Introduction of the lung allocation score in Germany.

The aim of this study was to assess performance of the new lung allocation system in Germany based on lung allocation score (LAS). Retrospective analysis of waitlist (WL) outflow, lung transplantation (LTx) activity and 3-month outcomes comparing 1-year pre- and post-LAS introduction on December 10, 2011 was performed. Following LAS introduction, WL registrations remained constant, while WL mortality fell by 23% (p = 0.04). Reductions in WL mortality occurred in patients with cystic fibrosis (CF; -52%), emphysema (chronic obstructive pulmonary disease [COPD]; -49%) and pulmonary hypertension (PH; -67%), but not idiopathic pulmonary fibrosis (IPF; +48%). LTx activity increased by 9% (p = 0.146). Compared to pre-LAS, more patients with IPF (32% vs. 29%) and CF (20% vs. 18%) underwent transplantation and comparatively fewer with COPD (30% vs. 39%). Median LAS among transplant recipients was highest in PH (53) and IPF (49) and lowest in COPD (34). Transplantation under invasive respiratory support increased to 13% (in CF 28%, +85%, p = 0.017). Three-month survival remained unchanged (pre: 96.1% and post: 94.9%, p = 0.94). Following LAS implementation in Germany, reductions in waiting list size and WL mortality were observed. Composition of transplant recipients changed, with fewer COPD and more IPF recipients. Transplantation under invasive respiratory support increased. Reductions in WL mortality were most pronounced among CF and PH patients.

Cost-effectiveness of hypothermic machine preservation versus static cold storage in renal transplantation.

Static cold storage (CS) is the most widely used organ preservation method for deceased donor kidney grafts but there is increasing evidence that hypothermic machine perfusion (MP) may result in better outcome after transplantation. We performed an economic evaluation of MP versus CS alongside a multicenter RCT investigating short- and long-term cost-effectiveness. Three hundred thirty-six consecutive kidney pairs were included, one of which was assigned to MP and one to CS. The economic evaluation combined the short-term results based on the empirical data from the study with a Markov model with a 10-year time horizon. Direct medical costs of hospital stay, dialysis treatment, and complications were included. Data regarding long-term survival, quality of life, and long-term costs were derived from literature. The short-term evaluation showed that MP reduced the risk of delayed graft function and graft failure at lower costs than CS. The Markov model revealed cost savings of $86,750 per life-year gained in favor of MP. The corresponding incremental cost-utility ratio was minus $496,223 per quality-adjusted life-year (QALY) gained. We conclude that life-years and QALYs can be gained while reducing costs at the same time, when kidneys are preserved by MP instead of CS.

The influence of laboratory-induced MELD score differences on liver allocation: more reality than myth.

BACKGROUND: Liver allocation in Eurotransplant (ET) is based on the MELD score. Interlaboratory MELD score differences in INR and creatinine determination have been reported. The clinical implication of this observation has not been demonstrated. METHODS: MELD scores were calculated in 66 patients with liver cirrhosis using bilirubin, creatinine, and INR analyzed in six liver transplant centers. Based on allocation results of ET, patients transplanted from December 2006 to June 2007 were divided according to MELD score in four groups. For each group, the influence of the match MELD on the probability of receiving a transplant was studied (Cox proportional hazards model). RESULTS: Laboratory-dependent significant differences in MELD score were demonstrated. Cox proportional hazards model showed a significant association between MELD score and the probability of organ allocation. The unadjusted hazard ratio for receiving a liver transplant was significantly different between group 2 and group 4 (group 2: MELD 19-24; group 4: MELD > 30). CONCLUSION: Laboratory-dependent significant differences in MELD score were observed between the six transplant centers. We demonstrated a significant association between the MELD score and the probability of organ allocation. The observed interlaboratory variation might yield a significant difference in organ allocation in patients with high MELD scores.

The prognostic value of renal resistance during hypothermic machine perfusion of deceased donor kidneys.

