RESUMO
BACKGROUND: Haemoglobinopathies such as sickle cell disorder and glucose-6-phosphate dehydrogenase (G6PD) deficiency as well as differences in ABO blood groups have been shown to influence the risk of malaria and/or anaemia in malaria-endemic areas. This study assessed the effect of adding MNP containing iron to home-made weaning meals on anaemia and the risk of malaria in Ghanaian pre-school children with haemoglobinopathies and different ABO blood groups. METHODS: This study was a double-blind, randomly clustered trial conducted within six months among infants and young children aged 6 to 35 months in rural Ghana (775 clusters, n = 860). Participants were randomly selected into clusters to receive daily semiliquid home-prepared meals mixed with either micronutrient powder without iron (noniron group) or with iron (iron group; 12.5 mg of iron daily) for 5 months. Malaria infection was detected by microscopy, blood haemoglobin (Hb) levels were measured with a HemoCue Hb analyzer, the reversed ABO blood grouping microtube assay was performed, and genotyping was performed by PCR-RFLP analysis. RESULTS: The prevalence of G6PD deficiency among the study participants was 11.2%. However, the prevalence of G6PD deficiency in hemizygous males (8.5%) was significantly higher than that in homozygous females (2.7%) (p = 0.005). The prevalence rates of sickle cell traits (HbAS and HbSC) and sickle cell disorder (HbSS) were 17.5% and 0.5%, respectively. Blood group O was dominant (41.4%), followed by blood group A (29.6%) and blood group B (23.3%), while blood group AB (5.7%) had the least frequency among the study participants. We observed that children on an iron supplement with HbAS had significantly moderate anaemia at the endline (EL) compared to the baseline level (BL) (p = 0.004). However, subjects with HbAS and HbAC and blood groups A and O in the iron group had a significantly increased number of malaria episodes at EL than at BL (p < 0.05). Furthermore, children in the iron group with HbSS (p < 0.001) and the noniron group with HbCC (p = 0.010) were significantly less likely to develop malaria. CONCLUSIONS: Iron supplementation increased anaemia in children with HbAS genotypes and provided less protection against malaria in children with HbAC and AS and blood groups A and O. TRIAL REGISTRATION: clinicaltrials.gov Identifier: NCT01001871 . Registered 27/10/2009. REGISTRATION NUMBER: https://clinicaltrials.gov/ct2/show/record/NCT01001871 .
RESUMO
BACKGROUND: Iron fortification and micronutrient initiatives, specifically, vitamin A, and zinc supplementation are the most cost-effective developmental strategies against malnutrition and health emergencies in pre-school children. Iron-deficiency among pre-school children have been documented, however, studies evaluating the impact of immunoglobulin G (IgG) isotype responses among iron-fortified pre-school children in malaria endemic communities has not been assessed. We evaluated the impact of iron fortification on the IgG responses to GLURP R0, GLURP R2 and MSP3 FVO malaria-specific antigens among pre-school children in malaria endemic areas. METHODS: This community-based, placebo-controlled, double-blinded, cluster-randomized trial study was conducted in Wenchi Municipal and Tain District of Bono Region. The trial was registered at ClinicalTrials.gov-registered trial (Identifier: NCT01001871). Ethical approval was obtained and informed consent were sought from each participant parents/guardian. For the current objective, 871 children aged 6-35 months were screened, from which 435 children received semi-liquid home-made meals mixed with 12.5 mg of iron daily (intervention group), and 436 received micronutrient powder without iron (placebo group) for 5 months. Standardized clinical and epidemiological questionnaires were administered and blood samples taken to measure IgG responses to GLURP R0, GLURP R2 and MSP3 FVO recombinant antigens using the Afro Immunoassay (AIA) protocol. RESULTS: Baseline anthropometry, malaria diagnosis, anaemia and iron status, demographic features and dietary intake were identical among the groups (p > 0.05). After the intervention, there was no significant difference in the IgG response against GLUP R0, GLUP R2 and MSP3 FVO between the iron-containing micronutrient and placebo groups (p > 0.05). The iron-containing micronutrient powder group who were iron-sufficient or iron replete had significantly higher IgG response to GLURP R0 and GLURP R2 compared to iron-deficient and iron-deficiency anaemia in the same group (p < 0.05). The IgG responses to all the three malaria specific antigens were low among children without malaria episode but high among those with two and four episodes due to exposure differences. CONCLUSION: Iron fortification did not influence antibody response against endogenous malaria specific antigens among pre-school children in malaria endemic areas, however, IgG response to malaria specific antigens were high among children with sufficient iron status.
