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Background and Objectives Severe anaemia, for which a blood transfusion can be life saving, is common in hospitalized children in sub-Saharan Africa but blood for transfusion is often in short supply. Umbilical cord blood is usually thrown away but could be a useful source of red cells for small volume transfusions in young children in this setting. The objective of this study was to evaluate the attitudes of women using the maternity services of the provincial hospital in Mombasa, Kenya, towards cord blood donation and transfusion, and essential aspects of this process including informed consent and the acceptability of screening for human immunodeficiency virus (HIV) infection. Materials and Methods A structured questionnaire was developed based on data provided by focus group discussions with women attending the hospital's maternity unit and administered to women who had recently delivered at the hospital. Results Of the 180 women who completed a questionnaire, the donation and transfusion of cord blood were acceptable to 81% and 78%, respectively. Ninety per cent of women who supported cord blood donation were willing to undergo further HIV testing at the time of delivery. Seventy-seven per cent of women wanted informed consent to be sought for cord blood donation and 66% of these felt they could make this decision alone. Conclusion The donation of umbilical cord blood and its transfusion are acceptable to the majority of women delivering at Coast Provincial General Hospital, Mombasa. Findings from the study will benefit the planned cord blood donation programme at this facility. [ABSTRACT FROM AUTHOR]

HLA class-I and class-II allele frequencies and two-locus haplotypes were examined in 367 unrelated Melanesians living on the islands of Vanuatu and New Caledonia. Diversity at all HLA class-I and class-II loci was relatively limited. In class-I loci, three HLA-A allelic groups (HLA-A*24, HLA-A*34 and HLA-A*11), seven HLA-B alleles or allelic groups (HLA-B*1506, HLA-B*5602, HLA-B*13, HLA-B*5601, HLA-B*4001, HLA-B*4002 and HLA-B*2704) and four HLA-C alleles or allelic groups (HLA-Cw*04, HLA-Cw*01, HLA-Cw*0702 and HLA-Cw*15) constituted more than 90% of the alleles observed. In the class-II loci, four HLA-DRB1 alleles (HLA-DRB1*15, HLA-DRB1*11, HLA-DRB1*04 and HLA-DRB1*16), three HLA-DRB3-5 alleles (HLA-DRB3*02, HLA-DRB4*01 and HLA-DRB5*01/02) and five HLA-DQB1 alleles (HLA-DQB1*0301, HLA-DQB1*04, HLA-DQB1*05, HLA-DQB1*0601 and HLA-DQB1*0602) constituted over 93, 97 and 98% of the alleles observed, respectively. Homozygosity showed significant departures from expected levels for neutrality based on allele frequency (i.e. excess diversity) at the HLA-B, HLA-Cw, HLA-DQB1 and HLA-DRB3/5 loci on some islands. The locus with the strongest departure from neutrality was HLA-DQB1, homozygosity being significantly lower than expected on all islands except New Caledonia. No consistent pattern was demonstrated for any HLA locus in relation to malaria endemicity. [ABSTRACT FROM AUTHOR]

Focuses on the chicken pox and meningogoccocal disease in children. Association of influenza A and meningococcal diseases; Invasion of meningococci due to decrease mucosal resistance; Diseases associated with Neisseria meningitidis.

Sickle cell anemia (SCA) is common in sub-Saharan Africa where approximately 1% of births are affected. Severe anemia is a common cause for hospital admission within the region yet few studies have investigated the contribution made by SCA. The Transfusion and Treatment of severe anemia in African Children Trial (ISRCTN84086586) investigated various treatment strategies in 3983 children admitted with severe anemia (hemoglobin < 6.0 g/dl) based on two severity strata to four hospitals in Africa (three Uganda and one Malawi). Children with known-SCA were excluded from the uncomplicated stratum and capped at 25% in the complicated stratum. All participants were genotyped for SCA at trial completion. SCA was rare in Malawi (six patients overall), so here we focus on the participants recruited in Uganda. We present baseline characteristics by SCA status and propose an algorithm for identifying children with unknown-SCA. Overall, 430 (12%) and 608 (17%) of the 3483 Ugandan participants had known- or unknown-SCA, respectively. Children with SCA were less likely to be malaria-positive and more likely to have an affected sibling, have gross splenomegaly, or to have received a previous blood transfusion. Most outcomes, including mortality and readmission, were better in children with either known or unknown-SCA than non-SCA children. A simple algorithm based on seven admission criteria detected 73% of all children with unknown-SCA with a number needed to test to identify one new SCA case of only two. Our proposed algorithm offers an efficient and cost-effective approach to identifying children with unknown-SCA among all children admitted with severe anemia to African hospitals where screening is not widely available., (© 2022 The Authors. American Journal of Hematology published by Wiley Periodicals LLC.)

