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Background: The pathophysiology of sickle cell disease (SCD) is complex and involves nitric oxide depletion, increased inflammation/adhesion molecules and vaso-occlusion in addition to the chronic hemolytic anemia. This pathophysiology results in systemic clinical complications including recurrent episodes of severe pain, stroke, acute chest syndrome (ACS) and an increased susceptibility to infection. SCD severity varies among individuals and fetal hemoglobin (HbF) is known as a major modulator of the disease. To date, hydroxyurea (HU) is a known intervention that acts by increasing HbF in individuals with SCD. The increase in HbF reduces the risk of ‘sickling’ events and improves clinical outcomes. This is the first study on the use of HU in individuals with SCA in Tanzania.Methods: A case-control study to determine the proportion, indications, clinical and laboratory outcomes of SCD patients with HU use was conducted at Muhimbili National Hospital in Dar Es Salaam, Tanzania.Results: Forty-two patients with Sickle cell anemia (SCA) on HU treatment and 32 patients with SCA not on HU treatment were enrolled. The proportion of HU use by individuals with SCA at Muhimbili National Hospital was 10 per 1000. The mean HbF % was 9.8 ± 2.4 vs 6.2 ±1.4 for controls (P

Hematological and biochemical reference values in sickle cell disease (SCD) are crucial for patient management and evaluation of interventions. This study was conducted at Mu-himbili National Hospital (MNH) in Dar es Salaam, to establish laboratory reference ranges in SCD at steady-state. Patients were grouped into five age groups with respects to their sex. Aggregate functions were used to handle repeated measures within the indi-vidual level in each age group. A nonparametric approach was used to smooth the curves and a parametric approach was used to determine SCD normal ranges. Comparison between males and females and against the general population was documented. Data from 4,422 patients collected from 2004-2015 were analyzed. The majority of the patients (35.41%) were children aged between 5-11 years. There were no significant differences (p≥0.05) in mean corpuscular hemoglobin concentration (MCHC), lymphocytes, basophils and bilirubin direct observed between males and females. Significant differences (p

ObjectivesTo provide lay information about genetics and sickle cell disease (SCD) and to identify and address ethical issues concerning the Sickle Cell Disease Genomics of Africa Network covering autonomy and research decision-making, risk of SCD complications and organ damage, returning of genomic findings, biorepository, data sharing, and healthcare provision for patients with SCD.DesignFocus groups using qualitative methods.SettingSix cities in Ghana, Nigeria and Tanzania within communities and secondary care.ParticipantsPatients, parents/caregivers, healthcare professionals, community leaders and government healthcare representatives.ResultsResults from 112 participants revealed similar sensitivities and aspirations around genomic research, an inclination towards autonomous decision-making for research, concerns about biobanking, anonymity in data sharing, and a preference for receiving individual genomic results. Furthermore, inadequate healthcare for patients with SCD was emphasised.ConclusionsOur findings revealed the eagerness of patients and parents/caregivers to participate in genomics research in Africa, with advice from community leaders and reassurance from health professionals and policy-makers, despite their apprehensions regarding healthcare systems.

BackgroundSickle cell disease (SCD) is a recognized cause of childhood mortality. Tanzania has the fifth highest incidence of SCD (with an estimated 11 000 SCD annual births) worldwide. Although newborn screening (NBS) for SCD and comprehensive healthcare have been shown to reduce under-5 mortality by up to 94% in high-income countries such as the USA, no country in Africa has maintained NBS for SCD as a national health program. The aims of this program were to establish and evaluate NBS-SCD as a health intervention in Tanzania and to determine the birth prevalence of SCD.MethodsMuhimbili University of Health and Allied Sciences conducted NBS for SCD from January 2015 to November 2016. Dried blood spot samples were collected and tested for SCD using isoelectric focusing.ResultsScreening was conducted on 3981 newborns. Thirty-one (0.8%) babies had SCD, 505 (12.6%) had sickle cell trait and 26 (0.7%) had other hemoglobinopathies. Twenty-eight (90.3%) of the 31 newborns with SCD were enrolled for comprehensive healthcare.ConclusionsThis is the first report on NBS as a health program for SCD in Tanzania. The SCD birth prevalence of 8 per 1000 births is of public health significance. It is therefore important to conduct NBS for SCD with enrollment into a comprehensive care program.

Sickle cell anemia neurologic complications The collaboration aims at exploring the relationship between the cerebral vasculature and neurologic complications in Tanzanian children with sickle cell anemia (SCA). Cerebral vasculopathy in internal carotid, middle, anterior cerebral, and posterior

Background The distribution of human parvovirus B19 (HPV B19) infection is ubiquitous and occurs worldwide. The virus has high tropism to red blood cells progenitor's cells leading to temporary infection of bone marrow and transient arrest of erythropoiesis. People with frequent episodes of hemolytic anemia including sickle cell disease (SCD) and thalassemia are at increased risk of infection. This study aimed at assessing prevalence and factors associated with HPV B19 infections among hospitalized SCD patients. Methodology This was a cross-sectional hospital-based study among SCD patients hospitalized at Muhimbili National Hospital. HPV B19 was detected using RT-PCR. Hematological and Chemistry tests were done using Sysmex XT2000i and Chemistry analyzer respectively. Results A total of 329 SCD patients, median age 15 years (interquartile range 7-22 years) were tested for HPV B19. The prevalence of HPV B19 was 29%. In multivariate logistic regression model, HPV B19 infection was associated with pain (OR=4.28, 95%CI: 1.20-15.19; p=0.025), low neutrophil counts (OR=0.57, 95%CI: 0.35-0.92, p=0.022) and MCH (OR=0.92, 95%CI: 0.85-0.99; p=0.033). Individuals infected with HPV B19 had slightly higher prevalence of severe anaemia (30.4% vs. 20.3%, p=0.054) and HIV infection (6.0% vs. 2.1%, p=0.083) in the univariate analysis. Considering the effect of HPV B19 virus on spleen, aplastic anemia and platelet counts in SCD patients, our study did not find any association with these parameters (p=0.244; p= 0.205 and p=0.567 respectively). Conclusion The prevalence of HPV B19 among hospitalized SCD patients at MNH was high. SCD patients with HPV B19 were more likely to present with pain, low neutrophils levels, and MCH. HIV infection might be associated with a high risk of HPV infection in SCD patients; however, this requires further investigation.

