Periarticular Penetration of Cefazolin and Clindamycin in Second Stage Revision Arthroplasty of the Hip

Study Overview
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Brief Summary
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To prevent periprosthetic joint infection (PJI), optimal penetration of antibiotics into the joint-space is needed. In revision arthroplasty, the incidence of PJI is increased compared to primary arthroplasty. In this study, the penetration of antibiotic agents into the synovial fluid and bone will be analyzed. The concentration of antibiotics will be related tot the to the susceptibility (minimal inhibitory concentration; MIC-90) of microorganisms that frequently cause PJI.

Detailed Description
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Periprosthetic joint infection (PJI) is a feared complication of joint replacement, with an incidence of 0.5-1% after primary joint replacement and 3-5% after revision arthroplasty. For orthopaedic surgery involving a prosthesis, the administration of systemic antibiotic prophylaxis is strongly recommended to prevent PJI. Cefazolin is widely used as agent of choice in surgical antibiotic prophylaxis. Previous studies, all performed in patients undergoing primary joint replacement, demonstrated that the concentration of cefazolin in bone and synovial fluid was dose-dependent and exceeds the MIC90 for methicillin susceptible Staphylococcus aureus (MSSA), when given as 1 to 4 gram single dose shortly before incision. When a PJI is already present, clindamycin is used as treatment option in PJI caused by staphylococci (when combined with rifampicin) or cutibacteria. A limited number of studies have been performed to analyse the penetration of clindamycin into bone. These studies showed that clindamycin penetrates well into the bone and concentrations exceeded the MIC90 for MSSA. No studies have been performed to analyse the penetration of antibiotic agents into the periarticular tissue in patients who will undergo revision arthroplasty. In revision arthroplasty a foreign body (prosthesis) is in situ and periarticular tissue condition can be compromised due to previous surgical procedures and the presence of bone reaction to the prosthesis. It is not known whether the difference in PJI incidence after primary and revision arthroplasty may be explained by different penetration of the surgical antibiotic prophylaxis. The aim of this explorative study is to analyse the penetration of cefazolin and clindamycin into synovial fluid and bone and whether the concentration of the agents exceeds the MIC90 for micro-organisms frequently causing PJI.

Official Title
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Periarticular Penetration of Cefazolin and Clindamycin in Second Stage Revision Arthroplasty of the Hip

Conditions
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PJI, Bone and Joint Infection, Pharmacokinetics

Intervention / Treatment
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* Drug: sampling blood
* Drug: Sampling synovial fluid
* Drug: Sampling bone tissue


Participation Criteria
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Eligibility Criteria
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Inclusion Criteria: Age 16 years or older. Scheduled second stage revision arthroplasty (reimplantation) of the hip prosthesis during clindamycin 600mg three times a day orally for PJI, started at least 3 days before reimplantation (steady state). Exclusion Criteria: Antibiotic prophylaxis other than cefazolin 2000mg i.v. Cefazolin use within 4 days previous to the reimplantation, other than the single dose administration of surgical prophylaxis just before incision. Clindamycin loaded bone cement in situ. BMI more than 35 kg/m2.

Ages Eligible for Study
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Minimum Age: 16 Years

Sexes Eligible for Study
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All

Accepts Healthy Volunteers
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No

Study Plan
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How is the study designed?
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Design Details

Primary Purpose: Prevention
Allocation: Non-Randomized
Intervention Model: Parallel Assignment
Interventional Model Description: This explorative, low intervention study will be conducted in the Radboudumc Nijmegen and Sint Maartenskliniek (SMK) Nijmegen, The Netherlands. Subject will receive the cefazolin antibiotic prophylaxis and clindamycin antibiotic therapy as standard of care. The study interventions will include blood sampling on baseline and perioperative sampling of serum, synovial fluid and bone for the concentration measurements of the antibiotic agents. For every participating subject 3 serum samples, 1 synovial fluid sample and 2 bone samples will be taken for concentration measurement of cefazolin and clindamycin. Samples will be taken at different timepoints during the procedure.
Masking: None (Open Label)


Arms and Interventions

| Participant Group/Arm | Intervention/Treatment |
| --- | --- |
| Other: cefazolin<br>The cefazolin antimicrobial prophylaxis (2000mg single dose intravenously 15-60 minutes before incision) is part of standard of care. | Drug: sampling blood<br>* During the reimplantation, 3 serum samples will be taken at different timepoint during the procedure.<br>Drug: Sampling synovial fluid<br>* During the reimplantation 1 synovial fluid sample will be taken prior to incision.<br>Drug: Sampling bone tissue<br>* During the reimplantation 2 cortical bone samples will be taken at different timepoints during the procedure.<br>|
| Other: Clindamycin<br>The clindamycin (600mg three times daily orally) PJI therapy is part of standard care. | Drug: sampling blood<br>* During the reimplantation, 3 serum samples will be taken at different timepoint during the procedure.<br>Drug: Sampling synovial fluid<br>* During the reimplantation 1 synovial fluid sample will be taken prior to incision.<br>Drug: Sampling bone tissue<br>* During the reimplantation 2 cortical bone samples will be taken at different timepoints during the procedure.<br>|

What is the study measuring?
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Primary Outcome Measures

| Outcome Measure | Measure Description | Time Frame |
| --- | --- | --- |
| penetration cefazolin into synovial fluid | The ratio (%) of the concentration of cefazolin in synovial fluid to serum. | during surgical procedure prior to incision the synovial fluid sample will be taken | 
| penetration cefazolin into bone tissue | The ratio (%) of the concentration of cefazolin in synovial fluid to serum. | during surgical procedure prior to incision the synovial fluid sample will be taken | 
| penetration clindamycin into bone tissue | The ratio (%) of the concentration of cefazolin in bone tissue to serum. | during surgical procedure, directly after opening the joint and before reimplantation of the prosthesis the bone samples will be taken | 

Secondary Outcome Measures

| Outcome Measure | Measure Description | Time Frame |
| --- | --- | --- |
| AUC/MIC90 of cefazolin | The ratio of area under the curve of cefazolin to the minimal inhibitory concentration-90 of microorganisms | sampling during procedure | 
| AUC/MIC90 of clindamycin | The ratio of area under the curve of cefazolin to the minimal inhibitory concentration-90 of microorganisms | sampling during procedure | 
| factors associated with reduced cefazolin concentration | univariable and multivariable (if possible) analysis for factors that are associated with reduced concentration of cefazolin (i.e., BMI, age, ..) | sampling during procedure | 
| factors associated with reduced clindamycin concentration | univariable and multivariable (if possible) analysis for factors that are associated with reduced concentration of cefazolin (i.e., BMI, age, ..) | sampling during procedure |