Newborn screening for sickle cell disease in Kisangani, Democratic Republic of the Congo: an update

BACKGROUND

Neonatal screening is the first action necessary to identify children with sickle cell disease (SCD) and thus ensure their care. Using rapid tests to give an immediate result to families is a new resilient approach of great interest. These two aspects are essential for establishing an adequate health policy for this disease. This study was undertaken in Kisangani to update the current incidence of neonatal SCD.

METHODS

Heel prick blood samples of 1432 babies born from different racial groups of parents living in Kisangani were collected at birth and screened using a point of care test, i.e. the HemoTypeSC^TM.

RESULTS

The incidence at birth was 2.2% (n = 31; 95% CI: [1.5%-3.1%]) for HbSS homozygosity and 21% (n = 303; 95% CI: [19%-23%]) for HbAS heterozygosity. Compared to a previous study in 2010; the incidence at the birth of the HbSS form has doubled, while that of the heterozygous form HbAS remained almost unchanged. The inter-ethnic incidence of HbSS among the five top-represented ethnic groups was significant (<0.001).

CONCLUSION

The prevalence of homozygote form has doubled compared to the 0.96% reported in 2010. Setting up a neonatal screening program and an awareness unit is necessary to assess the need for care services correctly.

Sickle cell disease landscape and challenges in the EU: the ERN-EuroBloodNet perspective

Sickle cell disease is a hereditary multiorgan disease that is considered rare in the EU. In 2017, the Rare Diseases Plan was implemented within the EU and 24 European Reference Networks (ERNs) were created, including the ERN on Rare Haematological Diseases (ERN-EuroBloodNet), dedicated to rare haematological diseases. This EU initiative has made it possible to accentuate existing collaborations and create new ones. The project also made it possible to list all the needs of people with rare haematological diseases not yet covered health-care providers in the EU to allow optimised care of individuals with rare pathologies, including sickle cell disease. This Viewpoint is the result of joint work within 12 EU member states (ie, Belgium, Cyprus, Denmark, France, Germany, Greece, Ireland, Italy, Portugal, Spain, Sweden, and The Netherlands), all members of the ERN-EuroBloodNet. We describe the role of the ERN-EuroBloodNet to improve the overall approach to and the management of individuals with sickle cell disease in the EU through specific on the pooling of expertise, knowledge, and best practices; the development of training and education programmes; the strategy for systematic gathering and standardisation of clinical data; and its reuse in clinical research. Epidemiology and research strategies from ongoing implementation of the Rare Anaemia Disorders European Epidemiological Platform is depicted.

Screening for hereditary spherocytosis in daily practice: what is the best algorithm using erythrocyte and reticulocyte parameters?

Hereditary spherocytosis (HS) is the most common inherited chronic haemolytic anaemia in Northern Europe. During the last decade, additional erythrocyte and reticulocyte parameters have been developed on last-generation haematology analysers, leading to many publications about their effectiveness as a HS screening tool. For the first time on an independent cohort, we evaluated and compared the effectiveness of six published algorithms for the screening of HS using the UniCel DxH800 (Beckman-Coulter) and the XN-9000 (Sysmex) and determined which algorithm could be the most suitable in our daily clinical practice. A total of 95 EDTA samples were analysed prospectively on both haematology analysers. These included 11 confirmed HS patients and 84 non-HS patients. The specific reticulocyte parameters used on the DxH800 were mean reticulocyte volume, immature reticulocyte fraction and mean sphered cell volume, and on the XN-9000 were hypohaemoglobinised erythrocytes, microcytic erythrocytes and immature reticulocyte fraction. The three algorithms using parameters specific to Beckman-Coulter analysers provided a sensitivity of 100% with various specificities, ranging from 7.1 to 73.8%. The three algorithms published based on the parameters specific to Sysmex showed much lower performances, i.e. out of the 11 patients with HS, between one to five patients were screened as negative for HS. However, 100% sensitivity and specificity were reached using the EMA binding test concomitantly with those three algorithms. The algorithms using reticulocyte and erythrocyte parameters offered by the recent analysers are promising options as a HS first-tier screening tool. Nevertheless, they must be evaluated by each laboratory on their own analyser before implementation.

Influence of diabetes and hypercholesterolemia on laboratory methods for hereditary spherocytosis diagnosis

INTRODUCTION

Hereditary spherocytosis (HS) is characterized by decreased erythrocyte deformability resulting in hemolytic anemia. This is a heterogeneous disease regarding underlying protein deficiency, disease severity, age at diagnosis and clinical course. Although largely considered as pediatric disease, HS could be initially diagnosed also in elder patients as a result of gallstones or splenomegaly fortuitous finding. Concurrently, common adulthood metabolic disorders like diabetes or dyslipidemia are also known to impair RBC rheology and deformability. Therefore, we aimed to investigate if these diseases affect the screening and diagnostic tools used for HS diagnosis.

METHODS

We applied our workflow for HS diagnosis on 95 pathological samples: 29 patients with diabetes, 20 with hypercholesterolemia, 17 with dyslipidemia, 6 with hypertriglyceridemia, 23 with metabolic syndrome (MS). Thus, a total of 73 samples were analyzed by automated reticulocyte analysis, 52 by cryohemolysis test, and 41 by ektacytometry osmoscan analysis as we used two out of the three tests for each individual sample.

RESULTS

Applying our screening algorithm based on automated reticulocyte indices, a total of 4 samples (4.2%): one sample (5%) from the diabetes group and three samples (16.7%) from the MS group, positioned into the HS zone. However, no significant difference was found between any of the pathological groups and the controls for the cryohemolysis test or the osmoscan.

CONCLUSION

While diabetes and hypercholesterolemia are pathologic conditions known to present with decreased erythrocyte deformability and disturbed rheology, their possible concomitant presence with HS would not interfere with the screening and confirmatory laboratory methods.

Co-occurrence of sickle cell disease and oculocutaneous albinism in a Congolese patient: a case report

BACKGROUND

Sickle cell disease and oculocutaneous albinism are rare autosomal recessive disorders both related to mutations on chromosome 11. The diagnosis of patients suffering from both pathologies is necessary to enable dedicated monitoring of any complications at the ophthalmic and skin level. However, few cases are described in the literature.

CASE PRESENTATION

A 14-month-old Congolese male child affected by oculocutaneous albinism, presented with pallor and jaundice. Blood indices revealed severe hemolytic anemia, which led to the diagnosis of sickle cell disease. The patient received a blood transfusion and close follow-up.

CONCLUSIONS

The co-inheritance of sickle cell disease and oculocutaneous albinism is a reality in the Democratic Republic of Congo, although it is rarely described. Given the current state of our knowledge, specific surveillance, specifically regarding cutaneous and ophthalmological complications, should be offered in this particular population. To enable this dedicated follow-up, sensitization to screening for sickle cell anemia in albino individuals should be carried out.

Improvement of SCD morbimortality in children: experience in a remote area of an African country

BACKGROUND

Sickle cell disease (SCD) is a public health problem in the Democratic Republic of Congo. While reference sickle cell centers have been implemented in capital cities of African countries and have proven to be beneficial for SCD patients. In the Democratic Republic of Congo, they have never been set up in remote areas for families with low or very low sources of income.

