The relationship between microbiology results in the second of a two-stage exchange procedure using cement spacers and the outcome after revision total joint replacement for infection: the use of sonication to aid bacteriological analysis.
Patients with infected arthroplasties are normally treated with a two-stage exchange procedure using polymethylmethacrylate bone cement spacers impregnated with antibiotics. However, spacers may act as a foreign body to which micro-organisms may adhere and grow. In this study it was hypothesised that subclinical infection may be diagnosed with sonication of the surface biofilm of the spacer. The aims were to assess the presence of subclinical infection through sonication of the spacer at the time of a second-stage procedure, and to determine the relationship between subclinical infection and the clinical outcome. Of 55 patients studied, 11 (20%) were diagnosed with subclinical infection. At a mean follow-up of 12 months (interquartile range 6 to 18), clinical failure was found in 18 (32.7%) patients. Of the patients previously diagnosed with subclinical infection, 63% (7 of 11) had failed compared with 25% (11 of 44) of those without subclinical infection (odds ratio 5.25, 95% confidence interval 1.29 to 21.4, p = 0.021). Sonication of the biofilm of the surface of the spacer is useful in order to exclude subclinical infection and therefore contributes to improving the outcome after two-stage procedures.
Parc de Salut Mar, Service of Internal Medicine and Infectious Diseases, Passeig Marítim 25-29, Passeig Marítim 25-29, E-08003 Barcelona, Spain. 94021@parcdesalutmar.cat
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L
Sorlí
L
L
Puig
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R
Torres-Claramunt
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A
González
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A
Alier
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Knobel
M
M
Salvadó
J P
JP
Horcajada
D000328:Adult; D000368:Aged; D000369:Aged, 80 and over; D000900:Anti-Bacterial Agents / Q000008:administration & dosage; D019072:Antibiotic Prophylaxis / Q000379:methods; D019643:Arthroplasty, Replacement / Q000379:methods*; D018441:Biofilms; D001843:Bone Cements; D004343:Drug Implants; D005260:Female; D006090:Gram-Negative Bacteria / Q000302:isolation & purification / Q000502:physiology; D016905:Gram-Negative Bacterial Infections / Q000175:diagnosis; D006094:Gram-Positive Bacteria / Q000302:isolation & purification / Q000502:physiology; D016908:Gram-Positive Bacterial Infections / Q000175:diagnosis; D006801:Humans; D007595:Joint Prosthesis / Q000009:adverse effects*; D008297:Male; D008875:Middle Aged; D019904:Polymethyl Methacrylate; D011446:Prospective Studies; D011475:Prosthesis Failure; D016459:Prosthesis-Related Infections / Q000175:diagnosis* / Q000188:drug therapy / Q000517:prevention & control; D013010:Sonication / Q000379:methods*; D016896:Treatment Outcome
D000900:Anti-Bacterial Agents; D001843:Bone Cements; D004343:Drug Implants; D019904:Polymethyl Methacrylate