Safety of cefepime: a new extended-spectrum parenteral cephalosporin

Potential Role of Therapeutic Drug Monitoring in Preventing Antibiotic-Induced Neuropsychiatric Disorders: A Narrative Review

BACKGROUND

Neuropsychiatric toxicity is a common adverse effect of antibiotics. Advanced age, renal insufficiency, high drug doses, and prolonged therapy are relevant risk factors, suggesting that this event might be caused due to the accumulation of antibiotics in the central nervous system. In this review, the authors aimed to evaluate the potential role of therapeutic drug monitoring in identifying patients at risk of antibiotic-induced neuropsychiatric toxicity.

METHODS

A MEDLINE PubMed search was conducted for articles published between January 1990 and December 2024, matching the terms "pharmacokinetics" or "therapeutic drug monitoring" with "antibiotics" (including individual drug classes) and "neurotoxicity" (including synonyms). Additional studies were identified from the reference lists of retrieved articles.

RESULTS

Significant associations have been reported between plasma concentrations of some beta-lactam antibiotics (ceftazidime, cefepime, piperacillin, and meropenem) or linezolid and drug-induced central nervous system adverse events (such as seizures, encephalopathy, peripheral neuropathy, and optic neuropathy). Safety thresholds of plasma concentrations have been proposed for these drugs.

CONCLUSIONS

Consistent data on the associations between plasma drug concentrations and neuropsychiatric disorders are available only for some antibiotics, whereas for others, there are few and often inconsistent data, hindering the establishment of therapeutic drug monitoring-based safety thresholds for these antibiotics.

Cefepime-induced neurotoxicity: systematic review

BACKGROUND

Cefepime-induced neurotoxicity (CIN) has been well acknowledged among clinicians, although there are no clear diagnostic criteria or specific laboratory testing to help with its diagnosis. We aimed to summarize the existing evidence regarding CIN and provide future agendas for research.

METHODS

Following the PRISMA Extension for Scoping Reviews, we searched MEDLINE and Embase for all peer-reviewed articles using keywords including 'cefepime', 'neurotoxicity', 'encephalopathy' and 'seizure', from their inception to 20 January 2022.

RESULTS

We included 92 articles, including 23 observational studies and 69 cases from case reports and case series, in the systematic review. Among 119 patients with CIN, 23.5% were in the ICU at the time of diagnosis and nearly 90% of the cases showed renal dysfunction.Cefepime overdoses were described in 41%. The median latency period of developing CIN from cefepime initiation was 4 days, and about 12% developed CIN during empirical treatment. CIN patients commonly manifested altered mental status (93%), myoclonus (37%) and non-convulsive seizure epilepticus (28%). A serum cefepime trough level of >20 mg/L would put patients at risk for CIN. CIN-related symptoms were ameliorated in 97.5% by dose reduction or discontinuation of cefepime, with median time to improvement of 3 days. No CIN-associated deaths were reported.

CONCLUSIONS

This systematic review summarizes the current evidence and characteristics of CIN. In the current situation where there are no CIN diagnostic criteria and the drug monitoring platform is not routinely available, candidates for cefepime should be carefully selected. Also, based on these findings, it needs to be appropriately dosed to avoid the development of CIN.

Clinical Pharmacokinetics and Pharmacodynamics of Cefepime

Cefepime is a broad-spectrum fourth-generation cephalosporin with activity against Gram-positive and Gram-negative pathogens. It is generally administered as an infusion over 30-60 min or as a prolonged infusion with infusion times from 3 h to continuous administration. Cefepime is widely distributed in biological fluids and tissues with an average volume of distribution of ~ 0.2 L/kg in healthy adults with normal renal function. Protein binding is relatively low (20%), and elimination is mainly renal. About 85% of the dose is excreted unchanged in the urine, with an elimination half-life of 2-2.3 h. The pharmacokinetics of cefepime is altered under certain pathophysiological conditions, resulting in high inter-individual variability in cefepime volume of distribution and clearance, which poses challenges for population dosing approaches. Consequently, therapeutic drug monitoring of cefepime may be beneficial in certain patients including those who are critically ill, have life-threatening infections, or are infected with more resistant pathogens. Cefepime is generally safe and efficacious, with a goal exposure target of 70% time of the free drug concentration over the minimum inhibitory concentration for clinical efficacy. In recent years, reports of neurotoxicity have increased, specifically in patients with impaired renal function. This review summarizes the pharmacokinetics, pharmacodynamics, and toxicodynamics of cefepime contemporarily in the setting of increasing cefepime exposures. We explore the potential benefits of extended or continuous infusions and therapeutic drug monitoring in special populations.

Acute Toxicity and Triphasic Waves-The Example of Cefepime

PURPOSE

Triphasic waves (TWs) have been associated with a host of medication toxicities, and cefepime has emerged recently as a frequently encountered offending agent. This investigation aims to evaluate cefepime-induced encephalopathy and to report the associated clinical, EEG expression with TWs, and the radiologic findings.

METHODS

A retrospective multicenter observational study examining adult patients with cefepime-induced encephalopathy with generalized periodic discharges on either routine or continuous EEG between January 2014 and January 2020. Clinical, electrographic, and radiologic data were collected. Patients in whom cefepime was not the sole causative factor for their encephalopathy were excluded.