METHOD

A cohort of 143 children with SCD aged 10 years old (IQR (interquartile range): 6-15 years) (sex ratio male/female = 1.3) were clinically followed for 12 months without any specific intervention aside from the management of acute events, and then for 12 months with a monthly medical visit, biological follow-up, and chemoprophylaxis (folic acid/penicillin), adequate fluids and malaria prevention.

RESULTS

The median age of patients at the diagnosis of SCD was 2 years (IQR: 1-5). The implementation of standardized and regular follow-ups in a new sickle cell reference center in a remote city showed an increase in the annual mean hemoglobin level from 50 to 70 g/L (p = 0.001), and a decrease in the lymphocyte count and spleen size (p < 0.001). A significant decrease (p < 0.001) in the average annual number of hospitalizations and episodes of vaso-occlusive crises, blood transfusions, infections, and acute chest syndromes were also observed.

CONCLUSIONS

The creation of a sickle cell reference center and the regular follow-up of children with sickle cell disease are possible and applicable in the context of a remote city of an African country and represent simple and accessible measures that can reduce the morbimortality of children with sickle cell disease.

[Acceptability of neonatal screening of the sickle cell disease during the pandemic of COVID-19 in Kisangani, Democratic Republic of the Congo]

Introduction

l´implémentation du dépistage néonatal de la drépanocytose pendant la pandémie de coronavirus (COVID-19) représente un défi majeur en République Démocratique du Congo (RDC). La présente étude vise à déterminer si des facteurs socio-économiques sont associés à l´acceptabilité du dépistage néonatal de la drépanocytose pendant la COVID-19 à Kisangani, en RDC.

Méthodes

étude observationnelle conduite dans les maternités de Kisangani du 21 mars au 30 juin 2020 chez les mères sensibilisées au dépistage néonatal de la drépanocytose de leurs nouveau-nés à l´hemotypeSC^TM (HT401RUO-USA). Les données recueillies étaient la parité, le niveau d´étude, l´âge, le niveau socio-économique, la profession, la notion de sensibilisation et le motif du refus du dépistage.

Résultats

sur 55,5% (273/492) des mères sensibilisées, 107 (39,19 %) ont accepté et 166 (60,80 %) ont refusé le dépistage néonatal de la drépanocytose chez leur nouveau-né. Les motifs du refus étaient l´absence d´information (67,5%; IC 95% [59,8-74,5]), le manque d´argent dû au confinement (66,3%; IC 95% [58,5-73,4]), la prise de sang pour tentative du vaccin anti-COVID-19 (63,2%; IC 95% = [55,4-70,6]). Les facteurs associés à l´acceptabilité du dépistage étaient l´âge > 35 ans (p = 0,0009; ORa = 3,04; IC 95% = 1,57-5,87) et le bas niveau socio-économique (p = 0,0016; ORa = 2,29; IC à 95% = 1,37-3,85).

Conclusion

l´acceptabilité du dépistage néonatal de la drépanocytose pendant la COVID-19 reste faible à Kisangani. Le gouvernement devrait identifier les canaux de communication efficaces afin de promouvoir les initiatives dans le secteur de la Santé.

Belgian rare diseases plan in clinical pathology: identification of key biochemical diagnostic tests and establishment of reference laboratories and financing conditions

Background

One objective of the Belgian Rare Diseases plan is to improve patients’ management using phenotypic tests and, more specifically, the access to those tests by identifying the biochemical analyses used for rare diseases, developing new financing conditions and establishing reference laboratories.

Methods

A feasibility study was performed from May 2015 until August 2016 in order to select the financeable biochemical analyses, and, among them, those that should be performed by reference laboratories. This selection was based on an inventory of analyses used for rare diseases and a survey addressed to the Belgian laboratories of clinical pathology (investigating the annual analytical costs, volumes, turnaround times and the tests unavailable in Belgium and outsourced abroad). A proposal of financeable analyses, financing modalities, reference laboratories’ scope and budget estimation was developed and submitted to the Belgian healthcare authorities. After its approval in December 2016, the implementation phase took place from January 2017 until December 2019.

Results

In 2019, new reimbursement conditions have been published for 46 analyses and eighteen reference laboratories have been recognized. Collaborations have also been developed with 5 foreign laboratories in order to organize the outsourcing and financing of 9 analyses unavailable in Belgium.

Conclusions

In the context of clinical pathology and rare diseases, this initiative enabled to identify unreimbursed analyses and to meet the most crucial financial needs. It also contributed to improve patients’ management by establishing Belgian reference laboratories and foreign referral laboratories for highly-specific analyses and a permanent surveillance, quality and financing framework for those tests.

Supplementary Information

The online version contains supplementary material available at 10.1186/s13023-021-01728-1.

[Sickle cell disease in the Democratic Republic of the Congo: what are the barriers to treatment using hydroxyurea?]

Introduction

l´hydroxyurée est le seul produit dont l´efficacité a été prouvée pour prévenir les complications de la drépanocytose et approuvé par la « Food and Drug Administration». Pour pouvoir offrir ce traitement aux patients atteints de drépanocytose, il doit être prescrit, disponible et à un prix abordable. L´objectif de cette étude est de déterminer la disponibilité et le coût de l´hydroxyurée sur le marché en République Démocratique du Congo (RDC) et comparer les deux aspects entre une ville reculée, à savoir Mbujimayi, et une grande ville, à savoir, Lubumbashi.

Méthodes

il s´agit d´une étude transversale réalisée dans le cadre d´une enquête face-à-face menée du 1^er avril au 1^er septembre 2017 auprès de 188 pharmacies congolaises.

Résultats

hydroxyurée était disponible dans 41/188 (22%) pharmacies participantes, mais plus fréquemment dans celles d´une grande ville que dans celles d´une ville reculée (34/96 contre 7/92). La plupart des patients ont reçu une ordonnance médicale (36/41; 88%). Le prix moyen de l´hydroxyurée était de 15 $ (10 $ à 35 $) pour une boîte de 25 gélules; ce prix est supérieur au pouvoir d´achat de la majorité des patients drépanocytaires. L´hydroxyurée reste encore un produit importé de l´Europe, des États-Unis ou d´Asie.

Conclusion

l´hydroxyurée est l´un des principaux traitements permettant d´améliorer l´évolution de la maladie chez les patients drépanocytaires. Néanmoins, en République Démocratique du Congo, sa disponibilité pourrait être améliorée, en particulier dans une ville reculée, et son prix reste trop élevé pour être payé par la population locale.

Sickle Cell Disease in the Democratic Republic of Congo: Assessing Physicians' Knowledge and Practices

Background: Sickle cell disease is a major public health issue in the Democratic Republic of Congo (DRC), but it is still poorly understood by health professionals. The objective of this study was to assess the knowledge and practices of Congolese physicians treating sickle cell disease (SCD), in order to identify the areas for improvement in clinical care. Methods: This was a descriptive observational study conducted among Congolese physicians using a questionnaire. Participants were evaluated using a pre-established answer grid. Results: A total of 460 physicians participated, including 81 women (18%), with an average age of 35 years (range 25–60 years). Most physicians were general practitioners. Although self-assessment of their level of knowledge on SCD was estimated as average to good, less than half of the participants (n = 460; 46%) reported adequate management of vaso-occlusive crises, and only 1% of them had received specific training on SCD. Most physicians reported difficulties both in terms of diagnostic (65%) and management (79%) options of SCD patients. This study also showed that 85% of these physicians did not have access to the diagnostic tools for SCD. Conclusions: Insufficient knowledge on SCD and poor diagnostic and treatment options might contribute to increased morbidity and mortality of patients living in the DRC. Interventions aiming to improve physicians’ knowledge, patient follow-up, and treatment access are needed. Specific training alongside existing programs (HIV, malaria), early diagnosis of the disease, and the creation of patient advocacy groups should be implemented to improve SCD patient care.

