Evaluation of the diagnostic accuracy of a hemoglobin S and C screening test: Sickle Scan

New tools for the rapid diagnosis of hemoglobinosis could encourage the extension of their screening in Africa. Our goal was to assess the analytical performances of a rapid hemoglobin S and C detection test, the Sickle Scan. This was a cross-sectional study carried out in March 2019 at the Yopougon Teaching Hospital. The subjects followed for hemoglobinosis as well as the subjects seeking out an electrophoresis of their hemoglobin were included. We carried out the hemogram, the electrophoresis of hemoglobin at alkaline pH (reference method) coupled with the metabisulfite sickling test (Emmel test) and the rapid detection test to be evaluated. This immunochromatographic test is capable of detecting hemoglobins A, S, and C, and to infer the hemoglobin phenotype from there. The study recruited 191 individuals. The test detected hemoglobins S and C with a sensitivity of 99.4% and 97.7% respectively; a specificity of 93.3% and 99.3%. The positive likelihood ratio for hemoglobins S and C was 15 and 144 respectively. The negative likelihood ratio was 0.01 for hemoglobin S, and 0.02 for hemoglobin C. The intrinsic characteristics obtained make this test an interesting screening tool for hemoglobinosis S and C. Keywords: Diagnostic test, hemoglobinosis, Abidjan, sensitivity, specificity

Recherche des hémoglobinopathies qualitatives chez les hémophiles à Abidjan, Côte d’Ivoire

Introduction : L’hémophilie est une maladie héréditaire rare à transmission récessive liée au chromosome X. Les principaux  symptômes sont l’hémorragie, les hématomes, l’anémie et les douleurs articulaires dans les hémarthroses. Ces deux derniers signespeuvent se retrouver au cours des hémoglobinopathies. Ainsi, l’objectif de cette étude était de rechercher la présence d’hémoglobinopathies qualitatives dans une cohorte d’hémophiles suivis au service d’hématologie clinique du CHU de Yopougon.Méthodes : C’est une étude transversale qui s’est déroulée de Janvier à Juillet 2017 au niveau de l’unité d’hématologie du laboratoire central du CHU de Yopougon. Sur les prélèvements de 49 patients, ont été effectués l’hémogramme, l’électrophorèse de l’hémoglobine, le taux de prothrombine (TP), le temps de céphaline activée (TCA) et le dosage des facteurs VIII et IX par la méthode chronométrique.Résultats : La moyenne d’âge était de 17 ans avec 73,5% d’élèves et étudiants. Les hémarthroses (75,5%) et les hématomes (36,7%) constituaient l’essentiel des signes cliniques. La complication majeure était la déformation articulaire à 34,7%. Sur les 49 patients constituant la cohorte, le pourcentage d’hémophiles A était de 89.8% (44/49) et celui d’hémophiles B 10,2% (5/49), avec 81,6% (40/49) d’hémophiles sévères. La fréquence des hémoglobinopathies qualitatives est de 8,2% (4/49) avec 6,2% de trait drépanocytaire AS (3/49) et 2% d’hémoglobine AC (1/49).Conclusion : Cette étude a mis en évidence la présence d’hémoglobinopathies qualitatives, pouvant coexister avec l’hémophilie, ce qui peut compliquer la prise en charge et la qualité de vie des patients. Mots clés : Hémophilie, hémogramme, électrophorèse, Abidjan.   English title: Research of qualitative haemoglobinopathies in hemophiliacs in Abidjan, Côte d’Ivoire Introduction: Hemophilia is a rare hereditary disease with X-linked recessive inheritance. The main symptoms are haemorrhage, hematoma, anemia and joint pain associated with hemarthrosis. These last two signs can also be found during haemoglobinopathies. Thus, the objective of this study was to investigate the presence of qualitative haemoglobinopathies in a cohort of hemophiliacs followed in the clinical hematology department of Yopougon University Hospital. Methods: This is a cross-sectional study that took place from January to July 2017 at the hematology unit of the central laboratory of the Yopougon University Hospital. On the samples of 49 patients, blood count, haemoglobin electrophoresis, prothrombin time (PT), activated partial thromboplastin time (APTT) and factor VIII and IX were measured by the chronometric method. Results: The average age was 17 with 73.5% of students. Haemarthrosis (75.5%) and hematoma (36.7%) constituted the bulk of clinical signs. The major complication was joint deformity with 34.7%. Of the 49 patients in the cohort, the proportion of hemophiliacs A was 89.8% (44/49) and that of hemophiliac B was 10.2% (5/49), with 81.6% (40/49) of all patients showing severe haemophilia. The frequency of qualitative haemoglobinopathies was 8.2% (4/49) with 6.2% of haemoglobin AS or sickle cell trait (3/49) and 2% of haemoglobin AC (1/49). Conclusion: This study highlighted the presence of qualitative hemoglobinopathies that can coexist with hemophilia, which can  complicate the management and quality of life of patients. Keywords: Hemophilia, hemogram, electrophoresis, Abidjan.  &nbsp