RESULTS

Twenty-seven patients with cefepime-induced encephalopathy marked by generalized periodic discharges with triphasic morphology were identified at both centers, whereas no patients were presenting with generalized periodic discharges without TWs. Patients had a median age of 63 years (interquartile range, 56-73). Fifty-six percent of the cohort (15 patients) were <65 years of age. Eighteen patients (67%) had either acute or chronic kidney impairment (either acute kidney injury or chronic kidney disease or both), whereas 81% had preexisting white matter disease on brain imaging. Of these, 14 patients (51%) were classified as either moderate or severe. In the majority of the patients, TWs were either state-dependent or stimulus-sensitive, and in one third of them presented only as stimulus-induced pattern. All patients improved with discontinuation of cefepime.

CONCLUSIONS

Cefepime toxicity should be considered in the differential diagnosis in encephalopathic patients with TWs. The presence of preexisting white matter disease in these patients should heighten the degree of suspicion, especially in younger patients and patients without renal dysfunction.

Cefepime Neurotoxicity in a Patient With Acute Tubular Necrosis

Neurotoxicity is a rare side effect of Cefepime use. Cefepime can cross the blood-brain barrier and can be neurotoxic by competitive albeit weak antagonism of the gamma-aminobutyric acid complex. It is cleared by the kidneys which puts individuals with renal impairment at risk of side effects. We describe a case of Cefepime neurotoxicity in the context of nephrotoxicity secondary to the use of other drugs.

Jerky Movement with Ceftazidime: A Case of Ceftazidime-Induced Neurotoxicity with a Review of the Literature

Neurotoxicity manifested as confusion and seizures has been recognized as a side effect of multiple cephalosporins including ceftazidime. Renal impairment and inappropriate dosing are the most common contributors to the development of neurological abnormalities in patients receiving these antibiotics. The presence of baseline neurological abnormalities likely contributes to the frequency of these adverse events. Here, we present a case of a 78-year-old man that developed altered mental status and myoclonic movement after initiation of ceftazidime in the setting of mild renal dysfunction. Resolution of clinical picture was evident after 48 hours of discontinuation of the antibiotic without additional interventions.

Dosing Cefepime for Renal Function Does Not Completely Prevent Neurotoxicity in a Patient With Kidney Transplant

Dosing cefepime for renal function does not completely prevent neurotoxicity in a kidney transplant patient. Cefepime neurotoxicity has been reported primarily among patients with renal insufficiency who received standard doses of the antibiotic. We report a case of nonconvulsive status epilepticus from dose-adjusted cefepime in a kidney transplant patient. The timing of symptoms along with clinical and electroencephalographic improvement after discontinuation of cefepime was critical to the diagnosis. Whether we should adjust the dose of cefepime differently in a patient with transplanted kidney to prevent neurotoxicity is unknown.

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.

Neurological Adverse Effects Attributable to β-Lactam Antibiotics: A Literature Review

β-lactam antibiotics are commonly prescribed antibiotic drugs. To describe the clinical characteristics, risk markers and outcomes of β-lactam antibiotic-induced neurological adverse effects, we performed a general literature review to provide updated clinical data about the most used β-lactam antibiotics. For selected drugs in each class available in France (ticarcillin, piperacillin, temocillin, ceftazidime, cefepime, cefpirome, ceftaroline, ceftobiprole, ceftolozane, ertapenem and aztreonam), a systematic literature review was performed up to April 2016 via an electronic search on PubMed. Articles that reported original data, written in French, Spanish, Portuguese or English, with available individual data for patients with neurological symptoms (such as seizure, disturbed vigilance, confusional state, myoclonia, localising signs, and/or hallucinations) after the introduction of a β-lactam antibiotic were included. The neurological adverse effects of piperacillin and ertapenem are often described as seizures and hallucinations (>50 and 25% of cases, respectively). Antibiotic treatment is often adapted to renal function (>70%), and underlying brain abnormalities are seen in one in four to one in three cases. By contrast, the neurological adverse drug reactions of ceftazidime and cefepime often include abnormal movements but few hallucinations and seizures. These reactions are associated with renal insufficiency (>80%) and doses are rarely adapted to renal function. Otherwise, it appears that monobactams do not have serious neurological adverse drug reactions and that valproic acid and carbapenem combinations should be avoided. The onset of disturbed vigilance, myoclonus, and/or seizure in a patient taking β-lactam antibiotics, especially if associated with renal insufficiency or underlying brain abnormalities, should lead physicians to suspect adverse drug reactions and to consider changes in antibacterial therapy.

Characterizing Cefepime Neurotoxicity: A Systematic Review

Neurotoxicity due to cefepime has not been well characterized. We performed a systematic review of the literature and included 5 additional cases from our center. Of the 198 cases found, the mean age was 67 years and 87% of patients had renal dysfunction. The most common clinical features were diminished level of consciousness (80%), disorientation/agitation (47%), and myoclonus (40%). It is worth noting that nonconvulsive status epilepticus was relatively common with 31% of cases, whereas only 11% had convulsive seizures. Single-center estimate of incidence was 1 in 480 courses of cefepime. Cefepime neurotoxicity should be considered in older patients with renal dysfunction and new onset encephalopathy, especially if concurrent myoclonus is present. More work is needed to prospectively assess incidence and outcomes related to cefepime neurotoxicity.

