CLASSIFICATION AND ALGORITHM FOR DIAGNOSIS AND TREATMENT OF HIP PROSTHETIC JOINT INFECTION

Abstract

Prosthetic joint infection (PJI) is the second common reason for revision surgery of the hip joint prosthesis. The rate of hip PJI is about 1% after primary surgery and it goes up to 4% or higher after revision surgery. In most cases, the main cause of this complication is an intraoperative bacterial contamination, rarer is a haematogenic one. An up-to-date diagnostic approach and clearly defined treatment strategy are required for the successful therapy of PJI. Based on the analysis of the scientific literature and own experience, an algorithm for diagnosis and treatment of this complication is proposed. A thoroughly obtained case history plays a predominant role in the diagnosis of PJI. Lack of the increased serum C-reactive protein cannot be considered as an exclusion criterion because in some cases, especially chronic infection, it can be within the normal range. Bacteriology lab tests of periprosthetic tissue biopsies and synovial fluid is the gold standard for the diagnosis. Novel methods such as ultrasound debridement of the removed prosthetic components have allowed to substantially increase the diagnostic sensitivity of bacteriology tests. This led to the discovery of PJI in some cases which before that were regarded as aseptic loosening. Visualization methods including MRI and scintigraphy play only a secondary role. The authors propose the classification of PJI for further determination of the treatment strategy which takes into account parameters such as biofilm maturity, prosthesis stability, the type of pathogen and soft tissue state for the decision on the treatment strategy. While desire to retain the implant is only justified in case of the immature biofilm, in most cases the infection can be cured only after the replacement of endoprosthesis. According to the proposed algorithm, patients undergo one- or two-stage procedure with a short or long interval. Antibiotics that are active against biofilm pathogens play an important role in the efficacy of the therapy. Selection of these antibiotics should be based on the results of bacteriology tests, preferably in collaboration with specialists in infectious diseases and microbiology.