Trauma mechanism and patient reported outcome in tibial plateau fractures with posterior involvement.

INTRODUCTION: Posterior tibial plateau fractures (PTPF) have a high impact on functional outcome and the optimal treatment strategy is not well established. The goal of this study was to assess the relationship between trauma mechanism, fracture morphology and functional outcome in a large multicenter cohort and define possible strategies to improve the outcome. METHODS: An international retrospective cohort study was conducted in five level-1 trauma centers. All consecutive operatively treated PTPF were evaluated. Preoperative imaging was reviewed to determine the trauma mechanism. Patient reported outcome was scored using the Knee injury and Osteoarthritis Outcome Score (KOOS). RESULTS: A total of 145 tibial plateau fractures with posterior involvement were selected with a median follow-up of 32.2 months (IQR 24.1-43.2). Nine patients (6%) sustained an isolated posterior fracture. Seventy-two patients (49%) sustained a two-column fracture and three-column fractures were diagnosed in 64 (44%) patients. Varus trauma was associated with poorer outcome on the 'symptoms' (p = 0.004) and 'pain' subscales (p = 0.039). Delayed-staged surgery was associated with worse outcome scores for all subscales except 'pain'. In total, 27 patients (18%) were treated with posterior plate osteosynthesis without any significant difference in outcome. CONCLUSIONS: Fracture morphology, varus trauma mechanism and delayed-staged surgery (i.e. extensive soft-tissue injury) were identified as important prognostic factors on postoperative outcome in PTPF. In order to assess possible improvement of outcome, future studies with routine preoperative MRI to assess associated ligamentous injury in tibial plateau fractures (especially for varus trauma) are needed.

Adherence to local hospital guidelines for surgical antimicrobial prophylaxis: a multicentre audit in Dutch hospitals.

OBJECTIVE: To study the adherence to local hospital guidelines for antimicrobial prophylaxis in surgery, and explore reasons for non-adherence. METHODS: A prospective, multicentre audit of elective procedures, without prior suspicion of infection, was carried out in 13 Dutch hospitals. By reviewing medical, anaesthetic and nursing records, and medication charts, the prescription of antibiotics was compared with the local hospital guideline on antibiotic choice, duration of prophylaxis, dose, dosing interval and timing of the first dose. RESULTS: Between January 2000 and January 2001, 1763 procedures were studied. Antibiotic choice, duration, dose, dosing interval and timing of the first dose were concordant with the hospital guideline in 92%, 82%, 89%, 43% and 50%, respectively. Overall adherence to all aspects of the guideline, however, was achieved in only 28%. The most important barriers to local guideline adherence were lack of awareness due to ineffective distribution of the most recent version of the guidelines, lack of agreement by surgeons with the local hospital guidelines, and environmental factors, such as organizational constraints in the surgical suite and in the ward. CONCLUSION: This study shows that, although adherence to separate aspects of local hospital guidelines for surgical prophylaxis in the Netherlands is favourable, overall adherence to all parameters is hard to achieve. Adherence to guidelines on dosing interval and timing needs improvement, in particular. To increase the quality of antimicrobial prophylaxis in surgery, effort should be put into developing guidelines acceptable to surgeons, in adequately distributing the guidelines and to facilitating logistics. Audits of surgical prophylaxis may help hospitals identify barriers to guideline adherence.

Exogenous re-infection as a cause of recurrent tuberculosis in a low-incidence area.