Cefepime-induced neurotoxicity in a pediatric patient on chronic hemodialysis: a case report

Impaired renal function increases the risk for cefepime-induced neurotoxicity. Symptoms include disorientation, myoclonus, status epilepticus, ataxia, gait disturbance, coma, and death. A high index of suspicion and early recognition of symptoms can minimize the risk of progression of symptoms to permanent neurologic impairment or death.

Complications associated with antibiotic administration: neurological adverse events and interference with antiepileptic drugs

Antibiotic use is associated with toxic effects involving the peripheral and central nervous systems and it may interfere with antiepileptic drugs, causing significant variations in their serum levels and activity. Prompt identification of neurological complications during antibiotic therapy is important in order to make appropriate modifications to medication. Characteristics of the drug and the patient, including age and underlying diseases, may favour these complications. The main aim of this study was to review the neurological adverse events that may follow antibiotic administration, the mechanisms that cause them, and the possibility of prevention and treatment. Moreover, the interference of antibiotics with serum levels and the activity of antiepileptic drugs are discussed. The results demonstrate that antibiotic-associated adverse events involving the nervous system are relatively uncommon and are only rarely severe and irreversible, although neurotoxicity has been reported for several antibiotics. Moreover, for patients receiving antiepileptic drugs, monitoring of drug serum levels to avoid the risk of toxicity or inadequate therapy is mandatory during antibiotic treatment. Areas for future research include the effects of combined antibiotic therapies as well as multiple antiepileptic drugs in study populations with an adequate sample size, including neonates and infants, patients with pharmacoresistant epilepsy and elderly patients.

Prognosis of neurologic complications in critical illness

Neurologic complications of critical illness require extensive clinical and neurophysiologic evaluation to establish a reliable prognosis. Many sequelae of intensive care unit (ICU) treatment, such as delirium and ICU-acquired weakness, although highly associated with adverse outcomes, are less suitable for prognostication, but should rather prompt clinicians to seek previously unnoticed persisting underlying illnesses. Prognostication can be confounded by drug administration particularly because its clearance is abnormal in critical illness. Some neurological complications are severe, and can last for months or years after discharge from ICU. The most important ethical aspects regarding neurologic complications in critically ill patients are prevention, recognition, and identification, and prevention of self-fulfilling prophecies. This chapter summarizes the tool of prognostication of major neurological complications of critical illness.

Cefepime-induced encephalopathy in end-stage renal disease patients

OBJECTIVES

Impaired renal function is a risk factor for cefepime (CFPM)-induced encephalopathy (CFPMIE) in patients treated with CFPM; dose-titration to renal function is recommended to prevent CFPMIE. However, available evidence on the incidence of CFPMIE or preventive efficacy of dose adjustment against CFPMIE in end-stage renal disease (ESRD) patients is limited.

METHODS

Single-centre, retrospective observational study. We reviewed consecutive in-hospital adult patients treated with adjusted-dose of CFPM in the period between September 2012 and September 2016, and assessed the CFPMIE in ESRD patients treated with adjusted-dose of CFPM.

RESULTS

Out of 422 eligible patients, 6 patients (1.4%) were diagnosed with CFPMIE. The incidence of CFPMIE in ESRD patients was 7.5% (5/67). Among ESRD patients, pre-existing central nervous system (CNS) morbidity was significantly associated with the risk of CFPMIE. CFPMIE occurred in ESRD patients regardless of daily dose, and even with 0.5g/day of CFPM.

CONCLUSIONS

Pre-existing CNS morbidity may be associated with an increased risk of CFPMIE in ESRD patients. No significant association was observed between CFPM dose and incidence of CFPMIE in ESRD patients, and future investigation on the safer dose-adjustment strategy in ESRD patients is required for achieving balance between successful infectious treatment and reducing CFPMIE.

A Randomized, Prospective Study of Pediatric Patients With Community-acquired Pneumonia Treated With Ceftaroline Versus Ceftriaxone

BACKGROUND

Community-acquired bacterial pneumonia (CABP) remains a major infection among children, despite the use of pneumococcal vaccination. Ceftaroline fosamil is a broad-spectrum cephalosporin antibiotic with activity against many bacteria, including Streptococcus pneumoniae (both penicillin-nonsusceptible and multidrug-resistant strains) and Staphylococcus aureus (including methicillin-resistant S. aureus). This article describes the safety, tolerability, and effectiveness of ceftaroline fosamil in the treatment of pediatric patients hospitalized with CABP, from a randomized, active-controlled, observer-blinded clinical study (registration number NCT01530763).

METHODS

Pediatric patients were stratified into 4 age cohorts and randomized (3:1) to receive either intravenous ceftaroline fosamil or ceftriaxone, with optional oral switch for a total treatment duration of 5-14 days. Enrollment was planned for 160 patients. Data collected included demographics, infection characteristics and pathogens. Treatment-emergent adverse events, clinical outcomes, and microbiologic responses were assessed.