Owing to the rapid turnaround time in the assessment of haemoglobin level by point-of-care tests (POC Hb), these have grown in popularity and scope in large parts of the world. However, whilst POC testing for malaria and HIV remains has been integrated into patient management in Africa, the use of POC haemoglobin testing remains neglected by health services. The main users of transfusions (paediatric, maternity and trauma services) present largely as emergencies. Ward-based POC Hb could result in more rapid and accurate diagnosis of anaemia, contributing to saving of lives and at the same time reduce unnecessary transfusions which deplete the limited supplies of donated blood in Africa. Severe anaemia requiring transfusion is a major cause of paediatric admission in Africa. At a dissemination meeting to discuss the results of a large phase III paediatric transfusion trial and steps to implementation of the findings participants strongly recommended that one of the most pressing actions required was to prioritise the use of POC haemoglobin testing. This would facilitate implementation of the new transfusion algorithm, developed at the meeting, which refines patient management including blood transfusions. We present the rationale for the strongly recommended prioritisation of POC Hb, using paediatric transfusion as an exemplar., (© 2021 The Authors. British Journal of Haematology published by British Society for Haematology and John Wiley & Sons Ltd.)

The phase III Transfusion and Treatment of severe anaemia in African Children Trial (TRACT) found that conservative management of uncomplicated severe anaemia [haemoglobin (Hb) 40-60 g/l] was safe, and that transfusion volume (20 vs. 30 ml/kg whole blood equivalent) for children with severe anaemia (Hb <60 g/l) had strong but opposing effects on mortality, depending on fever status (>37·5°C). In 2020 a stakeholder meeting of paediatric and blood transfusion groups from Africa reviewed the results and additional analyses. Among all 3196 children receiving an initial transfusion there was no evidence that nutritional status, presence of shock, malaria parasite burden or sickle cell disease status influenced outcomes or modified the interaction with fever status on volume required. Fever status at the time of ordering blood was a reliable determinant of volume required for optimal outcome. Elevated heart and respiratory rates normalised irrespective of transfusion volume and without diuretics. By consensus, a transfusion management algorithm was developed, incorporating three additional measurements of Hb post-admission, alongside clinical monitoring. The proposed algorithm should help clinicians safely implement findings from TRACT. Further research should assess its implementation in routine clinical practice., (© 2021 The Authors. British Journal of Haematology published by British Society for Haematology and John Wiley & Sons Ltd.)

Sickle cell anemia (SCA) is the commonest severe monogenic disorders of humans. The disease has been highly characterized in high-income countries but not in sub-Saharan Africa where SCA is most prevalent. We conducted a retrospective cohort study of all children 0-13 years admitted from within a defined study area to Kilifi County Hospital in Kenya over a five-year period. Children were genotyped for SCA retrospectively and incidence rates calculated with reference to population data. Overall, 576 of 18,873 (3.1%) admissions had SCA of whom the majority (399; 69.3%) were previously undiagnosed. The incidence of all-cause hospital admission was 57.2/100 person years of observation (PYO; 95%CI 52.6-62.1) in children with SCA and 3.7/100 PYO (95%CI 3.7-3.8) in those without SCA (IRR 15.3; 95%CI 14.1-16.6). Rates were higher for the majority of syndromic diagnoses at all ages beyond the neonatal period, being especially high for severe anemia (hemoglobin <50 g/L; IRR 58.8; 95%CI 50.3-68.7), stroke (IRR 486; 95%CI 68.4-3,450), bacteremia (IRR 23.4; 95%CI 17.4-31.4), and for bone (IRR 607; 95%CI 284-1,300), and joint (IRR 80.9; 95%CI 18.1-362) infections. The use of an algorithm based on just five clinical features would have identified approximately half of all SCA cases among hospital-admitted children with a number needed to test to identify each affected patient of only fourteen. Our study illustrates the clinical epidemiology of SCA in a malaria-endemic environment without specific interventions. The targeted testing of hospital-admitted children using the Kilifi Algorithm provides a pragmatic approach to early diagnosis in high-prevalence countries where newborn screening is unavailable., (© 2017 The Authors American Journal of Hematology Published by Wiley Periodicals, Inc.)