SETTING: Surveillance data from the National Tuberculosis Register for the period 1993-1997 complemented with DNA fingerprinting results of Mycobacterium tuberculosis isolates. OBJECTIVE: To estimate the proportion of disease attributable to recent re-infection among Dutch tuberculosis patients with reported tuberculosis infection or disease before 1981. DESIGN: Data from 1,547 Dutch patients diagnosed between 1994 and 1997 in the Netherlands were studied. Cases with reported tuberculosis infection or disease before 1981 were attributed to reactivation if their M. tuberculosis isolate was unclustered based on DNA fingerprinting or if they were the first case in a cluster, and to re-infection if they were clustered, but not as the first case. RESULTS: In total, 183 Dutch tuberculosis patients (12%) had reported tuberculosis infection or disease before 1981. Tuberculosis in 29 of these patients (16%) was attributed to recent re-infection. CONCLUSION: In this setting with a low tuberculosis incidence, approximately one in six new disease episodes among patients with previous tuberculosis infection or disease may be attributable to recent re-infection.

Surveillance of hospital-acquired infection in England, Germany, and The Netherlands: will international comparison of rates be possible?

Three national surveillance systems for nosocomial infection have been developed independently and implemented successfully in England, Germany, and The Netherlands. All three are based on the American National Nosocomial Infections Surveillance System and have adopted a surveillance strategy that is targeted at specific infections or groups of patients for limited time periods. Case-finding methods, the minimum data set, and analysis of data are similar and could be standardized easily. Resolution of the differences in the definitions of infection, the study population, and follow-up should make possible the international comparison of infection rates. Such comparisons may identify differences in healthcare practices between countries and suggest areas for improvement.

[Hospital infections and risk factors in the intensive care units of 16 Dutch hospitals, results of surveillance of quality assurance indicators]. / Ziekenhuisinfecties en risicofactoren op de intensive-careafdelingen van 16 Nederlandse ziekenhuizen; resultaten van surveillance als indicator voor zorgkwaliteit.

OBJECTIVE: To gain insight into the incidence of nosocomial infections and associated risk factors in Intensive Care Units (ICUs). DESIGN: Prospective. METHOD: From July 1997 to December 1999, standardised surveillance of nosocomial infections was implemented in ICUs in 16 hospitals in the Netherlands. Surveillance was performed in patients with an ICU stay of > or = 48 hrs; data were collected from admission until discharge from ICU. Data-collection included demographic data and patient- and treatment-related risk factors. The data were aggregated in a national database. RESULTS: In the research period, hospitals sent good quality data for aggregation in the national database on 2795 patients (61% male) and 27,922 ICU patient days. The median length of stay was six days, the median 'Acute physiology and chronic health evaluation' (APACHE) II score was 17 and the median age was 67 years. A total number of 749 infected patients were found with 1,177 nosocomial infections (27% of patients, 42 infections/1000 patient days), consisting of 43% pneumonia, 20% sepsis, 21% urinary tract infections, 16% other types of infections. Out of all the patients, 62% was on mechanical ventilation, 64% had a central venous line and 89% had a urinary catheter in situ. Selective decontamination of the gastrointestinal tract was used for 12% of the patients, and systemic antibiotics for 68%. Micro-organisms most frequently isolated were Pseudomonas aeruginosa in patients with pneumonia, Staphylococcus epidermidis in catheter-related bloodstream infections and Escherichia coli in patients with urinary tract infections. Large differences in device use and incidence of infections were observed between the ICUs. CONCLUSION: The aggregated data gave insight into the incidence of nosocomial infections and associated risk factors in ICUs. The data are meant as references to support decision- and policy-making in local infection control programs.

Risk assessment for surgical site infections following total hip and total knee prostheses.

The purpose of the study was to assess the relative importance of risk factors for surgical site infections (SSI) following total hip and total knee prostheses in The Netherlands. In the period 1996-99 63 hospitals in The Netherlands registered SSI after 36,629 orthopedic operations. Total hip and total knee prostheses were analyzed in detail. The results of our study showed that a long preoperative stay was a risk factor for deep SSIs after both procedures. A dirty or contaminated wound and a serious systemic condition were risk factors for deep SSIs after total hip prostheses. If post-discharge surveillance was carried out, more SSIs were found, for total knee prostheses more than twice as many. Independent risk factors for SSIs after total hip prostheses were a contaminated/dirty wound and for total knee prostheses a short operation duration. The authors conclude that surveillance of surgical site infections following total hip and total knee prostheses revealed different risk factors for (deep) SSIs.

