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1.
N Engl J Med ; 383(23): 2242-2254, 2020 12 03.
Article in English | MEDLINE | ID: mdl-33264546

ABSTRACT

BACKGROUND: Children who have been hospitalized with severe anemia in areas of Africa in which malaria is endemic have a high risk of readmission and death within 6 months after discharge. No prevention strategy specifically addresses this period. METHODS: We conducted a multicenter, two-group, randomized, placebo-controlled trial in nine hospitals in Kenya and Uganda to determine whether 3 months of malaria chemoprevention could reduce morbidity and mortality after hospital discharge in children younger than 5 years of age who had been admitted with severe anemia. All children received standard in-hospital care for severe anemia and a 3-day course of artemether-lumefantrine at discharge. Two weeks after discharge, children were randomly assigned to receive dihydroartemisinin-piperaquine (chemoprevention group) or placebo, administered as 3-day courses at 2, 6, and 10 weeks after discharge. Children were followed for 26 weeks after discharge. The primary outcome was one or more hospital readmissions for any reason or death from the time of randomization to 6 months after discharge. Conditional risk-set modeling for recurrent events was used to calculate hazard ratios with the use of the Prentice-Williams-Peterson total-time approach. RESULTS: From May 2016 through May 2018, a total of 1049 children underwent randomization; 524 were assigned to the chemoprevention group and 525 to the placebo group. From week 3 through week 26, a total of 184 events of readmission or death occurred in the chemoprevention group and 316 occurred in the placebo group (hazard ratio, 0.65; 95% confidence interval [CI], 0.54 to 0.78; P<0.001). The lower incidence of readmission or death in the chemoprevention group than in the placebo group was restricted to the intervention period (week 3 through week 14) (hazard ratio, 0.30; 95% CI, 0.22 to 0.42) and was not sustained after that time (week 15 through week 26) (hazard ratio, 1.13; 95% CI, 0.87 to 1.47). No serious adverse events were attributed to dihydroartemisinin-piperaquine. CONCLUSIONS: In areas with intense malaria transmission, 3 months of postdischarge malaria chemoprevention with monthly dihydroartemisinin-piperaquine in children who had recently received treatment for severe anemia prevented more deaths or readmissions for any reason after discharge than placebo. (Funded by the Research Council of Norway and the Centers for Disease Control and Prevention; ClinicalTrials.gov number, NCT02671175.).


Subject(s)
Anemia/drug therapy , Antimalarials/therapeutic use , Artemisinins/therapeutic use , Malaria/prevention & control , Quinolines/therapeutic use , Aftercare , Child, Preschool , Drug Combinations , Endemic Diseases , Female , Humans , Infant , Kenya/epidemiology , Malaria/epidemiology , Male , Patient Readmission/statistics & numerical data , Uganda/epidemiology
2.
Transfusion ; 63(7): 1354-1365, 2023 07.
Article in English | MEDLINE | ID: mdl-37255467

ABSTRACT

BACKGROUND: The true burden of COVID-19 in low- and middle-income countries remains poorly characterized, especially in Africa. Even prior to the availability of SARS-CoV-2 vaccines, countries in Africa had lower numbers of reported COVID-19 related hospitalizations and deaths than other regions globally. METHODS: Ugandan blood donors were evaluated between October 2019 and April 2022 for IgG antibodies to SARS-CoV-2 nucleocapsid (N), spike (S), and five variants of the S protein using multiplexed electrochemiluminescence immunoassays (MesoScale Diagnostics, Rockville, MD). Seropositivity for N and S was assigned using manufacturer-provided cutoffs and trends in seroprevalence were estimated by quarter. Statistically significant associations between N and S antibody seropositivity and donor characteristics in November-December 2021 were assessed by chi-square tests. RESULTS: A total of 5393 blood unit samples from donors were evaluated. N and S seropositivity increased throughout the pandemic to 82.6% in January-April 2022. Among seropositive individuals, N and S antibody levels increased ≥9-fold over the study period. In November-December 2021, seropositivity to N and S antibody was higher among repeat donors (61.3%) compared with new donors (55.1%; p = .043) and among donors from Kampala (capital city of Uganda) compared with rural regions (p = .007). Seropositivity to S antibody was significantly lower among HIV-seropositive individuals (58.8% vs. 84.9%; p = .009). CONCLUSIONS: Despite previously reported low numbers of COVID-19 cases and related deaths in Uganda, high SARS-CoV-2 seroprevalence and increasing antibody levels among blood donors indicated that the country experienced high levels of infection over the course of the pandemic.