Symptomatic severe malarial anaemia (SMA) has a high fatality rate of 30-40%; most deaths occur in children awaiting blood transfusion. Blood transfusion services in most of Africa are not capable of delivering adequate supplies of safe blood in a timely manner to critically ill children with SMA. Contrary to widely held belief, hypovolaemia, rather than heart failure, has emerged as a common complication in such children. We examined the safety of pre-transfusion management (PTM) by volume expansion, aimed at stabilizing children and obviating the urgency for blood transfusion. Kenyan children with severe falciparum anaemia (haemoglobin <5 g/dl) and respiratory distress were randomly assigned to 20 ml/kg of 4.5% albumin or 0.9% saline or maintenance only (control) while awaiting blood transfusion. PTM was apparently safe since it did not lead to the development of pulmonary oedema or other adverse events. There was no significant difference in the primary outcome [mean percentage reduction in base excess between admission and 8 h (95% confidence interval)] between the control group 42% (19-66%) albumin group 44% (32-57%) and saline group 36% (16-57%); adjusted analysis of variance F=0.31, P=0.7. However, the number of children requiring emergency interventions was significantly greater in the control group, four of 18 (22%) than the saline group 0 of 20 (P=0.03). We have established the safety of this PTM in children with SMA whilst awaiting blood transfusion at a hospital with an adequate blood-banking program. The impact on mortality should be assessed where blood transfusion services are unable to supply emergency transfusions.

Although alpha+ thalassaemia is the commonest haemoglobinopathy in the world, it is not known if it is associated with significant ineffective erythropoiesis, a fact of importance in interpreting its complex interaction with malaria. To study this problem, we have measured the concentrations of soluble transferrin receptor (sTIR) and ferritin in 181 children from Vanuatu with heterozygous (68) and homozygous (46) alpha+ thalassaemia, and normal controls (67). sTfR concentrations were significantly higher in both homozygotes (mean 3.1 mg/l, range 2.8-3.4) and heterozygotes (2.86 mg/l, 2.6-3.2) compared to the normal controls (2.48 mg/l, 2.3-2.7), suggesting that although globin chain imbalance is minimal, there is ineffective erythropoiesis in both these conditions. Age was also shown to significantly affect sTfR, with peak levels occurring in the 5-9 years age group. Ferritin concentrations showed a similar trend, being higher in the thalassaemic groups, although this did not reach statistical significance. No individuals had low ferritin concentrations, although two had significantly elevated sTfR levels. These observations suggest that the alpha+ thalassaemia phenotype includes an expansion of the erythron, and may suggest possible mechanisms for the increased susceptibility in babies with alpha thalassaemia to both P. falciparum and P. vivax malaria.

The alpha+ thalassaemias are the most common single gene disorders of humans, yet little is known about their haematological characteristics in childhood. Blood samples have been collected randomly from more than 2000 individuals in village communities in Vanuatu in the South West Pacific and analysed for alpha thalassaemia and associated haematological changes. Here we describe the haematological effects of the alpha+ thalassaemias from early childhood through to maturity in this population. Mean cell volume (MCV) and mean cell haemoglobin (MCH) levels in individuals of normal, heterozygous and homozygous genotype differed significantly from one another throughout the entire age range (2P < 0.05). In contrast, haemoglobin levels in heterozygous and homozygous individuals were well maintained throughout development. Adults of normal genotype attain Hb levels which are indistinguishable from Caucasian reference values, a finding made all the more remarkable given the high frequency of clinical malaria in this population. It is clear from these findings that haematological data are valuable in screening for carriers of alpha+ thalassaemia in this population. MCH is clearly the most sensitive discriminator. None of the homozygous adults tested had an MCH of > 27 pg, whereas < 10% of normals had a value of < 27 pg. These data provide reference values for areas in which the alpha+ thalassaemias are common and often confused with iron-deficiency anaemia.