Assuntos
Antígenos de Protozoários/imunologia , Suplementos Nutricionais , Imunoglobulina G/imunologia , Ferro/uso terapêutico , Malária/imunologia , Pré-Escolar , Método Duplo-Cego , Feminino , Gana/epidemiologia , Humanos , Lactente , Masculino , Proteínas de Protozoários/imunologiaRESUMO
Anaemia in young sub-Saharan African children may be due to the double burden of malaria and iron deficiency. Primary analysis of a double-blind, cluster randomized trial of iron containing micronutrient powder supplementation in Ghanaian children aged 6 to 35 months found no difference in malaria risk between intervention and placebo groups. Here, we performed a secondary analysis of the trial data to assess the impact of long-term prophylactic iron fortificant on the risk of iron deficiency and anaemia in trial subjects. This population-based randomized-cluster trial involved 1958 children aged between 6 to 35 months, identified at home and able to eat semi-solid foods. The intervention group (n = 967) received a daily dose containing 12.5 mg elemental iron (as ferrous fumarate), vitamin A (400 µg), ascorbic acid (30 mg) and zinc (5 mg). The placebo group (n = 991) received a similar micronutrient powder but without iron. Micronutrient powder was provided daily to both groups for 5 months. At baseline and endline, health assessment questionnaires were administered and blood samples collected for analysis. The two groups had similar baseline anthropometry, anaemia, iron status, demographic characteristics, and dietary intakes (p > 0.05). Of the 1904 (97.2%) children who remained at the end of the intervention, the intervention group had significantly higher haemoglobin (p = 0.0001) and serum ferritin (p = 0.0002) levels than the placebo group. Soluble transferrin receptor levels were more saturated among children from the iron group compared to non-iron group (p = 0.012). Anaemia status in the iron group improved compared to the placebo group (p = 0.03). Continued long-term routine use of micronutrient powder containing prophylactic iron reduced anaemia, iron deficiency and iron deficiency anaemia among pre-school children living in rural Ghana's malaria endemic area.
Assuntos
Anemia Ferropriva/tratamento farmacológico , Compostos Ferrosos/uso terapêutico , Oligoelementos/uso terapêutico , Anemia Ferropriva/sangue , Anemia Ferropriva/epidemiologia , Ácido Ascórbico/uso terapêutico , Pré-Escolar , Suplementos Nutricionais , Feminino , Gana/epidemiologia , Hemoglobinas/análise , Humanos , Lactente , Masculino , Efeito Placebo , Vitamina A/uso terapêutico , Vitaminas/uso terapêutico , Zinco/uso terapêuticoRESUMO
BACKGROUND: Rapid diagnostic test (RDT) kits have been useful tools to screen for the presence of infection with malaria parasites. Despite the improvement, false results from RDTs present a greater challenge. The need for quality test kits is desirable. We evaluated the diagnostic accuracy of three malaria RDTs. METHOD: The team consented and enrolled 754 participants from the two major public hospitals in Kintampo districts of Ghana from June 2014 to August 2014. Venous blood samples were obtained by trained personnel and samples were screened for malaria using CareStart and SD Bioline HRP2 and HRP2 with pLDH based RDTs with blood slides for malaria microscopy as "gold standard". Geometric mean parasite densities were estimated and parasite densities were used to estimate the quantitative limits of the RDTs. The sensitivities, specificities and other performance criteria were calculated using statistical analytical software. RESULT: The median age of participants was 21 (range 5-31) years. There were 28.6% (215/752) were males and 71.4% (537/752) were females. Comparing with microscopy, the sensitivity, specificity, positive predictive value, negative predictive value and the ROC were for CareStart (HRP2), 98.2%, 66.5%, 82.6%, 95.6%, 0.82; for CareStart (HRP2/pLDH) 98.2%, 66.5%, 82.6%, 95.6%, 0.82 and for SD-Bioline (HRP2/pLDH) RDTs 98.2%, 69.2%, 84.2%, 96.0%, 0.84 respectively. The performance for all the kits were acceptable at a cut-off of 25 or more parasites/µl of blood. CONCLUSIONS: The diagnostic performance of the three malaria RDTs was acceptable, according to the World Health Organisation criteria, to detect densities ≥25 parasite/µl of blood. The RDTs with HRP2/pLDH targets were comparable to those with only HRP2 and could successfully substitute current and commonly used HRP2-based RDTs.
