Diagnose und Therapie von Gelenkprotheseninfektionen

Zusammenfassung: Mittels Gelenkprothese kann bei Patienten mit arthrotisch oder arthritisch destruierten Gelenken (Hüfte, Knie, Schulter und Ellenbogen) Schmerzfreiheit erreicht und gleichzeitig die Mobilität gesteigert werden. Die Gelenkprotheseninfektion gilt als schwerwiegende, implantatassoziierte Komplikation, welche mit erhöhter Morbidität und Gesundheitskosten einhergeht. Pathogenetisch handelt es sich bei der Gelenkprotheseninfektion um eine Fremdkörperinfektion mit Ausbildung eines Biofilms, was die Diagnose und Therapie erschwert. Low-grade-Infektionen einer Gelenkprothese manifestieren sich häufig in Form einer frühen Prothesenlockerung mit oder ohne persistierende Schmerzen. Klinisch ist somit ein Low-grade-Infekt kaum von einem aseptischen Prothesenversagen zu unterscheiden. Die definitive Diagnose einer Gelenkprotheseninfektion kann meistens erst durch die Kombination verschiedener prä- und intraoperativer Untersuchungen gestellt werden. Durch rheumatologische Grundkrankheiten kann das periprothetische Gewebe entzündlich verändert sein, sodass nur der kulturelle Nachweis des Mikroorganismus eine definitive Diagnose erlaubt. Der Therapieerfolg ist einerseits von einer adäquaten chirurgischen Intervention und andererseits von einer antibiotischen Langzeittherapie abhängig. Letztere sollte eine biofilmaktive Substanz enthalten. In diesem Artikel werden Pathogenese, Epidemiologie, Diagnostik und Therapie einer Gelenkprotheseninfektion diskutiert. Dabei wird der Schwerpunkt auf die diagnostische Abklärung gelegt, zumal diese bei rheumatologischer Grundkrankheit erschwert sein kan

Quality of life as subjective experience: Reframing of perception in patients with colon cancer undergoing radical resection with or without adjuvant chemotherapy

Purpose and background: We examined whether patients with colon cancer undergoing surgery with or without adjuvant chemotherapy change the internal standards on which they base their quality-of-life (QL) estimation, and, if they do so, whether this reframing alters interpretation of QL findings. These questions were addressed within a randomized clinical trial of the Swiss Group for Clinical Cancer Research (SAKK 40/93). Patients and methods: After radical resection of adenocar-cinoma of the colon (pT1-4pN>0M0 and pT3-4pN0M0) and perioperative chemotherapy, patients were randomized to three treatment arms: observation only (A), 5-FU 450 rag/m2plus Levamisol (B), or 5-FU 600 mg/m2 (C). QL was measured by linear analogue self-assessment indicators. Patients estimated their pre-surgery QL both before surgery and retrospectively thereafter, and their pre-adjuvant QL both at the beginning of randomly assigned chemotherapy or observation and retrospectively about two months later. Thereafter, current QL was assessed. Paired t-tests were used to test the hypotheses of no change. Results: Overall, 187 patients with at least one pair of corresponding questionnaires were analyzed. Patients estimated their pre-surgery QL after surgery significantly lower than before and their pre-adjuvant QL under treatment or observation also lower than at the beginning. In the adjuvant phase, in contradiction to our hypothesis, chemotherapy had almost no impact on these changes attributed to reframing. Conventionally assessed changes indicated an improvement in QL. Patients with treatment C reported less improvement in functional performance than those with B or those under observation (P = 0.04). Patients with treatment B indicated a greater worsening in nausea/vomiting than those with C, whereas patients with observation only showed an improvement (P = 0.0009). After adjustment of current QL scores under treatment or observation to patients' retrospective estimation, the treatment effects were diluted but the overall improvement was substantially amplified in most QL indicators. Conclusions: Patients with colon cancer substantially re-frame their perception in estimating QL both under radical resection and under adjuvant chemotherapy or observation. This effect is an integral part of patients' adaptation to disease and treatment. An understanding of this phenomenon is of particular relevance for patient care. Its role in evaluating QL endpoints in clinical trials needs further investigatio

Infrequent mutation of the tumour-suppressor gene Smad4 in early-stage colorectal cancer

Smad4 is a candidate tumour-suppressor gene identified recently on chromosome 18q21.1. Both alleles are inactivated in nearly one-half of pancreatic carcinomas, but its role in the tumorigenesis of other tumours is still unknown. The aim of this study was to investigate the potential involvement of the Smad4 locus in early-stage colorectal cancers (stages I–III) in tumour samples from a randomised multicentre trial. Of a large collection of DNA samples, 73 with a loss of one allele of the Smad4 gene were analysed for the presence of point mutations in the remaining gene. Patients, from whom biopsies were isolated, were part of a previous randomised multicentre study of the Swiss Group for Clinical Cancer Research on the benefit of adjuvant chemotherapy (SAKK study 40/81). Mutation analysis was restricted to the highly conserved C-terminal domain (exons 8, 9, 10 and 11) of Smad4, using PCR and single-strand conformational variant analysis. Two of the 73 patients (3%) with loss of one allele of Smad4 had a point mutation in the remaining allele. These results indicate that whereas Smad4 point mautations are prevalent in pancreatic carcinoma, they are infrequent in early stages (I–III) of colorectal cancer

