Biological Abnormalities of Hemostasis in Patients with Epistaxis or Menorrhagia in Yaoundé, Cameroon.

Introduction: In Cameroon, screening and diagnosis of minor hemorrhagic syndromes remain difficult and few research studies have been done to assess the magnitude of future bleeding risk and the burden of these disorders on quality of life. Epistaxis and menorrhagia are the two leading causes of bleeding disorders in the world population. Aim: The aim of this study was to investigate the biological abnormalities of hemostasis in patients with epistaxis and menorrhagia. Method: From January to December 2021, we conducted a cross-sectional study in six hospitals with a gynecology and ENT department. We selected patients who presented epistasis or menorrhagia through clinical file and made them pass an interview and biological exams. Venous blood collected on EDTA tube allowed us to measure full blood count, thin blood smear, and blood grouping. PT, APPT, and fibrinogen assay were measured from citrate platelet-poor plasma. This plasma stored at -20°C for a maximum of 3 months allowed us to measure vWF : Ag and vWF : CBA ELISA. The bleeding time was measured at the time of sampling. Result: In total, our study population consisted of 60 patients aged 01-45 years. Epistaxis (40%) and menorrhagia (29%) were the two main causes of bleeding complaints in our study, in addition to gingivorrhagia (15%) and prolonged bleeding after injury (03%). Almost 60% of the population had at least one abnormal hemostasis parameter. The main abnormalities found were low von Willebrand factor (30.19%), presence of macroplatelets (16.98%), prolonged bleeding time (15.09%), prolonged PT (15.09%), and low platelet count (¬07.55%). Conclusion: In Cameroon, bleeding disorders manifested by epistaxis and menorrhagia are mainly caused by abnormalities of primary hemostasis.

Homozygote drepanocytosis: Ferric status and inflammation in world and Africa: Review article and meta analysis.

Background and Aims: Major sickle cell syndromes are subjected to a high frequency of hemolysis, infections, oxidative stress, and vasooclusive crises which promote inflammation and iron balance disorders. We aimed to systematically review and analyze the studies in this patients addressing in general, and Africa in particular. Methods: The systematic review of published articles in the Pubmed and Google Scholar databases was carried out according to the recommendations of the PRISMA model. The case-control articles have been included. The data extracted from the articles were analyzed using statistical software R. The standardized mean difference (SMD) was used to assess the extent of the disease on the different variables studied. Results: At the end, 128 articles were obtained; but only 33 were elligible for meta-analysis. A SMD of -1.79 was obtained for hemoglobin between the sickle cell patients and the controls due to the deviation from the overall mean hemoglobin in the cases (8 ± 2 g/dL) and in controls (13 ± 3 g/dL). Sickle cell disease showed a significant extent on ferritin [SMD = 2.61; (95% confidence interval, CI: 2.39-2.83); (p < 0.01)] compared to non-sickle cell patients thus describing a higher risk for sickle cell sufferer to have ferritin disorders. The included studies also described the influence of sickle cell anemia on serum iron [SMD = 1.52; (95% CI: 1.32-1.76); (p < 0.01)] compared to normal subjects. The high risk of inflammation has been described as higher in sickle cell patients [SMD = 0.38; (95% CI: 0.25-0.50)], reflecting the moderate extent of sickle cell disease on inflammation. Conclusion: Patients with major sickle cell syndrome in inflammation have a higher risk of iron profile disorders compared to the normal population. Further studies are needed to explore mechanisms for preventing the deleterious effects of iron from this hemolysis, for example haptoglobin genotyping.

Transfusion safety in francophone African countries: an analysis of strategies for the medical selection of blood donors.

BACKGROUND: The goal of selecting a healthy blood donor is to safeguard donors and reduce the risks of infections and immunologic complications for recipients. STUDY DESIGN AND METHODS: To evaluate the blood donor selection process, a survey was conducted in 28 blood transfusion centers located in 15 francophone African countries. Data collected included availability of blood products, risk factors for infection identified among blood donor candidates, the processing of the information collected before blood collection, the review process for the medical history of blood donor candidates, and deferral criteria for donor candidates. RESULTS: During the year 2009, participating transfusion centers identified 366,924 blood donor candidates. A mean of 13% (range, 0%-36%) of the donor candidates were excluded based solely on their medical status. The main risk factors for blood-borne infections were having multiple sex partners, sexual intercourse with occasional partners, and religious scarification. Most transfusion centers collected this information verbally instead of having a written questionnaire. The topics least addressed were the possible complications relating to the donation, religious scarifications, and history of sickle cell anemia and hemorrhage. Only three centers recorded the temperature of the blood donors. The deferral criteria least reported were sickle cell anemia, piercing, scarification, and tattoo. CONCLUSIONS: The medical selection process was not performed systemically and thoroughly enough, given the regional epidemiologic risks. It is essential to identify the risk factors specific to francophone African countries and modify the current medical history questionnaires to develop a more effective and relevant selection process.