Subject(s)
Blood Donors , COVID-19 , Humans , Uganda/epidemiology , SARS-CoV-2 , COVID-19 Vaccines , Seroepidemiologic Studies , COVID-19/epidemiology , Antibodies, Viral
3.
Transfus Med ; 33(3): 213-220, 2023 Jun.
Article in English | MEDLINE | ID: mdl-36703544

ABSTRACT

BACKGROUND AND OBJECTIVE: Blood donation is known to result in iron deficiency (ID), with a higher prevalence in females. There is little published data on the frequency of ID among blood donors in resource-poor settings. We determined the prevalence of ID in blood donors in Uganda. METHODS: We conducted a descriptive cross-sectional study at the Uganda Blood Transfusion Service, Kampala from December 2021 to February 2022. A sample of 500 whole blood donors was enrolled. The evaluation included demographic characteristics, donation history, nutritional history, complete blood count, and serum ferritin. The primary outcome was the proportion of donors with serum ferritin <15 µg/L. RESULTS: The median (IQR) serum ferritin was 25 (12-47) µg/L and 89 (52-133) µg/L among female and male donors respectively. The prevalence of iron deficiency (serum ferritin <15 µg/L) among donating individuals was 11.5% (8.7-14.9), while among low haemoglobin deferrals, 61.5% (50.9-71.1). The prevalence was high among females [33.0% (27.9-38.6)] compared with males [2.5% (1.0-5.8)], but even higher among females younger than 24 years [35.4% (29.2-42.1)]. Factors associated with ID (adjusted odds ratio, 95% Cl, and significance) were; female donors (15.81, 5.17, 48.28, p < 0.001) and a high RDW (6.89, 2.99, 15.90, p < 0.001). We found a moderate correlation between serum ferritin and RDW (r = -0.419 and -0.487 for males and females respectively). CONCLUSION: Iron deficiency is common among blood donors in Uganda, affecting mostly young female donors. Considerations to adopt evidence-based strategies to prevent and manage ID among blood donors-such as serum ferritin monitoring and iron supplementation are highly recommended.


Subject(s)
Anemia, Iron-Deficiency , Iron Deficiencies , Humans , Male , Female , Cross-Sectional Studies , Ferritins , Blood Donors , Uganda/epidemiology , Anemia, Iron-Deficiency/epidemiology , Hemoglobins/metabolism
4.
Vox Sang ; 117(12): 1398-1404, 2022 Dec.
Article in English | MEDLINE | ID: mdl-36342344

ABSTRACT

BACKGROUND AND OBJECTIVES: Haemolytic disease of the newborn (HDN) is an immune haemolytic anaemia from maternal alloantibodies. Rh immunoglobulin (RhIg) prophylaxis can prevent alloimmunization to the D antigen. However, RhIg is not universally available in Uganda. ABO incompatibility also causes HDN. We determined the prevalence of HDN among newborn infants with jaundice in Uganda. MATERIALS AND METHODS: We conducted a prospective cross-sectional study at Kawempe National Referral Hospital, Kampala, Uganda. Infants aged 0-14 days with neonatal jaundice (or total bilirubin >50 µmol/L) were enrolled. Clinical evaluation and laboratory testing, including ABO, RhD typing and maternal antibody screen, were performed. RESULTS: A total of 466 babies were enrolled. The mean (SD) age was 3.4 (1.5) days. Of newborn babies with jaundice, 17.2% (80/466) had HDN. Babies with HDN had lower haemoglobin (SD); 15.7 (2.7) compared with those without HDN; 16.4 (2.4) g/dL, p = 0.016; and a higher bilirubin (interquartile range); 241 (200-318) compared with those without HDN; 219 (191-263) µmol/L, p < 0.001. One baby had anti-D HDN, while 46/466 had HDN from an ABO incompatibility (anti-A 43.5% and anti-B 56.5%); 82% of babies with HDN also had suspected neonatal sepsis or birth asphyxia. About 79.2% (57/72) of mothers did not have ABO/Rh blood group performed antenatally. All infants with HDN survived except one. CONCLUSION: Among newborn infants with jaundice, HDN is not rare. The majority is due to ABO HDN affecting group A and group B babies equally. Ensuring routine ABO/Rh grouping for all pregnant women is an area for improvement.


Subject(s)
Blood Group Incompatibility , Erythroblastosis, Fetal , Infant, Newborn , Infant , Female , Humans , Pregnancy , Cross-Sectional Studies , Prospective Studies , Uganda/epidemiology , Blood Group Incompatibility/epidemiology , Erythroblastosis, Fetal/epidemiology , Erythroblastosis, Fetal/prevention & control , ABO Blood-Group System , Hemolysis , Rho(D) Immune Globulin , Isoantibodies
5.
BMC Pediatr ; 19(1): 27, 2019 01 18.
Article in English | MEDLINE | ID: mdl-30658602

