Effect of polymyxin B-containing regimens on renal function for the treatment of carbapenem-resistant Enterobacteriacea mediastinitis

ABSTRACT A retrospective cohort study, were evaluated: polymyxin B plus aminoglycosides or polymyxin B plus other antibiotics. Any degree of acute kidney injury occurred in 26 (86.6%) patients. The median time to acute kidney injury was 6.0 (95% CI 3-14) days in the polymyxin-aminoglycoside containing regimen group, against 27.0 (95% CI 6-42) days in the polymyxin with other antimicrobial combinations group (p = 0.03). Polymyxin B with aminoglycosides group progressed faster to any degree of renal dysfunction.

Effect of polymyxin B-containing regimens on renal function for the treatment of carbapenem-resistant Enterobacteriacea mediastinitis.

A retrospective cohort study, were evaluated: polymyxin B plus aminoglycosides or polymyxin B plus other antibiotics. Any degree of acute kidney injury occurred in 26 (86.6%) patients. The median time to acute kidney injury was 6.0 (95% CI 3-14) days in the polymyxin-aminoglycoside containing regimen group, against 27.0 (95% CI 6-42) days in the polymyxin with other antimicrobial combinations group (p=0.03). Polymyxin B with aminoglycosides group progressed faster to any degree of renal dysfunction.

In Vitro Assessment of Combined Polymyxin B and Minocycline Therapy against Klebsiella pneumoniae Carbapenemase (KPC)-Producing K. pneumoniae.

The multidrug resistance profiles of Klebsiella pneumoniae carbapenemase (KPC) producers have led to increased clinical polymyxin use. Combination therapy with polymyxins may improve treatment outcomes, but it is uncertain which combinations are most effective. Clinical successes with intravenous minocycline-based combination treatments have been reported for infections caused by carbapenemase-producing bacteria. The objective of this study was to evaluate the in vitro activity of polymyxin B and minocycline combination therapy against six KPC-2-producing K. pneumoniae isolates (minocycline MIC range, 2 to 32 mg/liter). Polymyxin B monotherapy (0.5, 1, 2, 4, and 16 mg/liter) resulted in a rapid reduction of up to 6 log in bactericidal activity followed by regrowth by 24 h. Minocycline monotherapy (1, 2, 4, 8, and 16 mg/liter) showed no reduction of activity of >1.34 log against all isolates, although concentrations of 8 and 16 mg/liter prolonged the time to regrowth. When the therapies were used in combination, rapid bactericidal activity was followed by slower regrowth, with synergy (60 of 120 combinations at 24 h, 19 of 120 combinations at 48 h) and additivity (43 of 120 combinations at 24 h, 44 of 120 combinations at 48 h) against all isolates. The extent of killing was greatest against the more susceptible polymyxin B isolates (MICs of ≤0.5 mg/liter) regardless of the minocycline MIC. The pharmacodynamic activity of combined polymyxin B-minocycline therapy against KPC-producing K. pneumoniae is dependent on polymyxin B susceptibility. Further in vitro and animal studies must be performed to fully evaluate the efficacy of this drug combination.

Clinical evolution of mediastinitis in patients undergoing adjuvant hyperbaric oxygen therapy after coronary artery bypass surgery.

OBJECTIVE: To evaluate the use of hyperbaric oxygen therapy as an adjunctive treatment in mediastinitis after coronary artery bypass surgery. METHODS: This is a retrospective descriptive study, performed between October 2010 and February 2012. Hyperbaric oxygen therapy was indicated in difficult clinical management cases despite antibiotic therapy. RESULTS: We identified 18 patients with mediastinitis during the study period. Thirty three microorganisms were isolated, and polymicrobial infection was present in 11 cases. Enterobacteriaceae were the most prevalent pathogens and six were multi-resistant agents. There was only 1 hospital death, 7 months after the oxygen therapy caused by sepsis, unrelated to hyperbaric oxygen therapy. This treatment was well-tolerated. CONCLUSION: The initial data showed favorable clinical outcomes.

Evolução clínica de pacientes com mediastinite pós-cirurgia de revascularização miocárdica submetidos à oxigenoterapia hiperbárica como terapia adjuvante / Clinical evolution of mediastinitis in patients undergoing adjuvant hyperbaric oxygen therapy after coronary artery bypass surgery

OBJETIVO: Avaliação da utilização de oxigenoterapia hiperbárica, como tratamento adjuvante, em casos de mediastinite, em pós-operatório de cirurgia de revascularização miocárdica. MÉTODOS: Estudo descritivo retrospectivo, no período entre outubro de 2010 e fevereiro de 2012. A oxigenoterapia hiperbárica foi indicada nos casos de difícil manejo clínico a despeito da antibioticoterapia. RESULTADOS: Identificaram-se 18 pacientes com mediastinite, nos quais 33 microrganismos foram isolados, estando a infecção polimicrobiana presente em 11 casos. Enterobactérias foram os germes mais prevalentes e seis agentes multirresistentes. Ocorreu 1 óbito, na evolução, 7 meses após o término da oxigenoterapia, por septicemia, não relacionado à terapêutica. O tratamento foi bem tolerado. CONCLUSÃO: Os resultados clínicos iniciais foram favoráveis.

OBJECTIVE: To evaluate the use of hyperbaric oxygen therapy as an adjunctive treatment in mediastinitis after coronary artery bypass surgery. METHODS: This is a retrospective descriptive study, performed between October 2010 and February 2012. Hyperbaric oxygen therapy was indicated in difficult clinical management cases despite antibiotic therapy. RESULTS: We identified 18 patients with mediastinitis during the study period. Thirty three microorganisms were isolated, and polymicrobial infection was present in 11 cases. Enterobacteriaceae were the most prevalent pathogens and six were multi-resistant agents. There was only 1 hospital death, 7 months after the oxygen therapy caused by sepsis, unrelated to hyperbaric oxygen therapy. This treatment was well-tolerated. CONCLUSION: The initial data showed favorable clinical outcomes.