Reduction of the risk of transfusion-transmitted human immunodeficiency virus (HIV) infection by using an HIV antigen/antibody combination assay in blood donation screening in Cameroon.

BACKGROUND: Improving blood safety without introducing nucleic acid testing in blood screening may be possible using antigen/antibody (Ag/Ab) combination assays, especially in resource-poor countries. STUDY DESIGN AND METHODS: To evaluate the potential reduction of human immunodeficiency virus (HIV)-transmitted infection using such an assay, a study was carried out aimed to compare the routine strategy for blood screening (S1), combining a rapid test (Determine HIV-1/-2, Inverness) and an enzyme immunoassay (human HIV-1/-2, Human Diagnostic) with an HIV Ag/Ab assay (S2, Genscreen ULTRA HIV Ag-Ab, Bio-Rad) in 2000 blood donations tested in Cameroon. Western blot and HIV RNA polymerase chain reaction were used to confirm the infection in reactive donors, and genotype was determined in HIV RNA-positive samples. RESULTS: Of the 2000 donors, 3.1% were positive with S1 and 4.3% with S2. Of the 97 samples positive with S1 and/or S2 tested for confirmation, 54.7% were positive, 38.1% indeterminate, and 7.2% negative. There were significant differences between S1 and S2 in terms of sensitivity (S1, 79.2%; S2, 100%), irrespective of the genotype, and in specificity (S1, 99.0; S2, 98.3%). The most frequent genotype (49%) was CRF02_AG. CONCLUSIONS: A testing strategy using Genscreen ULTRA HIV Ag/Ab could prevent 55 HIV transmissions per 10,000 donations. However, this would be at a cost of discarding 170 per 10,000 negative donations that would test false positive, showing that the implementation of new techniques in blood screening need an optimization before routine use. Using confirmatory assays, HIV Ab prevalence in blood donors in Cameroon was estimated at 2.65%.

New insights into Human Pegivirus-1 (HPgV-1) genotypes diversity in sub-Saharan Africa.

In the framework of a viral discovery research program using metagenomics, Human Pegivirus-1 reads (HPgV-1, formerly known as GBV-C) were detected in plasma pools of healthy blood donors from seven sub-Saharan African countries. For five of these countries, Mauritania, Mali, Niger, Burundi and Madagascar, no data about HPgV-1 genotypes was reported to date. To confirm our metagenomic findings and further investigate the genotype diversity and distribution of HPgV-1 in Africa, 400 blood donations from these five localities as well as from Cameroon, the Democratic Republic of Congo (DRC) and the Burkina Faso were screened with a RT-nested PCR targeting the viral 5'NCR region. Amplified products were sequenced, and the virus was genotyped by phylogenetic analysis. Out of the 400 plasma samples tested, 65 were positive for HPgV-1 RNA and 61 were successfully genotyped. Among these, 54 strains (88.5%) clustered with genotype 1, six (9.8%) with genotype 2 and one (1.6%) with genotype 5. Genotype 1 was observed in all countries studied, except in Madagascar, genotype 2 was detected in Mauritania and Madagascar, and genotype 5 in DRC. Overall, our results extend the geographic distribution of HPgV-1 in Africa and provide six additional nearly complete genomes. Considering that some HPgV-1 genotypes have been reported as potential predictive indicators of lower disease progression in HIV-1 infected subjects, further investigations should be conducted to better understand the positive impact, if any, of this virus.

Cytokine levels of interleukin-2 and 7 amongst antiretroviral therapy success and failure HIV patients attending the University Teaching Hospital, Yaoundé, Cameroon.