ABSTRACT

BACKGROUND: In resource-poor settings, transfused children often experience recurrence of severe anemia (SA) following discharge from hospital. This study determined the factors associated with recurrent severe anemia (RSA) among previously transfused Ugandan children aged less than 5 years. METHODS: A case-control study was conducted in five hospitals in Uganda from March 2017 to September 2018. We prospectively enrolled 196 hospitalised children who had been transfused for severe anemia 2 weeks to 6 months prior to enrollment. Of these, 101 children (cases) were re-admitted with a hemoglobin [Hb] level of ≤6 g/dL and required transfusion; and 95 children (age-matched controls) were admitted for other clinical illness with a Hb > 6 g/dL. Children known to have sickle cell anemia, cancer, or bleeding disorders were excluded. Clinical and laboratory evaluation were done. Conditional logistic regression adjusted for age, was used to determine factors associated with RSA. RESULTS: The median time (IQR) between the earlier transfusion and enrollment was 3.5 (1.9-5.7) months for cases, and was 5.0 (2.9-6.0) months for controls (p-value = 0.015). Risk factors (adjusted odds ratio, 95% confidence interval, and significance) for development of RSA were: hemoglobinuria (36.33, 2.19-600.66, p = 0.012); sickle cell anemia - newly diagnosed (20.26, 2.33-176.37, p = 0.006); history of earlier previous transfusions (6.95, 1.36-35.61, p = 0.020) and malaria infection (6.47, 1.17-35.70, p = 0.032). CONCLUSION: Malaria chemoprevention, follow up visit for Hb check after discharge from hospital and sickle cell screening among previously transfused children represent practical strategies to prevent and identify children at risk for recurrent severe anemia. The cause of hemoglobinuria in children merits further investigations.


Subject(s)
Anemia/epidemiology , Anemia/therapy , Blood Transfusion , Age Factors , Case-Control Studies , Child, Preschool , Female , Humans , Infant , Male , Recurrence , Risk Factors , Severity of Illness Index , Uganda/epidemiology
8.
Malar J ; 17(1): 467, 2018 Dec 13.
Article in English | MEDLINE | ID: mdl-30545357

ABSTRACT

BACKGROUND: Evolutionary pressure by Plasmodium falciparum malaria is known to have favoured a large number of human gene adaptations, but there is surprisingly little investigation of the effect of malaria on human mitochondrial sequence variation. Plasmodium falciparum infection can cause severe malaria anaemia (SMA) with insufficient tissue oxygenation, lactic acidosis and death. Despite equal degrees of severe anaemia, some individuals develop lactic acidosis while others do not. A case-control study design was used to investigate whether differences in host mitochondrial gene sequences were associated with lactic acidosis in SMA. Full mitochondrial sequences were obtained from 36 subjects with SMA complicated by lactic acidosis and 37 subjects with SMA without lactic acidosis. The two groups were matched for age, sex, and degree of anaemia. RESULTS: Compared with the reference sequence, a median of 60 nucleotide variants per individual (interquartile range 4-91) was found, with an average frequency of 3.97 variants per 1000 nucleotides. The frequency and distribution of non-synonymous DNA variants in genes associated with oxidative phosphorylation were not statistically different between the two groups. Non-synonymous variants predicted to have the most disruptive effect on proteins responsible for oxidative phosphorylation were present at a similar frequency in both groups. CONCLUSIONS: Lactic acidosis in SMA does not appear to be consistently associated with the high prevalence of any mitochondrial gene variant.


Subject(s)
Acidosis, Lactic , Anemia , DNA, Mitochondrial/genetics , Malaria, Falciparum , Acidosis, Lactic/etiology , Acidosis, Lactic/genetics , Anemia/etiology , Anemia/genetics , Case-Control Studies , Child, Preschool , Female , Humans , Infant , Lactic Acid/blood , Malaria, Falciparum/complications , Malaria, Falciparum/genetics , Male , Oxidative Phosphorylation , Sequence Analysis, DNA , Uganda/epidemiology
9.
Am Heart J ; 183: 129-136, 2017 Jan.
Article in English | MEDLINE | ID: mdl-27302626

ABSTRACT

BACKGROUND: Prior studies have suggested that transfusion of stored red blood cells (RBCs) with increased levels of cell-free hemoglobin might reduce the bioavailability of recipient nitric oxide (NO) and cause myocardial strain. METHODS: Ugandan children (ages 6-60 months) with severe anemia and lactic acidosis were randomly assigned to receive RBCs stored 1-10 days versus 25-35 days. B-type natriuretic peptide (BNP), vital signs, renal function test results, and plasma hemoglobin were measured. Most children had either malaria or sickle cell disease and were thus at risk for reduced NO bioavailability. RESULTS: Seventy patients received RBCs stored 1-10 days, and 77 received RBCs stored 25-35 days. The median (interquartile range) cell-free hemoglobin was nearly 3 times higher in longer-storage RBCs (26.4 [15.5-43.4] µmol/L) than in shorter-storage RBCs (10.8 [7.8-18.6] µmol/L), P < .0001. Median (interquartile range) BNP 2 hours posttransfusion was 156 (59-650) pg/mL (shorter storage) versus 158 (59-425) pg/mL (longer storage), P = .76. BNP values 22 hours posttransfusion were 110 (46-337) pg/mL (shorter storage) versus 96 (49-310) pg/mL (longer storage), P = .76. Changes in BNP within individuals from pretransfusion to 2 hours (or 22 hours) posttransfusion were not significantly different between the study groups. BNP change following transfusion did not correlate with the concentration of cell-free hemoglobin in the RBC supernatant. Blood pressure, blood urea nitrogen, creatinine, and change in plasma hemoglobin were not significantly different in the 2 groups. CONCLUSION: In a randomized trial among children at risk for reduced NO bioavailability, we found that BNP, blood pressure, creatinine, and plasma hemoglobin were not higher in patients receiving RBCs stored for 25-35 versus 1-10 days.