Vascular renal resistance (RR) during hypothermic machine perfusion (HMP) is frequently used in kidney graft quality assessment. However, the association between RR and outcome has never been prospectively validated. Prospectively collected RR values of 302 machine-perfused deceased donor kidneys of all types (standard and extended criteria donor kidneys and kidneys donated after cardiac death), transplanted without prior knowledge of these RR values, were studied. In this cohort, we determined the association between RR and delayed graft function (DGF) and 1-year graft survival. The RR (mmHg/mL/min) at the end of HMP was an independent risk factor for DGF (odds ratio 38.1 [1.56-934]; p = 0.026) [corrected] but the predictive value of RR was low, reflected by a c-statistic of the receiver operator characteristic curve of 0.58. The RR was also found to be an independent risk factor for 1-year graft failure (hazard ratio 12.33 [1.11-136.85]; p = 0.004). Determinants of transplant outcome are multifactorial in nature and this study identifies RR as an additional parameter to take into account when evaluating graft quality and estimating the likelihood of successful outcome. However, RR as a stand-alone quality assessment tool cannot be used to predict outcome with sufficient precision.

Considerations for patients awaiting heart transplantation.

The aim of this study is to provide a description of patients on the waiting list for heart transplants in Germany; the focus is on comparing the era after implementation of the new transplant law with the former era. This study used data from the Eurotransplant registry. The population consisted of all patients who registered for heart transplantation in Germany between January 1990 and May 2009. Patients were followed up to the earliest of the following events: heart transplantation, death, or end of the observation period. The actual mortality rates were calculated using a competing risk methodology. The proportion of patients on the waiting list aged 65 years or older has increased from 1.9 % in 1990 to 8.3 % in 1997, 7.8 % in 2000 and 12.6 % on December 31, 2008. The 1-year waiting list mortality rate, expressed as the proportion of patients who die within 1 year after being listed for heart transplantation decreased in the period 2001-2009 compared to the period 1991-2000. Patients registered in the period from 1991-2000 had a 25.9 % chance of dying prior to heart transplantation compared to 18.9 % for patients who were registered in the years 2001-2009. In the registration period 1981-1990, a transplant candidate had a 64.3 % chance of undergoing heart transplantation within the first year after being listed, while for patients who were registered in the period 2001-2009 this probability has been reduced to 40.2 %. Despite the fact that patient profiles have worsened and access to transplantation decreased, mortality rates of patients on the heart transplant waiting list have decreased. These data show that treatment of patients with advanced heart disease has improved in Germany.

How to recognize a suitable pancreas donor: a Eurotransplant study of preprocurement factors.

INTRODUCTION: Because of the increasing demand for pancreas transplantation, more marginal donors are offered to Eurotransplant. The aim of this study was to validate a donor quality score that would facilitate recognition of a suitable pancreas donor among all reported donors. MATERIALS AND METHODS: We analyzed all 3180 consecutively reported pancreas donors for the period between January 1, 2002 and June 30, 2005 and determined the influence of the preprocurement pancreas suitability score (P-PASS) on the acceptance of a pancreas. We defined a range and point weight for each variable based on clinical expertise and known literature. RESULTS: Multiple regression analysis using pancreas acceptance as an outcome variable identified P-PASS > or = 17 as a significant cutoff point (P < .001). Pancreata from donors with P-PASS > or = 17 were three times more likely to be refused. CONCLUSION: The donor score can help in screening for potential pancreas donors, where an ideal donor has a P-PASS < 17. Our data demonstrate that consideration of a combination of preprocurement factors can help identify a suitable pancreas donor. Therefore, we recommend that a pancreas donor score be calculated for each potential pancreas donor, and all donors with a P-PASS < 17 should be considered for pancreas donation.

The outcome of kidney grafts from multiorgan donors and kidney only donors.

From 1988 to 1994, 15356 renal cadaveric transplantations have been performed within the Eurotransplant area (Austria, Belgium, Germany, Luxembourg and The Netherlands); 8746 kidneys were obtained from multiorgan donors and 6610 from kidney only donors. To evaluate the impact of the procurement policy, multiorgan donor (MOD) versus kidney only donor (KOD), on renal graft survival, an observational study has been performed. Multivariate analysis using Cox's proportional hazards model served to quantify the role of the procurement policy on renal graft survival after adjustment for other prognostic factors. The kidneys obtained from MODs had a significantly better graft survival at 1, 3, and 5 years after transplantation than the kidneys obtained from KODs (85%, 75%, and 58% versus 78%, 68%, and 46% (P=0.0001). In the Cox model, patients transplanted with a KOD kidney had a 1.28 times higher risk of losing their graft than patients transplanted with a MOD kidney. This benefit in graft survival for MOD kidneys could not be explained by the fact that the MODs were younger and male, and that UW was used as preservation solution. A plausible explanation is that MODs, on average, because of the nonrenal transplants, are better supervised. We expect that optimal donor management will contribute to a better outcome of all renal grafts.

