Antibiotic Treatment for PJI May Put Patients at High Risk of Acute Kidney Injury
Acute kidney injury (AKI) occurred in nearly 20% of patients who underwent surgery with implantation of an antibiotic-loaded spacer and administration of intravenous (IV) antibiotics for the treatment of deep periprosthetic joint infection (PJI) after total knee arthroplasty (TKA), according to a study from Mayo Clinic. Patients with preexisting chronic kidney disease (CKD) were at particularly high risk of AKI.
Deep PJI is a devastating complication of failed TKA. The most common treatment is 2-stage exchange arthroplasty, in which an antibiotic-loaded bone cement (ALBC) spacer is often used to deliver high doses of antibiotics directly and continuously to the site of the infection.
However, there is a risk that high doses of antibiotics from the spacers, in addition to IV antibiotics, may result in a toxic effect on the kidneys. This toxicity could contribute to AKI, a serious complication marked by a sudden decline in kidney function. Orthopaedic surgeons have little evidence about the risk of AKI related to ALBC spacers and IV antibiotics, and even less evidence regarding the long-term outcomes of patients who develop AKI.
For the study published online ahead of print by The Journal of Bone & Joint Surgery, researchers analyzed the rates, risk factors, and outcomes of AKI in 424 TKA patients who had undergone 2-stage exchange arthroplasty with ALBC spacers and IV antibiotics for chronic PJIs between 2000 and 2017 at Mayo Clinic. Before surgery, 15% of patients had preexisting CKD.
Overall, 19% of patients developed AKI while the ALBC spacers were in place and IV antibiotics were administered. Patients with preexisting CKD were significantly more likely to develop AKI than patients without preexisting CKD: 45% versus 14%, respectively. After adjusting for other factors, patients with CKD were 5 times more likely to develop AKI (odds ratio 5.0).
The study identified several risk factors for AKI, including high doses of antibiotics used in the ALBC spacers, especially the commonly used antibiotics vancomycin and aminoglycoside. Certain factors linked to reduced blood flow to the kidneys, including high blood pressure, low blood volume, and atrial fibrillation (a heart rhythm disorder), also predicted an increased risk of AKI. Diabetes was another important risk factor.
Most patients who developed AKI regained kidney function. However, at an average of 6 years postoperatively, 8 patients had developed CKD while 4 were on dialysis.
Acute kidney injury is a relatively common complication of many medical conditions and procedures, including orthopaedic surgery and heart surgery. This study provides new evidence on AKI in a large series of patients treated for infected TKA at a single medical center.
The findings highlight the particularly high risk of AKI among patients with preexisting CKD. The researchers emphasize the importance of screening to identify patients with possible decreases in kidney function before 2-stage exchange arthroplasty.
The study also draws attention to the risk of AKI related to toxicity from ALBC spacers and IV antibiotics. The researchers have taken steps to limit the doses of certain antibiotics used in spacers. However, they said, “While higher antibiotic doses in ALBC spacers can lead to AKIs, these doses are also a crucial factor for infection eradication.”
Dagneaux L, Limberg AK, Osmon DR, Leung N, Berry DJ, Abdel MP. Acute kidney injury when treating periprosthetic joint infections after total knee arthroplasties with antibiotic-loaded spacers: incidence, risks, and outcomes. J Bone Joint Surg Am. 2021 Mar 29. doi: 10.2106/JBJS.20.01825. Online ahead of print.