Graft-versus-host disease (GVHD) remains a major clinical drawback of allogeneic hematopoietic st... more Graft-versus-host disease (GVHD) remains a major clinical drawback of allogeneic hematopoietic stem cell transplantation (HSCT). Here, we investigated how the stress responsive heme catabolizing enzyme heme oxygenase-1 (HO-1, encoded by HMOX1) regulates GVHD in response to allogeneic hematopoietic stem cell transplantation in mice and humans. We found that deletion of the Hmox1 allele, specifically in the myeloid compartment of mouse donor bone marrow, promotes the development of aggressive GVHD after allogeneic transplantation. The mechanism driving GVHD in mice transplanted with allogeneic bone marrow lacking HO-1 expression in the myeloid compartment involves enhanced T cell alloreactivity. The clinical relevance of these observations was validated in two independent cohorts of HSCT patients. Individuals transplanted with hematopoietic stem cells from donors carrying a long homozygous (GT)n repeat polymorphism (L/L) in the HMOX1 promoter, which is associated with lower HO-1 expre...
Background Subgroups of precarious populations such as homeless people are more exposed to infect... more Background Subgroups of precarious populations such as homeless people are more exposed to infection and at higher risk of developing severe forms of COVID-19 compared to the general population. Many of the recommended prevention measures, such as social distancing and self-isolation, are not feasible for a population living in shelters characterised by physical proximity and a high population density. The objective of the study was to describe SARS-CoV-2 infection prevalence in homeless shelters in Brussels (Belgium), and to identify risk factors and infection control practices associated with SARS-CoV-2 positivity rates. Methods A total of 1994 adults were tested by quantitative PCR tests in 52 shelters in Brussels (Belgium) between April and June, 2020, in collaboration with Doctors of the World. SARS-CoV-2 prevalence is here described site by site, and we identify risk factors associated with SARS-CoV-2 positivity rates. We also investigate associations between seropositivity an...
Diagnosis of tuberculosis (TB) in children remains challenging due to unspecific clinical present... more Diagnosis of tuberculosis (TB) in children remains challenging due to unspecific clinical presentation and low bacillary load. In low TB incidence countries, most cases are diagnosed by a contact screening strategy after exposure to an index TB case. Due to the severity of TB in young children, the priority is to determine whether a child is infected or not, whereas differential diagnosis between active TB (aTB) and latent TB constitutes a second step. In Belgium, a low TB incidence country, we prospectively included 47 children with a defined M. tuberculosis infection status (12 children with aTB, 18 with latent TB, and 17 uninfected) (exploratory cohort), and determined the optimal combinations of cytokines secreted by their peripheral blood mononuclear cells in response to a 5-days in vitro stimulation with four different mycobacterial antigens, in an attempt to classify the children according to their infectious status. Correct identification of all infected children was obtaine...
Background The underlying mechanisms of perinatal health inequalities remain under-researched. A ... more Background The underlying mechanisms of perinatal health inequalities remain under-researched. A possible explanation is inadequate access to healthcare services and suboptimal care for certain groups. To explore this, our study analyses the mothers’ prenatal care trajectories and experiences of care in relation to socioeconomic and migration characteristics. Methods A survey of 750 migrant and non-migrant mothers interviewed in 4 maternity wards in Brussels. Based on the adaptation of the Migrant-Friendly Maternity Care Questionnaire, the survey focuses on mothers with a Belgian, North African (NA) and Subsaharan African (SSA) nationality. The data are analysed through descriptive statistics and logistic regression. Results This ongoing survey has a high response rate (83%). Preliminary subsample analyses (n = 276) show that the socioeconomic profiles of mothers vary substantially depending on nationality, with mothers from NA generally having a lower level of education, and mother...
Nephrology, dialysis, transplantation : official publication of the European Dialysis and Transplant Association - European Renal Association, Jan 9, 2018
Urinary tract infection is the most common infection among kidney transplant recipients (KTRs). M... more Urinary tract infection is the most common infection among kidney transplant recipients (KTRs). Many transplant physicians fear that host compromise will allow low-virulence strains to cause pyelonephritis in KTRs, so they often treat asymptomatic bacteriuria with antibiotics. Identification of the host/microbe factors that determine the clinical presentation (i.e. pyelonephritis versus asymptomatic bacteriuria) once an Escherichia coli strain enters a KTRs bladder could inform management decisions. We prospectively collected all E. coli isolates causing either pyelonephritis or asymptomatic bacteriuria in KTRs at our institution (December 2012-June 2015). Whole-genome sequencing was used to assess bacterial characteristics (carriage of 48 virulence genes and phylogenetic and clonal background). Host parameters were also collected. We analysed 72 bacteriuria episodes in 54 KTRs (53 pyelonephritis, 19 asymptomatic bacteriuria). The pyelonephritis and asymptomatic bacteriuria isolates...
