MRSA, Staph, Staff, Mersa, Methicillin Resistant Staphylococcus Aureus Symptoms & Treatment

German Study Suggest Linezolid Cost Effective

Link: HighWire Press -- Medline Abstract.

This study used a decision analytic model approach to evaluate the cost-effectiveness of linezolid versus vancomycin in the empirical treatment of complicated skin and soft-tissue infection (cSSTI) due to suspected methicillin-resistant Staphylococcus aureus (MRSA) from the German hospital and health care system perspective. Clinical probabilities were obtained from trial data, resource utilisation and MRSA prevalence rates were obtained through German physician interviews, and costs from published sources were applied to resource units. Outcomes included total cost/patient and cure. The estimated first-line cure rate for linezolid-treated patients was 90.1% versus 85.5% for vancomycin; total cure rates after two lines of treatment were 98.4% and 98.1%, respectively. Average total cost/episode was 8,232

for linezolid versus 9,206

for vancomycin. The model outcomes were sensitive to changes in length of stay (LOS), isolation days, rate of confirmed MRSA and price of linezolid. Linezolid was expected to result in a shorter intravenous treatment duration and shorter LOS that offset its higher acquisition cost versus vancomycin in cSSTI in Germany.

Linezolid resistance emerging

Link: An outbreak of colonization with linezolid-resistant Staphylococcus epidermidis in an intensive therapy unit -- Kelly et al., 10.1093/jac/dkn043 -- Journal of Antimicrobial Chemotherapy.

To report an outbreak of colonization with linezolid-resistant Staphylococcus epidermidis in an intensive therapy unit (ITU). Methods: An outbreak of colonization with linezolid-resistant S. epidermidis affecting 16 patients in an ITU was investigated using PFGE. Environmental and staff screening was carried out as part of the investigation. Usage of linezolid in the hospital and in the ITU was reviewed. Resistant strains were screened for the presence of the G2576T mutation using PCR-RFLP genotyping. The interventions made to control the outbreak were restriction of linezolid prescription and specific infection control measures, including isolation of colonized patients and increased environmental cleaning. Results: Linezolid-resistant S. epidermidis strains from the 16 colonized patients were genetically related. The same strain was also cultured from environmental samples in the ITU. An increase in linezolid usage in the hospital and in the ITU occurred in the 6 months prior to the emergence of the resistant strain. Infection control measures and restriction of linezolid prescription controlled the outbreak. All resistant isolates contained the G2576T mutation. Conclusions: An outbreak of colonization with linezolid-resistant S. epidermidis occurred in the ITU in our institution. The resistant strain colonized the environment and probably spread from patient to patient. The outbreak was associated with an increase in the linezolid usage in the ITU and in the institution as a whole. Restriction of linezolid usage and infection control measures were introduced to control the outbreak. The emergence of linezolid resistance in S. epidermidis has implications for the use of linezolid as a therapeutic agent.

Linezolid more effective

Link: HighWire Press -- Medline Abstract.

At EOT, clinical success rates in the MRSA microbiologically evaluable population were 62.9% and 50.0% for the linezolid and vancomycin groups, respectively; and microbiological eradication rates were 79.0% and 30.0% in the two groups, respectively (P < 0.0001). At FU, the clinical success rates were 36.7% for both groups and the microbiological eradication rates were 46.8% and 36.7%, respectively. Reversible anaemia (13%) and thrombocytopenia (19%) were reported more frequently in linezolid patients; laboratory analysis showed mild decrease in platelet counts with full recovery by FU. The mean platelet count in linezolid patients with thrombocytopenia was 101 000/mm(3). Significantly low platelet counts (<50 000/mm(3)) were observed more frequently in patients receiving vancomycin than in linezolid patients (6% versus 3%). Mean changes in haemoglobin levels between the two groups were not different. Conclusions Linezolid is as effective as vancomycin for the treatment of MRSA infections and may be more effective than vancomycin in achieving microbiological eradication. Haematological adverse events were reported more frequently in linezolid-treated patients; analysis of laboratory data showed a mild reversible trend towards lower platelet counts.

Linezolid versus vancomycin for MRSA treatment

Link: Linezolid versus vancomycin for the treatment of infections caused by methicillin-resistant Staphylococcus aureus in Japan -- Kohno et al., 10.1093/jac/dkm369 -- Journal of Antimicrobial Chemotherapy.

Reversible anaemia (13%) and thrombocytopenia (19%) were reported more frequently in linezolid patients; laboratory analysis showed mild decrease in platelet counts with full recovery by FU. The mean platelet count in linezolid patients with thrombocytopenia was 101 000/mm3. Significantly low platelet counts (<50 000/mm3) were observed more frequently in patients receiving vancomycin than in linezolid patients (6% versus 3%). Mean changes in haemoglobin levels between the two groups were not different. Conclusions: Linezolid is as effective as vancomycin for the treatment of MRSA infections and may be more effective than vancomycin in achieving microbiological eradication. Haematological adverse events were reported more frequently in linezolid-treated patients; analysis of laboratory data showed a mild reversible trend towards lower platelet counts.

