Successful Treatment of Osteomyelitis From Methicillin-Resistant Staphylococcus Aureus With Ceftaroline

Efficacy of ceftaroline and rifampin, alone or combined, in a rat model of methicillin-resistant Staphylococcus epidermidis osteomyelitis without implant

IMPORTANCE

Methicillin-resistant Staphylococcus epidermidis (MRSE) contributes to a high percentage of orthopedic infections, and their treatment represents a huge challenge. The present study aimed to evaluate the efficacy of ceftaroline alone or combined with rifampin in a rat MRSE osteomyelitis model and the bone penetration of ceftaroline. A ceftaroline monotherapy showed a significant bacterial reduction in infected bones after a 7-day period of treatment. The combination ceftaroline plus rifampin leveraged rifampin's bactericidal activity, shortening the duration of positive culture in infected animals. These results suggest that ceftaroline and rifampin combination therapy could represent a valuable therapeutic option for human MRSE osteomyelitis and deserves further preclinical and clinical evaluation.

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.

DISC: Describing Infections of the Spine treated with Ceftaroline

OBJECTIVES

Infections of the spine lead to considerable morbidity and a high cost to the global healthcare system. Currently, evidence for using ceftaroline, an advanced-generation cephalosporin active against methicillin-resistant Staphylococcus aureus (MRSA), in spine infections is limited.

METHODS

Describing Infections of the Spine treated with Ceftaroline (DISC) is a multicentre, retrospective, cohort study that evaluated ceftaroline for treating spine infections. Patients were included if they were aged ≥18 years, diagnosed with a spine infection and treated with ceftaroline for ≥28 days. A control group was identified with the same inclusion criteria as the study population except they were treated with a comparator antibiotic for ≥28 days.

RESULTS

Thirty-seven patients were included each in the ceftaroline and control groups. MRSA was the most commonly identified pathogen. With no differences between groups in age, sex, race or co-morbidities (with the exception of chronic kidney disease), treatment with ceftaroline led to similar clinical success compared with the control group. Multivariate regression analysis did not show a significant difference between the two groups in terms of clinical success after controlling for other covariates (adjusted odds ratio=1.49; P=0.711). More patients who received ceftaroline were discharged to an extended-care or rehabilitation facility than home compared with controls (81% vs. 54%, respectively; P=0.024). Side effects and toxicities were rare, including one case of eosinophilic pneumonia in the ceftaroline group.

CONCLUSIONS

Ceftaroline appears to be a safe and effective therapy for infections of the spine, including from MRSA.

Successful Treatment of Methicillin-Resistant Staphylococcus aureus Bacteremia with Ceftaroline Fosamil

Objectives

To describe a case of successful treatment of methicillin-resistant Staphylococcus aureus (MRSA) bacteremia with ceftaroline fosamil after failure with vancomycin and daptomycin.

Case Summary

A 53-year-old female with a past medical history of cancer (unknown source/type) and hypothyroidism was admitted to the hospital with cervical and paravertebral abscess with suspected sepsis. In the emergency department (ED), magnetic resonance imaging (MRI) revealed possible spinal abscess and narrowing of the spinal canal. The patient was initiated on vancomycin 1,250 mg (~15 mg/kg) every 12 hours and cefepime 2 g every 8 hours empirically. On hospital day 4, blood and wound cultures revealed MRSA susceptible to vancomycin, but with a vancomycin minimum inhibitory concentration (MIC) of 2. Repeat blood cultures were also positive on hospital days 2 and 4. Per infectious disease team consult, therapy was converted to daptomycin 8 mg/kg/day. Although the patient responded well, acute kidney injury (AKI) on hospital day 15 prompted a change in therapy to ceftaroline fosamil 400 mg intravenous every 8 hours. For the remainder of the hospital stay, blood cultures were negative and white blood cell count was within normal limits. On day 20, the patient was discharged to a long-term care facility for continued ceftaroline treatment.

Discussion

The management of MRSA bacteremia remains challenging due to increasing antimicrobial resistance. Although the standard therapy for serious MRSA infections is vancomycin, treatment failures are becoming common in clinical practice due to increasing MICs (≥2 μg/mL). Other therapies may include daptomycin and off-label treatment with telavancin, quinupristin/dalfopristin, or ceftaroline fosamil. This report describes a patient with paravertebral abscess and MRSA bacteremia failing 3 days of vancomycin therapy due to MIC greater than or equal to 2 μg/mL and persistent bacteremia. Treatment with ceftaroline fosamil was well tolerated and resulted in continued clinical improvement. Based on this case report, ceftaroline fosamil may be a reasonable alternative for invasive MRSA infections.

Conclusions

This case report describes successful treatment of MRSA bacteremia with ceftaroline in a patient who responded poorly to conventional therapy, specifically vancomycin due to an elevated MIC (2 μg/mL).