BACKGROUND: Immune reconstitution complications (IRC) are a major problem faced by HIV treated patients world wide. Interleukin (IL)-2 and IL-7 play vital roles in peripheral T-cell homeostasis. Our study objective was to measure and compare the blood plasma levels of IL-2 and IL-7 amongst antiretroviral therapy (ART) patients attending the Yaoundé University Teaching Hospital, Cameroon. METHODS: We performed a cross-sectional study with 296 HIV positive patients enrolled between July 2017 and May 2018 at the Yaoundé University Teaching Hospital. IL-2, IL-7, T-cell profile counts and plasma viral load were measured on whole blood specimens. Data obtained were analyzed using Graph Pad Prism 5.0 and Epi info 7.0. Software. RESULTS: IL-2 and IL-7 plasma concentration levels were higher in patients with ART failure compared to ART success, with a mean SD of 19.4±8 and 17.1±6 pg /ml, 35.26±11 and 21.5±5 pg/ml, with p < 0.001 and < 0.001. There was a direct and significant correlation between viral load, IL-2 and IL-7 with p values = 0.028, and 0.020, respectively. There was an association between IL-2, IL-7 and viral load in relation to the duration on treatment (DT), with p values = 0.003 (R2=0.041, CI= 0.069 - 0.34) ,0.017 (R2=0.027, CI=-0.30 - 0.030), and 0.001 (R2=0.048, CI=-0.047-0.76). CONCLUSION: Considering that limited surrogate markers are availiable for monitoring immune reconstitution and high associated mortality rates, IL-2 and IL-7 could be a good immunological predictor for ART failure and success in HIV infected individuals.

Characteristics of blood donors and donated blood in sub-Saharan Francophone Africa.

BACKGROUND: The importance of blood safety in public health was recognized long ago, and data are essential to plan strategies to improve the status. This study aims to obtain data on blood donor and blood donation characteristics that would complement blood safety data from national and international organizations. MATERIALS AND METHODS: A questionnaire was sent to seven Francophone countries (Burkina Faso, Cameroon, Congo, Ivory Coast, Mali, Niger, and Rwanda) and was structured to obtain objective data on blood donors and donated blood and in administrative and technical organization. RESULTS: The results reflect a poor level of organization of blood transfusion centers in large regions of the African continent, insufficient supply of blood products, high prevalence of transfusion-transmitted infections, limited financial resources, a lack of well-trained personnel, and cultural obstacles. Six countries had less than 50% of their personnel trained in transfusion medicine. Only one country had the entire standard operating procedure written. Female donors represented less than 30% of the donors and the range of percentage of hepatitis B found in donors was 2.76% to 18.96%. CONCLUSION: The inclusion of these regions in future blood safety surveys and in the development of national blood transfusion programs is essential and will undoubtedly require the assistance of international organizations.

Transfusion safety on the African continent: an international quality control of virus testing in blood banks.

BACKGROUND: Following World Health Organization recommendations that a quality control (QC) system be implemented in African blood centers, a pilot study of the performance of human immunodeficiency virus antibody (anti-HIV), hepatitis B surface antigen (HBsAg), and hepatitis C virus antibody (anti-HCV) testing by several Sub-Saharan African blood centers was initiated. STUDY DESIGN AND METHODS: A reference laboratory sent a panel of 25 samples to six African blood center laboratories. The panel included eight negative samples; four anti-HIV-1­, one anti-HIV-2­, four anti-HCV­, and five HBsAg-positive samples; and three samples consisting of mixtures of two sera to mimic coinfections. Sensitivity, specificity, and overall quality (correct positive or negative status) scores were calculated. RESULTS: From the 21 sets of results obtained (seven for each virus), eight were from rapid tests (two for HIV, three for HBV, and three for HCV) and 13 were from enzyme immunoassays (EIAs; all HIV EIAs were antigen/antibody combination assays). Overall assay sensitivity was 98% for HIV, 75% for HBV, and 88% for HCV; agreement between blood centers using the same assay was good. Sensitivity of rapid tests was notably poorer than EIAs, with overall sensitivity quality scores of 64.5% for rapid tests (20% for HBsAg rapid tests) compared to 100% for EIAs. The overall specificity quality scores were 98.3 and 94.5% for EIAs and rapid tests, respectively. CONCLUSIONS: This pilot QC study organized for blood centers of Sub-Saharan Africa showed the feasibility of the approach despite some logistic constraints. Although interlaboratory variability was small, the poor performance of rapid tests, especially for HBsAg, raises policy questions about their use as the only screening assay.

[Causes of anaemia in African children aged 5 to 10 years]. / Etiologies de l'anémie chez l'enfant africain de 5 à 10 ans.

