CNP EEG Fellow Univeristy of Florida Gainesville, Florida
Rationale: Cefepime is known to cause neurotoxicity. The most common EEG abnormalities described in cefepime induced neurotoxicity (CIN) are triphasic waves, focal sharp waves and periodic discharges; however, those abnormalities are non specific. The objectives of this study are: a) to compare the EEG findings in patients with cefepime trough levels >25 with and without documented CIN, and b) to correlate EEG abnormalities with cefepime trough levels in patients with CIN. Methods: This was a retrospective observational study. Adult patients were included in the study if they received cefepime for ≥ 5 days, had cefepime trough levels >25mcg/ml and had EEG performed during the admission. Patient’s demographic data, medical history, cefepime dosing and renal function were abstracted from the chart. EEG characteristics were grouped according to the American Clinical Neurophysiology society critical care EEG reporting terminology 2014. National cancer institute common terminology criteria for adverse events was used to define CIN (presence of neurologic symptoms and symptom resolution after cefepime discontinuation). Results: A total of 31 patients met the study criteria. Twelve patients met the criteria for CIN. When comparing baseline characteristics, patients with CIN had a greater incidence of acute kidney injury [10(83%) vs 7(37%), p=0.01)] compared to patients without CIN. The incidence of bifrontal predominant generalized periodic discharges (GPDs) with triphasic morphology was significantly higher in patients with CIN (67%) compared to those without CIN (26%) (odds ratio=5.6, 95%, confidence interval=1.23-30.09, p=0.0255). Other common EEG findings including degree of encephalopathy, multifocal sharp waves, generalized rhythmic delta activity (GRDA), and non-convulsive status epilepticus were not significantly different between the two groups.There was no association between serum creatinine levels and EEG abnormalities.In patients withEEG showing GPDs the cefepime trough was higher than in patients without this EEG abnormality (77.3mcg/ml vs 33.5mcg/ml), however this finding did not reach statistical significance. Conclusions: In our study patients with CIN were five times more likely to have bifrontal predominant GPDs with triphasic morphology compared to patients without CIN. This finding may help to guide antibiotic therapy when there is concern for CIN. Cefepime though levels were higher in patients with GPDs compared to patients without this finding; however, no statistical significance was found when comparing both groups. The small sample size may explain the absence of correlation between cefepime blood levels and specific EEG abnormalities. Funding: Please list any funding that was received in support of this abstract.: NA Click here to view image/table