Detection of a Large Novel α-Thalassemia Deletion in an Autochthonous Belgian Family

α-Thalassemia (α-thal) is a common hemoglobinopathy mainly caused by deletion of one or both α-globin genes. We describe an autochthonous Belgian family diagnosed with α-thal trait. Molecular analysis revealed a novel large deletion of at least 170 kb between 226.68 kb (0.2 Mb) and 402.68 kb (0.4 Mb) from the telomere of 16p, leaving the subtelomeric region intact. The deletion includes both α-globin genes (HBA1 and HBA2) but also flanking genes possibly related to non hematological effects: HBQ1, LUC7L, ITFG3, RGS11, ARHGDIG, PDIA2 and AXIN1. These genes are not contained in the region (0.9 and 1.7 Mb from the telomere of 16p) associated with α-thal intellectual disability (ATR-16) syndrome. However, further research is necessary to exclude other potential effects than α-thal in patients with a large deletion at 0.2-0.4 Mb from the telomere of 16p. Genetic counseling is important for carriers of this deletion as homozygosity for the α-globin (- -/) haplotype may lead to Hb Bart's (γ4) hydrops fetalis syndrome.

Newborn Screening for Sickle Cell Disease in Europe

The history of newborn screening (NBS) for sickle cell disease (SCD) in Europe goes back almost 40 years. However, most European countries have not established it to date. The European screening map is surprisingly heterogenous. The first countries to introduce sickle cell screening on a national scale were France and England. The French West Indies started to screen their newborns for SCD as early as 1983/84. To this day, all countries of the United Kingdom of Great Britain and Northern Ireland have added SCD as a target disease to their NBS programs. The Netherlands, Spain and Malta also have national programs. Belgium screens regionally in the Brussels and Liège regions, Ireland has been running a pilot for many years that has become quasi-official. However, the Belgian and Irish programs are not publicly funded. Italy and Germany have completed several pilot studies but are still in the preparatory phase of national NBS programs for SCD, although both countries have well-established concepts for metabolic and endocrine disorders. This article will give a brief overview of the situation in Europe and put a focus on the programs of the two pioneers of the continent, England and France.

[Awareness and attitudes of 50 congolese families affected by sickle cell disease: a local survey]

Introduction

Sickle cell disease is a very common disease in the Democratic Republic of the Congo, but it is poorly known despite having an impact on the morbi-mortality. Our study aimed to evaluate the extent of awareness and attitudes of families affected by sickle cell disease as well as the impact of this disease in their daily lives.

Methods

We conducted a cross-sectional study of a unique non-random sampling from 50 families affected by sickle cell disease in Mbujimayi, Democratic Republic of the Congo, from 15 June to 15 August 2015. Participants were interviewed using a standardized questionnaire.

Results

This study focuses on 50 families affected by sickle cell disease; medical characteristics were found only in first children affected by sickle cell disease in each household. Less than 10% of families had minimally ill children. Fifty families were interviewed, of whom 22 had more than one child with sickle cell disease. The average age at diagnosis was 1 years. Diagnosis was based on clinical examination in 42% (21) of cases. Each first child affected by sickle cell disease had an average of 3.4 crises per year, 4 episodes of fever per year, received an average of 1.9 transfusions per year and was hospitalized an average of 3 times per year. Thirty-one families (62%) didn't have sufficient monthly income to help their children to manage sickle cell disese, 48 (96%) families hoped that a reference sickle cell centre would be established in Mbujimayi and 47 (94%) would accept to subscribe to health insurance if the annual amount were between $50 and $100.

Conclusion

The extent of awareness among families directly affected by sickle cell disease in Mbujimayi, Democratic Republic of the Congo, is low. This has a direct impact on the management of children with sickle cell disease. The socioeconomic status of these families is also a factor which should be taken into account. The establishement of a reference center and the possibility to fix an annual amount for the treatment of patients would be a strategic approach to implement the awareness and the attitudes of families in relation to this disease having a direct impact on the morbi-mortality of patients.

Comparison of two assays measuring human chorionic gonadotrophin serum concentrations in pregnancy termination and trophoblastic or non-trophoblastic tumours

BACKGROUND

Differences in human chorionic gonadotrophin (hCG) results provided by the commercial immunoassays reflect the heterogeneity of antibodies and the use of suboptimal standards. As a consequence, the principal forms of hCG and metabolites are differentially detected and the hCG tests are not suited for the same clinical applications. Conflicting results are available in the literature regarding which hCG variants are recognized by the Roche Elecsys hCG + β test. The aim of our study was to compare the hCG concentrations provided by the Siemens Immulite 2000 test and the Roche test as well as to assess the concordance between both assays.

METHODS

In this purpose, 152 samples obtained from women and 44 samples from men were analysed by both tests during the follow-up of pregnancy termination, gestational trophoblastic disease and malignancies. The intermediate precision of the Roche test was also investigated on a pool with a low hCG concentration.

RESULTS AND CONCLUSIONS

The hCG concentrations measured with the Roche test were slightly lower compared with the Siemens assay; mean biases of -34.2% and -8% were respectively obtained for hCG values ≤100 UI/L and higher than 100 UI/L. The overall agreement between both assays was 96.1% for women and 97.7% for men. By using an upper reference limit of 3.2 UI/L for women and 1.6 UI/L for men, the Roche test demonstrated a respective concordance of 98.7% and 100%. This test also yielded an excellent precision with a coefficient of variation of 2.8% at a mean hCG concentration of 7 UI/L.

Neonatal screening improves sickle cell disease clinical outcome in Belgium

Objectives

To compare the outcomes of sickle cell disease patients diagnosed through neonatal screening with those who were not.

Methods

In an observational multicenter study in Belgium, 167 screened and 93 unscreened sickle cell disease patients were analyzed for a total of 1116 and 958 patient-years of follow-up, respectively. Both groups were compared with propensity score analysis, with patients matched on three covariates (gender, genotype, and central Africa origin). Bonferroni correction was applied for all comparisons.

Results

Kaplan–Meier estimates of survival without bacteremia were significantly higher in the screened group than the unscreened group (94.47%; [95% CI, 88.64–97.36%] versus 83.78% [95% CI, 72.27–90.42%]), p = 0.032. Non-significant differences between both groups were reported for survival without acute chest syndrome, acute anemia, cerebral complication, severe infection, and vaso-occlusive crisis. Significantly lower hospitalization rate and days per 100 patient-years were observed in the screened compared with the unscreened group (0.27 vs. 0.63 and 1.25 vs. 2.82, p = 0.0006 and <0.0001).

Conclusion

These data confirm the benefit of a neonatal screening programme in reducing bacteremia and hospitalization.

Next-generation osmotic gradient ektacytometry for the diagnosis of hereditary spherocytosis: interlaboratory method validation and experience

Background:

Osmotic gradient ektacytometry is part of the laboratory diagnosis process of hereditary spherocytosis (HS) and other red blood cell (RBC) membrane disorders. We here present the experience of two independent institutions with a next-generation ektacytometer, the LoRRca MaxSis analyzer, in HS diagnostic settings.