This study was conducted among two groups of 105 children in a hospital in Yaoundé, Cameroon, to determine the causes of anaemia in children aged 5- 10-years-old. The study group included children presenting clinical evidence of anaemia while the control group was made of children without anaemia. Both sets of children were matched for neighbourhoods within the city of Yaoundé. Each child had a complete physical examination, full blood count, haemoglobin electrophoresis, reticulocyte counts, and stool samples examined for parasites and hemoparasites. The mean haemoglobin level was 7.77 +/- 1.54 g/dL in the study group and 12.37 +/- 1.23 in the control group. The anaemia was mainly normocytic, normochromic and regenerative in the study group, usually associated with evidence of haemolysis. Patients with homozygous sickle cell disease were found only in the study group (n = 13; 12.3%). Malaria parasites were noted in 89 children (84.7%) in the study group, compared with 34 (32.4%) in the control group (p = 0.0004). Prevalence of intestinal parasites was similar in both groups (50.8%). Protein-calorie malnutrition was rare and was not associated with anemia. We conclude that both malaria and sickle cell anaemia play an important role in anaemia in children aged 5-10 years.

Prevalence of anti-hepatitis C antibodies and its co-infection with HIV in rural Cameroon.

OBJECTIVE: To evaluate the prevalence of the co-infection between the human immunodeficiency virus (HIV) and hepatitis C virus (HCV), and the prevalence of factors associated with HCV transmission in a rural Cameroonian community. RESULTS: The mean age of the 174 participants included in the study was 30.3 (standard deviation = 13.26) years (age range 12-77 years). the prevalence of HCV/HIV co-infection was 1.7% [95% confidence interval (CI) 1.1-5.9]. The prevalence of HCV and HIV were 6.3% (95% CI 2.9-10.3) and 6.9 (95% CI 5.2-11.3), respectively. Histories of scarification (62.1%), multiple sex partners (31.0%) and sexually transmitted diseases (66.1%) were the most common risk factors of HCV transmission in this study.

High prevalence of cyclovirus Vietnam (CyCV-VN) in plasma samples from Madagascan healthy blood donors.

Cycloviruses, small ssDNA viruses belonging to the Circoviridae family, have been suggested as possible causes of enteric, respiratory and neurological disorders in human patients. One of these species, cyclovirus-Vietnam (CyCV-VN), initially isolated from cerebrospinal fluid samples of patients with unexplained neurological disorders, has since been reported in serum samples from chronically patients infected with HBV, HCV or HIV, in Italy. On the other hand, CyCV-VN was not detected in serum samples from healthy individuals. Here, we report on a high prevalence of 43.4% (40/92) of CyCV-VN in plasma samples from asymptomatic blood donors from Madagascar. Interestingly, this virus was not detected by metagenomics and PCR in six other African countries, suggesting regional differences in CyCV-VN prevalence across Africa. Phylogenetic analysis based on the complete genomes showed that CyCV-VN sequences isolated from blood were most closely related to sequences previously reported from human stool in Madagascar. Further investigations using larger cohorts are required to determine the global epidemiology, the natural history and the pathological significance, if any, of CyCV-VN infection in humans.

Profile of blood cell abnormalities among antiretroviral therapy naïve HIV patients attending the Yaounde University Teaching Hospital, Cameroon.

BACKGROUND: Abnormal hemograms are common manifestations and important predictive tools for morbidity in the human immunodeficiency virus (HIV) infection. Few studies have been reported on the blood profile of HIV antiretroviral therapy (ART) naive subjects, therefore this study aimed to quantitatively and qualitatively describe the blood cell profile of HIV ART naive patients, and to describe the occurrence of the blood cytopenias by CD4 cell counts and WHO clinical stage. METHODS: This cross-sectional study of ART naive HIV patients was done at the Yaounde University Teaching Hospital (YUTH). For eligible participants, a structured questionnaire was filled and a clinical examination was done. Blood samples were collected for the measurement of full blood count and CD4 cell count. Blood films were made for the cytological examination of the blood samples and a reticulocyte count was done by the cresyl blue stain method. RESULTS: Of 81 cases reviewed, 66 (81.5%) had a blood cell disorder. The main qualitative blood disorders on the blood film were metamyelocytes (37.1%), toxic neutrophils (33.3%), stab neutrophils (29.6%), anisocytosis (35.6%) hypochromia (32.1%) and giant platelets (22.2%). Anaemia (62.9%) was the most common quantitative disorder of which 86.3% had low reticulocyte counts. Participants with low CD4 counts and advanced clinical stages had a greater occurrence of blood cytopenias (p-values <0.05). CONCLUSION: In the HIV infection, peripheral blood cell abnormalities affect all cell lineages, with anaemia being the most frequent single blood cell abnormality. Blood cytopenias mainly occur in advanced immunosuppression and clinical stages. Although all HIV patients may have blood cell disorders, those with advanced disease are more prone to develop them.