One hundred and twelve infected arthroplasties treated with ‘DAIR’ (debridement, antibiotics and implant retention): antibiotic duration and outcome

OBJECTIVES: We describe treatment failure rates by antibiotic duration for prosthetic joint infection (PJI) managed with debridement, antibiotics and implant retention (DAIR). METHODS: We retrospectively collected data from all the cases of PJI that were managed with DAIR over a 5 year period. Surgical debridement, microbiological sampling, early intravenous antibiotics and prolonged oral follow-on antibiotics were used. RESULTS: One hundred and twelve cases of PJI were identified. Twenty infections (18%) recurred during a mean follow-up of 2.3 years. The mean duration of antibiotic use was 1.5 years. Failure was more common after arthroscopic debridement, for previously revised joints and for Staphylococcus aureus infection. There were 12 failures after stopping antibiotics and 8 while on antibiotics [hazard ratio (HR) = 4.3, 95% confidence interval (CI) 1.4-12.8, P = 0.01]. However, during the first 3 months of follow-up, there were eight failures after stopping antibiotics and two while on antibiotics (HR = 7.0, 95% CI 1.5-33, P = 0.015). The duration of antibiotic therapy prior to stopping did not predict outcome. CONCLUSIONS: PJI may be managed by DAIR. The risk of failure with this strategy rises after stopping oral antibiotics, but lengthening antibiotic therapy may simply postpone, rather than prevent, failure

Outsourcing and structural change: shifting firm and sectoral boundaries

The paper aims at investigating the structural change implications of outsourcing. In trying to bridge the organizational/industrial and the sectoral/structural analysis of outsourcing, it discusses the rational and the methodological pros and cons of a “battery” of outsourcing measurements for structural change analysis. Their functioning is then illustrated through a concise application of them to the OECD area over the ’80s and the early ’90s. A combined used of them emerges as recommendable in checking for the role of outsourcing with respect to that of other structural change determinants

Re-Infection Outcomes following One- and Two-Stage Surgical Revision of Infected Hip Prosthesis:A Systematic Review and Meta-Analysis

The two-stage revision strategy has been claimed as being the "gold standard" for treating prosthetic joint infection. The one-stage revision strategy remains an attractive alternative option; however, its effectiveness in comparison to the two-stage strategy remains uncertain.To compare the effectiveness of one- and two-stage revision strategies in treating prosthetic hip infection, using re-infection as an outcome.Systematic review and meta-analysis.MEDLINE, EMBASE, Web of Science, Cochrane Library, manual search of bibliographies to March 2015, and email contact with investigators.Cohort studies (prospective or retrospective) conducted in generally unselected patients with prosthetic hip infection treated exclusively by one- or two-stage revision and with re-infection outcomes reported within two years of revision. No clinical trials were identified.Data were extracted by two independent investigators and a consensus was reached with involvement of a third. Rates of re-infection from 38 one-stage studies (2,536 participants) and 60 two-stage studies (3,288 participants) were aggregated using random-effect models after arcsine transformation, and were grouped by study and population level characteristics.In one-stage studies, the rate (95% confidence intervals) of re-infection was 8.2% (6.0-10.8). The corresponding re-infection rate after two-stage revision was 7.9% (6.2-9.7). Re-infection rates remained generally similar when grouped by several study and population level characteristics. There was no strong evidence of publication bias among contributing studies.Evidence from aggregate published data suggest similar re-infection rates after one- or two-stage revision among unselected patients. More detailed analyses under a broader range of circumstances and exploration of other sources of heterogeneity will require collaborative pooling of individual participant data.PROSPERO 2015: CRD42015016559

SMAD4 is a predictive marker for 5-fluorouracil-based chemotherapy in patients with colorectal cancer

The gene for the transducer of transforming growth factor-beta/bone morphogenetic protein signalling SMAD4, a potential suppressor of colorectal carcinogenesis, is located at the chromosomal region 18q21. In order to evaluate the clinical relevance of SMAD4 deletion, gene copy alterations were determined by copy dosage using real-time quantitative PCR in 202 colorectal tumour biopsies from a previous randomised study of adjuvant chemotherapy. Patients with normal SMAD4 diploidy turned out to have a three-fold higher benefit of 5-fluorouracil-based adjuvant chemotherapy with a border line significance (overall survival: 3.23, P=0.056; disease-free survival: 2.89, P=0.045). These data are consistent with the previous observation that patients whose cancer had retention of the 18q21 region had a significantly higher benefit from 5-fluorouracil-based therapy. Moreover, these results may provide a refinement at the gene level of the clinical relevance of 18q21 deletion, thereby suggesting SMAD4 as a predictive marker in colorectal cancer. This data also indicate that integrity of this component of the transforming growth factor-beta/bone morphogenetic protein signalling pathway may be a critical factor for benefit of chemotherapy in patients with colorectal cancer