Genetic heterogeneity in Mycobacterium tuberculosis isolates reflected in IS6110 restriction fragment length polymorphism patterns as low-intensity bands.

Mycobacterium tuberculosis isolates with identical IS6110 restriction fragment length polymorphism (RFLP) patterns are considered to originate from the same ancestral strain and thus to reflect ongoing transmission. In this study, we investigated 1,277 IS6110 RFLP patterns for the presence of multiple low-intensity bands (LIBs), which may indicate infections with multiple M. tuberculosis strains. We did not find any multiple LIBs, suggesting that multiple infections are rare in the Netherlands. However, we did observe a few LIBs in 94 patterns (7.4%) and examined the nature of this phenomenon. With single-colony cultures it was found that LIBs mostly represent mixed bacterial populations with slightly different RFLP patterns. Mixtures were expressed in RFLP patterns as LIBs when 10 to 30% of the DNA analyzed originated from a bacterial population with another RFLP pattern. Presumably, a part of the LIBs did not represent mixed bacterial populations, as in some clusters all strains exhibited LIBs in their RFLP patterns. The occurrence of LIBs was associated with increased age in patients. This may reflect either a gradual change of the bacterial population in the human body over time or IS6110-mediated genetic adaptation of M. tuberculosis to changes in the environmental conditions during the dormant state or reactivation thereafter.

Emerging group-A rotavirus and a nosocomial outbreak of diarrhoea.

A P[6]G9 group-A rotavirus caused a protracted hospital outbreak of neonatal diarrhoea in The Netherlands. The outbreak lasted 5 months with 52 cases and an average attack rate of 40%, 46 cases were in an incubator section for neonates under 1 month of age. Rotavirus P161G9 was detected by RT-PCR in stool samples from the 31 cases tested. Emergence of this genotype in Europe may have implications for neonates lacking protective maternal antibodies and for the development of rotavirus vaccines.

An operating surveillance system of surgical-site infections in The Netherlands: results of the PREZIES national surveillance network. Preventie van Ziekenhuisinfecties door Surveillance.

OBJECTIVES: To describe the results of the first year of the Dutch national surveillance of surgical-site infections (SSIs) and risk factors, which aims to implement a standardized surveillance system in a network of Dutch hospitals, to collect comparable data on SSIs to serve as a reference, and to provide a basic infrastructure for further intervention research. DESIGN: Prospective multicenter cohort study. SETTING: Acute-care hospitals in The Netherlands from June 1996 to May 1997. RESULTS: 38 hospitals participated, with a slight over-representation of larger hospitals. Following a total of 18,063 operations, 562 SSIs occurred, of which 198 were deep. Multivariate analysis of pooled procedures shows that age, preoperative length of stay, wound contamination class, anesthesia score, and duration of surgery were independent risk factors for SSI. When analyzed by procedure, the relative importance of these risk factors changed. Bacteriological documentation was available for 56% of the SSIs; 35% of all isolates were Staphylococcus aureus. Multiple regression analysis computed the mean extra postoperative length of stay associated with SSI to be 8.2 days. CONCLUSION: The first year of national surveillance has shown that it is feasible to collect comparable data on SSI, which are already used for education, policy, and decision making in the network of participating hospitals. This gives room to effectuate the next aim, namely to use the network as an infrastructure for intervention research. Multivariate analysis shows that feedback on a procedure-specific level is important.

Interpreting DNA fingerprint clusters of Mycobacterium tuberculosis. European Concerted Action on Molecular Epidemiology and Control of Tuberculosis.

