Bioclinical features of haemophilia patients in Benin in 2023: Towards better care.

OBJECTIVE: To analyse the demographic, clinical and laboratory data of Beninese patients with haemophilia. METHOD: A prospective survey was conducted in three different hospitals of Benin from April 2021 to March 2022, to analyse clinical and biological features of patients with haemophilia previously diagnosed or identified based on personal/family history. RESULTS: A total of 101 patients were studied, 97 with haemophilia A and 4 with haemophilia B, including 26 new cases identified after family investigation. Their median age was 11 years, and the most frequent initial manifestations were cutaneous-mucosal haemorrhages (29.70%) and post-circumcision haemorrhages (25.74%). Previous joint bleedings were present in 77% of them, with an arthropathy in 65 cases, which particularly affected the knees (75%), elbows (41%) and ankles (29%). Factor VIII (FVIII) levels combined with activated partial thromboplastin time (APTT) values did not always enable, as would be expected, the distinction between severe and moderate haemophilia, since they were >1 IU/dl in 31 of 74 patients with APTT > 80 s, and between 1 and 2 IU/dl in 26 other cases with previous joint haemorrhages, including 18 with chronic arthropathy. Therefore, for these patients, severe haemophilia could not be excluded, and this uncertainty probably reflects technical difficulties affecting the pre-analytical and analytical stages of the APTT and FVIII/IX assays. CONCLUSION: Our study proved that haemophilia is a significant reality in Benin, but also remains under-diagnosed in some districts of the country. In addition, more reliable biological tests are needed in the future to better define the severity of the disease and improve treatment of patients.

Acquired platelet defect associated with gabapentin treatment: a case-report.

Gabapentin, a structural analog of gamma-aminobutyric acid, is used to treat peripheral neuropathic pain. Here we report the first case of platelet function disorder associated with gabapentin treatment in a 44-year-old woman without a history of bleeding. She presented with mucocutaneous bleeding approximately 1 month after initiation of gabapentin and platelet function tests showed no aggregation to arachidonic acid and epinephrine, a defective response to ADP and a slightly decreased response to collagen. Gabapentin's imputability was supported by the fact that all platelet functions were normalized 6 days after drug discontinuation, with the simultaneous disappearance of bleedings.

[Influence of white blood cells count on parasite density in Malaria in children aged 6 to 59 months in Benin]. / Influence de la numération leucocytaire sur la densité parasitaire dans le paludisme simple chez les enfants de 6 à 59 mois au Bénin.

Background: For many years, the treatment of malaria was based on clinical presumptive diagnosis, making its differential diagnosis with other causes of hyperthermia difficult. This drug pressure has led to the emergence of Plasmodium strains resistant to the most commonly used antimalarial drugs. This is why in 2004, the health authorities decided to revise the policy of malaria management by adopting a new strategy based on the rational use of artemisininbased combination therapies after the biological confirmation of suspected malaria cases. The biological diagnosis is an essential part of malaria management. The gold standard technique for diagnosis is the thick drop combined with the calculation of parasite density (PD), which is determined on the basis of the number of parasites counted in a microscopic field against a proposed standard number of leukocytes. The number of leukocytes used to calculate the parasite density should ideally be the actual number of leukocytes in the patient per cubic millimetre of blood. However, in the absence of the availability of a blood count at the time of the thick drop, an average number of 8 000 leukocytes/mm3 was used by the World Health Organisation (WHO) to estimate the parasite density. Nonetheless, in Benin the average number of leukocytes adopted by the National Malaria Control Programme (PNLP) is 6 000/mm3. The aim of our study was to determine the impact of the leukocyte count on the calculation of the parasite density in cases of uncomplicated malaria. Method: The study was a cross-sectional study with an analytical aim and took place in 2 hospitals in Benin, the Klouékanmey zone hospital in the south of Benin and the Djougou health centre in the north. It involved a population of 476 children aged between 6 and 59 months who were seen in consultation and in whom the clinical diagnosis of simple Plasmodium falciparum malaria was suspected. Children aged between 6 and 59 months, weighing at least 5 kg, with an axillary temperature ≥ 37.5°C at the time of consultation or a history of fever in the last 24 hours or other symptoms pointing to the diagnosis of malaria were included. Infestation was mono-specific for Plasmodium falciparum. Informed consent was required from the child's parents or guardian. The criteria for non-inclusion in our study were the presence of at least one sign of malaria severity, signs of severe malnutrition or a febrile state related to underlying infectious diseases other than malaria. Thick blood count and haemogram were systematically performed in all included children. Parasite density was calculated according to 3 methods, first using a weighted leukocyte count of 6 000/mm3 recommended by the Benin National Malaria Control Programme (PNLP), then a leukocyte count of 8 000/mm3 recommended by the World Health Organisation and finally the patient's actual leukocyte count obtained from the blood count. It should be noted that these different samples were respectively taken on the day of inclusion in compliance with the conditions of the pre-analytical phase in force in our medical biology laboratory. Results: At the end of our study, 313 children, i.e. 65.76% of our study population had a positive white blood cell count with a positivity rate of 62.14% in Djougou, i.e. 174 children, and 70.9% in Klouékanmey, i.e. 139 children. The average leukocyte count in these children was 11,580/mm3. Among them, 205 children had an abnormal white blood cell count, i.e. 17 cases of leukopenia (5.43%) and 188 cases of hyperleukocytosis (60.06%). Using successively the average number of 6 000 leukocytes/mm3 proposed by the Benin PNLP and that of 8 000 leukocytes/mm3 proposed by the WHO, the average parasite densities were respectively 47,943 and 63,936 trophozoïtes/µl against 92,290 trophozoïtes/µl when the real number of leukocytes of the patients was used for the calculation of the PD. By using an average of 6 000 leukocytes/mm3 for PD calculation, 60% of the calculated PDs were underestimated and 6% were overestimated. Using an average of 8 000 leukocytes/mm3 resulted in 49% of PD being underestimated and 15% being overestimated. The difference between the three calculation methods was considered statistically significant (p value <0.05). Conclusion: The use of 6 000 or 8 000 coefficients for the estimation of parasitaemia could lead to a significant underestimation of the parasite load.

