The Effects of Gout Following total Knee Arthroplasty: A Retrospective Analysis.

BACKGROUND: The prevalence of gout is increasing along with the number of total knee arthroplasties (TKA) performed annually. The purpose of this study was to evaluate the incidence of gout following TKA in patients who had a previous history of gout and to determine if it is associated with an increased rate of postoperative joint complications. METHODS: Patients who did and did not have a preoperative diagnosis of gout and underwent a primary TKA were identified from a national database. The gout patients were matched 1:1 to patients who did not have gout and rates of postoperative gout diagnoses within 2 years of surgery were compared. Complication rates at mean 1 and 2 years were then compared for both patient cohorts using multivariable logistic regressions. A total of 17,463 patients with a prior diagnosis of gout were matched with 17,463 controls. RESULTS: There were 53.8% of patients who had previous gout and had a recurrence of gout within 2 years versus 3.6% of controls (Odds Ratios [OR]: 30.86). At mean 1-year, patients who had gout were significantly more likely to experience prosthetic joint infections (PJIs) and revision procedures. At mean 2 years, gout patients were at increased risk of prosthetic loosening, PJI, revision, and incision and debridement procedures. CONCLUSION: This study suggests that patients who had a prior diagnosis of gout are significantly more likely to experience recurrent episodes of gout after TKA. Gout attacks after TKA are associated with an increase in the rate of joint complications. LEVEL OF EVIDENCE: Level III.

Economic Burden of Patient-Reported Penicillin Allergy on Total Hip and Total Knee Arthroplasty.

INTRODUCTION: Self-reported penicillin allergies in patients undergoing total joint arthroplasty often results in the use of second-line prophylactic antibiotics. A higher risk of prosthetic joint infection (PJI) is associated with suboptimal antibiotics vs first generation cephalosporins, which have historically been grouped with other beta-lactam antibiotics such as penicillin for potential allergic reactions. This study evaluates the economic burden of self-reported penicillin allergies in total joint arthroplasty (TJA). METHODS: Data from studies reporting true incidence of IgE-mediated penicillin allergies, infection-free survivorship of TJA, and cost of PJI attributed to use of second-line antibiotics were obtained. Projected cost of preoperative penicillin allergy testing and potentially avoidable PJI associated with second-line antibiotic usage were calculated. This was compared with projected cost of PJI in the current state to estimate cost savings. RESULTS: Implementation of preoperative penicillin allergy testing leads to a potential savings of nearly $37 million to payors in the first year based on 1-year survivorship. This savings increases to $411.6 million over a 10-year span and $1.18 billion over a 20-year span. CONCLUSION: Preoperative penicillin allergy testing or risk stratification via thorough history should be implemented as standard of care for patients with self-reported penicillin allergies before TJA and would result in decreased cost of PJI.