Methods:

Inter- and intra-assay variability and sample stability were analyzed. Samples from patients with HS (n=40), probable HS (n=21), auto-immune hemolytic anemia (n=7), and other pathologies (n=37) were studied. Daily controls were run in parallel with patient samples. Results were expressed as percent of change compared to mean of controls.

Results:

Analytical performances showed an inter-assay variability between 0.2% and 3%. Samples were stable for 48–72 h depending of temperature storage and anticoagulant used. The following diagnostic cut-offs were established for HS: an increase of more than 21.5% for the osmolality point at the minimal elongation index (O min), a decrease of more than 8.5% for the maximal elongation index (EI max), and a decreased area under the curve (AUC) of more than 18.5% compared to the mean of controls.

Conclusions:

As the previous instrument, the next-generation ektacytometer is an efficient tool for laboratory diagnosis of HS. Sample stability and standardized reporting of results allow inter-laboratory exchange and comparison. The most useful parameters for HS diagnosis were AUC, EI max, and O min; unfortunately, this method does not differentiate between HS and auto-immune hemolytic anemia (AIHA), but it distinguishes HS from other hereditary membrane pathologies. It can thus be considered as an intermediate step between screening and diagnostic tests.

The place of capillary electrophoresis techniques in screening for haemoglobinopathies

Background: Capillary zone electrophoresis (CZE) methods are new laboratory diagnostic tools. The screening of haemoglobin (Hb) variants by a battery of two automated CZE methods at alkaline and acid pH, followed by micellar electrokinetic capillary chromatography (MECC), has been evaluated.

Methods: Three hundred and ninety-two patients' samples with an abnormal haemoglobin fraction, detected either by isoeletric focusing (IEF) or by automated cation-exchange exchange high-performance liquid chromatography (automated HPLC), were tested by both CZE methods. Their performances were compared with IEF and automated HPLC techniques. The place of MECC has been evaluated.

Results: Using both CZE methods, the clinically relevant variants (HbS, HbC, etc.) as well as 15 of 20 clinically silent variants tested were separated from HbA. Using the alkaline CZE method, a presumptive identification of Hb Bart's, HbH and Hb Constant Spring was obtained. Complementary testing by MECC has demonstrated it to be an aid in distinguishing the globin chain mutations before confirmation by DNA or protein structure analysis.

Conclusion: Using only one device, alkaline CZE, acid CZE and MECC methods offer high resolution, automated sampling and rapid analysis. They are good tools for screening of haemoglobinopathies and can replace conventional techniques.

Neonatal haemoglobinopathy screening: review of a 10-year programme in Brussels

Since 1994, a neonatal screening programme for major haemoglobinopathies has been conducted in Brussels. We performed a 10-year re-evaluation of the incidence of haemoglobinopathies in Brussels and found that of the 118,366 newborns screened, 64 were diagnosed with a sickle cell syndrome, six had β-thalassaemia major, four had a haemoglobin C disease and three had a haemoglobin H disease. Of the 64 babies with a sickle cell disease, two died before the age of two years and two did not present at the first neonatal visit. Of the six babies suffering from β-thalassaemia major, all are alive and two have undergone a haematopoietic stem cell transplantation. The universal neonatal screening programme for haemoglobinopathies should be maintained in Brussels.

Red blood cell disorders in Rwandese neonates: screening for sickle cell disease and glucose-6-phosphate dehydrogenase deficiency

Objectives: To determine the prevalence of haemoglobin (Hb) variants and glucose-6-phosphate dehydrogenase (G6PD) deficiency in Rwanda.

Methods: During a two-month period in 2005, 987 cord blood samples were obtained in two hospitals in Kigali and Butare, Rwanda. Screening for sickle cell disorders, other Hb disorders, G6PD deficiency and other rare erythroenzymopathy deficiencies was done using isoelectric focusing techniques and quantitative kinetic assays, respectively.

Results: The prevalence of Hb S trait was 2.7% and that of G6PD deficiency was 3.8%. No neonate suffered from a sickle cell disease (homozygous for Hb S or compound heterozygous for Hb S), from another clinically significant haemoglobinopathy, or from pyruvate kinase or glucose phosphate isomerase deficiency.

Conclusions: Sickle cell disorders should be considered a public health problem in Kigali and Butare. A systematic neonatal screening programme for those disorders, and to diagnose G6PD deficiency, seems reasonable, but local health priorities must be considered. Adapted management of hereditary sickle cell and G6PD disorders should be available.

Hepcidin on 24-hour urine collection: preanalytical aspects and correlation with ferritin levels

BACKGROUND

Urine hepcidin measurement is a potential non-invasive tool for assessing iron stores. However, hepcidin, due to its amphipathic structure, tends to aggregate and to adhere to surfaces in a protein-poor environment. In this study, we assessed the effect of solid bovine serum albumin (BSA) at different final concentrations (0, 2.5 or 5 g/L) in limiting the loss of hepcidin in spot urine samples. We also explored how hepcidin measured on plasma, spot or 24-hour urine collections can identify iron deficiency.

METHODS

Hepcidin levels were quantified on plasma, spot (with or without BSA) or 24-h urine collections for 33 volunteers. Hematological and iron status parameters were measured for each individual. The ability to detect iron deficiency (defined as a ferritin level <30 μg/L) based on plasma, spot or 24-h urine collections hepcidin levels was assessed by the means of receiver operator curves analysis.

RESULTS

The addition of BSA into urine prior to sample collection prevented hepcidin loss by 13.3% (mean) in spot urine samples whatever the amount. The areas under the receiver operator curves obtained for detecting iron deficiency were respectively 0.94 and 0.93 for hepcidin levels obtained on plasma and 24-h urine collections.

CONCLUSION

In this study, we showed that the addition of solid BSA into urine sample collection containers could prevent aggregation of hepcidin and that 24-h urine hepcidin levels could be as efficient as plasma concentrations for identifying iron deficiency.

Survival among children and adults with sickle cell disease in Belgium: Benefit from hydroxyurea treatment

OBJECTIVE

To evaluate the survival of patients with sickle cell disease (SCD) recorded in the Belgian SCD Registry and to assess the impact of disease-modifying treatments (DMT).

METHOD

The Registry created in 2008 included patients of eight centers. All available data in 2008 were retrospectively encoded in the database. After 2008 and until 2012, all data were recorded prospectively for already registered patients as well as newly diagnosed subjects. Data were registered from neonatal screening or from diagnosis (first contact) until last follow-up or death. Data included diagnosis, demography, and outcome data.

RESULTS

We collected data from 469 patients over a 5,110 patient years (PY) follow-up period. The global mortality rate was low (0.25/100 PY), although 13 patients died (2.8%) and was similar between children, adolescents (10-18 years), and young adults (P = 0.76). Out of the cohort, 185 patients received hydroxyurea at last follow-up (median duration of treatment: 10.3 years), 90 underwent hematopoietic stem cell transplantation (HSCT), 24 were chronically transfused, and 170 had never had any DMT. Hydroxyurea showed significant benefit on patients outcome as reflected by a lower mortality rate compared to transplanted individuals or people without DMT (0.14, 0.36, and 0.38 per 100 PY, respectively) and by higher Kaplan-Meier estimates of 15 year survival (99.4%) compared to HSCT (93.8%; P = 0.01) or no DMT groups (95.4%; P = 0.04).