Sickle cell disease (SCD) is one of the most common monogenic diseases in humans with multiple phenotypic expressions that can manifest as both acute and chronic complications. Although described more than a century ago, challenges in comprehensive disease management and collaborative research on this disease are compounded by the complex molecular and clinical phenotypes of SCD, environmental and psychosocial factors, limited therapeutic options and ambiguous terminology. This ambiguous terminology has hampered the integration and interoperability of existing SCD knowledge, and SCD research translation. The SCD Ontology (SCDO), which is a community-driven integrative and universal knowledge representation system for SCD, overcomes this issue by providing a controlled vocabulary developed by a group of experts in both SCD and ontology design. SCDO is the first and most comprehensive standardized human- and machine-readable resource that unambiguously represents terminology and concepts about SCD for researchers, patients and clinicians. It is built around the central concept ‘hemoglobinopathy’, allowing inclusion of non-SCD haemoglobinopathies, such as thalassaemias, which may interfere with or influence SCD phenotypic manifestations. This collaboratively developed ontology constitutes a comprehensive knowledge management system and standardized terminology of various SCD-related factors. The SCDO will promote interoperability of different research datasets, facilitate seamless data sharing and collaborations, including meta-analyses within the SCD community, and support the development and curation of data-basing and clinical informatics in SCD.

Sickle Cell Disease (SCD) is among the most common single-gene diseases in the world but evidence-based comprehensive health care has not been implemented where the highest prevalence of SCD occurs, in sub-Saharan Africa (SSA). It represents an urgent health burden, both in terms of mortality and morbidity with an estimated mortality of 8-16% in children under 5 years in SSA. Addressing the high mortality of SCD in SSA and for effective management of SCD, newborn screening (NBS) should be incorporated with prevention of infections (including pneumococcal septicaemia and malaria), parental education and support at all levels of healthcare provision to enable timely recognition. The NBS working group of the Africa Sickle Cell Research Network (AfroSickleNet) collaboration surveyed current projects in NBS in SSA, and current conditions that hinder more widespread implementation of NBS for SCD. Solutions based on new point-of-care testing technology to disseminate education, and implementation science approaches that leverage existing resources are proposed.

Acute chest syndrome (ACS) is a life-threatening complication of sickle cell disease (SCD) with blood transfusion an integral part in its management. Red cell exchange (RCE) transfusion is usually regarded as preferable to top-up transfusion, because it reduces the proportion of Hemoglobin (Hb) S while at the same time avoiding circulatory overload. Despite its obvious benefits, RCE is underutilized, particularly in low-resource settings which may be due to scarcity of blood products and of expertise in carrying out exchange transfusion. We report on a young woman with SCD with severe ACS who responded promptly and dramatically to a RCE of only 0.95 L (instead of the recommended 1.4 L) and had in the end an HbS level of 48% (instead of the recommended level below 30%). Limited RCE resulted in significant clinical improvement. We suggest that limited RCE may be of benefit than no RCE in SCD patients with ACS, particularly in settings where RCE is not available.

Summary Sickle cell disease (SCD) is the single most important genetic cause of childhood mortality globally. Tanzania has one of the highest annual births of SCD individuals in the world, estimated to reach 11 000 births a year. Without intervention, 50–90% of children will die in childhood. However, cost-effective interventions have the potential to reduce childhood mortality by up to 70%. The effects of SCD are multi-dimensional, ranging from causing high morbidity and mortality, and reducing the quality of life, to imposing a high socio-economic burden on individuals, families and health systems. In the past 12 years, the SCD programme in Tanzania has developed, with local and global partnerships, a systematic framework for comprehensive research that is integrated into providing healthcare, training and advocacy in SCD. This report outlines the approach and achievements of collective initiatives for management and control of SCD in Tanzania.

BACKGROUND Sickle cell disease (SCD) is the most common inherited disorder worldwide, with the highest burden in sub-Saharan Africa. The natural history of SCD is characterized by periods of steady state interspersed by acute episodes. The acute anemic crises may be transient and are precipitated by treatable factors like infections, nutritional deficiencies, and sequestration. Anemia is almost always present, although it occurs at different levels of severity. OBJECTIVE This paper describes the protocol of a cross-sectional study to determine the prevalence of severe anemia and associated factors among sickle cell patients hospitalized at the Muhimbili National Hospital. METHODS This is an ongoing, descriptive, cross-sectional, hospital-based study among individuals with SCD, admitted to the Muhimbili National Hospital in Dares Salaam, Tanzania. A minimum sample size of 369 was calculated based on the previous prevalence of hospitalizations due to severe anemia (20%) in the same cohort. We are using a piloted standardized case report form to document clinical and laboratory parameters following informed consent. Data analysis will be performed using Stata software. Severe anemia is defined as Hb RESULTS Enrolment commenced in January 2015 and concluded in September 2016. Complete data analysis will begin in February 2018. The study results are expected to be published in May 2018. CONCLUSIONS This protocol paper will provide a useful and practical model for conducting cross-sectional studies in hospitalized patients that cover a wide ranging of clinical and laboratory variables.