A case of profound neutropenia and agranulocytosis associated with off-label use of ceftaroline

Contemporary pharmacologic treatments of MRSA for hospitalized adults: rationale for vancomycin versus non-vancomycin therapies as first line agents

INTRODUCTION

Methicillin-resistant Staphylococcus aureus (MRSA) remains an important pathogen in the hospital setting and causes significant morbidity and mortality each year. Since the initial discovery over 60 years ago, vancomycin has remained a first-line treatment for many different types of MRSA infections. However, significant concerns related to target attainment and nephrotoxicity have spurred efforts to develop more effective agents in the last two decades.

AREAS COVERED

Newer anti-MRSA antibiotics that have been approved since 2000 include linezolid, daptomycin, and ceftaroline. As clinical evidence has accumulated, these newer agents have become more frequently used, and some are now recommended as co-first-line options (along with vancomycin) in clinical practice guidelines. For this review, a scoping review of the literature was conducted to support our findings and recommendations.

EXPERT OPINION

Vancomycin remains an important standard of care for MRSA infections but is limited with respect to nephrotoxicity and rapid target attainment. Newer agents such as linezolid, daptomycin, and ceftaroline have specific indications for treating different types of MRSA infections; however, newer agents also have unique attributes which require consideration during therapy.

Comparison of Neutropenia Associated with Ceftaroline or Ceftriaxone in Patients Receiving at Least 7 Days of Therapy for Severe Infections

STUDY OBJECTIVE

Ceftarolinefosamil is a cephalosporin with broad clinical utility; however, limited data suggest that prolonged ceftaroline exposure may be associated with neutropenia. The objective was to determine drug and patient factors associated with neutropenia in patients receiving ceftaroline or ceftriaxone for deep-seated infections.

DESIGN

Retrospective, ratio-matched cohort study.

SETTING

Four acute-care hospitals within an urban health care system.

PATIENTS

A total of 176 hospitalized adults who received definitive ceftaroline (44 patients) or ceftriaxone (132 patients) therapy for at least 7 days between January 2013 and April 2017 for any of the following indications: bone and joint infections (BJI), infective endocarditis (IE), or bloodstream infections (BSI).

MEASUREMENTS AND MAIN RESULTS

The primary outcome was development of neutropenia while receiving cephalosporin therapy, defined as an absolute neutrophil count (ANC) <1500 cells/mm3 . Neutropenia severity and patient characteristics were described and compared between the ceftaroline and ceftriaxone groups. The median (interquartile range [IQR]) antibiotic prescription duration was 41 (29-44) days for the ceftaroline group and 40 (28-44) days for the ceftriaxone group (p=0.9). Cephalosporin indications were 112 (64%) BJI, 27 (15%) BSI, 16 (9%) IE, and 21 (12%) multiple infections; ceftaroline was more commonly used in BJI (p=0.03), and ceftriaxone was more commonly used in IE (p=0.01). Neutropenia developed in 16 (9%) patients: 8 (18%) in the ceftaroline group and 8 (6%) in the ceftriaxone group (p=0.03). Median (IQR) onset to neutropenia was 22 (15-28) days, and median (IQR) change in ANC was 2.86 (1.50-4.08) cells/mm3 ; most cases of neutropenia were mild (12 patients [75%]). The median (IQR) time to mild or moderate-severe neutropenia was not significantly different (p=0.68): 22 (14-28) and 22 (21-36) days, respectively. Treatment was discontinued in 4 (25%) patients due to neutropenia. Ceftaroline use was independently associated with neutropenia (adjusted odds ratio 3.2, 95% confidence interval 1.2-10.5) after adjusting for lower body mass index strata (18.5-25 kg/m2 ).

CONCLUSION

Prolonged ceftaroline use was an independent risk factor for developing mild neutropenia. Clinicians should be cognizant of ANC monitoring in scenarios where prolonged ceftaroline courses are prescribed.

Comparison of Adverse Drug Reactions Between Patients Treated With Ceftaroline or Ceftriaxone: A Single-Center, Matched Cohort Study

Background

Little information is available on the relative tolerability of ceftaroline versus other cephalosporins in clinical practice. We sought to compare adverse drug reactions (ADRs) associated with ceftaroline with those associated with ceftriaxone in hospitalized patients.