[The francophone Africa blood transfusion research network: a five-year report]. / Le groupe de recherches transfusionnelles d'Afrique francophone : bilan des cinq premières années.

There has been little blood safety research in sub-Saharan Africa, often consisting of local efforts whose findings had limited impact The "Francophone Africa Transfusion Research Network" was created in May 2007 with the objective of developing common evidence-based blood safety policies that may be adapted to each country's situation. The Group's activities to date have focused mainly on obtaining epidemiological and laboratory data on blood transfusion and on suggesting blood safety strategies, particularly in the field of TTIs. To carry out such research activities, the group works closely with the National Blood Transfusion Services (NBTS), the Regional Blood Transfusion Services (RBTS), the hospital blood banks (HBB) and collection stations. For the first 5years, four research priorities were identified: (i) descriptive studies of the characteristics of francophone African blood donors and blood centers; (ii) estimation of the residual risk of transfusion-transmitted major viral infections; (iii) an analysis of blood donor deferral strategies; and (iv) a description of TTI screening strategies and an external quality assurance system (EQAS) project. During this period, seven projects have been implemented at the national level and published and five multicenter studies were conducted and published. The present review reports the main observations and recommendations from those studies that could improve blood safety statute in Africa.

Screening for hepatitis C virus infection in a high prevalence country by an antigen/antibody combination assay versus a rapid test.

In low-income-countries, screening for hepatitis C virus (HCV) infection is often based on rapid tests (RT). Their lower sensitivity compared to enzyme immunoassay (EIA) suggests that newer HCV Antigen/Antibody (Ag/Ab) combination assays might have a role in such countries. To test this idea, 1998 blood donors were tested at the University Teaching Hospital blood bank in Yaoundé, Cameroon simultaneously with a RT (HCV rapid test, Human Diagnostics, Berlin, Germany) according to standard practice (S1) and with an Ag/Ab assay (Monolisa HCV Ag/Ab Ultra, Biorad, France) (S2). All discordant, borderline and reactive samples were submitted to confirmatory testing by immunoblot and/or HCV-RNA. Of the 86 (4.3%) samples positive with one or both strategies, 29 were confirmed negative, 37 positive and 20 were false positive or resolved infection. There was a significant difference in test sensitivity (p=0.01) between S1 (70.3%) and S2 (91.9%) but not in test specificity (99.4% and 98.6%, respectively). The benefit of the Ag/Ab assay in the detection of recent HCV seronegative infections could not be evaluated since no Antigen-only donations were identified. However, better Ag/Ab test sensitivity compared to RT supports the implementation of these newer immunoassays for HCV screening in the African blood bank setting.

Risk factors for transmission of HIV in a hospital environment of Yaoundé, Cameroon.

Risk factors for HIV transmission within a hospital setting were assessed using pre-structured questionnaires and observations. Of 409 respondents, 66.3% corresponded to the nursing staff, 14.4% doctors and 8.3% laboratory staff. The irregular use of gloves and other protective clothing for risky tasks, and recapping of needles after use were some of the risk factors identified, especially amongst nurses. Preventive measures were not always implemented by health personnel. More emphasis should be placed not only on diffusing universal precautions and recommendations for hospital staff safety, but accompanying measures for monitoring and evaluation of implementation of these standards are also indispensable.

Blood safety in Sub-Saharan Africa: a multi-factorial problem.

Although the World Health Organization (WHO) has set targets for safe blood by 2012, Sub-Saharan Africa remains confronted with multi-factorial issues that compromise blood safety in most countries of the region. Some of these include the development and implementation of national policies for transfusion, the recruitment of voluntary and unpaid donors, proper screening of collected blood as well as a strategy for its rational use in a setting already plagued by a high prevalence of blood-borne agents, poverty, and sometimes organizational deficits. Furthermore, the organization of hemovigilance, as well as quality systems that could monitor transfusion practices is lacking in these settings. There is no funding and global improvement of blood safety has to be cheap to be feasible. Specific solutions for the African continent need to be developed and implemented. This paper examines the current status and difficulties of blood safety in Africa and reviews available data on transfusion medicine in the region.