Subject(s)
Anemia/therapy , Blood Preservation , Erythrocyte Transfusion , Natriuretic Peptide, Brain/blood , Acidosis, Lactic/therapy , Anemia/blood , Biological Availability , Blood Pressure , Child, Preschool , Creatinine/blood , Female , Hemoglobins/analysis , Humans , Infant , Male , Nitric Oxide/metabolism , Time Factors , Uganda
10.
Malar J ; 14: 511, 2015 Dec 21.
Article in English | MEDLINE | ID: mdl-26691827

ABSTRACT

BACKGROUND: Malaria is associated with haemolysis and the release of plasma haem. Plasma haem can cause endothelial injury and organ dysfunction, and is normally scavenged by haemopexin to limit toxicity. It was hypothesized that dysregulation of the haem-haemopexin pathway contributes to severe and fatal malaria infections. METHODS: Plasma levels of haemin (oxidized haem), haemopexin, haptoglobin, and haemoglobin were quantified in a case-control study of Ugandan children with Plasmodium falciparum malaria. Levels at presentation were compared in children with uncomplicated malaria (UM; n = 29), severe malarial anaemia (SMA; n = 27) or cerebral malaria (CM; n = 31), and evaluated for utility in predicting fatal (n = 19) vs non-fatal (n = 39) outcomes in severe disease. A causal role for haemopexin was assessed in a pre-clinical model of experimental cerebral malaria (ECM), following disruption of mouse haemopexin gene (hpx). Analysis was done using Kruskall Wallis tests, Mann-Whitney tests, log-rank tests for survival, and repeated measures ANOVA. RESULTS: In Ugandan children presenting with P. falciparum malaria, haemin levels were higher and haemopexin levels were lower in SMA and CM compared to children with UM (haemin, p < 0.01; haemopexin, p < 0.0001). Among all cases of severe malaria, elevated levels of haemin and cell-free haemoglobin at presentation were associated with subsequent mortality (p < 0.05). Compared to ECM-resistant BALB/c mice, susceptible C57BL/6 mice had lower circulating levels of haemopexin (p < 0.01), and targeted deletion of the haemopexin gene, hpx, resulted in increased mortality compared to their wild type littermates (p < 0.05). CONCLUSIONS: These data indicate that plasma levels of haemin and haemopexin measured at presentation correlate with malaria severity and levels of haemin and cell-free haemoglobin predict outcome in paediatric severe malaria. Mechanistic studies in the ECM model support a causal role for the haem-haemopexin axis in ECM pathobiology.


Subject(s)
Heme/analysis , Hemopexin/analysis , Malaria, Falciparum/pathology , Animals , Case-Control Studies , Child , Child, Preschool , Disease Models, Animal , Female , Haptoglobins/analysis , Hemoglobins/analysis , Humans , Infant , Malaria, Falciparum/epidemiology , Male , Mice , Mice, Inbred BALB C , Mice, Inbred C57BL , Plasma/chemistry , Prospective Studies , Survival Analysis , Uganda/epidemiology
11.
JAMA ; 314(23): 2514-23, 2015 Dec 15.
Article in English | MEDLINE | ID: mdl-26637812

ABSTRACT

IMPORTANCE: Although millions of transfusions are given annually worldwide, the effect of red blood cell (RBC) unit storage duration on oxygen delivery is uncertain. OBJECTIVE: To determine if longer-storage RBC units are not inferior to shorter-storage RBC units for tissue oxygenation as measured by reduction in blood lactate levels and improvement in cerebral tissue oxygen saturation among children with severe anemia. DESIGN, SETTING, AND PARTICIPANTS: Randomized noninferiority trial of 290 children (aged 6-60 months), most with malaria or sickle cell disease, presenting February 2013 through May 2015 to a university-affiliated national referral hospital in Kampala, Uganda, with a hemoglobin level of 5 g/dL or lower and a lactate level of 5 mmol/L or higher. INTERVENTIONS: Patients were randomly assigned to receive RBC units stored 25 to 35 days (longer-storage group; n = 145) vs 1 to 10 days (shorter-storage group; n = 145). All units were leukoreduced prior to storage. All patients received 10 mL/kg of RBCs during hours 0 through 2 and, if indicated per protocol, an additional 10 mL/kg during hours 4 through 6. MAIN OUTCOMES AND MEASURES: The primary outcome was the proportion of patients with a lactate level of 3 mmol/L or lower at 8 hours using a margin of noninferiority equal to an absolute difference of 25%. Secondary measures included noninvasive cerebral tissue oxygen saturation during the first transfusion, clinical and laboratory changes up to 24 hours, and survival and health at 30 days after transfusion. Adverse events were monitored up to 24 hours. RESULTS: In the total population of 290 children, the mean (SD) presenting hemoglobin level was 3.7 g/dL (1.3) and mean lactate level was 9.3 mmol/L (3.4). Median (interquartile range) RBC unit storage was 8 days (7-9) for shorter storage vs 32 days (30-34) for longer storage without overlap. The proportion achieving the primary end point was 0.61 (95% CI, 0.52 to 0.69) in the longer-storage group vs 0.58 (95% CI, 0.49 to 0.66) in the shorter-storage group (between-group difference, 0.03 [95% CI, -0.07 to ∞], P < .001), meeting the prespecified margin of noninferiority. Mean lactate levels were not statistically different between the 2 groups at 0, 2, 4, 6, 8, or 24 hours. Kaplan-Meier analysis and global nonlinear regression revealed no statistical difference in lactate reduction between the 2 groups. Clinical assessment, cerebral oxygen saturation, electrolyte abnormalities, adverse events, survival, and 30-day recovery were also not significantly different between the groups. CONCLUSIONS AND RELEVANCE: Among children with lactic acidosis due to severe anemia, transfusion of longer-storage compared with shorter-storage RBC units did not result in inferior reduction of elevated blood lactate levels. These findings have relevance regarding the efficacy of stored RBC transfusion for patients with critical tissue hypoxia and lactic acidosis due to anemia. TRIAL REGISTRATION: clinicaltrials.gov Identifier: NCT01586923.