Analysis of the renal transplant waiting list: application of a parametric competing risk method.

BACKGROUND: The strong competition for scarce renal graft resources jeopardizes an individual patient's chances of a transplantation within a reasonable time scale. This study was undertaken to quantify these chances of receiving a transplant. METHODS: All patients registered for their first renal allograft between January 1980 and December 1993 (n=40,636) in Eurotransplant were selected. The influence of patient characteristics, such as age, HLA phenotype frequency, % panel-reactive antibodies, period of registration, and ABO blood group, on the waiting list outflow was studied. The competing risk method was applied, and Poisson models were built to estimate the risk factor effects. RESULTS: The chance of transplantation within 10 years after registration was overestimated by Kaplan-Meier (84%); using the competing risk method it was only 74%. The predicted chance for death on the waiting list was overestimated by 33% (45% Kaplan-Meier vs. 12% competing risk). A time-varying covariate effect on the chances of waiting list outflow was observed. Favorable factors for quick transplantation, such as blood group AB or a common HLA phenotype, were no longer seen to be driving forces for transplantation once 5 to 6 years of waiting time had been accrued. CONCLUSION: When multiple outcomes exist, Kaplan-Meier estimates should not be interpreted as survival rates, while competing risk estimates yield appropriate chances. A significantly decaying effect of the usual allocation parameters is observed with ongoing waiting time. This phenomenon is the statistical basis for redesigning allocation strategies. Organ exchange algorithms should have the potential to adapt to these time-varying effects.

Permanent detrimental effect of nonimmunological factors on long-term renal graft survival: a parsimonious model of time-dependency.

PURPOSE: We attempted to model and test the pattern of effects of prognostic factors on renal graft survival during the posttransplantation time course. PATIENTS AND METHODS: Patients who received a cadaveric kidney-only transplant between January 1990 and December 1995 in Eurotransplant, who received cyclosporine as induction therapy, and who had a complete follow-up at the time of analysis were included in the study (n= 10614). An index summarizing all covariate information was calculated and used for modeling the time-dependent effects with relation to graft failure. RESULTS: The immunological factors (HLA mismatch and % panel-reactive antibody) were seen to have a slowly decreasing negative effect on renal graft survival. The cold ischemic trauma (>24 hr) exerted a permanent detrimental effect on the grafts. The use of organs obtained from old donors was associated with a constant higher risk of graft loss. CONCLUSIONS: An analysis of determinants of human allograft dysfunction should also study the interaction between the effects and time. Nonimmunological factors had a constant detrimental effect on graft failure, whereas the impact of the immunological factors--although remaining important for late graft loss--very slowly decreased. In the context of marginal transplants, clustering of unfavorable factors should be avoided to prevent late graft losses.

Mortality rates after heart transplantation: how to compare center-specific outcome data?

BACKGROUND: Studies of outcome in cardiac transplantation have focused primarily on identifying patient- and donor-related factors associated with patient mortality. Less consideration has been given to the impact of the transplant center. This study was undertaken to assess variability in heart transplantation outcome in Eurotransplant centers to provide a framework for auditing. METHODS AND RESULTS: In a 2-year period, 1,401 adult patients underwent heart transplantation in 45 centers. The 1-year patient survival rate was 76% (95% CI, 74%-78%) with a range of 0% to 100% at the center level. The risk-adjusted center effect on mortality was estimated by calculating a standardized difference between the observed number of deaths 1 year after transplantation and the expected number of deaths based on the case mix. By assessing within- and between-center variations with empirical Bayes (EB) methods, after adjustment for all registered prognostic factors, an improved estimate of the true center effect was obtained. Compared with the standard risk-adjusted center effect method, fewer outlying centers were identified with the EB method. CONCLUSION: EB methods, because they are known to incorporate more information from the data, enable a more precise and realistic portrayal of heart transplant centers' performances, compared with other risk-adjusted center effect methods. In the context of auditing procedures, EB methods should preferably be used for the identification of centers that deviate significantly from quality standards.

Horseshoe kidney transplantation within the eurotransplant region: a case control study.