RESULTS

Ceftaroline fosamil was well tolerated. Similar percentages of patients in the ceftaroline fosamil (55/121; 45%) and ceftriaxone (18/39; 46%) groups reported treatment-emergent adverse events. Coombs seroconversion was observed in 17% of patients in the ceftaroline fosamil group; however, no evidence of hemolytic anemia or hemolysis was found. No deaths were reported during the study. Ceftaroline fosamil had similar effectiveness to ceftriaxone, with high clinical cure rates at test-of-cure in the modified intent-to-treat population (94/107; 88% and 32/36; 89%, respectively). Three documented S. aureus infections were successfully treated in the ceftaroline group, including one caused by methicillin-resistant S. aureus.

CONCLUSIONS

The results of this study suggest that ceftaroline fosamil may be an important treatment option for pediatric patients hospitalized with CABP.

Cefepime-induced encephalopathy in patients with haematological malignancies: clinical features and risk factors

BACKGROUND

Cefepime is an antibiotic that is widely used in patients with haematological malignancies (HM). Although its use has been reported to be associated with encephalopathy, only case reports or small case series have been reported so far.

PATIENTS AND METHODS

We conducted a retrospective cohort study of 243 patients with HM treated with cefepime at our hospital between August 2011 and May 2013. We also investigated the clinical features of patients with cefepime-induced encephalopathy (CIE).

RESULTS

Among 243 HM patients treated with cefepime, 10 were diagnosed with CIE, indicating a cumulative incidence of approximately 4.1%. The median creatinine level on commencement of treatment was 2.13 mg/dl (range 0.60-19.85) and the median initial dose of cefepime was 4.0 g/day (range 1.0-6.0). The median time between commencement of treatment and symptoms was 4.0 days (range 2-5). The most common clinical manifestations were decreased level of consciousness and myoclonus. Symptoms resolved fully in all patients. Univariate analyses showed that impaired renal function (creatinine clearance (CLCr) < 30 ml/min, acute renal failure, and chronic dialysis) was significantly associated with the development of CIE (univariate p < 0.0001, p = 0.020, and p = 0.0025, respectively). Receiver operating characteristic (ROC) analysis demonstrated that the threshold levels of creatinine, CLCr, and estimated glomerular filtration rate for CIE were 1.22 mg/dl, 22.96 ml/min, and 43.9 ml/min/1.73 m(2), respectively.

CONCLUSIONS

This study indicated that the development of CIE is associated with severely impaired renal function in patients with HM.

Epileptogenic drugs: a systematic review

A wide range of substances, including drugs and illicit compounds, increase the risk of epileptic seizures. In this systematic review, the authors address the issue of the epileptogenic potential of marketed drugs, with the aims of providing criteria for the assessment of the cause-effect relationship between drug exposure and the risk of seizures; and to identify the compounds better fulfilling the requirements of an epileptogenic drug. Finding a correlation between drug exposure and occurrence of seizures does not necessarily establish a causal association. In light of the available evidence, even with these limitations, some conclusive remarks can be made on the epileptogenic potential of some active principles. Drugs with high epileptogenic potential include meperidine, sevoflurane, clozapine, phenothiazines and cyclosporine. Drugs with intermediate epileptogenic potential include propofol, maprotiline, tricyclic antidepressants and chlorambucil. Drugs with low epileptogenic potential include fluorquinolones, carbapenems, bupropion and iodinated contrast media. Drugs with minimal or inconclusive epileptogenic potential include interferon alpha.

The use of cefepime for treating AmpC β-lactamase-producing Enterobacteriaceae

BACKGROUND

 AmpC β-lactamase-producing organisms are associated with significant morbidity and mortality. Induction of resistance to third-generation cephalosporins after exposure to these agents complicates treatment options and carbapenems are considered optimal therapy. The role of cefepime, however, remains unclear. Our objective was to compare clinical outcomes for patients receiving cefepime compared with meropenem for invasive infections caused by organisms expressing AmpC β-lactamases.

METHODS

 Hospitalized patients with blood, bronchoalveolar lavage, or intra-abdominal fluid cultures growing Enterobacter spp, Serratia spp, or Citrobacter spp were evaluated using the cefotetan-boronic acid disk test and the cefotetan-cloxacillin Etest to identify organisms with AmpC β-lactamase production from February 2010 to January 2011. In patients with organisms hyperproducing AmpC β-lactamases (positive by both methods), clinical outcomes for patients receiving cefepime or meropenem therapy were compared. To minimize the possibility of treatment selection bias, 1:1 nearest neighbor propensity score matching was performed prior to regression analysis.

RESULTS

 Of 399 patients meeting eligibility criteria, 96 (24%) had confirmed infections with AmpC β-lactamase-producing organisms. Propensity score matching of patients infected with AmpC β-lactamase-positive organisms treated with cefepime or meropenem yielded 32 well-balanced patient pairs with no difference in 30-day mortality (odds ratio, 0.63; 95% confidence interval [CI], .23-2.11; P = .36) or length of hospital stay after infection (relative risk, 0.96; 95% CI, .79-1.26; P = .56) between the 2 groups.

CONCLUSIONS

 Cefepime may be a reasonable option for the treatment of invasive infections due to AmpC β-lactamase-producing organisms, particularly when adequate source control is achieved.