Many studies of tuberculosis have defined clusters of patients on the basis of shared DNA fingerprint patterns of their Mycobacterium tuberculosis isolates. Clustering has been equated with recent transmission, and factors associated with clustering have been sought as a guide to population subgroups with high rates of ongoing transmission of M. tuberculosis. Considerable caution should be exercised in conducting and interpreting these studies. Groups of strains may be identical for reasons other than recent transmission, depending, for example, on the stability of the marker and the number of strains in the population over time. Cases actually due to recent transmission may not be seen as clustered if they are new immigrants to the population or if not all cases in the population are included in the study. The amount of clustering seen will depend on the duration of the study. Studies should give precise information on the study setting, the proportion of cases included, the recruitment period and the definition of clustering used. The data on clustering should be disaggregated at least by age, sex and immigration status. To be maximally informative, studies should involve a high proportion of all cases in a population, be conducted in conjunction with conventional epidemiological investigations of contacts (if possible), and should provide information on tuberculosis incidence in the population and on patients' age, sex, human immunodeficiency virus status, drug resistance and social and ethnic group.

Analysis of rate of change of IS6110 RFLP patterns of Mycobacterium tuberculosis based on serial patient isolates.

The rate of change of IS6110 restriction fragment length polymorphism (RFLP) patterns of Mycobacterium tuberculosis was determined in serial isolates from 544 patients. In 25 patients (4.6%), the RFLP patterns of the follow-up isolates differed from the initial isolates. Patients with different follow-up strains were less likely to cluster with patients whose strains had indistinguishable RFLP patterns. Changes in RFLP patterns were more common for persons with extrapulmonary disease and for those who had both pulmonary and extrapulmonary isolates. Based on serial isolates spanning for the most part <3 months, the half-life was extrapolated to be 3.2 years (95% confidence interval, 2.1-5.0). The main implication of this study is that the rate of change of IS6110-based RFLP of M. tuberculosis supports the use of IS6110 typing in epidemiologic studies of recent transmission of tuberculosis.

Risk assessment for surgical-site infections in orthopedic patients.

OBJECTIVE: To assess the relative importance of risk factors for surgical-site infections (SSIs) in orthopedic patients and thereby determine which risk factors to monitor in the national surveillance of SSI in The Netherlands. DESIGN: Reanalysis of data on SSI and associated risk factors from two surveillance projects on nosocomial infections, carried out in 1992 and 1993 in The Netherlands: Project Surveillance Nosocomial Infections in the region of Utrecht (PSZU) and the first Project Surveillance Surgical Wound Infections (SWIFT-1). Odds ratios (ORs) were calculated for age, gender, preoperative stay, and the number of operations. In addition, in PSZU, other nosocomial infections, and, in SWIFT-1, prophylactic antibiotics, acute surgery, and wound contamination were studied. PARTICIPANTS: The study was confined to hospitalized orthopedic patients (PSZU, 4,872; SWIFT-1, 6,437). RESULTS: In PSZU, the following ORs were significant in a multivariate model: age 0-44 years, 1.0; 45-64 years, 1.6; 65-74 years, 4.7; and 75-99 years, 6.0. For a preoperative stay over 4 days, the OR was 3.3 (95% confidence interval [CI95], 2.5-4.0), and for multiple surgery, 2.5 (CI95, 1.9-3.0). For females, the OR was 0.8 (not significant). The same model applied to SWIFT-1 gave similar ORs. Adjustment for additional nosocomial infections (PSZU) decreased the ORs for ages over 65 years remarkably. The OR for additional nosocomial infections in patients under 65 years of age was 15.6 (CI95, 4.3-57.4). Adjustment for prophylactic antibiotics, acute surgery, and wound-contamination class (SWIFT-1) did not influence the ORs of the original model, but showed that wound-contamination class was an important risk factor. CONCLUSIONS: Age, additional nosocomial infections, wound-contamination class, preoperative stay, and the number of operations were identified as important risk factors for SSI in Dutch orthopedic patients.

[Secondary infection with methacillin resistant Staphylococcus aureus in Dutch hospitals (July 1997-June 1996]. / Secundaire besmetting met meticillineresistente Staphylococcus aureus in Nederlandse ziekenhuizen (juli 1994-juni 1996).