This is one of the first studies to compare the frequencies of different human leucocyte antigen ... more This is one of the first studies to compare the frequencies of different human leucocyte antigen (HLA) class I and II alleles and haplotype HLA-DRB1*15-DQB1*06 in a cohort of 119 patients with multiple sclerosis (MS) and a cohort of 124 healthy controls in Belgium. An association with MS was found for the HLA-DRB1*15 (odds ratio [OR] 2.60 [95% confidence interval (CI) 1.51-4.50]) and HLA-DQB1*06 (OR 1.97 [95% CI 1.18-3.29]) alleles, and for haplotype DRB1*15-DQB1*06 (OR 2.63 [95% CI 1.52-4.56]). The HLA-B*07 allele also tended to be more frequent in MS patients (OR 1.46 [95% CI 0.80-2.65]) and more frequent among MS patients with than in those without the HLA-DRB1*15 allele (26/54 [48.1%] versus 6/65 [9.2%]; p value <0.0001). Other alleles were underrepresented in MS patients, such as the HLA-DRB1*07 (OR 0.39 [95% CI 0.21-0.73]) and HLA-A*02 (OR 0.56 [95% CI 0.34-0.94]), showing a protective role against the disease. The HLA-B*44 (OR 0.58 [95% CI 0.31-1.09]) and HLA-DRB1*04 (OR 0...
Cardiac surgery-associated acute kidney injury (CSA-AKI) is a common complication and is associat... more Cardiac surgery-associated acute kidney injury (CSA-AKI) is a common complication and is associated with the poorest outcomes. Therefore, early prediction of CSA-AKI remains a major issue. Severity scores such as the STS score could estimate the risk of AKI preoperatively. The main objective of this study was to evaluate the risk factors of on-pump CSA-AKI and to assess the performance of the STS score in order to predict CSA-AKI. We identified 252 patients with on-pump cardiac surgery, and the STS score was defined retrospectively. AKI occurred in 14.6% (n = 37/252) of patients and renal replacement therapy was required in 21.6% of AKI (n = 8/37). CSA-AKI was associated with 35.1% in-hospital mortality (vs. 1.4%) and nearly doubled length of stay (14.5 vs. 8.0 d). The risk of CSA-AKI was mainly determined by preoperative morbidities such as chronic kidney disease, peripheral vascular disease, and severe congestive heart failure. Long cardio-pulmonary bypass time was also a determinant. CSA-AKI + patients exhibited higher STS renal risk (5.6% vs. 2.0%; p &amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;lt; 0.0001), resulting in a good discrimination between AKI + and AKI - patients (area under curve [AUC] 0.80). Interestingly, a basal renal function ≤55 ml/min/1.73m(2) was as good as the STS score to predict CSA-AKI (AUC 0.75; P 0.26). On-pump CSA-AKI was observed in nearly 15% of cases and was associated with poorer outcomes. Interestingly, the risk of CSA-AKI could be estimated preoperatively, thanks to the basal renal function, which exhibited an equal performance to the STS score.
Increasing studies show that immigrants have different perinatal health outcomes compared to nati... more Increasing studies show that immigrants have different perinatal health outcomes compared to native women. Nevertheless, we lack a systematic examination of the combined effects of immigrant status and socioeconomic factors on perinatal outcomes. Our objectives were to analyse national Belgian data to determine 1) whether socioeconomic status (SES) modifies the association between maternal nationality and perinatal outcomes (low birth weight and perinatal mortality); 2) the effect of adopting the Belgian nationality on the association between maternal foreign nationality and perinatal outcomes. This study is a population-based study using the data from linked birth and death certificates from the Belgian civil registration system. Data are related to all singleton births to mothers living in Belgium between 1998 and 2010. Perinatal mortality and low birth weight (LBW) were estimated by SES (maternal education and parental employment status) and by maternal nationality (at her own bi...