Cefepime

Cefepime (Maxipime), Maxcef, Cepimax, Cepimex, Axepim, a parenteral fourth-generation cephalosporin, is active against many organisms causative in pneumonia. Cefepime has in vitro activity against Gram-positive organisms including Staphylococcus aureus and penicillin-sensitive, -intermediate and -resistant Streptococcus pneumoniae similar to that of cefotaxime and ceftriaxone. Cefepime also has good activity against Gram-negative organisms, including Pseudomonas aeruginosa, similar to that of ceftazidime. Importantly, cefepime is stable against many of the common plasmid- and chromosome-mediated beta-lactamases and is a poor inducer of AmpC beta-lactamases. As a result, it retains activity against Enterobacteriaceae that are resistant to third-generation cephalosporins, such as derepressed mutants of Enterobacter spp. Cefepime may be hydrolyzed by the extended-spectrum beta-lactamases produced by some members of the Enterobacteriaceae, but to a lesser extent than the third-generation cephalosporins. Monotherapy with cefepime 1 or 2g, usually administered intravenously twice daily, was as effective for clinical and bacteriological response as ceftazidime, ceftriaxone or cefotaxime monotherapy (1 or 2g two or three times daily) in a number of randomized, clinical trials in hospitalized adult, or less commonly, pediatric, patients with generally moderate to severe community-acquired or nosocomial pneumonia. More limited data indicated that monotherapy with cefepime 2g three times daily was also as effective in treating patients with nosocomial pneumonia as imipenem/cilostatin 0.5g four times daily, and when combined with amikacin, cefepime was as effective as ceftazidime plus amikacin. Patients with pneumonia who failed to respond to previous antibacterial therapy with penicillins or other cephalosporins responded to treatment with cefepime. Cefepime is generally well tolerated, with a tolerability profile similar to those of other parenteral cephalosporins. In clinical trials, the majority of adverse events experienced by cefepime recipients were mild to moderate and reversible. The most common adverse events with a causal relationship to cefepime reported in clinical trials included rash and diarrhea. Other, less common, adverse events included pruritus, urticaria, nausea, vomiting oral candidiasis, colitis, headache, fever, erythema and vaginitis.

CONCLUSION

Cefepime is an established and generally well tolerated parenteral drug with a broad spectrum of antibacterial activity which, when administered twice daily, provides coverage of most of the pathogens that may be causative in pneumonia. In randomized clinical trials in hospitalized patients with generally moderate to severe community-acquired or nosocomial pneumonia, cefepime monotherapy exhibited good clinical and bacteriological efficacy. Cefepime may become a preferred antibacterial agent for infections caused by Enterobacter spp. With prudent use in order to prevent the emergence of resistant organisms, cefepime will continue to be a suitable option for the empiric treatment of pneumonia.

Cefepime neurotoxicity in patients with renal insufficiency

Cefepime is a fourth-generation cephalosporin that is active against both gram-positive and gram-negative organisms. It is administered parenterally for the treatment of severe infections. Approximately 85% of the drug is excreted unchanged by the kidneys. Neurotoxicity in patients with renal failure who are treated with cefepime has been reported sporadically. We report on two senile patients with renal impairment who developed neurotoxicity including lethal outcome after treatment with cefepime.

Newer beta-lactam antibiotics: doripenem, ceftobiprole, ceftaroline, and cefepime

This article reviews the new beta-lactam (β-lactam) antibiotics doripenem, ceftobiprole, and ceftaroline. It covers pharmacokinetic and pharmacodynamic properties, dosing, in vitro activities, safety, and clinical trial results. Doripenem (Doribax) has been approved by the US Food and Drug Administration (FDA) for the treatment of complicated intra-abdominal and urinary tract infections. Ceftaroline has received FDA approval for the treatment of skin and soft tissue infections and community acquired pneumonia. Ceftobiprole has not received FDA approval. The article also reviews recent data suggesting increased overall mortality with Cefepime (Maxipime) use compared with other beta-lactam antibiotics and the potential risk for neurotoxicity in the setting of renal failure.

Cefepime neurotoxicity despite renal adjusted dosing

Neurotoxicity is a rare side-effect of cefepime. There are previous reports of cefepime neurotoxicity in patients whose dosages were not adjusted for their kidney disease. We report a toxic case of non-convulsive status epilepticus in a patient receiving renally-dosed cefepime. A 70-y-old woman was admitted with febrile neutropenia for which renally-dosed cefepime was started. On day 4 she developed altered mental status with orofacial myokymia. Blood and urine cultures were negative. Cerebrospinal fluid analysis was normal. Head computed tomography and magnetic resonance imaging showed no acute intracranial process. An electroencephalogram showed non-convulsive status epilepticus. Anticonvulsants were started, but she continued to have seizures. At this time, careful review of her medication list with temporal association of symptoms suggested cefepime as a probable cause and the drug was stopped. Within 24 h of discontinuation, her mental status began to improve and returned to baseline in 3 days. Our case illustrates that cefepime toxicity may still occur in patients who are dose-adjusted for renal insufficiency. It also underscores the importance of assessing for additional risk factors like history of stroke and seizures. Because cefepime-induced status epilepticus is completely reversible, prompt recognition and medication discontinuance can prevent further morbidity and mortality.

