The association between HIV infection and periprosthetic joint infection following total hip replacement in young adults
Keywords:total hip arthroplasty, HIV, AIDS, avascular necrosis, hip, periprosthetic joint infection
The HIV burden in South Africa is high. HIV-positive patients are at risk of developing avascular necrosis of the femoral head, necessitating total hip arthroplasty (THA) at a relatively young age. The primary aim of this study was to investigate the relationship between HIV infection and the risk of periprosthetic joint infection (PJI) in young adults following total hip replacement. Secondly, we aimed to evaluate the association of HIV infection with venous thromboembolic events, reoperation and revision surgery.
We undertook a retrospective cohort study involving patients under the age of 55 years who underwent THA between 2009 and 2016 at a tertiary level arthroplasty unit. In total, 290 cases in 213 patients were analysed, with 77 patients requiring bilateral THA. The median age of patients was 43 years (interquartile range [IQR] 39–48, range 26–54 years). Sixty-two per cent of patients were HIV positive (n=180) with a median CD4 count of 520 cells/mm³ (IQR 423–659, range 238–1308 cells/mm³). Seventy-eight per cent (n=141) of the HIV-positive patients were on antiretroviral medication before surgery. Almost all cases performed in the HIV-positive group were for avascular necrosis (n=178, 99%).
At a median follow-up of four years (range 2–10) there were no revisions in either group. The incidence of PJI was 1.1% in the HIV-positive group vs 0.9% in the HIV-negative group. The odds ratio for the development of PJI in HIV-positive patients was 1.22 (95% CI 0.11 to 13.67, p=0.869). There was no association between the CD4 count of HIV-positive patients and the development of PJI (p=0.171). There was no difference in the rate of venous thromboembolic events between the HIV-positive and HIV-negative groups (4% vs 6%, p=0.340).
We report on a cohort of young adult patients who underwent THA. Patients living with HIV infection were not found to be at increased risk for PJI following THA, when compared to HIV-negative patients. The premise that HIV infection increases the risk for PJI following THA remains to be substantiated. This study was underpowered in terms of the primary outcome measure and larger studies are required to verify these findings.
Level of evidence: Level 4