Treatment of infectious nonspecific coxitis in HIV-positive patients using an antibiotic-loaded spacer for the hip joint

Introduction The fight with nonspecific infection in immunodeficient HIV-infected patients is challenging. There are no standardized treatment protocols yet. The most effective treatment method of purulent coxitis remains two-stage total hip arthroplasty with the first stage of joint resection and implantation of an antibiotic‑loaded cement spacer, and the second stage of total hip replacement. One of the ways to reduce poor results and revision interventions is the development of new types of spacers for treatment of coxitis in patients with HIV infection. The aim of the work is to demonstrate the effectiveness of a new method of surgical treatment of infectious coxitis in HIV-infected patients using an original design of an antibiotic-loaded articulating spacer in two clinical cases. Materials and methods The treatment results of two HIV-positive patients with infectious coxitis, in whom an original two-layer design of an antibiotic-loaded cement spacer based on the individual bacterial sensitivity was applied at the first stage of treatment, were retrospectively evaluated. To study the effectiveness of this method we used the results of the dynamics of pain evaluation according to Visual Analogue Scale (VAS), the functional state of the affected joint using Harris Hip Score (HSS), Western Ontario and McMaster University osteoarthritis Index (WOMAC) scale and radiological data of patients in the early postoperative period and after 12-month follow-up. Results Clinical cases demonstrate positive results of treatment of infectious coxitis associated with HIV infection. Application of the developed spacer design allowed eradication of bacterial infection. As a result of using of the new spacer model with an antimicrobial effect in the first clinical case it was possible to restore the joint function from 35 to 89 HHS points, from 79 to 14 WOMAC points, to reduce the pain syndrome from 7 to 1 VAS point; in the second patient from 32 to 91 HHS points, from 84 to 11 WOMAC points, to reduce the pain syndrome from 6 to 0 VAS points. Discussion Based on scientific reports and our own clinical cases, we hypothesize that in HIV-associated purulent coxitis, one of the main reasons for poor results after two-stage arthroplasty is insufficient local concentration of antimicrobial agents, caused by the imperfect design of traditional cemented spacers. The original spacer design allows for a higher concentration and may become an effective alternative to traditional treatment methods. Conclusion Application of the developed technology of surgical treatment of infectious coxitis in HIV‑positive patients resulted in eradication of infection, reduction of pain syndrome, restoration of the hip joint functionality.