Outcome of patients over 80 years of age on prolonged suppressive antibiotic therapy for at least 6 months for prosthetic joint infection.

OBJECTIVES To describe elderly patients treated with prolonged suppressive antibiotic therapy for a prosthetic joint infection (PJI) in cases where the infected prosthesis could not be removed. METHODS All patients aged ≥80 years with a documented PJI and treated with prolonged suppressive antibiotic therapy for more than 6 months were included retrospectively in this study. The following events were noted: failure including persisting infection, relapse, new infection, treatment discontinuation due to severe adverse events, and related death, and also unrelated death. RESULTS Thirty-eight patients with a median age of 84 years (80-95 years) were included; there were 24 hip infections, 13 knee infections, and one shoulder infection. The main causative organisms were Staphylococcus aureus (39%) and Streptococcus agalactiae (16%). The most commonly prescribed antibiotics as prolonged suppressive therapy were penicillins. The median follow-up duration was 24 months; 60% of the patients were event-free at 24 months and were still on prolonged suppressive antibiotic therapy. Fifteen events (six failures and nine unrelated deaths) were observed. Hypoalbuminaemia, the presence of a sinus tract, and a staphylococcal PJI were associated with an increased risk of an event. CONCLUSIONS Prolonged suppressive antibiotic therapy is an alternative therapy in elderly patients with PJI when surgery is contraindicated and when the bacteria are susceptible to well-tolerated oral antimicrobial therapy such as beta-lactams.