Materials and Methods

This was a retrospective, single-center matched cohort (according to age, indication, and duration) study of patients treated with ceftaroline or ceftriaxone at the VA St Louis Health Care System between 29 October 2010 and 28 March 2017, to compare rates of ADRs between the agents. Patients included received ≥2 doses of either medication to treat osteomyelitis, acute bacterial skin and skin structure infection, blood stream infection, pneumonia, infective endocarditis, septic arthritis, prosthetic joint infection, or empyema. The primary and secondary outcomes were the composite of any ADR during therapy and any ADR leading to premature discontinuation of therapy. The ADRs evaluated included rash, neutropenia, acute kidney injury, eosinophilia, thrombocytopenia, transaminitis, and hyperbilirubinemia.

Results

After matching, 50 patients per group were included and analyzed. An ADR occurred in 20% (10 of 50) of patients treated with ceftriaxone and 16% (8 of 50) of those treated with ceftaroline (P = .60). Two percent (1 of 50) of those treated with ceftriaxone and 16% (8 of 50) treated with ceftaroline had therapy discontinued owing to an ADR (P = .03). The most common ADR was eosinophilia (3 of 50) in the ceftriaxone group and rash (5 of 50) in the ceftaroline group. Ceftaroline therapy was identified as an independent risk factor for an ADR requiring premature discontinuation (odds ratio, 10.2; 95% confidence interval, 1.19–87.8; P = .03).

Conclusions

Although there was no difference in the rates of ADRs between patients in the ceftriaxone and ceftaroline groups, significantly more ceftaroline-treated patients required premature discontinuation.

Methicillin-resistant Staphylococcus aureus in solid organ transplantation-Guidelines from the American Society of Transplantation Infectious Diseases Community of Practice

These updated guidelines from the American Society of Transplantation Infectious Diseases Community of Practice review the epidemiology, diagnosis, prevention, and management of methicillin-resistant Staphylococcus aureus (MRSA) infections in solid organ transplantation. Despite an increasing armamentarium of antimicrobials active against MRSA, improved diagnostic tools, and overall declining rates of infection, MRSA infections remain a substantial cause of morbidity and mortality in solid organ transplant recipients. Pre- and post-transplant MRSA colonization is a significant risk factor for post-transplant MRSA infection. The preferred initial treatment of MRSA bacteremia remains vancomycin. Hand hygiene, chlorhexidine bathing in the ICU, central-line bundles that focus on reducing unnecessary catheter use, disinfection of patient equipment, and the environment along with antimicrobial stewardship are all aspects of an infection prevention approach to prevent MRSA transmission and decrease healthcare-associated infections.

Ceftaroline-Associated Neutropenia: Case Series and Literature Review of Incidence, Risk Factors, and Outcomes

Ceftaroline is increasingly prescribed for "off-label" indications involving longer durations and higher doses. There have been postmarketing case reports of neutropenia among patients who have received extended durations of ceftaroline, but limited published data currently exist on its incidence and risk factors. We review a total of 37 published cases of ceftaroline-associated neutropenia including cases (n = 4) identified in our health care system. The median time from ceftaroline initiation to development of neutropenia (range) was 25 (8-125) days, with a median duration of neutropenia (range) of 4 (1-16) days. Agranulocytosis (absolute neutrophil count [ANC] nadir < 100 cells/mm³) developed in 49% of cases (n = 18), and there was an ANC nadir of 0 in 27% (n = 10). The overall incidence of neutropenia among cases receiving ceftaroline for ≥7-14 days (range) was 12% (7%-18% per individual study), higher than for comparator antibiotics in the literature. Risk factors for ceftaroline-associated neutropenia varied among studies and remain poorly defined.

Use of Ceftaroline Fosamil in Osteomyelitis: CAPTURE Study Experience

BACKGROUND

Osteomyelitis is often challenging to treat. This analysis examined the clinical experience of patients with gram-positive osteomyelitis treated with ceftaroline fosamil in the phase 4 Clinical Assessment Program and Teflaro® Utilization Registry (CAPTURE) study.

METHODS

Data including patient demographics, past illnesses, risk factors, disease characteristics, antibiotic use, pathogens isolated, and clinical outcome were collected between September 2013 and February 2015 by review of randomly ordered patient charts from participating sites in the United States. Clinical success was defined as discontinuation of ceftaroline fosamil following clinical cure with no further need for antibiotics or clinical improvement with switch to another antibiotic treatment.

