrolyte imbalance, including lactate, sodium, and potassium. No significant findings were detected on cranial MRI, however her awake and sleep electroencephalography (EEG) was compatible with postictal period on day 3 after the seizure. An EEG obtained 35 days after the seizure was essentially normal. A 1-hour sleep EEG was normal. She was taking no concomitant medications that could have contributed to the seizure activity. Linezolid was discontinued immediately and the treatment was switched to intravenous daptomycin 6 mg/kg/day. No antiepileptic treatment was initiated and no more seizures or other neurological findings developed during follow-up. To our knowledge, this is the first case of linezolid-induced seizures in a patient with no known epilepsy.3Shneker B.F. Baylin P.D. Nakhla M.E. Linezolid inducing complex partial status epilepticus in a patient with epilepsy.Neurology. 2009; 72: 378-379Crossref PubMed Scopus (9) Google Scholar, 4Cholongitas E. Karatzi C. Spyrou S. Georgousaki C. Dasenaki M. Linezolid-induced complex partial seizures in a patient with epilepsy.Scand J Infect Dis. 2009; 41: 540-541Crossref PubMed Scopus (7) Google Scholar The long-term use of linezolid may induce an epileptic seizure even in those without epilepsy. Withdrawal of the drug may be sufficient as a measure. Conflict of interest: None declared.