BACKGROUND: The horseshoe kidney is the most common anatomic renal variation, with an incidence of 1 in 600 to 800. It represents a fusion anomaly, usually of the lower poles. Horseshoe kidneys can be transplanted en bloc or after division of the renal isthmus. However, the great variation in origin, number, and size of renal arteries and veins leads to some reluctance to use horseshoe kidneys for transplantation. The aim of this study is to assess the results of horseshoe kidney transplantation. METHODS: All data concerning horseshoe kidney transplantations within the Eurotransplant region were collected and were divided into en bloc and split transplantations. A matched control group was defined, and the three groups were analyzed with respect to the occurrence of primary nonfunction, graft survival, patient survival, and finally posttransplant serum creatinine values. RESULTS: From 1983 to 2000, 8 horseshoe kidneys were transplanted en bloc and 26 were split and transplanted into 47 recipients. The results of these transplantations were compared with 110 transplantations in the control group. No significant differences among the three groups could be found, either in the short- or long-term posttransplant results. CONCLUSIONS: The results of horseshoe kidney transplantation, either en bloc or split, are equal to the posttransplant results of kidneys with a normal anatomy. Bearing in mind the shortage of donors, horseshoe kidneys should certainly be used for transplantation.

Lung transplant waiting list: differential outcome of type of end-stage lung disease, one year after registration.

BACKGROUND: Donor lung scarcity, distinct natural courses of the different types of end-stage lung diseases, and lung allocation schemes demand appropriate candidate acceptance for a lung transplant and time of listing. This study was undertaken to investigate the association between type of end-stage lung disease and outcome, 1 year after a lung transplant candidate was put on the waiting list. METHODS: From 1990 to 1995, 1376 adult patients were registered for a first lung (n = 1006) or heart-lung (n = 370) transplantation in Eurotransplant. All patients were followed for at least 1 year. For each type of end-stage lung disease (cystic fibrosis, pulmonary fibrosis, emphysema, pulmonary hypertension, congenital heart disease, and other), chances of transplantation, of death on the waiting list, and of removal for other reasons, 1 year after listing, were calculated with the competing risks method. A multivariate Cox regression model was used to assess the influence of the type of end-stage lung disease on the waiting list outflow among other prognostic variables. RESULTS: Lung transplant candidates with emphysema and with pulmonary fibrosis had the highest chance of a transplant; however, patients with pulmonary fibrosis had also the highest probability of dying while waiting, while the emphysema patients and those with the type "other" had the lowest probability. In the multivariate analysis, the type of end-stage lung disease appeared as an independent prognostic factor for both outcomes. Compared to the patients with cystic fibrosis (reference group), only patients with pulmonary fibrosis had a significantly higher chance of a transplant (RR = 1.50); the lowest chance of death for the emphysema and the "other" patients was confirmed (RR = 0.53 and RR = 0.51, respectively). Recipient size, ABO blood group, country and epoch of listing also had a significant impact on the transplant chance, while country of listing and recipient age were the other factors independently influencing the chance of dying on the waiting list. On the heart-lung waiting list, the type of end-stage lung disease solely affected the chance of death prior to transplant. Compared with cystic fibrosis, pulmonary fibrosis had a significantly higher risk (RR = 2.93), closely followed by pulmonary hypertension (RR = 2.57). Factors crucial for the chance of a heart-lung transplant were recipient size, ABO blood group and country of listing. CONCLUSIONS: The type of end-stage lung disease is a distinctive factor for predicting survival on the lung and heart-lung transplant waiting list, and should be taken into account whenever assessing waiting list outcomes. When developing lung allocation schemes, it is medically justified to incorporate the type of end-stage lung disease.

Listing for lung transplantation: life expectancy and transplant effect, stratified by type of end-stage lung disease, the Eurotransplant experience.