High cefepime plasma concentrations and neurological toxicity in febrile neutropenic patients with mild impairment of renal function

High-dose cefepime therapy is recommended for febrile neutropenia. Safety issues have been raised in a recent meta-analysis reporting an increased risk of mortality during cefepime therapy. Cefepime-related neurological toxicity has been associated with overdosing due to severe renal dysfunction. This study aimed to investigate the association between cefepime plasma concentrations and neurological toxicity in febrile neutropenic patients. Cefepime trough concentrations (by high-performance liquid chromatography) were retrospectively analyzed for 30 adult febrile neutropenic patients receiving the recommended high-dose regimen (6 g/day for a glomerular filtration rate [GFR] of >50 ml/min). The dose adjustment to renal function was evaluated by the ratio of the cefepime daily dose per 100 ml/min of glomerular filtration. The association between cefepime plasma concentrations and neurological toxicity was assessed on the basis of consistent neurological symptoms and/or signs (by NCI criteria). The median cefepime concentration was 8.7 mg/liter (range, 2.1 to 38 mg/liter) at a median of 4 days (range, 2 to 15 days) after the start of therapy. Neurological toxicity (altered mental status, hallucinations, or myoclonia) was attributed to cefepime in 6/30 (20%) patients (median GFR, 45 ml/min; range, 41 to 65 ml/min) receiving a median dose of 13.2 g/day per 100 ml/min GFR (range, 9.2 to 14.3 g/day per 100 ml/min GFR). Cefepime discontinuation resulted in complete neurological recovery for five patients and improvement for one patient. A multivariate logistic regression model confirmed high cefepime concentrations as an independent predictor of neurological toxicity, with a 50% probability threshold at ≥22 mg/liter (P = 0.05). High cefepime plasma concentrations are associated with neurological toxicity in febrile neutropenic patients with mild renal dysfunction. Careful adherence to normalized dosing per 100 ml/min GFR is crucial. Monitoring of plasma concentrations may contribute to preventing neurological toxicity of high-dose therapy for this life-threatening condition.

Newer beta-lactam antibiotics: doripenem, ceftobiprole, ceftaroline, and cefepime

This article reviews the new beta-lactam (beta-lactam) antibiotics doripenem, ceftobiprole, and ceftaroline. It covers pharmacokinetic and pharmacodynamic properties, dosing, in vitro activities, safety, and clinical trial results. Doripenem (Doribax) has been approved by the US Food and Drug Administration (FDA) for the treatment of complicated intra-abdominal and urinary tract infections. At this writing, ceftobiprole is under review by the FDA for approval based on results of phase 3 clinical trials, whereas at least one phase 3 clinical trial of ceftaroline has been completed. The article also reviews recent data suggesting increased overall mortality with Cefepime (Maxipime) use compared with other beta-lactam antibiotics and the potential risk for neurotoxicity in the setting of renal failure.

Cephalosporin-induced neurotoxicity: clinical manifestations, potential pathogenic mechanisms, and the role of electroencephalographic monitoring

OBJECTIVE

To review the clinical manifestations of cephalosporin-induced neurotoxicity, underlying potential mechanisms, role of electroencephalographic (EEG) monitoring, and management of neurotoxicity.

DATA SOURCES

A PubMed search (1970-May 2008) was conducted using search terms such as cephalosporins, neurotoxicity, seizures, and status epilepticus. The search was not limited to the English language and yielded approximately 187 articles.

STUDY SELECTION AND DATA EXTRACTION

Several case reports and case series were included to outline the salient clinical features of cephalosporin neurotoxicity. Laboratory studies investigating the potential mechanisms were also included. Reports outlining the EEG features of cephalosporin neurotoxicity were included and the role of continuous EEG monitoring was extracted. Finally, management strategies of such neurotoxicity are discussed.

DATA SYNTHESIS

Cephalosporin-induced neurotoxicity may manifest in a variety of clinical presentations, ranging from simple encephalopathy or mental status changes to myoclonus, asterixis, seizures, nonconvulsive status epilepticus, as well as coma. Patients who are elderly, those with renal insufficiency, and those with prior neurologic disease may be particularly prone to the neurotoxic effects. The main mechanism of neurotoxicity appears to involve gamma-aminobutyric acid A receptor inhibition, although other mechanisms may be possible. Cephalosporin neurotoxicity may be associated with a variety of EEG manifestations. Treatment mainly involves withdrawal of the offending drug, in addition to hemodialysis in patients with renal failure, and use of benzodiazepines or other anticonvulsants in patients who develop frank status epilepticus. Neurotoxicity can be prevented in high-risk cases with dosage adjustments and monitoring of serum concentrations.

CONCLUSIONS

Knowledge and awareness of the neurotoxic clinical manifestations, EEG findings, and underlying mechanisms are essential for clinicians in identifying and treating this potentially lethal but reversible complication of cephalosporin therapy. Further studies are needed to determine the most appropriate treatment paradigms for patients who develop status epilepticus as a result of cephalosporins.

The safety of cefepime in the treatment of infection

BACKGROUND

Cefepime is a fourth-generation cephalosporin usually reserved for treating severe nosocomial pneumonia, as well as empirical treatment of febrile neutropenia, uncomplicated and complicated urinary tract infections, uncomplicated skin and skin structure infections, and complicated intra-abdominal infections.