Evaluating Linezolid

Link: HighWire Press -- Medline Abstract.

During 1999-2005 we treated 15 patients with linezolid for relevant infections of locomotion apparatus (7 cases with endoprosthesis infection, 5x osteomyelitis and 3x another infection). With the exception of one case the antibiotic therapy was always combined with appropriate surgical intervention. Average period of linezolid administration was 26 d; linezolid was applied from the beginning intravenously on average for 10 d, and then orally for 16 d (average). There were no undesirable effects in the file. Success rate reached 86.6%. MRSA strains were proved by standard methods: growth on Mueller-Hinton agar with increased concentration of NaCl and 2 mg/L of oxacilline, and measuring inhibitory zones around cephoxitine disk. The sensitivity to other antibiotics was specified by disk-diffusion test; that to linezolid was verified by E-test. Linezolid represents a medical reserve for the treatment of multiresistant Gram-positive infections or for emergencies, when allergy onset, high toxicity risk, intolerance, etc. do not allow to use other, in vitro effective, antibiotics.

Linezolid helps diabetics when vancomycin fails

Link: Linezolid tissue penetration and serum activity against strains of methicillin-resistant Staphylococcus aureus with reduced vancomycin susceptibility in diabetic patients with foot infections -- Stein et al., 10.1093/jac/dkm271 -- Journal of Antimicrobial Chemotherapy.

Results: Linezolid concentrations in tissue were found to be 51% (range, 18% to 78%) of simultaneous serum concentrations. Rapid (1 h) and prolonged (12 h) inhibitory activity (titres ≥ 1:2) was observed for linezolid against each of the study isolates. Furthermore, bactericidal activity (titres ≥ 1:2) was observed for at least 6 h (50% of the dosing interval) against four of these five strains. Conclusions: These findings suggest that linezolid could be effective in the treatment of multidrug-resistant MRSA even when concentrations at the infection site are diminished due to impaired blood flow.

Linezolid resistance - what might cause it

Link: HighWire Press -- Medline Abstract.

The results demonstrate that PK/PD considerations are important in optimizing both antibacterial activity and development of resistance to linezolid. The potential for resistance development appears higher when a constant concentration is maintained in the vicinity of the MIC of the bacteria.

Linezolid - Expensive but cheaper?

Link: HighWire Press -- Medline Abstract.

Treatment with oral linezolid during hospitalization and after discharge (scenario 3) was associated with lower costs ($8923, $11 479, and $12 481, respectively) and greater effectiveness (0.867, 0.787, and 0.707, respectively) compared to the IV vancomycin/oral linezolid switch (scenario 2) and IV vancomycin (scenario 1), so it dominated the latter options in the base-case, incremental cost-effectiveness analysis ($10 292, $14 486, and $17 653 per MRSA SSI cure, respectively). Furthermore, the sensitivity analysis demonstrated that the IV vancomycin/oral linezolid (scenario 2) option would be the expected cost-effective choice only if the length of hospitalization for this scenario was less than 6 days or if the probability of cure with oral linezolid (scenario 3) was less than or equal to 0.72; otherwise, the oral linezolid option was dominant. A major limitation of this study is the utilization of probability estimates from both institutional and published research sources. Additionally, the success rates for linezolid were obtained from one relatively small randomized, open-label trial. CONCLUSIONS: Using decision-analytic modeling, treatment with oral linezolid during hospitalization and after discharge is expected to be the most cost-effective approach for treating SSIs caused by MRSA.

Linezolid - costly but effective, reduces other costs

Link: HighWire Press -- Medline Abstract.

     RESULTS: Costs were higher for nonsurviving patients compared with surviving patients. Estimated median daily billed treatment charges were $2888 for linezolid and $2993 for vancomycin. Based on Monte Carlo simulations, the respective 95% CIs were $2671 to $3106 and $2615 to $3372. Using mean treatment durations of 11.3 and 10.7 days, respectively, we obtained expected total hospitalization charges of $32,636 for linezolid treatment (95% CI, $30,182-$35,098), compared with $32,024 for vancomycin treatment (95% CI, $27,978-$36,078). The ICER for linezolid per life saved was $3600. CONCLUSIONS: The higher acquisition cost of linezolid was almost completely offset by improved survival and a reduction in health care costs associated with improved survival. As a result, linezolid was almost cost-neutral compared with vancomycin in the treatment of NP caused by MRSA.

More Linezolid reactions emerge

Link: HighWire Press -- Medline Abstract.

    We present a case of severe optic neuropathy following linezolid treatment, which led to complete irreversible blindness, in a patient with progressive muscular dystrophy, treated with linezolid for 16 days for methicillin-resistant Staphylococcus aureus (MRSA) pneumonia. Interruption of antibiotic therapy did not lead to remission of ocular symptoms. Administration of linezolid may lead to severe neuropathy even in the case of short-term treatment.