Subject(s)
Acidosis, Lactic/therapy , Anemia/blood , Brain/metabolism , Erythrocyte Transfusion , Oxygen Consumption/physiology , Specimen Handling/methods , Acidosis, Lactic/blood , Acidosis, Lactic/etiology , Anemia/complications , Anemia/therapy , Child, Preschool , Erythrocyte Transfusion/methods , Erythrocyte Transfusion/mortality , Erythrocytes/physiology , Female , Hemoglobin A/metabolism , Humans , Infant , Lactates/blood , Male , Patient Outcome Assessment , Regression Analysis , Time Factors , Treatment Outcome , Uganda
12.
Rural Remote Health ; 15(4): 3591, 2015.
Article in English | MEDLINE | ID: mdl-26626014

ABSTRACT

INTRODUCTION: To produce health professionals who are oriented towards addressing community priority health needs, the training in medical schools has been transformed to include a component of community-based training. During this period, students spend a part of their training in the communities they are likely to serve upon graduation. They engage and empower local people in the communities to address their health needs during their placements, and at the same time learn from the people. During the community-based component, students are constantly supervised by faculty from the university to ensure that the intended objectives are achieved. The purpose of the present study was to explore student experiences of support supervision from university faculty during their community-based education, research and service (COBERS placements) and to identify ways in which the student learning can be improved through improved faculty supervision. METHODS: This was a cross-sectional study involving students at the College of Health Sciences, Makerere University, Uganda, who had a community-based component during their training. Data were collected using both questionnaires and focus group discussions. Quantitative data were analyzed using statistical software and thematic approaches were used for the analysis of qualitative data. RESULTS: Most students reported satisfaction with the COBERS supervision; however, junior students were less satisfied with the supervision than the more senior students with more experience of community-based training. Although many supervisors assisted students before departure to COBERS sites, a significant number of supervisors made little follow-up while students were in the community. Incorporating the use of information technology avenues such as emails and skype sessions was suggested as a potential way of enhancing supervision amidst resource constraints without faculty physically visiting the sites. CONCLUSIONS: Although many students were satisfied with COBERS supervision, there are still some challenges, mostly seen with the more junior students. Using information technology could be a solution to some of these challenges.


Subject(s)
Community Health Services/organization & administration , Faculty, Medical/organization & administration , Rural Health Services/organization & administration , Schools, Medical/organization & administration , Students, Medical/psychology , Career Choice , Cross-Sectional Studies , Developing Countries , Education, Medical, Undergraduate/methods , Female , Focus Groups , Humans , Interprofessional Relations , Male , Personal Satisfaction , Qualitative Research , Students, Medical/statistics & numerical data , Surveys and Questionnaires , Uganda , Young Adult
13.
Infect Immun ; 82(1): 371-9, 2014 Jan.
Article in English | MEDLINE | ID: mdl-24191300

ABSTRACT

The host immune response plays an important role in the onset and progression of cerebral malaria (CM). The complement system is an essential component of the innate immune response to malaria, and its activation generates the anaphylatoxin C5a. To test the hypothesis that C5a signaling contributes to the pathogenesis of CM, we investigated a causal role for the C5a receptors C5aR and C5L2 in a mouse model of experimental CM (ECM) induced by Plasmodium berghei ANKA infection, and using a case-control design, we examined levels of C5a in plasma samples from Ugandan children presenting with CM or uncomplicated malaria (UM). In the ECM model, C5aR(-/-) mice displayed significantly improved survival compared to their wild-type (WT) counterparts (P = 0.004), whereas C5L2(-/-) mice showed no difference in survival from WT mice. Improved survival in C5aR(-/-) mice was associated with reduced levels of the proinflammatory cytokines tumor necrosis factor (TNF) and gamma interferon (IFN-γ) and the chemokine, monocyte chemoattractant protein 1 (MCP-1) (CCL2). Furthermore, endothelial integrity was enhanced, as demonstrated by increased levels of angiopoietin-1, decreased levels of angiopoietin-2 and soluble ICAM-1, and decreased Evans blue extravasation into brain parenchyma. In the case-control study, the median levels of C5a at presentation were significantly higher in children with CM versus those in children with UM (43.7 versus 22.4 ng/ml; P < 0.001). These findings demonstrate that C5a is dysregulated in human CM and contributes to the pathogenesis of ECM via C5aR-dependent inflammation and endothelial dysfunction.