OBJECTIVE

Since reports of neurotoxic effects and of an all-cause mortality higher with cefepime than with comparators have created some concerns regarding its safety, this paper reviews data available in the PubMed database up to December 2007 on cefepime safety.

METHODS

Literature data from PubMed obtained by combining cefepime and safety, or cefepime and clinical trials, were examined.

RESULTS/CONCLUSIONS

Caution in the use of cefepime should be adopted until new evidence on cefepime safety is available.

Cefepime versus ceftazidime: considerations for empirical use in critically ill patients

Sepsis and nosocomial infections continue to be a significant problem in intensive care, contributing heavily to mortality and prolonged hospital stay. Early and appropriate antibiotic therapy is critical for optimising outcomes. However, the emergence of highly resistant bacteria, coupled with reduced development of novel antibiotics, means that there is a real threat of development of untreatable nosocomial infections. Cefepime and ceftazidime are broad-spectrum cephalosporins that are widely used to treat Gram-negative nosocomial infections in critically ill patients. Available data suggest that cefepime may have advantages over ceftazidime owing to a broader spectrum of activity and reduced potential for development of bacterial resistance. However, whether either of these agents is superior can only be determined by a head-to-head study evaluating clinical and bacteriological outcomes. Such a study to determine whether apparent differences translate into clinically relevant differences in outcome is indicated.

Cefepime neurotoxicity: case report, pharmacokinetic considerations, and literature review

A 67-year-old woman with diabetes mellitus, chronic renal insufficiency, and recurrent urinary tract infections experienced encephalopathy and myoclonus while receiving cefepime. The adverse drug event was accompanied by elevated cefepime levels and abnormal electroencephalograms. This syndrome resolved after discontinuation of cefepime. Neurotoxicity is a known but possibly underreported adverse event associated with cefepime in patients with renal impairment who receive relatively excessive doses. Most cases reverse on drug cessation. In patients with renal disease, the maintenance dosage should be reduced and the patient monitored for neurotoxicity. Cefepime toxicity should be suspected whenever a patient receiving the drug experiences a change in mental status or myoclonus.

Safety of Newer Parenteral Antibiotics

Several parenteral antimicrobials have been introduced into clinical practice over the course of the last decade. Some of these agents (e.g., linezolid, daptomycin, and tigecycline) are prototypes of new classes of compounds. In comparative clinical trials, these newer anti-infectives have been shown to be safe and to have low rates of discontinuation by patients. However, long-term use has revealed unique toxicities associated with the use of some of these drugs. The adverse events and potential drug interactions associated with the use of these antibiotics are variable and require familiarity with the safety profile of each drug. It is especially important that clinicians be able to recognize serious adverse events associated with the use of specific drugs, because most of the adverse events can be readily reversed by cessation of therapy.

Neutropenia secundaria a betalactámicos. Una vieja compañera olvidada

Beta-lactam-induced neutropenia has been a well-recognized problem since the initiation of penicillin use. It generally develops following high-dose beta-lactam treatment lasting longer than 10 days, and its frequency rises with increases in the cumulative antibiotic dose. Beta-lactam-induced neutropenia is frequently preceded by fever or rash, which can be considered alarm signs. Unlike neutropenia induced by other nonchemotherapy drugs, beta-lactam-induced neutropenia usually lasts less than 10 days and infrequently causes infectious complications or death. Although any beta-lactam agent can cause neutropenia, recent studies have focused on cases of piperacillin-tazobactam- or cefepime-induced neutropenia; a high incidence of neutropenia has been demonstrated during prolonged treatment with these antibiotics. The apparent contradiction with the results of clinical trials that did not detect this complication is due to the fact that they involved treatments shorter than two weeks. The potential for the development of neutropenia during lengthy intravenous treatment should be borne in mind in the development of new beta-lactams.

Cefepime versus ceftazidime for treatment of pneumonia

Consecutive patients with pneumonia, treated with cefepime (n = 66) or ceftazidime (n = 132), were evaluated in a retrospective, observational study. There was no significant difference between the two treatment groups with respect to age, underlying diseases, acute physical and chronic health evaluation score, intensive care unit admission, presence of sepsis, community or hospital acquisition, causative organism, duration of therapy, death, cure or improvement in infection, adverse events, superinfections, presence of vancomycin-resistant enterococcus (VRE) and resistance to therapy. Post-therapy hospitalization (days) and vancomycin co-administration were significantly lower, and time to vancomycin initiation significantly higher, in the cefepime compared with the ceftazidime group. The results suggest a trend towards less resistance on therapy, less VRE, reduced vancomycin use and shorter post-therapy hospitalization in patients treated with cefepime compared with ceftazidime. The clinical outcomes for hospitalized patients treated for serious pneumonia were similar between the two groups.