BACKGROUND: Increased referral for lung transplantation, persistent shortage of donor lungs, and moderate transplant outcome call not only for adequate listing criteria, but also for an optimal allocation scheme. We used global cohort survival after listing and survival benefit from transplantation to study the effect of a lung allocation scheme, primarily driven by waiting time, on the different types of end-stage lung disease. METHODS: We followed all adult patients consecutively listed for first, lung-only transplantation between 1990 and 1996 (n = 1,208) for at least 2 years, with an additional 2-year follow-up after transplantation (n = 744). We used the competing risk method, the Kaplan-Meier method, and a time-dependent non-proportional hazards model to analyze waiting-list outcome and global mortality after listing, post-transplant survival, and transplant effect, respectively. Each analysis was stratified for type of end-stage lung disease. RESULTS: At 2 years, 57% of the total cohort had received lung transplants, whereas 25% had died on the waiting list. The 2-year survival post-transplant was 55%. The global mortality of the cohort, since listing, amounted to 46% at 2 years. Compared with continued waiting, patients experienced benefit from transplantation by Day 100, which lasted until the end of the 2-year analysis period. We noticed the highest global mortality rates for patients with pulmonary fibrosis and pulmonary hypertension (54% and 52%); emphysema patients had the lowest (38%). Patients with pulmonary fibrosis and cystic fibrosis had much earlier benefit from transplantation, 55 and 90 days, respectively. Transplantation also benefited emphysema patients by Day 260. CONCLUSIONS: Lung transplantation conferred transplant benefit in a Western European cohort of adults, in particular for patients with pulmonary fibrosis and cystic fibrosis, but also for patients with emphysema. The global survival rate, reflecting the real life expectancy for a newly listed transplant candidate, is poor for patients with pulmonary fibrosis and pulmonary hypertension. Allocation algorithms that lessen the impact of waiting time and take into account the type of end-stage lung disease should be developed.

Iso-risk curves as a tool for clinical decision-making: donor factors and medical urgency in cardiac transplantation.

UNLABELLED: BACKGROUND; No significant improvement of overall graft survival in cardiac transplantation has occurred during the past decade, notwithstanding the identification of several prognostic donor and recipient risk factors. By translating multivariate results into iso-risk curves plots, stratified for medical urgency, we attempt to present results in a more practical manner, to be used as guidelines at the time of donor heart offer and of allocation. METHODS: We analyzed all first heart-only transplants performed in adults and carried out between January 1, 1997, and June 30, 1998 (N = 1120). Before transplant, 687 patients were at home, 233 on hospital wards, and 200 on the intensive care unit. The overall Cox model yielded 5 independent factors associated with 1-year graft outcome: donor age, donor:recipient weight ratio, medical urgency, end-stage heart disease, and transplant country. We used the significant donor variables of donor age and donor:recipient weight ratio for the iso-risk curves; we calculated relative risks for all combinations of donor age and donor:recipient weight ratio. We obtained iso-risk curves by linking equal relative risks. RESULTS: All iso-risk curves showed that with older donor age, the donor:recipient weight ratio must be higher to obtain the same relative risk for all 3 medical urgency groups. The more urgent the heart transplant candidate, the higher the course of the iso-risk curve for all donor ages. CONCLUSIONS: Iso-risk curve is an elegant tool for presenting multivariate analyses in a more practical and patient-oriented manner. The more understandable prognostic factors become the more likely we are to achieve better results in cardiac transplantation and to use more optimally donor hearts. As an example, we have demonstrated the interaction between donor age, donor:recipient size ratio, and medical urgency.

In vitro reactivity of allospecific cytotoxic T lymphocytes does not explain the taboo phenomenon.

Matching for human leucocyte antigens (HLA) is important for graft survival in kidney transplantation. Nevertheless, most patients receive a kidney graft with multiple HLA mismatches. Some of these mismatches seem to be more harmful than others. By studying the effect of single HLA mismatches in the context of the patients' own HLA, we have previously identified donor/recipient combinations with a significantly higher incidence of early graft failure, the so-called taboo combinations. In the present study we investigated whether a higher cytotoxic T lymphocyte (CTL) response towards taboo mismatches may be involved in this phenomenon. CTL reactivity was determined both in taboo and control combinations by in vitro CTL precursor assays, using peripheral blood mononuclear cells and proximal tubular epithelial cells as target cells. Inhibition studies with CD8-antibody as well as Cyclosporin A were performed to identify high avidity and primed CTLs. Furthermore, in committed CTLp assays indirect recognition of the taboo mismatch was tested using synthetic peptides. The CTL precursor frequencies in taboo combinations were always lower than the CTL precursor frequencies in control combinations. No difference in avidity and activation status of the CTLs could be detected when taboo combinations were compared with the controls. In the committed CTLp assays no reactivity towards any of the synthetic peptides was observed. The significantly poorer graft survival of taboo combinations cannot be explained by a higher number of donor-specific CTLs. Furthermore, the avidity or activation status of these CTLs does not provide a clue to the taboo phenomenon.

Propranolol in conscious spontaneously hypertensive rats. II. Disposition after subcutaneous and intracerebroventricular administration.