[Red blood cell alloimmunization among polytransfused patients in the National Hospital and University Center of Cotonou: about 51 cases]. / Allo-immunisation anti-érythrocytaire chez les polytransfusés au Centre National Hospitalier Universitaire de Cotonou: à propos de 51 cas.

Blood transfusion is a medical procedure used to treat patients with labile blood product. Each transfusion of globular concentrate exposes recipients to the risk of red blood cell alloimmunization. The test for red cell antibodies (RCA) ensures the immunohaematological safety of transfused patients. In Benin, this test is not performed in a systematic way or included either in the pre-transfusion or in the post-transfusion tests. The purpose of this study is to determine the presence of red cell antibodies among polytransfused patients. RCA was performed using indirect antiglobulin test on gel-filtration in 51 polytransfused patients including 26 selected in the Department of Hematology and 25 in the Department of Nephrology at the National Hospital and University Center of Cotonou. After phenotyping alloimmunized patients, tests for detecting signs of hemolysis were performed. Clinical data as well as those on transfusion were collected from transfusion registries and medical records. The prevalence of alloimmunization in our study population was 13.73%. The antibodies identified had the following characteristics: association of anti-RH1 and anti-RH3, anti LE1, association of anti-RH3 and anti-FY1. Alloantibodies were more frequent in patients who had received more than 15 packed red blood cells. Laboratory tests showed signs of hemolysis in one alloimmunized patient. There was no correlation between age, sex, clinical diagnosis and the occurrence of red blood cell alloimmunization. The test for red cell antibodies should be systematically performed in polytransfused patients in order to ensure better transfusion recipient safety in Benin.

Pathophysiology and Diagnosis of Drug-Induced Immune Thrombocytopenia.

Drug-induced immune thrombocytopenia (DITP) is a life-threatening clinical syndrome that is under-recognized and difficult to diagnose. Many drugs can cause immune-mediated thrombocytopenia, but the most commonly implicated are abciximab, carbamazepine, ceftriaxone, eptifibatide, heparin, ibuprofen, mirtazapine, oxaliplatin, penicillin, quinine, quinidine, rifampicin, suramin, tirofiban, trimethoprim-sulfamethoxazole, and vancomycin. Several different mechanisms have been identified in typical DITP, which is most commonly characterized by severe thrombocytopenia due to clearance and/or destruction of platelets sensitized by a drug-dependent antibody. Patients with typical DITP usually bleed when symptomatic, and biological confirmation of the diagnosis is often difficult because detection of drug-dependent antibodies (DDabs) in the patient's serum or plasma is frequently not possible. This is in contrast to heparin-induced thrombocytopenia (HIT), which is a particular DITP caused in most cases by heparin-dependent antibodies specific for platelet factor 4, which can strongly activate platelets in vitro and in vivo, explaining why affected patients usually have thrombotic complications but do not bleed. In addition, laboratory tests are readily available to diagnose HIT, unlike the methods used to detect DDabs associated with other DITP that are mostly reserved for laboratories specialized in platelet immunology.

[Emergency treatment of sickle cell diseases in the Blood Diseases Department at the Koutoukou Maga National Teaching Hospital, Cotonou, Benin]. / Urgences drépanocytaires au Service des Maladies du Sang du Centre National Hospitalier Universitaire-Hubert Koutoukou Maga de Cotonou, Benin.

INTRODUCTION: Evolution of sickle cell disease is marked by the occurrence of acute complications, some of which are real emergencies that can give rise to life-threatening or functional cosequences. This study aims to evaluate the frequency and the evolution of emergency treatment of sickle cell disease in the Blood Diseases Department at the Koutoukou Maga National Teaching Hospital, Cotonou. METHODS: We conducted a retrospective and descriptive study of all patients hospitalized for emergency treatment of sickle cell disease from January 2014 to December 2015. We excluded patients hospitalized for chronic sickle cell disease complications. RESULTS: Out of 813 hospitalizations, two hundred and four (204) emergency treatments of sickle cell disease were registered (prevalence 25%). The average age of our patients was 24.2 years. The most represented age group was 20-30 years (45.6%). Male sex predominated (60.8%). Pupils/students was the most represented group (55.9%). Acute pain was the primary reason for hospitalization to 63.7%. Normal homozygous individuals (SS) were mostly represented (72.1%). Osteoarticular vaso-occlusive complications predominated (70.1%). Documented infectious complications were dominated by malaria (27.5%). Decompensated anemia accounted for 30.4%. Therapeutic approach was based on hydration (85.3%). The average length of stay in hospital was 5.4 days. Outcome was favorable in 96,5% of cases. Mortality accounted for 2.5%. CONCLUSION: Emergency treatments of sickle cell disease are frequent. Early diagnosis as well as early and effective management are necessary. Ongoing training programs in emergency treatments of sickle cell disease are necessary to reduce mortality.