RESULTS

A total of 150 patients with gram-positive osteomyelitis were treated with ceftaroline fosamil. Most patients (117/150; 78.0%) were treated with 600 mg ceftaroline fosamil per dose; 143/150 patients (95.3%) received a dose every 12 h. The majority (89/150 patients; 59.3%) had been previously diagnosed with diabetes mellitus or peripheral arterial disease. Osteomyelitis was associated with hardware in 32/150 patients (21.3%). Methicillin-resistant and methicillin-susceptible Staphylococcus aureus (MRSA; MSSA) were the most commonly isolated pathogens, observed in 93/150 (62.0%) and 21/150 (14.0%) patients, respectively. Clinical success with ceftaroline fosamil therapy was observed in 139/150 (92.7%) patients overall, 81/89 (91.0%) patients with diabetes or peripheral arterial disease, and 18/20 (90.0%) patients who had hardware implanted before ceftaroline fosamil therapy (none had hardware removed during therapy). Patients who received prior antibiotic therapy or ceftaroline fosamil as monotherapy experienced clinical success rates of 93.9% (107/114) and 91% (91/100), respectively. Among patients who received concurrent antibiotic therapy, the clinical success rate was 96.0% (48/50). Patients who were infected with MRSA or MSSA had clinical success rates of 92.5% (86/93) and 100% (21/21), respectively. A total of 2/150 (1.3%) patients discontinued ceftaroline fosamil therapy because of adverse events.

CONCLUSIONS

Clinical success rates with ceftaroline fosamil were high in patients with gram-positive osteomyelitis, including those with diabetes or peripheral arterial disease and those with MRSA or MSSA.

Comparative analysis of neutropenia in patients receiving prolonged treatment with ceftaroline

Objectives

Ceftaroline is often used in durations greater than that studied in clinical trials. Several retrospective, non-comparative studies have suggested a higher than anticipated incidence of neutropenia in patients receiving prolonged treatment with ceftaroline. We sought to determine if ceftaroline was associated with neutropenia by comparing the incidence with ceftaroline treatment with treatment with several comparative antibiotics.

Methods

Patients receiving 14 or more consecutive days of treatment with ceftaroline were compared with patients receiving cefazolin, daptomycin, linezolid, nafcillin or vancomycin (control group). The primary outcome was the development of neutropenia. Multivariate logistic regression and propensity score weighting using inverse probability weights with regression adjustment were used to control for confounding variables.

Results

A total of 753 patients were included (53 that received ceftaroline and 700 that received a comparative antibiotic). Ceftaroline was associated with a greater incidence of neutropenia as compared with the control group (17.0% versus 3.9%, P < 0.001). Several covariates were also associated with neutropenia and included younger age, lower baseline absolute neutrophil count, liver disease and bone and joint infections. After controlling for these confounders, receipt of ceftaroline continued to be associated with the development of neutropenia (adjusted OR 3.97, P = 0.003). Analysis after propensity score weighting confirmed this finding.

Conclusions

The results of this study suggest that prolonged treatment with ceftaroline is associated with a greater incidence of neutropenia as compared with other antibiotics that are often used for treatment of staphylococcal infections. Careful monitoring of absolute neutrophil count is recommended in patients receiving >14 days of ceftaroline.

Rate and Incidence of Adverse Reactions Associated With Ceftaroline Exposure: Importance of Cutaneous Manifestations

BACKGROUND

Ceftaroline is a broad-spectrum, methicillin-resistant Staphylococcus aureus (MRSA)-active β-lactam approved for acute bacterial skin and skin structure infections (ABSSSIs) and community-acquired pneumonia. Because of its favorable spectrum and pharmacokinetics, ceftaroline is frequently utilized for infections such as osteomyelitis and endocarditis. Ceftaroline has been associated with neutropenia, but evaluation of other adverse events remains limited.

OBJECTIVE

To describe the rates and types of ceftaroline-associated adverse events and determine if patients' baseline allergies affect the rates of an adverse event.

METHODS

A single-center, retrospective, observational analysis was conducted of all patients who received ceftaroline between November 4, 2011, and March 28, 2017, at the VA Saint Louis Health Care System. The Naranjo algorithm was utilized as a standardized method to evaluate likelihood that the adverse events were caused by ceftaroline therapy. Ceftaroline dose, duration, indication, and baseline allergy information were collected for all patients.