CONCLUSION

SCD mortality in Belgium is low with no increase observed in young adults. Patients treated with hydroxyurea demonstrate a significant benefit in survival when compared to those without DMT or transplanted.

[Newborn screening : the point of view of the paediatrician]

Newborn screening is a public health effort that has changed the prognosis of some congenital diseases. Newborn screening programmes differ between countries in which it is organized. Demographic, epidemiological or economic factors play a role in the choice of the screening panel. In the French Community of Belgium, the programme focuses on 13 metabolic and endocrine diseases, hearing loss and hemoglobinopathies (Brussels and Liege). Newborn screening is a complex process that requires the involvement of all stakeholders : parent information, blood sampling or testing, lab analysis, follow-up of the results, initiate adequate care in case of positive test and genetic counselling. Newborn screening programmes will evolve in the next years. New therapeutic and diagnostic methods will make other genetic diseases candidates for screening. Whole genome sequencing may be the next expansion; it will create new opportunities but will pose new ethical dilemmas. We must all prepare now for future challenges.

Study of FibroTest and hyaluronic acid biological variation in healthy volunteers and comparison of serum hyaluronic acid biological variation between chronic liver diseases of different etiology and fibrotic stage using confidence intervals

OBJECTIVES

Personalized ranges of liver fibrosis serum biomarkers such as FibroTest or hyaluronic acid could be used for early detection of fibrotic changes in patients with progressive chronic liver disease. Our aim was to generate reliable biological variation estimates for these two biomarkers with confidence intervals for within-subject biological variation and reference change value.

DESIGN AND METHODS

Nine fasting healthy volunteers and 66 chronic liver disease patients were included. Biological variation estimates were calculated for FibroTest in healthy volunteers, and for hyaluronic acid in healthy volunteers and chronic liver disease patients stratified by etiology and liver fibrosis stage.

RESULTS

In healthy volunteers, within-subject biological coefficient of variation (with 95% confidence intervals) and index of individuality were 20% (16%-28%) and 0.6 for FibroTest and 34% (27%-47%) and 0.79 for hyaluronic acid, respectively. Overall hyaluronic acid within-subject biological coefficient of variation was similar among non-alcoholic fatty liver disease and chronic hepatitis C with 41% (34%-52%) and 45% (39%-55%), respectively, in contrast to chronic hepatitis B with 170% (140%-215%). Hyaluronic acid within-subject biological coefficients of variation were similar between F0-F1, F2 and F3 liver fibrosis stages in non-alcoholic fatty liver disease with 34% (25%-49%), 41% (31%-59%) and 34% (23%-62%), respectively, and in chronic hepatitis C with 34% (27%-47%), 33% (26%-45%) and 38% (27%-65%), respectively. However, corresponding hyaluronic acid indexes of individuality were lower in the higher fibrosis stages.

CONCLUSION

Non-overlapping confidence intervals of biological variation estimates allowed us to detect significant differences regarding hyaluronic acid biological variation between chronic liver disease subgroups.

e-ENERCA: Telemedicine Platform for Rare Anaemias

The creation of a telemedicine, tele-expertise platform opens a new challenge within the European Network for Rare and Congenital Anaemias (ENERCA; www.enerca.org). This is a cornerstone in the field of rare anaemias, in which national expertise is usually scarce and a significant number of patients remain undiagnosed. Experts in rare diseases are specially needed of shared knowledge platforms offering the possibility of a faster and more accurate diagnosis and the availability of a better patients’ follow-up. The platform developed by e- ENERCA will be user friendly and intuitive so it will be used by the majority of professionals without requiring a specific formation. The idea of inter professional consultation is to bring medical experts together for collaborative involvement in activities that maximize the benefits and improvement in patient care.

Recommendations for Centres of Expertise in Rare Anaemias. The ENERCA White Book

The Community added value of Centres of Expertise (CoE) and European Reference Networks (ERN) is particularly high for rare diseases (RD) due to the rarity of these conditions, which implies both a small number of patients and scarcity of expertise within a single country. Gathering expertise at the European level is therefore, paramount in order to ensure equal access to accurate information, appropriate and timely diagnosis and high quality clinical care and follow up for patients with rare diseases. This applies particularly to rare anaemias due to the high number of different rare diseases that constitute this group. In this context, the European Network for Rare and Congenital Anaemias (ENERCA), co-financed by the European Commission, was created in 2002 with the aim of prevention and management of rare anaemias (RA) and the development and promotion of policies to improve the well-being of European Union citizens. The ENERCA White Book is a position paper, developed as a deliverable of the ENERCA (phase 3) project that intends to contribute to the creation of a ERN in RA (ERN-RA) by preparation of the recommendations and, in particular, the definition of the criteria that CoE, local centres (LC) and their interrelations have to fulfil as healthcare providers. It has been nourished by all the activities that have been performed over the past ten years within the ENERCA framework. The White Book is addressed to authorities in charge of the identifying CoE, as an essential requirement for the official recognition of the ERN, to European and national health authorities, Healthcare centres and health professionals, as well as to all other stakeholders interested in RA. It is also addressed to the patients, as a way to empower their community in this process. One particular characteristic of the White Book is the integration of the three main aspects of a CoE: (a) ethical and legal frameworks to ensure the non-discrimination and non-stigmatisation of rare disease patients across Europe, within their sphere of competencies; (b) clinical and laboratory frameworks for defining technical and quality criteria including scope, general and disease specific elements currently defined as technical and professional standards for the diagnosis, treatment and follow-up of patients with RA; and (c) the expectations patients have of CoE. Conceived as a working tool directed to a broad range of stakeholders, the White book has been designed and structured to be comprehensible even to non-technical and /or non-professional audiences. The reader will find an up-to-date description and epidemiological information on RA as well as the European Union background policies for defining CoE and ERN-RA. A working group was created with experts of different profiles, known as the European Working Group on Rare Anaemias (EGRA). In order to achieve its objectives, the methodology used by EGRA, was characterised by three main principles: Interdisciplinary, European coverage, and evidence-based principles. Work has been developed into four sequential steps: 1. Analysis of the current situation of RA in Europe by healthcare professionals in order to identify the most relevant issues that have to be addressed by a centre in order for it to be recommended as CoE. 2. Preparation of questionnaires to perform surveys on how the relevant issues identified in step 1 can be translated into practical recommendations. 3. Analysis of the questionnaire results by face to face meetings, feedback and consensus evaluation, and 4. Preparation of a report on ENERCA policy recommendations for CoE. This report is presented in a user-friendly format, easy to understand and available through the ENERCA website (www.enerca.org). Several important conclusions can be drawn from the ENERCA White Book, including the importance of laboratories involved in the diagnosis of RA, patient oriented and multidisciplinary care at the CoE, the need for coordination and cooperation within and outside the centre, the provision of information to patients and health professionals and the involvement of public authorities at the national and European levels. Official recognition of this structure and assurance of its long term sustainability will only be achieved if public authorities work hand by hand with both professionals experts in different disciplines and patients. Finally, the ENERCA White book aims to be a practical tool for health authorities of Member States (MS) that are preparing their national directory of formally designated CoE. For this, it is important that MS authorities recognise RA as an important health component to be included within the National Plans or Actions for Rare Diseases.