Subject(s)
Complement C5a/immunology , Malaria, Cerebral/immunology , Receptors, Chemokine/immunology , Receptors, Complement/immunology , Animals , Case-Control Studies , Child , Child, Preschool , Complement C5a/deficiency , Disease Models, Animal , Female , Humans , Infant , Inflammation/immunology , Male , Mice , Mice, Inbred C57BL , Receptor, Anaphylatoxin C5a , Receptors, Complement/deficiency , Receptors, Concanavalin A
15.
Malar J ; 13: 279, 2014 Jul 21.
Article in English | MEDLINE | ID: mdl-25047113

ABSTRACT

BACKGROUND: Severe and fatal malaria are associated with dysregulated host inflammatory responses to infection. Chitinase 3-like 1 (CHI3L1) is a secreted glycoprotein implicated in regulating immune responses. Expression and function of CHI3L1 in malaria infection were investigated. METHODS: Plasma levels of CHI3L1 were quantified in a case-control study of Ugandan children presenting with Plasmodium falciparum malaria. CHI3L1 levels were compared in children with uncomplicated malaria (UM; n = 53), severe malarial anaemia (SMA; n = 59) and cerebral malaria (CM; n = 44) using the Kruskall Wallis-test, and evaluated for utility in predicting fatal (n = 23) versus non-fatal (n = 80) outcomes in severe disease using the Mann Whitney U test, receiver operating characteristic curves, and combinatorial analysis. Co-culture of P. falciparum with human peripheral blood mononuclear cells and the Plasmodium berghei ANKA experimental model of cerebral malaria were used to examine the role of CHI3L1 in severe malaria. RESULTS: In children presenting with falciparum malaria, CHI3L1 levels were increased in SMA and CM versus UM (p < 0.001). Among severe malaria cases, CHI3L1 levels at presentation predicted subsequent death (area under receiver operating characteristic curve 0.84 [95% CI 0.76-0.92]) and in combination with other host biomarkers, predicted mortality with high sensitivity (100% [85.7-100]) and specificity (81.3% [71.3-88.3]). Plasmodium falciparum stimulated CHI3L1 production by human peripheral blood mononuclear cells in vitro. CHI3L1 was increased in plasma and brain tissue in experimental cerebral malaria, but targeted Chi3l1 deletion did not alter cytokine production or survival in this model. CONCLUSIONS: These data suggest that plasma CHI3L1 measured at presentation correlates with malaria severity and predicts outcome in paediatric SMA and CM, but do not support a causal role for CHI3L1 in cerebral malaria pathobiology in the model tested.


Subject(s)
Adipokines/blood , Lectins/blood , Malaria, Cerebral/blood , Malaria, Falciparum/blood , Adipokines/biosynthesis , Adipokines/genetics , Anemia/blood , Anemia/etiology , Animals , Area Under Curve , Biomarkers , Brain Chemistry , Case-Control Studies , Child , Child, Preschool , Chitinase-3-Like Protein 1 , Female , Gene Expression Regulation , Glycoproteins/deficiency , Glycoproteins/genetics , Glycoproteins/physiology , Host-Parasite Interactions , Humans , Infant , Lectins/biosynthesis , Lectins/genetics , Leukocytes, Mononuclear/metabolism , Malaria/blood , Malaria/genetics , Malaria, Cerebral/mortality , Malaria, Falciparum/complications , Male , Mice , Mice, Inbred C57BL , Plasmodium berghei , Plasmodium falciparum/physiology , Prognosis , Prospective Studies , ROC Curve , Statistics, Nonparametric , Th1 Cells/immunology , Uganda/epidemiology
16.
Lancet Glob Health ; 12(1): e33-e44, 2024 Jan.
Article in English | MEDLINE | ID: mdl-38097295

