Comparable Outcome Of Culture-negative And Culture-positive Periprosthetic Hip Joint Infection For Patients Undergoing Two-stage Revision

Objective: Periprosthetic joint infection(PJI)is a terrible complication after total hip arthroplasty(THA)and the rate of PJI is increasing.It is associated with high levels of morbidity,mortality and expense.Clinical feature of culture-negative PJI(CN-PJI)has not been well studied till now.Guidelines and protocols exist for the management of culture-positive patients.Managing culture-negative patients with a PJI poses a greater challenge to surgeons and the wider multidisciplinary team as clear guidance is lacking.The objective of this study is to explore clinical characters and possible risk factors of culture negative periprosthetic joint infection patients.Long-term clinical results and treatment outcome were compared in two patient groups undergoing two-stage revision arthroplasty using an antibiotic-impregnated cement spacer.Methods: We retrospectively reviewed Consecutive patients who underwent a two-stage revision THA for chronic infection between 2012 and2018 from the database.According to the diagnostic criteria of PJI,Two groups including CN-PJI group and(Culture-positive PJI,CP-PJI)were identified for this study.Information such as the demographics,laboratory findings,microbiological data,clinical outcomes,the time interval between antibiotic-impregnated cement spacer insertion and revision arthroplasty,andrecurrence of infection were analyzed.All patients went through two-stage revision.Patients were implanted the two-stage revision arthroplasty using custom-made mobile articulating spacer made by used femoral stem coating with bone cement containing gentamycin and vancomycin with or without meropenem.After surgery,CN-PJI patients were treated with combination of IV antimicrobial antibiotics therapy for 6 weeks.All patients were followed at 1year and 3years after revision surgery.Results: A total of the 49 cases were reviewed.Based on the culture result,33 patients were divided into CP-PJI group and 16 patients were divided into CN-PJI group.CN-PJIs were associated with older age,smoking,diabetes and pre-operative antibiotic treatment,and pre-operative antibiotics are the most significant risk factors.The CN-PJI group showed a significantly higher incidence of prior antibiotic use(p=0.0067)and lower serum C-reactive protein(CRP)and ESR level(p < 0.001)than the CP-PJI group.Normalized time interval of CRP level in CN-PJI was shorter than that of CP-PJI group.The mean interval time for two-stage exchange arthroplasty was also significantly lower(p=0.049)in the CN-PJI group than the CP-PJI group.In CN-PJI group the prosthetic median survival time 43 months(2-108 months),which has a significant longer survival span than CP group(prosthetic median survival time12 months,15d-48 months).33 patients have found definite pathogenic bacterium and the most common pathogens of PJI are Staphylococcus aureus and coagulase-negative staphylococci(60.6%).There was no case of treatmentfailure or major complication in CN-PJI group.The rate of re-infection in the CN-PJI group showed a significantly difference between the CP-PJI group.Conclusion: The results of present study demonstrated that there were no significant differences in clinical characteristics between culture negative and culture-positive groups at medium term follow-up other than higher incidence of previous antibiotic and surgical treatment in the culture-negative group.Two-stage revision had a high success rate for eradication of periprosthetic hip joint infection,.Furthermore,treatment success rate was higher in the culture negative group than that of the culture-positive group,suggesting that culture negativity may not necessarily be a negative prognostic factor for periprosthetic joint infection.