RESULTS

There were 75 patients who received 78 courses of ceftaroline identified for inclusion. The most common indications were osteomyelitis (51.3%) and ABSSSI (16.7%). Overall, 13/75 (17.3%) patients developed an adverse event, and 10/75 (13.3%) required discontinuation of ceftaroline. Rash was the most common adverse reaction and occurred in 7/75 (9.3%) patients, followed by neutropenia in 3/75 (4.0%) patients. There were no differences in baseline allergy characteristics between patients who experienced an adverse reaction to ceftaroline and those who did not.

CONCLUSIONS

When compared with clinical trials, ceftaroline use appears to be associated with an increased rate of overall adverse events, which is driven by cutaneous reactions.

Outcomes of Vancomycin plus a β-Lactam versus Vancomycin Only for Treatment of Methicillin-Resistant Staphylococcus aureus Bacteremia

The objective of this retrospective study was to compare the rates of treatment failure, which was a composite of clinical and microbiologic failure, of patients receiving vancomycin and a β-lactam to those receiving vancomycin only for methicillin-resistant Staphylococcus aureus (MRSA) bacteremia. Patients 16 to 89 years of age with MRSA bacteremia admitted to a university-affiliated hospital from 1 January 2014 to 31 December 2016 were screened for study inclusion. Patients were eligible if they received >48 h of vancomycin and a β-lactam (combination group) or vancomycin only (standard group) within 48 h after bacteremia onset. A total of 182 patients were screened: 47 were included in the standard group, and 63 were in the combination group. The combination group had a higher baseline body mass index (29.2 ± 8.0 kg/m² versus 25.8 ± 7.1 kg/m², P = 0.022), acute physiologic assessment and chronic health evaluation-II (APACHE-II) score (median [interquartile range], 21 [15 to 26] versus 16 [10 to 22], P = 0.003), and incidence of septic shock (31.8% versus 14.9%, P = 0.047). Using multivariate analysis, combination therapy was the only variable that decreased treatment failures (odds ratio [95% confidence interval], 0.337 [0.142 to 0.997]), while vancomycin MIC > 1 mg/liter and male gender increased treatment failures (4.018 [1.297 to 12.444] and 2.971 [1.040 to 8.488], respectively). The 30-day mortality rates (15.0% versus 14.9%, P = 1.000) and the incidence of adverse drug events (19.1% versus 23.4%, P = 0.816) were not statistically different between the combination and standard groups. Combination therapy of vancomycin with a β-lactam led to significantly fewer treatment failures than vancomycin monotherapy for MRSA bacteremia.

In Vitro activity of novel glycopolymer against clinical isolates of multidrug-resistant Staphylococcus aureus

The incidence of multidrug-resistant (MDR) organisms, including methicillin-resistant Staphylococcus aureus (MRSA), is a serious threat to public health. Progress in developing new therapeutics is being outpaced by antibiotic resistance development, and alternative agents that rapidly permeabilize bacteria hold tremendous potential for treating MDR infections. A new class of glycopolymers includes polycationic poly-N (acetyl, arginyl) glucosamine (PAAG) is under development as an alternative to traditional antibiotic strategies to treat MRSA infections. This study demonstrates the antibacterial activity of PAAG against clinical isolates of methicillin and mupirocin-resistant Staphylococcus aureus. Multidrug-resistant S. aureus was rapidly killed by PAAG, which completely eradicated 88% (15/17) of all tested strains (6-log reduction in CFU) in ≤ 12-hours at doses that are non-toxic to mammalian cells. PAAG also sensitized all the clinical MRSA strains (17/17) to oxacillin as demonstrated by the observed reduction in the oxacillin MIC to below the antibiotic resistance breakpoint. The effect of PAAG and standard antibiotics including vancomycin, oxacillin, mupirocin and bacitracin on MRSA permeability was studied by measuring propidium iodide (PI) uptake by bacterial cells. Antimicrobial resistance studies showed that S. aureus developed resistance to PAAG at a rate slower than to mupirocin but similar to bacitracin. PAAG was observed to resensitize drug-resistant S. aureus strains sampled from passage 13 and 20 of the multi-passage resistance study, reducing MICs of mupirocin and bacitracin below their clinical sensitivity breakpoints. This class of bacterial permeabilizing glycopolymers may provide a new tool in the battle against multidrug-resistant bacteria.

