[Targeted newborn screening for sickle-cell anemia: Sickling test (Emmel test) boundaries in the prenatal assessment in West African area]. / Dépistage néonatal ciblé de la drépanocytose : limites du test de falciformation (test d'Emmel) dans le bilan prénatal en zone ouest africaine.

BACKGROUND: Newborn screening for sickle cell anemia is necessary in Africa where the disease is more frequent. Hemoglobin electrophoresis is used for screening, but is limited by a high cost and difficult access. Sickling test (Emmel test), which is more affordable and technically more accessible, is often requested for prenatal assessment of pregnant women in West African areas to reserve screening for newborns from mothers in whom the positive sickling test attests the presence of hemoglobin S. This study aims to evaluate the number of undetected sickle cell anemia newborns by a screening policy targeting only newborns from mothers in whom a sickling test would have been positive. METHODS: From 2010 to 2012, in Bamako, Mali, West Africa, 2489 newborns were routinely screened for sickle cell anemia at the umbilical cord or heel by isoelectrofocusing and, if necessary, by high-performance liquid chromatography. These newborns were born from 2420 mothers whose hemoglobin was studied by isoelectrofocusing. The data was recorded and processed using Excel software version 14.0.0. We calculated the frequency of the sickle cell gene in mothers and newborns as well as the number of SCA newborns from heterozygous or C homozygous mothers. RESULTS: Of the 2489 newborns, 16 had sickle cell anemia (6 SS and 10 SC); 198 had the sickle cell trait; 139 were AC and 1 was CC. Of the 10 newborns with SC profile, 3 were born from mothers not carrying the S gene but the C gene of hemoglobin and in which an Emmel test would have been negative. CONCLUSION: Targeted newborn screening, based on the results of sickling test in pregnant women, would misdiagnose more than one of six sickle cell anemia newborns who would not benefit from early care. Cost-effectiveness studies of routine newborn screening for sickle cell anemia should lead to a better screening strategy in contexts where hemoglobin S and other hemoglobin defect genes coexist.

[Prevalence and risk factors for sickle retinopathy in a sub-Saharan comprehensive Sickle Cell Center]. / Prévalence et facteurs de risque de la rétinopathie drépanocytaire dans un centre de suivi drépanocytaire d'Afrique subsaharienne.

INTRODUCTION: Retinopathy is a chronic complication with severe functional consequences in patients with sickle cell disease. Its prevalence is not well known in sub-Saharan Africa because of the absence of screening. We report here the results of a routine screening for sickle retinopathy in a Comprehensive Sickle Cell Center in Sub-Saharan Africa. METHODS: Screening of sickle retinopathy was carried out in all sickle cell patients aged 10 and over, followed between 2010 and 2012. Retinopathy was screened by dilated indirect fundoscopic examination and retinal angiography, if necessary. The gender, age and hematological parameters of patients with sickle retinopathy were compared with those of controls randomly selected from the cohort of sickle cell patients without retinopathy followed during the same period. RESULTS: The overall prevalence of sickle cell retinopathy was 8.8% (142/1604): 12.4% (91/731) in SC, 5.2% (38/734) in SS, 9.4% (5/53) in Sß°-thalassemia patients and 9.3% (8/86) in Sß+-thalassemia patients. Proliferative retinopathy was more common in SC patients (P<0.01). High levels of hemoglobin or of hematocrit were associated with retinopathy in all patients and with proliferative retinopathy in SC patients. In SS or Sß0thalassemia patients, high leukocyte count was associated with proliferative retinopathy. Low fetal hemoglobin level was associated with retinopathy in all groups. CONCLUSION: The prevalence of sickle cell retinopathy is high and negatively associated to the level of fetal hemoglobin. The efficiency of a routine screening for sickle cell retinopathy must be assessed in Africa as well as the benefit of phlebotomy and hydroxyurea therapy as a preventive treatments.