ABSTRACT

BACKGROUND: Severe anaemia is associated with high in-hospital mortality among young children. In malaria-endemic areas, surviving children also have an increased risk of mortality or readmission after hospital discharge. We conducted a systematic review and individual patient data meta-analysis to determine the efficacy of monthly post-discharge malaria chemoprevention in children recovering from severe anaemia. METHODS: This analysis was conducted according to PRISMA-IPD guidelines. We searched multiple databases on Aug 28, 2023, without date or language restrictions, for randomised controlled trials comparing monthly post-discharge malaria chemoprevention with placebo or standard of care among children (aged <15 years) admitted with severe anaemia in malaria-endemic Africa. Trials using daily or weekly malaria prophylaxis were not eligible. The investigators from all eligible trials shared pseudonymised datasets, which were standardised and merged for analysis. The primary outcome was all-cause mortality during the intervention period. Analyses were performed in the modified intention-to-treat population, including all randomly assigned participants who contributed to the endpoint. Fixed-effects two-stage meta-analysis of risk ratios (RRs) was used to generate pooled effect estimates for mortality. Recurrent time-to-event data (readmissions or clinic visits) were analysed using one-stage mixed-effects Prentice-Williams-Peterson total-time models to obtain hazard ratios (HRs). This study is registered with PROSPERO, CRD42022308791. FINDINGS: Our search identified 91 articles, of which 78 were excluded by title and abstract, and a further ten did not meet eligibility criteria. Three double-blind, placebo-controlled trials, including 3663 children with severe anaemia, were included in the systematic review and meta-analysis; 3507 (95·7%) contributed to the modified intention-to-treat analysis. Participants received monthly sulfadoxine-pyrimethamine until the end of the malaria transmission season (mean 3·1 courses per child [range 1-6]; n=1085; The Gambia), monthly artemether-lumefantrine given at the end of weeks 4 and 8 post discharge (n=1373; Malawi), or monthly dihydroartemisinin-piperaquine given at the end of weeks 2, 6, and 10 post discharge (n=1049; Uganda and Kenya). During the intervention period, post-discharge malaria chemoprevention was associated with a 77% reduction in mortality (RR 0·23 [95% CI 0·08-0·70], p=0·0094, I2=0%) and a 55% reduction in all-cause readmissions (HR 0·45 [95% CI 0·36-0·56], p<0·0001) compared with placebo. The protective effect was restricted to the intervention period and was not sustained after the direct pharmacodynamic effect of the drugs had waned. The small number of trials limited our ability to assess heterogeneity, its sources, and publication bias. INTERPRETATION: In malaria-endemic Africa, post-discharge malaria chemoprevention reduces mortality and readmissions in recently discharged children recovering from severe anaemia. Post-discharge malaria chemoprevention could be a valuable strategy for the management of this group at high risk. Future research should focus on methods of delivery, options to prolong the protection duration, other hospitalised groups at high risk, and interventions targeting non-malarial causes of post-discharge morbidity. FUNDING: The Research-Council of Norway and the Bill-&-Melinda-Gates-Foundation through the Worldwide-Antimalarial-Research-Network.


Subject(s)
Anemia , Antimalarials , Malaria , Child , Humans , Child, Preschool , Antimalarials/therapeutic use , Patient Discharge , Aftercare , Artemether/therapeutic use , Artemether, Lumefantrine Drug Combination/therapeutic use , Malaria/complications , Malaria/epidemiology , Malaria/prevention & control , Anemia/epidemiology , Drug Combinations , Kenya , Chemoprevention , Randomized Controlled Trials as Topic
17.
Malar J ; 12: 55, 2013 Feb 06.
Article in English | MEDLINE | ID: mdl-23388470

ABSTRACT

BACKGROUND: Severe malarial anaemia requiring blood transfusion is a life-threatening condition affecting millions of children in sub-Saharan Africa. Up to 40% of children with severe malarial anaemia have associated lactic acidosis. Lactic acidosis in these children is strongly associated with fatal outcomes and is corrected by blood transfusion. However, it is not known whether the storage age of blood for transfusion affects resolution of lactic acidosis. The objective of this pilot study was to evaluate the effect of blood storage age on resolution of lactic acidosis in children with severe malarial anaemia and demonstrate feasibility of conducting a large trial. METHODS: Children aged six to 59 months admitted to Acute Care Unit of Mulago Hospital (Kampala, Uganda) with severe malarial anaemia (haemoglobin ≤ 5 g/dL) and lactic acidosis (blood lactate ≥5 mmol/L), were randomly assigned to receive either blood of short storage age (one to 10 days) or long storage age (21-35 days) by gravity infusion. Seventy-four patients were enrolled and randomized to two equal-sized study arms. Physiological measurements, including blood lactate, oxygen saturation, haemoglobin, and vital signs, were taken at baseline, during and after transfusion. The primary outcome variable was the proportion of children whose lactic acidosis resolved by four hours after transfusion. RESULTS: Thirty-four of 37 (92%) of the children in the short storage treatment arm compared to 30/37 (81%) in the long storage arm achieved a blood lactate <5 mmol/L by four hours post transfusion (p value = 0.308). The mean time to lactic acidosis resolution was 2.65 hours (95% CI; 2.25-3.05) in the short storage arm, compared to 3.35 hours (95% CI; 2.60-4.10) in the long storage arm (p value = 0.264). CONCLUSION: Pilot data suggest that among children with severe malarial anaemia and lactic acidosis transfused with packed red blood cells, the storage age of blood does not affect resolution of lactic acidosis. The results support a larger and well-powered study which is under way. TRIAL REGISTRATION: clinicaltrials.gov NCT01580111.