Ceftaroline fosamil monotherapy for methicillin-resistant Staphylococcus aureus bacteremia: a comparative clinical outcomes study

OBJECTIVES

Vancomycin is the treatment of choice for methicillin-resistant Staphylococcus aureus (MRSA) bacteremia; however, its use has been subject to scrutiny due to failure in severe infections. Ceftaroline fosamil (CPT-F) is approved for MRSA acute bacterial skin and skin structure infections, but not for bloodstream infections. The clinical outcomes of treatment with CPT-F in patients with MRSA bacteremia were evaluated.

METHODS

Patients diagnosed with MRSA bacteremia at Henry Ford Hospital in Detroit, Michigan, USA, involving isolates with a vancomycin minimum inhibitory concentration ≥1.0mg/l and susceptible in vitro to CPT-F, were systematically reviewed retrospectively. Ceftaroline fosamil-treated patients were matched with at least two vancomycin- and/or one daptomycin-treated control patient based on age-patients age 65 years or greater or less than 65 years of age. Outcomes evaluated included the duration of hospitalization, duration of therapy, adverse events, relapse, hospital readmission, and death.

RESULTS

Thirty consecutive cases of MRSA bacteremia treated with CPT-F during the period May 2011 to June 2013 were identified; these patients were matched to 56 MRSA bacteremia patients treated with vancomycin and 46 MRSA bacteremia patients treated with daptomycin. The primary source of MRSA bacteremia in the cohort treated with CPT-F was endocarditis (n=7, 23%), skin/wound (n=9, 30%), and bone/joint (n=8, 27%). The MRSA bacteremia in those treated with CPT-F was community-acquired in 43% of cases, healthcare-associated in 43%, and hospital-acquired in 13%. The mean length of hospital stay for these patients was 22 days. The overall 30-day mortality rate was 13% (n=4) in CPT-F patients versus 24% (n=11) in daptomycin patients and 11% (n=6) in vancomycin patients (p=0.188).

CONCLUSIONS

CPT-F demonstrated comparable clinical outcomes in MRSA bacteremia patients compared with the other agents, especially as salvage therapy.

Combination Therapy With Vancomycin and Ceftaroline for Refractory Methicillin-resistant Staphylococcus aureus Bacteremia: A Case Series

PURPOSE

Although vancomycin has been the mainstay of therapy for methicillin-resistant Staphylococcus aureus (MRSA) infections, its effectiveness has been challenged. Combination therapy may be used for patients with persistent MRSA bacteremia refractory to initial therapy. Studies have reported in vitro synergy between vancomycin and ceftaroline; however, clinical experience with this therapy is limited. Here, we report our experience with 5 cases of vancomycin-refractory MRSA bacteremia treated with the combination of vancomycin and ceftaroline.

METHODS

Between January 2014 and August 2016, 5 patients were identified who received vancomycin and ceftaroline combination therapy due to persistent bacteremia or deterioration of their clinical status on vancomycin alone (despite a vancomycin MIC within the susceptible range).

FINDINGS

Five patients presented with MRSA bacteremia secondary to endocarditis (n = 2), epidural abscess (n = 2), or left iliopsoas abscess (n = 1). Four of the 5 patients experienced microbiologic cure, and 1 patient transitioned to palliative care.

IMPLICATIONS

This case series serves to describe additional clinical experience with vancomycin and ceftaroline combination therapy. This combination may be considered when vancomycin monotherapy does not lead to microbiological and/or clinical improvement in patients with metastatic MRSA bacteremia. Additional studies are warranted to further define its role in salvage therapy for persistent MRSA bacteremia.

Use of Ceftaroline Fosamil in Children: Review of Current Knowledge and its Application

Ceftaroline is a novel cephalosporin recently approved in children for treatment of acute bacterial skin and soft tissue infections and community-acquired bacterial pneumonia (CABP) caused by methicillin-resistant Staphylococcus aureus, Streptococcus pneumoniae and other susceptible bacteria. With a favorable tolerability profile and efficacy proven in pediatric patients and excellent in vitro activity against resistant Gram-positive and Gram-negative bacteria, ceftaroline may serve as a therapeutic option for polymicrobial infections, CABP caused by penicillin- and ceftriaxone-resistant S. pneumoniae and resistant Gram-positive infections that fail first-line antimicrobial agents. However, limited data are available on tolerability in neonates and infants younger than 2 months of age, and on pharmacokinetic characteristics in children with chronic medical conditions and those with invasive, complicated infections. In this review, the microbiological profile of ceftaroline, its mechanism of action, and pharmacokinetic profile will be presented. Additionally, clinical evidence for use in pediatric patients and proposed place in therapy is discussed.