Retrospective review of neurotoxicity induced by cefepime and ceftazidime

We reviewed 42 cases of cefepime-induced neurotoxicity and 12 cases of ceftazidime-induced neurotoxicity from the literature and our institution. Clinical characteristics and timing of diagnosis were examined. Common findings were confusion with temporospatial disorientation (96% of patients), myoclonus (33%), and seizures (13%). These neurologic disorders frequently are encountered in uremic and elderly patients, who often are in a confused state when they visit their physician. The risk of delayed diagnosis was greater with cefepime than ceftazidime neurotoxicity. The median interval between symptom onset and diagnosis of cefepime versus ceftazidime neurotoxicity was 5 and 3 days, respectively (p=0.005). Delayed diagnosis of cefepime neurotoxicity may be due to lack of awareness of the adverse effect. Data gathered since these two broad-spectrum antibiotics were first marketed underscore the potential for neurologic adverse events secondary to their administration. Thus, clinicians' awareness must be increased so that the time between symptom onset and diagnosis can be reduced.

Cefepime in the empiric treatment of meningitis in children

BACKGROUND

Because the introduction of extended spectrum cephalosporins into pediatric practice offers a number of choices for treatment, we review efficacy studies of cefepime monotherapy in the treatment of bacterial meningitis in children.

METHODS

Two open, randomized, comparative studies assessed the efficacy of cefepime empiric monotherapy in the treatment of bacterial meningitis in 345 pediatric patients. These studies were conducted in Latin America and compared cefepime (50 mg/kg/dose every 8 h) with either cefotaxime (50 mg/kg/dose every 6 h) or ceftriaxone (50 mg/kg/dose every 12 h). Patients 2 months to 14 years old who had clinical signs and symptoms consistent with a central nervous system infection were enrolled. Efficacy was based on clinical and bacteriologic response.

RESULTS

Integrated results from the Latin American studies indicated a 75% cure rate with cefepime vs. a 78% cure rate with comparator, among evaluable patients. Overall the rate of treatment failure was 12%. Haemophilus influenzae had the highest bacterial eradication rate (97% overall), and rates were comparable in cefepime and comparator arms. Eradication rates for Neisseria meningitidis were equally high in both treatment arms (95% overall), and the eradication rate for Streptococcus pneumoniae was 92% overall. Of the patients with S. pneumoniae isolated during pretreatment (from either cerebrospinal fluid or blood), 11 (16 isolates in total) had their isolates tested against penicillin and all were susceptible. Presence or absence of seizures, level of consciousness, Glasgow Coma Score and duration of signs and symptoms were strong predictors of outcome. Collectively no specific safety concerns were identified.

CONCLUSION

Cefepime represents an important therapeutic option for the empiric treatment of bacterial meningitis in children, based on the good clinical response and bacteriologic eradication rates observed in this review.

The new antibiotics

It is easy to become overwhelmed by the amount of information available on the new antibiotics and difficult to keep abreast of the appropriate indications for each of them. For most patients with community-acquired infections, the first-line agent is usually not one of the newer agents, but a standard regimen, or at times, no antibiotic at all. The development of resistance is likely to parallel the extent to which these agents are prescribed. They should be used only when standard treatment fails, when compliance with treatment is a real and serious issue, or when the patient has a real allergic reaction to the standard regimen.

Status epilepticus associated with cefepime

Cefepime is a fourth-generation cephalosporin widely used for gram-negative sepsis. The authors report two patients in whom nonconvulsive status epilepticus developed while they were on treatment with cefepime for Pseudomonas aeruginosa infection. The status epilepticus resolved completely once the drug was withdrawn. Cefepime therapy can result in status epilepticus, especially if given in higher doses than required.

In vitro evaluation of cefepime and other broad-spectrum beta-lactams for isolates in Malaysia and Singapore medical centers. The Malaysia/Singapore Antimicrobial Resistance Study Group

The degree of activity of several beta-lactam antimicrobial agents was assessed in Malaysia (four medical centers) and Singapore (two medical centers) tested against 570 clinical isolates. The organisms were tested locally by the Etest (AB BIODISK, Solna, Sweden) method, validated by concurrent use of quality assurance strains (94.1% accurate performance overall). Ten groups of bacteria were tested against cefepime, cefpirome, ceftazidime, ceftriaxone, piperacillin/tazobactam, oxacillin, and imipenem. Among the tested Escherichia coli and Klebsiella spp., the occurrence of extended spectrum beta-lactamase-producing phenotypes was 5.6-7.0% and 36.7-38.0%, respectively. These strains remained most susceptible (97.5-100.0%) to cefepime and imipenem. Ceftazidime-resistant Enterobacter spp. (21.4% resistant), Citrobacter spp. (15.0%), indole-positive Proteus spp. (6.0%), and Serratia spp. (9.7%) were not resistant to cefepime, and only one strain was resistant to imipenem. Imipenem was generally most potent against non-fermentative Gram-negative bacilli such as Acinetobacter spp. and Pseudomonas aeruginosa. All tested beta-lactams were active against the oxacillin-susceptible staphylococci, except ceftazidime (MIC90, 12 micrograms/mL; 63.2-84.8% susceptibility rates). Overall spectrums of activity (rank by % resistance) favored imipenem (3.5%) > cefepime (7.7%) > cefpirome (8.9%) > piperacillin/tazobactam (13.2%) > ceftriaxone (14.7%) > ceftazidime (16.9%). No significant differences in resistance patterns were noted between monitored nations, and these results indicate emerging, elevated rates of resistance versus the studied broad-spectrum beta-lactams in Malaysia and Singapore. Results provide benchmark data for future studies using quantitative methods to determine antimicrobial resistance in these geographic areas.