Nephrology, dialysis, transplantation : official publication of the European Dialysis and Transplant Association - European Renal Association, Jun 12, 2016
Kidney recipients maintaining a prolonged allograft survival in the absence of immunosuppressive ... more Kidney recipients maintaining a prolonged allograft survival in the absence of immunosuppressive drugs and without evidence of rejection are supposed to be exceptional. The ERA-EDTA-DESCARTES working group together with Nantes University launched a European-wide survey to identify new patients, describe them and estimate their frequency for the first time. Seventeen coordinators distributed a questionnaire in 256 transplant centres and 28 countries in order to report as many 'operationally tolerant' patients (TOL; defined as having a serum creatinine <1.7 mg/dL and proteinuria <1 g/day or g/g creatinine despite at least 1 year without any immunosuppressive drug) and…
Graft-versus-host disease (GVHD) remains a major clinical drawback of allogeneic hematopoietic st... more Graft-versus-host disease (GVHD) remains a major clinical drawback of allogeneic hematopoietic stem cell transplantation (HSCT). Here, we investigated how the stress responsive heme catabolizing enzyme heme oxygenase-1 (HO-1, encoded by HMOX1) regulates GVHD in response to allogeneic hematopoietic stem cell transplantation in mice and humans. We found that deletion of the Hmox1 allele, specifically in the myeloid compartment of mouse donor bone marrow, promotes the development of aggressive GVHD after allogeneic transplantation. The mechanism driving GVHD in mice transplanted with allogeneic bone marrow lacking HO-1 expression in the myeloid compartment involves enhanced T cell alloreactivity. The clinical relevance of these observations was validated in two independent cohorts of HSCT patients. Individuals transplanted with hematopoietic stem cells from donors carrying a long homozygous (GT)n repeat polymorphism (L/L) in the HMOX1 promoter, which is associated with lower HO-1 expre...
Background Subgroups of precarious populations such as homeless people are more exposed to infect... more Background Subgroups of precarious populations such as homeless people are more exposed to infection and at higher risk of developing severe forms of COVID-19 compared to the general population. Many of the recommended prevention measures, such as social distancing and self-isolation, are not feasible for a population living in shelters characterised by physical proximity and a high population density. The objective of the study was to describe SARS-CoV-2 infection prevalence in homeless shelters in Brussels (Belgium), and to identify risk factors and infection control practices associated with SARS-CoV-2 positivity rates. Methods A total of 1994 adults were tested by quantitative PCR tests in 52 shelters in Brussels (Belgium) between April and June, 2020, in collaboration with Doctors of the World. SARS-CoV-2 prevalence is here described site by site, and we identify risk factors associated with SARS-CoV-2 positivity rates. We also investigate associations between seropositivity an...
Diagnosis of tuberculosis (TB) in children remains challenging due to unspecific clinical present... more Diagnosis of tuberculosis (TB) in children remains challenging due to unspecific clinical presentation and low bacillary load. In low TB incidence countries, most cases are diagnosed by a contact screening strategy after exposure to an index TB case. Due to the severity of TB in young children, the priority is to determine whether a child is infected or not, whereas differential diagnosis between active TB (aTB) and latent TB constitutes a second step. In Belgium, a low TB incidence country, we prospectively included 47 children with a defined M. tuberculosis infection status (12 children with aTB, 18 with latent TB, and 17 uninfected) (exploratory cohort), and determined the optimal combinations of cytokines secreted by their peripheral blood mononuclear cells in response to a 5-days in vitro stimulation with four different mycobacterial antigens, in an attempt to classify the children according to their infectious status. Correct identification of all infected children was obtaine...
Background The underlying mechanisms of perinatal health inequalities remain under-researched. A ... more Background The underlying mechanisms of perinatal health inequalities remain under-researched. A possible explanation is inadequate access to healthcare services and suboptimal care for certain groups. To explore this, our study analyses the mothers’ prenatal care trajectories and experiences of care in relation to socioeconomic and migration characteristics. Methods A survey of 750 migrant and non-migrant mothers interviewed in 4 maternity wards in Brussels. Based on the adaptation of the Migrant-Friendly Maternity Care Questionnaire, the survey focuses on mothers with a Belgian, North African (NA) and Subsaharan African (SSA) nationality. The data are analysed through descriptive statistics and logistic regression. Results This ongoing survey has a high response rate (83%). Preliminary subsample analyses (n = 276) show that the socioeconomic profiles of mothers vary substantially depending on nationality, with mothers from NA generally having a lower level of education, and mother...
Nephrology, dialysis, transplantation : official publication of the European Dialysis and Transplant Association - European Renal Association, Jan 9, 2018
Urinary tract infection is the most common infection among kidney transplant recipients (KTRs). M... more Urinary tract infection is the most common infection among kidney transplant recipients (KTRs). Many transplant physicians fear that host compromise will allow low-virulence strains to cause pyelonephritis in KTRs, so they often treat asymptomatic bacteriuria with antibiotics. Identification of the host/microbe factors that determine the clinical presentation (i.e. pyelonephritis versus asymptomatic bacteriuria) once an Escherichia coli strain enters a KTRs bladder could inform management decisions. We prospectively collected all E. coli isolates causing either pyelonephritis or asymptomatic bacteriuria in KTRs at our institution (December 2012-June 2015). Whole-genome sequencing was used to assess bacterial characteristics (carriage of 48 virulence genes and phylogenetic and clonal background). Host parameters were also collected. We analysed 72 bacteriuria episodes in 54 KTRs (53 pyelonephritis, 19 asymptomatic bacteriuria). The pyelonephritis and asymptomatic bacteriuria isolates...