Outpatient use of ceftaroline fosamil versus vancomycin for osteoarticular infection: a matched cohort study

OBJECTIVES

There are few convenient intravenous options for long-term outpatient treatment of osteoarticular infection (OAI) and limited effectiveness and safety data exist for this off-label use of ceftaroline. The objective of this study was to describe the long-term effectiveness and safety of ceftaroline for the treatment of OAI.

METHODS

This was a matched retrospective cohort study of patients receiving ceftaroline- or vancomycin-based therapy for OAI in the outpatient setting. Patients were matched according to infection subtype, anatomical site and microbiology. The primary endpoint was 180 day infection-related readmission (IRR). Secondary endpoints included all-cause readmission, time-to-IRR and adverse event incidence.

RESULTS

The final matched cohort consisted of 50 ceftaroline-treated patients and 50 vancomycin-treated patients. The IRR incidence was 22% for ceftaroline patients and 30% for vancomycin patients; OR = 0.66 (95% CI = 0.27-1.62; P = 0.362). There was no significant difference between groups in all-cause readmission or time-to-IRR. Attributable adverse event incidences were 24% and 18% for ceftaroline and vancomycin, respectively. Rash (10%) and nausea (6%) were the most common ceftaroline adverse events, while acute kidney injury (6%) and rash (4%) were the most common vancomycin adverse events.

CONCLUSIONS

Attributable readmission and adverse events were common among patients treated with outpatient intravenous antimicrobials for OAI. This study found no appreciable difference in effectiveness or tolerability between ceftaroline- or vancomycin-treated patients. Although further research will be important to delineate the role of ceftaroline in the management of OAI, data derived from this study may aid clinicians in determining therapy when limited options exist.

High incidence of neutropenia in patients with prolonged ceftaroline exposure

OBJECTIVES

We sought to determine the rate of incident neutropenia and identify potential clinical factors associated with incident neutropenia among patients treated with long courses of ceftaroline.

METHODS

We retrospectively identified adult patients who received ceftaroline for ≥7 days consecutively at two large academic medical centres in Boston, USA between November 2010 and March 2015. Clinical characteristics (age, gender, medication allergies, baseline renal function, duration of ceftaroline exposure, total daily ceftaroline dose, body mass-adjusted ceftaroline dose and development of rash and neutropenia) were recorded and the rate of incident neutropenia was calculated. The Naranjo probability scale was used to assess whether ceftaroline exposure was associated with neutropenia. We assessed whether clinical factors were associated with neutropenia.

RESULTS

The overall rate of incident neutropenia was 10%-14% with ≥2 weeks and 21% with ≥3 weeks of ceftaroline exposure. The median duration of ceftaroline exposure [26 days (IQR 22-44; range 13-68) in patients who developed neutropenia and 15 days (IQR 9-29; range 7-64) in patients without neutropenia] was associated with incident neutropenia (P = 0.048). The median total number of ceftaroline doses received [63 (IQR 44-126; range 36-198) by neutropenic patients and 32 (IQR 22-63; range 14-180) by non-neutropenic patients] was also associated with incident neutropenia (P = 0.023).

CONCLUSIONS

The overall rate of neutropenia was high and associated with duration of ceftaroline exposure and total number of doses received. Close laboratory monitoring is warranted with long-term ceftaroline use.

Adverse Drug Reactions Associated with Ceftaroline Use: A 2-Center Retrospective Cohort

BACKGROUND

Ceftaroline fosamil is a cephalosporin approved for treating skin and soft tissue infections (SSTIs), including those caused by methicillin-resistant Staphylococcus aureus and community-acquired pneumonia (CAP).

OBJECTIVES

We aimed to study ceftaroline use and associated adverse drug reactions (ADRs), including hypersensitivity reactions (HSRs), among inpatients.

METHODS

We performed a retrospective electronic health record review of inpatients from Massachusetts General Hospital and Brigham and Women's Hospital who received ceftaroline between May 2012 and February 2015. ADRs diagnosed by clinical providers during the course of clinical care were subsequently verified and classified. Risk factors for ADRs were identified.

