Background: Cefepime is a widely used antibiotic. However, it can cause encephalopathy, which has been increasingly described in the literature, occurring mainly in patients with impaired renal function. The primary objective in this study was to measure the incidence of cefepime-induced encephalopathy and determine potential risk factors for its occurrence.
Methods: In the period from February 2005 to February 2006, a prospective cohort study was conducted, which followed 498 patients using cefepime. Other metabolic problems were ruled out for all patients with clinical suspicion of encephalopathy and, when cefepime was the probable cause, electroencephalographic (EEG) tests were performed to assist in the diagnosis, with the first performed during cefepime use and another performed at least 48 hours following drug discontinuation and/or clinical improvement.
Results: Among patients selected for this study (n=498), 5 were diagnosed with cefepime-induced encephalopathy, thus indicating a cumulative incidence of approximately 1% (0.01), 387 had glomerular filtration rate (GFR) >or=60 ml/min and 111 had GFR <60 ml/min. Among the latter, 5 patients developed cefepime-induced encephalopathy. Mean GFR value in patients with encephalopathy (n=5) was 17.20 ml/min (SD +/-10.75 ml/min) and, in patients without encephalopathy (n=106) it was 32.59 ml/min (SD +/-14.89 ml/min) (p=0.025).
Conclusion: The development of cefepime-induced encephalopathy seems to be related to the severity of impairment in glomerular filtration.