TY - JOUR

T1 - Rifampicin does not reduce moxifloxacin concentrations at the site of infection and may not improve treatment outcome of a one-stage exchange surgery protocol of implant-associated osteomyelitis lesions in a porcine model

AU - Vittrup, Sofus

AU - Jensen, Louise Kruse

AU - Hartmann, Katrine Top

AU - Aalbæk, Bent

AU - Hanberg, Pelle

AU - Slater, Josefine

AU - Hvistendahl, Magnus Andreas

AU - Stilling, Maiken

AU - Jørgensen, Nis Pedersen

AU - Bue, Mats

N1 - Publisher Copyright: © 2023 Scandinavian Societies for Pathology, Medical Microbiology and Immunology.

PY - 2024

Y1 - 2024

N2 - We aimed to evaluate moxifloxacin steady-state concentrations in infected bone and soft tissue and to explore the additive microbiological and pathological treatment effect of rifampicin to standard moxifloxacin treatment of implant-associated osteomyelitis (IAO). 16 pigs were included. On Day 0, IAO was induced in the proximal tibia using a susceptible Staphylococcus aureus strain. On Day 7, the pigs underwent one-stage exchange surgery of the IAO lesions and were randomized to receive seven days of intravenous antibiotic treatment of either rifampicin combined with moxifloxacin or moxifloxacin monotherapy. On Day 14, microdialysis was applied for continuous sampling (8 h) of moxifloxacin concentrations. Microbiological, macroscopical pathology, and histopathological analyses were performed postmortem. Steady-state moxifloxacin area under the concentration–time curve was lower in the combination therapy group in plasma (total) and subcutaneous tissue compartments (infected and noninfected) (p < 0.04), while no differences were found in bone compartments. No additional treatment effect of rifampicin to moxifloxacin treatment was found (p = 0.57). Conclusive, additive rifampicin treatment does not reduce moxifloxacin concentrations at the infection site. Rifampicin treatment may not be necessary in a one-stage exchange treatment of IAO. However, our sample size and treatment period may have been too small and short to reveal true clinical differences.

AB - We aimed to evaluate moxifloxacin steady-state concentrations in infected bone and soft tissue and to explore the additive microbiological and pathological treatment effect of rifampicin to standard moxifloxacin treatment of implant-associated osteomyelitis (IAO). 16 pigs were included. On Day 0, IAO was induced in the proximal tibia using a susceptible Staphylococcus aureus strain. On Day 7, the pigs underwent one-stage exchange surgery of the IAO lesions and were randomized to receive seven days of intravenous antibiotic treatment of either rifampicin combined with moxifloxacin or moxifloxacin monotherapy. On Day 14, microdialysis was applied for continuous sampling (8 h) of moxifloxacin concentrations. Microbiological, macroscopical pathology, and histopathological analyses were performed postmortem. Steady-state moxifloxacin area under the concentration–time curve was lower in the combination therapy group in plasma (total) and subcutaneous tissue compartments (infected and noninfected) (p < 0.04), while no differences were found in bone compartments. No additional treatment effect of rifampicin to moxifloxacin treatment was found (p = 0.57). Conclusive, additive rifampicin treatment does not reduce moxifloxacin concentrations at the infection site. Rifampicin treatment may not be necessary in a one-stage exchange treatment of IAO. However, our sample size and treatment period may have been too small and short to reveal true clinical differences.

KW - Implant-associated osteomyelitis

KW - microdialysis

KW - moxifloxacin

KW - one-stage exchange

KW - rifampicin

U2 - 10.1111/apm.13371

DO - 10.1111/apm.13371

M3 - Journal article

C2 - 38153297

AN - SCOPUS:85180822054

VL - 132

SP - 198

EP - 209

JO - A P M I S. Acta Pathologica, Microbiologica et Immunologica Scandinavica

JF - A P M I S. Acta Pathologica, Microbiologica et Immunologica Scandinavica

SN - 0903-4641

IS - 3

ER -