[Anemia in the elderly]

Anaemia is a problem that affects almost 10% over 65 years and 20% over 85 years. There is no physiological anaemia in the elderly. Any anaemia expresses the existence of a pathological process, regardless of its severity. Anaemia in the elderly is always associated with a poor prognosis that is in terms of mortality, morbidity and risk of fragility. The diagnostic approach to anemia in the elderly is the same as in younger individual. There are many causes of anaemia; anaemia balance is a complex diagnostic process. Most anaemias are due to a deficiency, chronic inflammation or comorbidity. However, in the elderly, the etiology of anaemia is often multifactorial. In a number of cases remain unexplained anaemia. In a number of cases, anemia remain unexplained. Treatment of anaemia is the treatment of the cause, but specific therapeutic aspects to the elderly should be considered, as among other martial substitution or use of erythropoietin (EPO).

Serum and red blood cell folate testing for folate deficiency: new features?

INTRODUCTION

Folate deficiency is assessed by serum and red blood cell folate measurements. Nevertheless, no consensus for the lower limit of serum folate reference values exists. We investigated the appropriate use of RBC folate to detect folate deficiency and the relationship between serum and RBC folate and with other parameters such as vitamin B12 and homocysteine in order to propose serum folate cut-off values.

METHODS

Retrospectively, 63,113 and 20,459 results of serum and RBC folate were collected. If present, the results of red cell indices, vitamin B12 and homocysteine were also collected.

RESULTS

A significantly positive correlation between serum and RBC folate was demonstrated. A significant effect of serum folate levels under 6 μg/L (or 14 nm) was observed on RBC indices. A relation was found between vitamin B12 and folate, for serum and RBC. A significant rise in homocysteine concentrations was observed for serum folate levels under 8 μg/L (or 18 nm).

CONCLUSION

To observe haematological abnormalities, folate deficiency should be profound. Serum folate levels under 8 μg/L (or 18 nm) should be considered as a decision limit for folate depletion because a positive effect on homocysteine was observed. Fasting serum folate concentration should be preferred for assessing folate status. Our results suggest that the need for RBC folate testing is less meaningful.

[Sickle cell anemia and transfusion safety in Bamako, Mali. Seroprevalence of HIV, HBV and HCV infections and alloimmunization belonged to Rh and Kell systems in sickle cell anemia patients]

Red cell transfusion is one of the main treatments in sickle cell disease. However there are potential risks of blood transfusions. In order to propose strategies to improve blood safety in sickle cell disease in Mali, we conducted a prospective study of 133 patients with sickle cell anemia recruited at the sickle cell disease research and control center of Bamako, November 2010 to October 2011. The study aimed to determine the prevalence of human immunodeficiency virus (HIV), hepatitis B virus (HBV), and hepatitis C virus (HCV) infections by serum screening and the frequency of red cell alloimmunization before and after blood transfusion. The diagnosis of sickle cell syndrome was made by HPLC, the detection of markers of viral infection was performed by ELISA, and the diagnosis of alloimmunization was conducted by the Indirect Coombs test. Prevalence of viral infections observed at the time of enrolment of patients in the study was 1%, 3% and 1% respectively for HIV, HBV and HCV. Three cases of seroconversion after blood transfusion were detected, including one for HIV, one for HBV and one another for HCV in sickle cell anemia patients. All these patients had received blood from occasional donors. The red cell alloimmunization was observed in 4.4% of patients. All antibodies belonged to Rh system only. Blood transfusion safety in sickle cell anemia patients in Mali should be improved by the introduction of at least the technique for detecting the viral genome in the panel of screening tests and a policy of transfusions of blood units only from regular blood donors.

Time course of iron metabolism in critically ill patients

BACKGROUND

Altered iron metabolism plays a central role in the development of anaemia in critically ill patients but the time course of iron status in septic and non-septic critically ill patients has not been well defined.

METHODS

Prospective study in a 34-bed medico-surgical ICU. The complete blood count, iron, ferritin, transferrin, and transferrin receptor concentrations, transferrin saturation and C-reactive protein (CRP) concentrations were measured on days 1, 3 and 5 of the ICU stay in 95 consecutive ICU patients (33 with sepsis and 62 without).

RESULTS

Despite an identical complete blood count on day 1, septic patients had significantly lower iron concentrations (21 [13-34] vs 50[28-75] microg/dL, p<0.001), transferrin concentrations (169[121-215] vs 214[173-247] mg/dL; p=0.003), and transferrin saturation (11[7-15] vs 19[11-25]%; p= 0.004), and higher ferritin concentrations (432[184-773] vs 204[78-354] ng/mL; p=0.002) than non-septic patients. These alterations were associated with a lower reticulocyte count (42[29-61] vs 58[48-77] x 10(3)/mm3; p=0.028). On day 1, CRP concentrations, which were higher in septic than in non-septic patients (20.0[13.5-27.5] vs 2.3[0.7-5.9] mg/dL; p<0.001), were directly correlated with ferritin concentrations (rho=0.55, p<0.001) and inversely correlated with transferrin concentrations (rho=-0.49, p=0.0001) and transferrin saturation (rho=-0.49, p=0.0001). After 3 days, iron and transferrin concentrations were identical in septic and non-septic patients. Iron metabolism remained altered in both populations until the 5th day.

CONCLUSIONS

Iron status is rapidly altered in critically ill patients, especially in septic patients. These alterations persist during the course of the disease and are associated with decreased erythropoiesis.

Automated capillary electrophoresis in the screening for hemoglobinopathies

Hemoglobinopathies are genetic disorders of globin chains characterized by the decreased expression of α- or β-globin chains (thalassemias) or by the synthesis of an abnormal protein (hemoglobin variants in, e.g., sickle cell disease). The screening of most hemoglobinopathies relies, together with hematological results and clinical elements, on the separation and quantification of normal and abnormal hemoglobin fractions. Gel electrophoresis, isoelectric focusing, and HPLC have been the methods of choice for many years. For about 20 years, capillary electrophoresis has appeared as a strong alternative method. Since the early 2000s, automated instruments are commercially available for the analysis of Hb fractions in adult patients but also for neonatal screening.

Separation of hemoglobin variants by capillary electrophoresis

Quantitative defects in hemoglobin (Hb) are represented by Hb variants, where the amino acids sequence is modified as a consequence of a mutation in the α or β-globin genes. More than 1,100 variants have been described so far but only a few dozen are clinically significant; the most significant being Hb S, which in the homozygous state causes sickle cell disease. The majority of the methods used to detect Hb variants are based on the charge difference of the mutated globin chain. We have developed a micellar capillary electrophoresis (MEKC) method using highly acidic conditions and a high Triton(®) concentration. Separation times in the order of 20 min were able to resolve all normal and 29 abnormal globin chains including Hb E. This method was initially developed for Beckman P/ACE 5500 Instrument but has been modified for the more recent P/ACE MDQ and PA 800 instruments; however, the method can be adapted to any kind of CE analyzer.

Screening for haemoglobinopathies on cord blood: laboratory and clinical experience

Objectives

Blood from the umbilical cord (cord blood) is screened for haemoglobinopathies in several neonatal screening programmes, as well as before banking as a source of stem cells. We investigated the pre-analytical and analytical aspects of neonatal screening for haemoglobinopathies on liquid cord blood using the Sebia Haemoglobin kit. We give an interpretation of the results as well as a proposed scheme for reporting of the results.