Assuntos
Antígenos de Protozoários/genética , Testes Diagnósticos de Rotina/métodos , L-Lactato Desidrogenase/genética , Malária Falciparum/diagnóstico , Plasmodium falciparum/genética , Proteínas de Protozoários/genética , Adolescente , Adulto , Criança , Estudos Transversais , Feminino , Gana , Humanos , Masculino , Kit de Reagentes para Diagnóstico , Reprodutibilidade dos Testes , Adulto JovemRESUMO
BACKGROUND: Home fortification using sachets of micronutrient powder (e.g. "Sprinkles") is a food-based approach offering an alternative to high dose vitamin A (VA) supplements for infants. The primary objective was to investigate the impact of VA-home fortification on infant VA pool size. The secondary objective was to compare VA status of infants assessed by the modified relative dose response (MRDR) test before and the (13)C-retinol isotope dilution ((13)C-RID) test in the same infants after vitamin A supplementation. METHODS: A randomized-controlled trial was conducted in 7-9 month old infants in Ghana. Eligible children were randomly allocated to receive a daily sachet of "Sprinkles" with or without VA for 5 months added to complementary foods. The MRDR test indirectly determined VA liver reserves at baseline and the (13)C-RID determined VA body pool at follow-up in the same cohort of children. RESULTS: At baseline, the MRDR values (95 % CI) for infants were comparable in the intervention and control groups: normal at 0·032 (SD 0·018) (0·025-0·038) and 0·031 (SD 0·018) (0·024-0·038), respectively. After intervention, total body stores (TBS) and liver retinol concentrations did not differ between intervention and control groups; TBS were 436 (SD 303) and 434 (SD 186) µmol, respectively, and estimated liver concentrations were 0·82 (SD 0·53) and 0·79 (SD 0·36) µmol/g liver, indicating adequate reserves in all children. CONCLUSIONS: Both the MRDR and (3)C-RID tests confirmed that the infants had adequate VA status before and after home fortification of their complementary foods. These tests offered more information than serum retinol concentrations alone, which predicted VA deficiency using current suggested cutoffs not corrected for inflammation status.
RESUMO
BACKGROUND: Glucose-6-phosphate dehydrogenase (G6PD) deficiency is the most widespread enzyme defect that can result in red cell breakdown under oxidative stress when exposed to certain medicines including antimalarials. We evaluated the diagnostic accuracy of CareStart G6PD deficiency Rapid Diagnostic Test (RDT) as a point-of-care tool for screening G6PD deficiency. METHODS: A cross-sectional study was conducted among 206 randomly selected and consented participants from a group with known G6PD deficiency status between February 2013 and June 2013. A maximum of 1.6ml of capillary blood samples were used for G6PD deficiency screening using CareStart G6PD RDT and Trinity qualitative with Trinity quantitative methods as the "gold standard". Samples were also screened for the presence of malaria parasites. Data entry and analysis were done using Microsoft Access 2010 and Stata Software version 12. Kintampo Health Research Centre Institutional Ethics Committee granted ethical approval. RESULTS: The sensitivity (SE) and specificity (SP) of CareStart G6PD deficiency RDT was 100% and 72.1% compared to Trinity quantitative method respectively and was 98.9% and 96.2% compared to Trinity qualitative method. Malaria infection status had no significant (P=0.199) change on the performance of the G6PD RDT test kit compared to the "gold standard". CONCLUSIONS: The outcome of this study suggests that the diagnostic performance of the CareStart G6PD deficiency RDT kit was high and it is acceptable at determining the G6PD deficiency status in a high malaria endemic area in Ghana. The RDT kit presents as an attractive tool for point-of-care G6PD deficiency for rapid testing in areas with high temperatures and less expertise. The CareStart G6PD deficiency RDT kit could be used to screen malaria patients before administration of the fixed dose primaquine with artemisinin-based combination therapy.