RESULTS

Among 96 patients (median age, 57 years; 54% females) who received a median of 28 (interquartile range, 6-63) ceftaroline doses, 54% were being treated for methicillin-resistant Staphylococcus aureus and treatment indications other than SSTI and CAP comprised 59% of care. There were 31 ADRs observed in 20 (21%) patients; hematologic (n = 15) and cutaneous (n = 9) findings were most common. Observed HSRs included rash with mucosal lesions (n = 1), rash with skin desquamation (n = 1), and possible organ-specific HSRs (n = 2). Patients who suffered an ADR received more doses of ceftaroline (median, 46 vs 21; P = .013). There was no increased risk of ceftaroline ADR among patients with reported beta-lactam allergy history (P > .5).

CONCLUSIONS

Ceftaroline is used to treat a range of infections beyond SSTI and CAP. We observed a high rate of ADRs from ceftaroline, including signs of severe HSRs. More data are needed to understand the frequency and predictors of ceftaroline ADRs and HSRs.

Neutropenia Associated with Long-Term Ceftaroline Use

Ceftaroline is a fifth-generation cephalosporin with potent antimicrobial activity against Gram-positive and Gram-negative pathogens. Neutropenia is a rare serious adverse event for the class of cephalosporins; however, we observed several cases of severe neutropenia in our outpatient infectious disease practice believed to be associated with ceftaroline use. The aim of this study was to determine the incidence of neutropenia among patients receiving ceftaroline therapy for more than 7 days. We conducted a retrospective cohort analysis of patients admitted to an 800-bed regional medical center between June 2012 and December 2014 who received ceftaroline for more than 7 days to assess the incidence of developing clinically significant neutropenia. Demographic and patient care data points as well as underlying admitting and chronic diagnoses were retrospectively collected from the medical record. Clinically significant neutropenia was defined as an absolute neutrophil count (ANC) less than 1,500 cells/mm(3). Analysis was performed to determine the incidence, severity, and outcome of neutropenia following ceftaroline administration. A total of 39 patients were included in the cohort. The median duration of therapy was 27 days. Seven patients (18%) developed neutropenia while on ceftaroline therapy. Four (10%) of the neutropenic patients had an ANC of <500 cells/mm(3). The median first neutropenic day was day 17, with the median ANC nadir of 432 cells/mm(3) on day 24. We determined that extended ceftaroline infusion is associated with the development of neutropenia. We recommend obtaining a complete blood count (CBC) with differential at the onset of therapy and weekly thereafter. Should the ANC fall below 2,500 cells/mm(3), then twice-weekly CBCs should be monitored for the duration of ceftaroline therapy, and therapy should be discontinued if the ANC falls to 1,500 cells/mm(3) or less.

Agranulocytosis with ceftaroline high-dose monotherapy or combination therapy with clindamycin

INTRODUCTION

The only clinically available cephalosporin with in vivo and in vitro activity against methicillin-resistant Staphylococcus aureus is ceftaroline, which is approved for the treatment of soft tissue infection and community-acquired pneumonia in doses of 600 mg intravenously every 12 hours for 2 weeks or less. However, many clinicians use ceftaroline to treat more serious infections and dose more frequently (every 8 hours) for longer periods of time.

METHODS

A retrospective medication safety assessment was performed at two centers where agranulocytosis was observed in four patients (two at each center) who were treated with ceftaroline. The cases were reviewed by the treating physicians for common features, and the frequency of agranulocytosis was calculated based on the total number of treated patients.

RESULTS

We report four cases of agranulocytosis associated with ceftaroline use, highlighted by prolonged use (more than 14 days) and 8-hour dosing intervals or 12-hour dosing intervals with concomitant clindamycin therapy. When ceftaroline (600 mg every 12 hours) and clindamycin (900 mg every 8 hours) were coadministered for more than 2 weeks, the frequency of agranulocytosis was 18% (2 of 18 patients treated). When ceftaroline alone was administered for more than 2 weeks at 600 mg every 8 hours, agranulocytosis occurred in 5.4% (2 of 37 treated patients). No cases of ceftaroline-related agranulocytosis were seen that did not have these features. In these patients, granulocyte-colony stimulating factor therapy usually resulted in rapid myeloid recovery.

CONCLUSIONS

Clinicians should have a heightened awareness of agranulocytosis when using ceftaroline in such settings and monitor complete blood counts at least once/week.