title: Improved diagnosis of infection associated with osteosynthesis by use of sonication of fracture fixation implants.
abstract: Previous studies have shown that sonication fluid cultures from removed orthopedic devices improved the microbiological diagnosis of orthopedic implant-associated infections; however, few of these investigations have applied sonication to the removed fracture fixation devices to evaluate its utility for the diagnosis of osteosynthesis-associated infection (OAI). We compared sonication fluid to conventional tissue cultures from 180 subjects with different sizes of plates and screws (n = 156), spinal implants (n = 26), and intramedullary nails (n = 3), of whom 125 and 55 subjects had OAI and noninfected osteosynthesis (NIO), respectively. The sensitivity for detecting OAI was 90.4% for sonication fluid culture and 56.8% for periprosthetic tissue cultures (P < 0.05), and the specificities were 90.9% and 96.4%, respectively. Sonication fluid culture detected more pathogens than peri-implant tissue culture (113 versus 71; P < 0.001), while polymicrobial infections were diagnosed by sonication fluid cultures and tissue cultures in 20.8% and 8% (P < 0.001), respectively. Microbiological diagnosis was achieved exclusively by sonication fluid cultures for 47 (90.4%) subjects, and among them, 18 (38.3%) had previously received antibiotics, whereas in five (9.6%) infected subjects, tissue culture was positive and the sonication fluid culture was negative. Among 39 (31.2%) OAI cases receiving antibiotics, the identification of the organisms occurred in 38.5% and 82.1% of the tissue and sonication fluid cultures, respectively (P < 0.049). We demonstrated that sonication fluid culture from removed osteosyntheses has the potential for improving the microbiological diagnosis of OAI.
authors.affiliation: Infection Control Unit, Santa Isabel Hospital, São Paulo, Brazil.
authors.forename: Maysa Harumi
authors.initials: MH
authors.lastname: Yano
authors.affiliation: Division of Infectious Diseases, Department of Internal Medicine, Santa Casa de São Paulo School of Medicine, São Paulo, Brazil.
authors.forename: Giselle Burlamaqui
authors.initials: GB
authors.lastname: Klautau
authors.affiliation: Department of Laboratory Medicine and Pathology, Santa Casa de São Paulo School of Medicine, São Paulo, Brazil.
authors.forename: Cely Barreto
authors.initials: CB
authors.lastname: da Silva
authors.affiliation: Department of Laboratory Medicine and Pathology, Santa Casa de São Paulo School of Medicine, São Paulo, Brazil.
authors.forename: Stanley
authors.initials: S
authors.lastname: Nigro
authors.affiliation: Department of Orthopedic Surgery, Santa Casa de São Paulo School of Medicine, São Paulo, Brazil.
authors.forename: Osmar
authors.initials: O
authors.lastname: Avanzi
authors.affiliation: Department of Orthopedic Surgery, Santa Casa de São Paulo School of Medicine, São Paulo, Brazil.
authors.forename: Marcelo Tomanink
authors.initials: MT
authors.lastname: Mercadante
authors.affiliation: Division of Infectious Diseases, Department of Internal Medicine, Santa Casa de São Paulo School of Medicine, São Paulo, Brazil mcsalles@osite.com.br.
authors.forename: Mauro Jose Costa
authors.initials: MJ
authors.lastname: Salles
mesh_terms: D000293:Adolescent; D000328:Adult; D002648:Child; D005260:Female; D005592:Fracture Fixation / Q000009:adverse effects*; D006801:Humans; D008297:Male; D008828:Microbiological Techniques / Q000379:methods*; D008875:Middle Aged; D016459:Prosthesis-Related Infections / Q000175:diagnosis*; D012680:Sensitivity and Specificity; D013010:Sonication / Q000379:methods*; D055815:Young Adult