The disposition of dl-propranolol was studied in spontaneously hypertensive rats (SHR), both after subcutaneous (s.c.) and intracerebroventricular (i.c.v.) injection of 1 mg/kg. 1. Upon s.c. injection propranolol appeared rapidly in plasma. A maximum concentration of 374 +/- 33 ng/ml (N = 10) was reached 5 min after injection. After a distribution phase with a half-life of t 1/2 alpha = 17 min propranolol was eliminated with a t 1/2 beta = 59 min. 2. Both propranolol and its metabolites were taken up rapidly into all tissues studied. Highest concentrations (10.4 +/- 1.5 micrograms/g, N = 5) were found in lungs 30 min after injection. 3. Neither propranolol nor its metabolites accumulated in any of the tissues examined. 4. Upon i.c.v. injection of propranolol, a maximal concentration of 573 +/- 47 ng/ml (N = 3) was reached in plasma already 2 min after injection. In this case t 1/2 alpha was 13 min and t 1/2 beta was 80 min. 5. Dialysis experiments indicated that propranolol is bound to plasma proteins for 92% in the concentration range of 20--100 ng/ml. With increasing concentrations binding diminishes progressively. At the highest concentration tested (345 ng/ml) only 76% was bound. It is concluded that s.c. and i.c.v. injection of an identical dose of propranolol gives a similar plasma concentration-time profile. Moreover, it is suggested that the pharmacokinetic behaviour of propranolol in SHR does not explain the delayed antihypertensive effect of this drug.

Effect of receiving a heart transplant: analysis of a national cohort entered on to a waiting list, stratified by heart failure severity. Comparative Outcome and Clinical Profiles in Transplantation (COCPIT) Study Group.

OBJECTIVE: To determine whether there is a survival benefit associated with cardiac transplantation in Germany. DESIGN: Prospective observational cohort study. SETTING: All 889 adult patients listed for a first heart transplant in Germany in 1997. MAIN OUTCOME MEASURE: Mortality, stratified by heart failure severity. RESULTS: Within 1 year after listing, patients with a predicted high risk had the highest global death rate (51% v 32% and 29% for medium and low risk patients respectively; P<0.0001), had the highest risk of dying on the waiting list (32% v 20% and 20%; P=0.0003), and were more likely to receive a transplant (48% v 45% and 41%; P=0.01). Differences between the risk groups in outcome after transplantation did not reach significance (P=0.2). Transplantation was not associated with a reduction in mortality risk for the total cohort, but it did provide a survival benefit for the high risk group. CONCLUSION: Cardiac transplantation in Germany is currently associated with a survival benefit only in patients with a predicted high risk of dying on the waiting list. Patients with a predicted low or medium risk have no reduction in mortality risk associated with transplantation; they should be managed with organ saving approaches rather than transplantation.

[The importance of different pig diseases in the Netherlands]. / Het belang van de verschillende varkensziekten in Nederland.

As part of the project 'Clean pigs', IPG Institute for Pig Genetics BV made an inventory of the impact of different diseases on the Dutch pig industry. An expert panel assessed the importance of the different diseases with regard to public health, farm economy, the pig sector and export sales. The possibilities for the diagnosis of the different pathogens were listed and the goal for the next years, was set. Diseases were classified into three categories, according to their importance for the Dutch pig industry (Table 2). The diseases that can be eradicated are Salmonella (only specific strains), Pasteurella multocida DNT + PAR), Actinobacillus pleuropneumoniae, Haematopinus suis (lice) and Sarcoptes scabei (var. suis) (mange). National introduction of list A en most list B diseases of the OIE classification must be prevented.

[Improved pig health with farm management systems. Project 'Beautiful stream of pigs' 21]. / Gezondheidsverbetering in de varkenshouderij door toepassing van bedrijfssystemen. Project 'Schone varkensstromen' 21.

As part of the project 'Clean pigs', an inventory was made of the different pig farm management systems described in the literature. These systems were evaluated for their potential use in improving animal health, focusing on the pathogens important in the Netherlands. The most promising systems for the control and/or eradication of pig pathogens in the Netherlands can be divided into two groups (with decreasing effect): I. Eradication from an existing positive population. The best systems for this are Embryo Transplantation (ET), Specific-Pathogen Free pigs (SPF), Piglet Snatching and Segregated Weaning (SW). II. Strategic veterinary and breeding strategies. The best systems for this are Freeze infection, test and removal, Test and removal, Vaccination, Medical elimination, Strategic medication and Genetic resistance. Farm systems can be a big help when trying to improve animal health, but the 'biosecurity' measures on the farm are at least of equal importance.