Methods

A neonatal screening programme on liquid cord blood has been performed in all labour wards in Brussels since 1994. Using that material, the screening methods of isoelectric focusing and capillary zone electrophoresis were compared using 962 cord blood samples. From December 2008 to December 2010, 47,388 neonatal samples were analysed by capillary electrophoresis as the first-line method for neonatal screening. High-performance liquid chromatography was used as the second-line method.

Results

Capillary zone electrophoresis on liquid cord blood enabled the detection of all clinically significant haemoglobin variants, significant levels of Hb Bart's, and β-thalassaemia major. Among the 47,388 neonatal samples tested, 362 (0.7%) were suspected to be contaminated with maternal blood, but no diagnostic error was reported retrospectively for a major haemoglobinopathy. Recommendations for the interpretation and reporting of results of neonatal screening for haemoglobinopathies using the Sebia Haemoglobin kit are proposed.

Conclusions

A routine capillary electrophoresis kit adapted to neonatal screening and liquid cord blood is reliable for screening for haemoglobinopathies. It enables early detection and reporting of all major haemoglobinopathies and most minor ones. It also enables use of a simple scheme to report the results.

Rapid quantification of six β-lactams to optimize dosage regimens in severely septic patients

A fast analytical procedure was developed for the simultaneous quantification of cefepime (CEF), meropenem (MEM), ceftazidime (CZA), cefuroxime (CFX), aztreonam (AZT), and piperacillin (PIP) in serum of intensive care patients. The β-lactam pharmacokinetic parameters can be altered in severe sepsis due to changes in the distribution, the metabolism and the elimination process. Therapeutic drug monitoring (TDM) of β-lactams is therefore recommended in critically ill patients. The plasma samples were spiked with cefoperazone as internal standard and proteins were precipitated with methanol. The different β-lactams were separated with high performance liquid chromatography within 18 min, and quantified by UV spectrophotometry with a diode array detector. The method was validated by means of the accuracy profile approach based on β expectation tolerance intervals. The acceptance limits were settled at ± 30% according to the regulatory requirements. Assay validation demonstrated good performance for all β-lactams analyzed in terms of trueness, repeatability, linearity and intermediate precision over the range of 2-200 μg/mL. The simple extraction procedure provides respective absolute and relative recoveries ranging from 70% to 86% and from 66% to 89% for all the β-lactams analyzed. Few interferences were observed and the method was easily applicable to TDM in intensive care patients. The quantification of β-lactams should allow for antibiotic regimen adjustment in critically ill patients.

Interlaboratory comparison of current high-performance methods for HbA2

INTRODUCTION

Few data are available on the alignment of the different methods used for HbA(2) quantitation and recent external quality survey results show a consistent spread of HbA(2) values. To this aim, a comparison study among the actual best performing techniques for HbA(2) determination, comprising HPLC and CE methods, was performed.

METHODS

A total of 80 blood samples collected from normal subjects and β-thalassemia carriers were analyzed by different HPLC (Bio-Rad Variant I, Bio-Rad Variant II, Menarini HA-8160, Tosoh G7, Tosoh G8) and capillary electrophoresis (Beckman Coulter MDQ and ProteomeLab PA 800, Sebia Capillarys 2) methods. Patient's samples with clinically relevant hemoglobin variants (HbC, HbD, HbE, HbS, and δ-chain variants) were also tested by all methods.

RESULTS

The mean within-run imprecision of HbA(2) measurement (expressed as CV, %) was between 0.5% and 4.4% (HPLC) and between 1.2% and 4.4% (capillary electrophoresis). The comparison study showed that the different methods were highly correlated (r between 0.974 and 0.997) although biased each other. HbA(2) determination in presence of abnormal hemoglobins was variously interfered by both HPLC and CE methods. Concerning HbF, the mean imprecision at HbF values ≥1.5% was between 1.2% and 8.2% (as CVs).

CONCLUSIONS

A poor alignment of routine methods for HbA(2) measurement was found. The need of a better standardization of HbA(2) measurement procedures was underlined.

Early NT-proBNP is able to predict spontaneous closure of patent ductus arteriosus in preterm neonates, but not the need of its treatment

The objective of this study was to establish the potential utility of N-terminal pro-brain natriuretic peptide (NT-proBNP) in the management of patent ductus arteriosus (PDA). This was a monocentric prospective blind study that was conducted in a referral neonatal intensive care unit. The patients were very low-birth-weight/gestational-age neonates. Babies with cardiac congenital anomaly other than PDA, life-threatening congenital malformation, severe asphyxia at birth, persistent pulmonary hypertension, and death within the first week of life were excluded. Plasma NT-proBNP concentrations were determined on days 2, 4, and 7 of life. Echocardiography was performed on days 4 and 7. Results were blinded to clinicians. Only echographic results were available upon request. Thirty-one infants were included. NT-proBNP levels were significantly correlated to ductal size and to left atrial-to-aortic diameter ratio. The median NT-proBNP on both days 2 and 4 was significantly higher in neonates with later treated or persistent PDA. A level above 10.000 pg/mL at 48 h of age yielded a 100% positive and a 87% negative predictive value to exclude spontaneous ductal closure. However, no NT-proBNP threshold could predict which PDA would be judged necessary to treat. It was concluded that early low NT-proBNP values can be used as a reliable independent marker to predict spontaneous ductal closure in preterm neonates. Yet, high NT-proBNP levels should not be used to guide the decision to treat PDA, the risk being of treating many bystanding PDAs.

[Qualitative analysis of the offer for prevention and caring of sickle cell anaemia in Brussels]

Sickle cell disease (SCD) is the first genetic disease in the world and remains largely ignored by the population but also by health professionals. SCD is characterized by a variable clinical expression, however most of the patients are at risk to develop acute and severe complications conducting to a fatal issue. This study develops a qualitative approach to analyze the adequacy between the services offered for those patients in Brussels and the sociocultural characteristics of the target population and more specifically of the migrant population originating of sub-saharan Africa which is the most concerned. To have a global vision of the preventive and care services provided for SCD in Brussels, semistructured interviews were conducted with health professionals and patients associations. The results were analyzed to determine if they match the expectations of health professionals and audiences across the voluntary sector. The results show the absence of a real recognition at the national level of sickle cell anaemia, a deficit in psychosocial care of patients and their families. SCD is often considered by the African community as a disease of the curse which has to be hidden. To the physical pain and multiple organ complications one must add a psychological distress that patients drive back into silence. The management of this disease therefore requires a dedicated approach. With the exception of newborn screening performed in all maternity hospitals in Brussels and Liège, there is no specific measure for the management of SCD in Belgium.

Erythrocyte membrane protein analysis by sodium dodecyl sulphate-capillary gel electrophoresis in the diagnosis of hereditary spherocytosis

BACKGROUND

Sodium dodecyl sulphate polyacrylamide gel electrophoresis (SDS-PAGE) is currently the reference method for detecting protein deficiencies related to hereditary spherocytosis. The aim of the study was to evaluate an automated capillary gel electrophoresis system, the Experion instrument from BioRad, for its ability to separate and quantify the erythrocyte membrane proteins.

