Increasing Resistance of Coagulase-Negative Staphylococci in Total Hip Arthroplasty Infections: 278 THA-Revisions due to Infection Reported to the Norwegian Arthroplasty Register from 1993 to 2007

Abstract

We investigated bacterial findings from intraoperative tissue samples taken during revision due to infection after total hip arthroplasty (THA). The aim was to investigate whether the susceptibility patterns changed during the period from 1993 through 2007. Reported revisions due to infection in the Norwegian Arthroplasty Register (NAR) were identified, and 10 representative hospitals in Norway were visited. All relevant information on patients reported to the NAR for a revision due to infection, including bacteriological findings, was collected from the medical records. A total of 278 revision surgeries with bacterial growth in more than 2 samples were identified and included. Differences between three 5-year time periods were tested by the chi-square test for linear trend. The most frequent isolates were coagulase-negative staphylococci (CoNS) (41%, 113/278) and Staphylococcus aureus (19%, 53/278). The proportion of CoNS resistant to the methicillin-group increased from 57% (16/28) in the first period, 1993–1997, to 84% (52/62) in the last period, 2003–2007 (P = 0.003). There was also significant increase in resistance for CoNS to cotrimoxazole, quinolones, clindamycin, and macrolides. All S. aureus isolates were sensitive to both the methicillin-group and the aminoglycosides. For the other bacteria identified no changes in susceptibility patterns were found.

One-year incidence of prosthetic joint infection in total hip arthroplasty: a cohort study with linkage of the Danish Hip Arthroplasty Register and Danish Microbiology Databases

“…This correlates with previous reports from Denmark, which found that the incidence of MRSA in Denmark remains low despite an increase in recent years 42 (approximately 1.7% of tested S. aureus being MRSA in Denmark compared with 18% in Europe as a whole 43 ). Other studies of bacteria identified from arthroplasty revisions in Scandinavia have found a similarly low prevalence of MRSA 6,7,39 . The discrepancy between the relative risk of PJI incidence estimated by DHR data separately and the relative risk estimated by microbiology separately was surprising.…”

“…A suggested explanation for the increasing incidence of PJI reported from the 1990's to the beginning of the twenty first century is an increase in antimicrobial resistance 5 . Several studies, without linkage with arthroplasty registers, have identified an increase in beta-lactam-resistant CoNS during this period 6,7 . We did not detect a change in antimicrobial resistance in our study e despite a similar study design and size.…”

“…Other studies of Table II The five most common micro-organisms in the two study periods. More than one type of micro-organisssm was identified in 48 (19%) bacteria identified from arthroplasty revisions performed in Scandinavia have reported similar proportions of beta-lactam-resistant CoNS from 71% to 84% in the late 1990s and beginning of the twenty first century 6,7 . A possible explanation of this high prevalence of beta-lactam-resistant CoNS is that beta-lactam susceptible CoNS are eliminated by the preoperative prophylactic antibiotics.…”

“…A possible explanation of this high prevalence of beta-lactam-resistant CoNS is that beta-lactam susceptible CoNS are eliminated by the preoperative prophylactic antibiotics. Furthermore, previous studies have indicated that CoNS transform from susceptible to resistant strains following admission to hospital and selected by preoperative prophylaxis prior to primary THA surgery 6,39,40 . Currently, the most common used preoperative prophylaxis antibiotic prior to revision surgery is cefuroxime and dicloxacillin 41 , but the high prevalence of beta-lactam-resistant CoNS in the later study period might result in an increased risk of incomplete antibiotic coverage and infection clearance.…”

Antimicrobial susceptibility and body site distribution of community isolates of coagulase‐negative staphylococci

“…Among hospital CoNS isolates, the resistance pattern is markedly different (8,10,25). A Norwegian study on antimicrobial resistance patterns of clinical CoNS isolates from total hip arthroplasty infections during 1993-2007 reported an increase in methicillin resistance rates from 57 to 84%, as well as increasing rates of resistance to most other antimicrobials tested (26). Antimicrobial resistance is, however, not routinely monitored in commensal CoNS and we do not know if the prevalence of resistance in the community has increased.…”