Subject(s)
Acidosis, Lactic/therapy , Blood Transfusion/methods , Malaria/complications , Child, Preschool , Drug Storage/methods , Female , Hemoglobins/analysis , Humans , Infant , Lactic Acid/blood , Male , Oxygen/blood , Prospective Studies , Time Factors , Treatment Outcome
18.
Malar J ; 12: 105, 2013 Mar 19.
Article in English | MEDLINE | ID: mdl-23506269

ABSTRACT

BACKGROUND: Severe falciparum malaria (SM) pathogenesis has been attributed, in part, to deleterious systemic host inflammatory responses to infection. High mobility group box 1 (HMGB1) protein is an important mediator of inflammation implicated in sepsis pathophysiology. METHODS: Plasma levels of HMGB1 were quantified in a cohort of febrile Ugandan children with Plasmodium falciparum infection, enrolled in a prospective observational case-controlled study, using a commercial enzyme-linked immunosorbent assay. The utility of HMGB1 to distinguish severe malaria (SM; n = 70) from uncomplicated malaria (UM; n = 33) patients and fatal (n = 21) versus non-fatal (n = 82) malaria, at presentation, was examined. Receiver operating characteristic curve analysis was used to assess the prognostic accuracy of HMGB1. The ability of P. falciparum-parasitized erythrocytes to induce HMGB1 from peripheral blood mononuclear cells was assessed in vitro. The effect of an anti-HMGB1 neutralizing antibody on disease outcome was assessed in the experimental Plasmodium berghei ANKA rodent parasite model of SM. Mortality and parasitaemia was assessed daily and compared to isotype antibody-treated controls. RESULTS: Elevated plasma HMGB1 levels at presentation were significantly associated with SM and a subsequent fatal outcome in paediatric patients with P. falciparum infection. In vitro, parasitized erythrocytes induced HMGB1 release from human peripheral blood mononuclear cells. Antibody-mediated neutralization of HMGB1 in the experimental murine model of severe malaria failed to reduce mortality. CONCLUSION: These data suggest that elevated HMGB1 is an informative prognostic marker of disease severity in human SM, but do not support HMGB1 as a viable target for therapeutic intervention in experimental murine SM.


Subject(s)
Biomarkers/blood , HMGB1 Protein/blood , Malaria, Falciparum/pathology , Animals , Antibodies, Neutralizing/administration & dosage , Case-Control Studies , Child , Child, Preschool , Disease Models, Animal , Enzyme-Linked Immunosorbent Assay , Female , Humans , Immunoglobulins, Intravenous/administration & dosage , Infant , Malaria/drug therapy , Malaria/pathology , Malaria, Falciparum/mortality , Male , Mice , Mice, Inbred C57BL , Prognosis , Prospective Studies , ROC Curve , Treatment Outcome , Uganda
19.
Semin Hematol ; 60(4): 182-188, 2023 Sep.
Article in English | MEDLINE | ID: mdl-37863704

ABSTRACT

Setting priorities in healthcare is always contentious given the array of possible services at primary, secondary, and tertiary levels of care, not to mention potential public health interventions. The central goals in global policy have been reducing inequity within and between countries, protecting vulnerable groups (particularly women and children) and reducing the major communicable diseases which have historically been a major burden in lower- and middle-income countries. Here limited relative and absolute spending on healthcare have spurred a series of initiatives in Global Health over the last 50 years which have led to significant gains in measures of morbidity and mortality. Against this background there remains the continuing question of how to adapt current medical practice in higher income countries for training and planning of services in lower- and middle-income countries. Here, the historical development of Global Health is outlined, and lessons drawn from the surveys of the global burden of disease and health economic analysis to understand how we can apply these principles to define Global Hematology. It remains likely that in lower-income countries effort should be concentrated on developing laboratory services and blood transfusion, to allow safe and effective support for the assessment of treatment of anemia, sickle cell disease, maternal and child health and urgent surgery and obstetric services. However, the principles of Global Health, could also be used for hematological malignancies to develop a framework for Global Hematology for all settings.


Subject(s)
Anemia, Sickle Cell , Hematology , Child , Humans , Female , Quality-Adjusted Life Years , Disability-Adjusted Life Years , Capacity Building , Blood Transfusion
20.
Nat Commun ; 14(1): 5691, 2023 09 14.
Article in English | MEDLINE | ID: mdl-37709763

ABSTRACT

Severe malarial anaemia can be fatal if not promptly treated. Hospital studies may under-represent the true burden because cases often occur in settings with poor access to healthcare. We estimate the relationship of community prevalence of malaria infection and severe malarial anaemia with the incidence of severe malarial anaemia cases in hospital, using survey data from 21 countries and hospital data from Kenya, Tanzania and Uganda. The estimated percentage of severe malarial anaemia cases that were hospitalised is low and consistent for Kenya (21% (95% CrI: 7%, 47%)), Tanzania (18% (95% CrI: 5%, 52%)) and Uganda (23% (95% CrI: 9%, 48%)). The majority of severe malarial anaemia cases remain in the community, with the consequent public health burden being contingent upon the severity of these cases. Alongside health system strengthening, research to better understand the spectrum of disease associated with severe malarial anaemia cases in the community is a priority.


Subject(s)
Anemia , Malaria , Humans , Kenya/epidemiology , Tanzania/epidemiology , Anemia/epidemiology , Malaria/complications , Malaria/epidemiology , Hospitals
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