METHODS

The major erythrocyte membrane proteins (actin, protein 4.2, protein 4.1, band 3, ankyrin, α- and β-spectrin) were extracted and purified from membrane ghosts by centrifugation, immunoprecipitation and electroelution. Analyses were performed using SDS-PAGE and sodium dodecyl sulphate capillary gel electrophoresis (SDS-CGE) to establish a separation profile of the total ghosts. Then, the samples from patients received for investigations of erythrocyte membrane defects were analysed.

RESULTS

Five of the seven expected erythrocyte membrane proteins were finally separated and identified. In the 20 studied cases, taking into account the screening test results and the clinical and family histories, the SDS-CGE method allowed us to achieve the same conclusion as with SDS-PAGE, except for the patient with elliptocytosis.

CONCLUSIONS

The new SDS-CGE method presents interesting features that could make this instrument a powerful diagnostic tool for detection of erythrocyte membrane protein abnormalities, and can be proposed as an automated alternative method to the labour intensive SDS-PAGE analysis.

Sickle cell disease from Africa to Belgium, from neonatal screening to clinical management

AIM

To describe the severity of sickle cell disease (SCD) in newborns in Belgium and evaluate the impact of neonatal screening (NS) on clinical outcome.

METHODS

Universal NS of umbilical cord blood for hemoglobinopathy was progressively deployed in Brussels and Liège starting in 1994. No particular population was targeted. Samples were analyzed initially using the isoelectric focusing technique and since 2008 the capillary electrophoresis technique. If a hemoglobin variant was suspected, further analysis was carried out using high performance liquid chromatography. Children presenting major hemoglobinopathy, especially SCD, were referred to a specialized centre for comprehensive management. Preventive measures included antipneumococcal prophylaxis immunization/antibiotic therapy, parental training to recognize severe anemia and splenic sequestration, and transcranial ultrasound recording for early detection of intracranial stenosis. A database was set up in Belgium to collect clinical and laboratory data including parental phenotype, diagnostic technique (neonatal screening or not), major clinical events (episodes of dactylitis, acute chest syndrome, severe anemia, infection, etc), number and duration of required hospitalizations, and treatment used.

RESULTS

Screening of 222352 newborns in maternity units in Brussels led to diagnosis of SCD in 145 patients, Adequate data for analysis of clinical outcome was available for 96 of these children born before 2007. Median age in the study group was 4.2 years and the total duration of follow-up was 510 years. Most cases occurred in families from the Democratic Republic of Congo. (64/96 patients; 66.7%) and involved homozygous hemoglobin S disease (80/96 patients; 83.3%). Twenty-seven percent of patients (26/96) presented no severe clinical events during the study (17 SS, median age 2,1 years (0-13.1 years). Conversely 33% presented an episode of dactylitis and 47.9% (46/96) presented recurrent vasoocclusive crises. Severe anemia was observed in 39.6% (38/96) of cases. Six patients (6.3%) developed septicemia despite prophylactic antibiotic therapy and anti-pneumococcal immunization using heptavalent conjugate vaccine and polysaccharide vaccine, No penicillin-resistant strains were observed. The incidence of stroke was 2.1% (3/96). Two patients presenting homozygous hemoglobin S disease died due to septicemia due to non-compliance with antibiotic therapy in one case and severe anemia in one case. All episodes of septicemia and both deaths occurred at the beginning of the NS program. Hydroxyurea therapy was used in 30 patients (31.2%) including 7 in whom transcranial Doppler depicted blood flow abnormalities and 8 in whom allogeneic bone marrow transplantation was performed.

CONCLUSIONS

Sickle cell disease is still associated with high morbidity and mortality but clinical care has improved and no death has occurred in the last 10 years. NS is an effective tool for early detection and management of SCD. Neonates with SCD diagnosed by NS in Belgium presented severe manifestations, but clinical outcomes were improved by comprehensive management.

Reliability of mycophenolic acid monitoring by an enzyme multiplied immunoassay technique

BACKGROUND

For mycophenolic acid (MPA), substantial inter- and intra-individual variability and drug interactions have been observed and therapeutic drug monitoring is now recommended. In this study, a MPA commercial Enzyme Multiplied Immunoassay Technique (EMIT) was evaluated and compared with the HPLC-UV reference method which is easily practicable in a routine laboratory.

METHODS

Plasma samples (n = 117) were collected from adult renal graft patients treated by mycophenolate in combination with either cyclosporin A (CyA) (n = 32) or tacrolimus (n = 85).

RESULTS

Considering all samples, correlation was excellent (p < 0.0001). However, significant MPA overestimation was observed with EMIT in the early post-transplant period (30%, n = 32) or when combined with cyclosporin (45%).

CONCLUSIONS

In the early post-transplant period, or in cases where CyA is used in combination with MPA, the EMIT cannot be recommended. HPLC or LC/MS are here the method of choice.

Neonatal hemochromatosis and Martinez-Frias syndrome of intestinal atresia and diabetes mellitus in a consanguineous newborn

Neonatal hemochromatosis is a heterogeneous disorder of iron metabolism characterized by hepatic failure and marked iron accumulation in liver and extrahepatic tissues. Autosomal recessive transmission is found in most cases. Neonatal hemochromatosis shares cellular features with the adult disease but is clinically and genetically distinct, the causal gene(s) being presently unknown. We report on a newborn from consanguineous parents who presented with multiple congenital anomalies and neonatal hemochromatosis. The syndrome consisted of intra-uterine growth retardation, intestinal atresia, gallbladder aplasia and diabetes mellitus, and fitted with the diagnosis of Martinez-Frias syndrome, a very rare autosomal recessive phenotype, the gene of which remains to be identified. We suggest that neonatal hemochromatosis may be part of the Martinez-Frias syndrome. Molecular analyses in this and other reported patients with the Martinez-Frias syndrome should shed light on gut development and iron metabolism.

Prevalence of sickle cell disease in a northeastern region of the Democratic Republic of Congo: what impact on transfusion policy?

Transfusion therapy may save the lives of patients with sickle cell disease (SCD), but it is also associated with a high risk of transmission of infection. The aims of this study were to determine the prevalence of SCD in a northeastern region of the Democratic Republic of Congo (DRC), and to define ways in which the procedures involved in the security of transfusions should be improved. During a 3-month period in 2006/2007, 520 samples of umbilical cord blood were obtained through neonatal screening in five health centres in Kisangani. The samples were analysed using an isoelectric focusing technique. The estimated prevalence of sickle cell trait and SCD in the population tested was 23.3 and 0.96%, respectively. These numbers will be presented for the attention of the health authorities in DRC with responsibility for SCD and they will be asked to consider improvements in treatment procedures for SCD, such as blood transfusions, as a public health priority.

[Major alpha-thalassemia: antenatal diagnosis, case report and literature review]

Homozygous alpha-thalassaemia or Bart's hydrops fetalis is a genetic disease with autosomal recessive transmission. The condition is lethal for the fetus because of hypoxia and anemia. For the mother there is an increased risk of the severe forms of preeclampsia and its complications. The diagnosis can be suspected in presence of suggestive ultrasonographic anomalies, where both parents come from South-East Asia or China. Confirmation is based on the identification of the typical deletions or mutation of the alpha globin gene by molecular genetics. We report a rare clinical case of Bart's hydrops fetalis diagnosed because of fetal growth retardation, fetal cardiomegaly and increased size of placenta on the 26 weeks fetal echography. This case underscores the need to include the alpha thalassemias in medical and midwifery education in countries where they were almost inexistent a generation ago.