Cas rare de leucémie primitive à plasmocytes au Mali

La leucémie primitive à plasmocytes est une pathologie agressive rare, caractérisée par une plasmocytose sanguine supérieure à 20% des leucocytes circulants. C'est une entité clinique proche du myélome multiple dans sa présentation clinique et biologique. Il n'y a pas de schéma thérapeutique bien codifié, mais des cas de rémission complète sont rapportés sous chimiothérapies spécifiques du myélome. Dans ce travail, nous rapportons le cas d'une leucémie primitive à plasmocytes agressive de diagnostic tardif chez un homme de 42 ans, d'origine malienne. La symptomatologie inaugurale était faite d'une bicytopénie expressive avec blastose circulante. Le caractère atypique des cellules et les difficultés techniques n'ont pas permis de poser rapidement le diagnostic, qui fût retenu à l'issue de l'immuno-phénotypage cellulaire réalisée en France. Les cellules exprimaient le CD38, mais étaient négatives pour le CD45, le CD56 et le CD138. Aucune chimiothérapie spécifique n'a pu être initiée devant l'évolution rapide vers le décès 5 mois après le premier contact avec notre service. Ce cas clinique rare incite à améliorer le plateau technique par l'introduction de la cytométrie en flux dans le diagnostic des hémopathies malignes en général, celui des leucémies aiguës atypiques en particuliers. A cause de son pronostic péjoratif en l'absence de thérapeutique précoce, la leucémie à plasmocytes doit être évoquée devant toute blastose sanguine atypique associées ou non à une symptomatologie clinique évocatrice du myélome multiple

[Screening of cerebral vasculopathy in sickle cell anemia children using transcranial Doppler]. / Dépistage de la vasculopathie cérébrale drépanocytaire par doppler transcrânien au Mali.

Cerebral vasculopathy exposes patients to a high risk of stroke, a major complication of sickle cell disease (SCD) associated with a high risk of death and disability. Transcranial doppler (TCD) ultrasonography used to identify SCD patients at risk of stroke may contribute to significantly reducing morbidity and mortality in these patients by indicating appropriate treatment. From March 2008 to February 2013, we conducted systematic screening for cerebral vasculopathy using TCD in 572 SCD patients (including 375 SS, 144 SC, 26 S/ß(0), and 27 S/ß(+) thalassemia patients) aged 1-17 years in a comprehensive center for follow-up and research on sickle cell disease in Bamako, Mali. After exclusion of 30 inadequate results and one case of abnormal TCD observed in a multiple organ failure patient, we found an abnormal or conditional TCD in 18% of 541 children examined in a steady state. The highest prevalence of abnormal cases concerned homozygous SS patients (8.1%). No case of abnormal or conditional TCD was observed in children with S/ß(+) thalassemia. Hemoglobin concentrations were significantly lower in patients with conditional or abnormal TCD (P<0.01). In a subgroup of 68 patients with conditional TCD, nine (13%) converted to abnormal TCD over 1 year. In this subgroup of 68 conditional TCD patients, a decrease or increase in baseline hemoglobin concentration was predictive of conditional or abnormal TCD at the follow-up visit. Progression towards conditional TCD was observed in four patients (0.9%) who initially had normal TCD. Children with abnormal TCD had, whenever possible, a monthly exchange transfusion program. One case of transient stroke in the context of P. falciparum malaria with low hemoglobin concentration and one death were observed. These findings highlight the need for systematic TCD in sickle cell disease monitoring and implementing regular blood transfusion programs in the context of limited access to regular and secure blood transfusions.

[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]. / Sécurité transfusionnelle et drépanocytose à Bamako, Mali. Séroprévalence des infections à VIH, VHB, VHC et allo-immunisation anti-Rh et Kell chez les drépanocytaires.

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.

A metastatic case of gastrointestinal stromal tumor (GIST) treated with imatinib mesylate (Glivec(®)) in Mali.

Gastrointestinal stromal tumors (GIST) usually showing a spindle cells pattern of cell proliferation have recently benefit from a molecular definition. Indeed imatinib mesylate (Gleevec(®)) treatment has dramatically improved the management of these tumors as they frequently express the c-kit oncogene. We report the first case of a metastatic gastric GIST in a man of 45 years diagnosed and treated in Mali. The gastric tumor was particularly aggressive with a large intra-abdominal and mesenteric spreading and liver metastases. The diagnosis was done on the CD117 and CD34 expression in the tumor sample obtained by laparotomy. After a 34 months 400mg/day imatinib mesylate (Gleevec(®)) treatment a dramatic tumor regression was obtained.