This is one of the first studies to compare the frequencies of different human leucocyte antigen ... more This is one of the first studies to compare the frequencies of different human leucocyte antigen (HLA) class I and II alleles and haplotype HLA-DRB1*15-DQB1*06 in a cohort of 119 patients with multiple sclerosis (MS) and a cohort of 124 healthy controls in Belgium. An association with MS was found for the HLA-DRB1*15 (odds ratio [OR] 2.60 [95% confidence interval (CI) 1.51-4.50]) and HLA-DQB1*06 (OR 1.97 [95% CI 1.18-3.29]) alleles, and for haplotype DRB1*15-DQB1*06 (OR 2.63 [95% CI 1.52-4.56]). The HLA-B*07 allele also tended to be more frequent in MS patients (OR 1.46 [95% CI 0.80-2.65]) and more frequent among MS patients with than in those without the HLA-DRB1*15 allele (26/54 [48.1%] versus 6/65 [9.2%]; p value <0.0001). Other alleles were underrepresented in MS patients, such as the HLA-DRB1*07 (OR 0.39 [95% CI 0.21-0.73]) and HLA-A*02 (OR 0.56 [95% CI 0.34-0.94]), showing a protective role against the disease. The HLA-B*44 (OR 0.58 [95% CI 0.31-1.09]) and HLA-DRB1*04 (OR 0...
Cardiac surgery-associated acute kidney injury (CSA-AKI) is a common complication and is associat... more Cardiac surgery-associated acute kidney injury (CSA-AKI) is a common complication and is associated with the poorest outcomes. Therefore, early prediction of CSA-AKI remains a major issue. Severity scores such as the STS score could estimate the risk of AKI preoperatively. The main objective of this study was to evaluate the risk factors of on-pump CSA-AKI and to assess the performance of the STS score in order to predict CSA-AKI. We identified 252 patients with on-pump cardiac surgery, and the STS score was defined retrospectively. AKI occurred in 14.6% (n = 37/252) of patients and renal replacement therapy was required in 21.6% of AKI (n = 8/37). CSA-AKI was associated with 35.1% in-hospital mortality (vs. 1.4%) and nearly doubled length of stay (14.5 vs. 8.0 d). The risk of CSA-AKI was mainly determined by preoperative morbidities such as chronic kidney disease, peripheral vascular disease, and severe congestive heart failure. Long cardio-pulmonary bypass time was also a determinant. CSA-AKI + patients exhibited higher STS renal risk (5.6% vs. 2.0%; p &amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;lt; 0.0001), resulting in a good discrimination between AKI + and AKI - patients (area under curve [AUC] 0.80). Interestingly, a basal renal function ≤55 ml/min/1.73m(2) was as good as the STS score to predict CSA-AKI (AUC 0.75; P 0.26). On-pump CSA-AKI was observed in nearly 15% of cases and was associated with poorer outcomes. Interestingly, the risk of CSA-AKI could be estimated preoperatively, thanks to the basal renal function, which exhibited an equal performance to the STS score.
Increasing studies show that immigrants have different perinatal health outcomes compared to nati... more Increasing studies show that immigrants have different perinatal health outcomes compared to native women. Nevertheless, we lack a systematic examination of the combined effects of immigrant status and socioeconomic factors on perinatal outcomes. Our objectives were to analyse national Belgian data to determine 1) whether socioeconomic status (SES) modifies the association between maternal nationality and perinatal outcomes (low birth weight and perinatal mortality); 2) the effect of adopting the Belgian nationality on the association between maternal foreign nationality and perinatal outcomes. This study is a population-based study using the data from linked birth and death certificates from the Belgian civil registration system. Data are related to all singleton births to mothers living in Belgium between 1998 and 2010. Perinatal mortality and low birth weight (LBW) were estimated by SES (maternal education and parental employment status) and by maternal nationality (at her own bi...
Nephrology, dialysis, transplantation : official publication of the European Dialysis and Transplant Association - European Renal Association, Jun 12, 2016
Kidney recipients maintaining a prolonged allograft survival in the absence of immunosuppressive ... more Kidney recipients maintaining a prolonged allograft survival in the absence of immunosuppressive drugs and without evidence of rejection are supposed to be exceptional. The ERA-EDTA-DESCARTES working group together with Nantes University launched a European-wide survey to identify new patients, describe them and estimate their frequency for the first time. Seventeen coordinators distributed a questionnaire in 256 transplant centres and 28 countries in order to report as many 'operationally tolerant' patients (TOL; defined as having a serum creatinine <1.7 mg/dL and proteinuria <1 g/day or g/g creatinine despite at least 1 year without any immunosuppressive drug) and…
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Papers by Judith Racapé