Modern techniques have reduced the frequency of infections that are associated with prosthetic joints, but such infections continue to pose difficult problems in clinical management. Advances in understanding biofilms and the pathogenesis of microbial interactions with the implant have led to more rational approaches to therapy. This review offers guidance in establishing the diagnosis correctly and an algorithm summarizing the appropriate medical and surgical options.

A 57-year-old man presents 2 weeks after prostate biopsy with fever, chills, and new lumbar back pain. His temperature is 39.7°C; he has an enlarged, tender prostate and lumbar spine tenderness. His white-cell count is 9100 per cubic millimeter, and the C-reactive protein level is 343 mg per liter. Urine and blood cultures reveal multidrug-resistant extended-spectrum β-lactamase–producing Escherichia coli susceptible to imipenem. How should he be evaluated and treated?

Implant-associated infection is caused by surface-adhering bacteria persisting as biofilm. Periprosthetic joint infection is difficult to diagnose an

Few studies have compared the long-term success of different surgical strategies in prosthetic knee-associated infection. Accordingly, a retrospective cohort study was performed of 40 episodes in 35 consecutive patients undergoing revision surgery for prosthetic knee-associated infection at a single centre between 1988 and 2003. The median patient age was 70 (44-90) years; the median follow-up period was 28 (2-193) months; 45% of infections were early, 23% were delayed, and 32% were late; and 55% of infections were caused by staphylococci. The probability of survival without prosthesis failure was 92.4% (95% CI, 84.1-100) after 1 year, and 88.7% (95% CI, 78-99.4) after 2 years. Recurrence-free survival was observed in 20 (95%) of 21 patients treated with debridement and retention, in both patients with one-stage exchange, and in 11 (85%) of 13 patients with two-stage exchange. Patients with delayed infection had a worse outcome than those with early or late infection (67% vs. 97%; p < 0.03). Patients with at least partially adequate antimicrobial therapy had a higher success rate than those with inadequate treatment (94% vs. 60%; p 0.069). The outcome was similar for patients with a duration of therapy of 3 to < 6 months, and those with a duration of therapy of > or = 6 months (91% vs. 87% success). Different surgical procedures had similar success rates, provided that the type of infection, the pathogen, the stability of the implant and the local skin and soft-tissue condition were considered. Adherence to an algorithm defining a rational surgical and antibiotic treatment strategy contributed to a favourable outcome.