Purpose of the study: Staphylococcus lugdunensis, described in Lyon in 1988 by Freney, appears to be a member of the cutaneous perineal flora. Since the first description, S. lugdunensis infections are regularly reported. The germ has been reported as the causal agent for endocarditis on valve prostheses with a very severe prognosis, requiring surgery in addition to medical management. We wanted to ascertain the prognosis of such infections on joint prostheses and to determine if it is different from that with other staphylococcal species.

Material and methods: Since 1991, seven S. lugdunensis infections on a joint prosthesis (three total hip prostheses and four total knee arthroplasties) were identified in our department. The Api Id 32 staph (BioMérieux SA) test battery was used for identification. All patients underwent surgical treatment and were given a prolonged antibiotic regimen. Simple joint cleaning was performed in three cases, one requiring a one-stage prosthesis replacement. There were four two-stage prosthesis replacements. The antibiotic regimen was always long (3–8 months) and was continued as a palliative treatment in two patients who underwent simple cleaning.

Results: One elderly woman with multiple co-morbid conditions died after prosthesis removal before the replacement procedure could be performed. There were no cases of recurrent infection at 16 months and 6 years for the four prosthesis replacements (one- and two-stage procedures). Arthroscopic cleaning without removal of the TKA was a failure in one patient who required prosthetic replacement later. Two simple cleanings in elderly patients were failures and required continuous palliative antibiotics.

Discussion: Staphylococcus lugdunensis is generally considered to be very susceptible to antibiotics in vitro. In our experience, search for minimum inhibitory concentrations and minimum bactericidal concentrations have shown cures with rapid shifts which must be taken into consideration when choosing an antibiotic. With surgical removal of the prosthesis and adapted antibiotics, the prognosis of these infections is not different from other staphylococcal infections of joint prostheses. We did however note two cases of secondary infections, probably related to hematogeneous spread, which developed from an unidentifiable point in time.

Conclusion: Staphylococcus lugdunensis is a coagulase-negative staphylococcus with poorly known virulence properties. In our very small series of joint prostheses infections, therapeutic failure occurred when the infected prosthesis was not removed.