OBJECTIVE: To study the spread of methicillin-resistant Staphylococcus aureus (MRSA) in hospitals, especially secondary MRSA infections in relation to the origin of the MRSA strain and the measures taken regarding contact isolation. DESIGN: Secondary data analysis. METHODS: As part of the national MRSA surveillance of the National Institute of Public Health and the Environment, data were collected using questionnaires. The analysis covered the period July 1994-June 1996 and was performed for index cases of secondary infections versus sporadic cases. Possible risk factors were determined. RESULTS: In the study period 30 index cases of (clusters of) secondary infections and 191 sporadic cases were found. The size of the clusters was limited. Strict contact isolation as described in the guidelines of the Dutch Working Group on Infection Prevention prevented secondary infections in most cases. Patients for whom no relation could be found between the MRSA infection and a stay abroad were found to have caused more secondary infections, even when the data were corrected for contact isolation measures.

[Incidence of postoperative wound infections in The Netherlands]. / Frequentie van postoperatieve wondinfecties in Nederland.

OBJECTIVE: To inventory postoperative infections in Dutch hospitals. DESIGN: Descriptive study. SETTING: National organization for quality assurance in hospitals, Utrecht, the Netherlands. METHOD: In 36 Dutch hospitals data on surgical patients, surgical site infections and risk factors were collected, using standardised methods, as part of a quality system by which hospitals could compare their infection rates with the rates in the database. RESULTS: Surveillance of surgical site infections was introduced in 36/118 (31%) hospitals. Data on 32,869 surgical procedures were collected, 1115 (3.4%) surgical site infections were found. The infection rates by wound contamination class varied from 2.2% (95% confidence interval (CI): 2.0-2.4) in clean wounds to 11% (95% CI: 9.3-12.8) in dirty wounds; the infection rates by duration of operation varied from 3% (95% CI: 2.8-3.2) in operations lasting less than two hours to 10.8% (95% CI: 6.0-18.5) in operations lasting more than 8 hours; the infection rate by ASA classification varied from 2.7% (95% CI: 2.3-3.2) in class I to 15.5% (95% CI: 8.4-26.5) in patients in class IV. Advanced age, emergency, preoperative stay were recognised as risk factors. The infection rates in the most frequently recorded types of operation varied from 0.2% (95% CI: 0.0-1.1) in varicose veins to 9.8% (95% CI: 7.2-13.2) in femoral bypass grafts. The use of antimicrobial prophylaxis varied per type of operation. The micro-organisms most frequently isolated were Staphylococcus aureus. Staphylococcus epidermidis, Pseudomonas aeruginosa, and Escherichia coli. Of the infections 32% were identified in the first week following surgery. Of the infected patients 88% stayed in hospital during one or more days following the onset of infection.

An outbreak of cryptosporidiosis in the Netherlands.

A hospital microbiologist in Spijkenisse, in the south west of the Netherlands - who had recently attended a parasitology course - identified cryptosporidial oocysts in stools from a patient with diarrhoea on 16 August 1995. Re-examination of 89 stool spe

Nutritional aspects of changes in disease patterns in the Western Pacific region.

One impact of socioeconomic progress on populations has been to reduce the number of cases due to diseases of undernutrition and microbial contamination of food, which affected mostly infants and young children, and to increase those due to diseases of excessive food consumption, which are affecting adults and a growing number of children. This article reviews the main dietary factors which have an influence on cardiovascular disease and cancer, and discusses the link between economic development and increased rates of chronic diseases. There is evidence that the noncommunicable diseases and their risk factors have risen rapidly in countries of the WHO Western Pacific Region. Data from 29 countries and areas in the region indicate that 70% of them show lifestyle diseases in three or more of the top five causes of death. While public health measures have been implemented by some countries to prevent and control nutrition-related chronic diseases, further action is needed.