Food insecurity is a growing issue in the United States. Iron deficiency is the most common form of nutritional deficiency in patients with endothelial dysfunction and vascular-related diseases. This preliminary study lays the groundwork for the “Nutrient deficiency-on-a-chip” model. Endothelial cells are cultured on mechanically tunable, enzymatically cross-linked gelatin and treated with deferoxamine, an iron chelator, or angiotensin II were used to simulate a nutrient deficient and diseased environment, respectively. As oxidative stress and disturbed barrier function are the most prevailing mechanism of angiotensin II and iron deficiency induced endothelial dysfunction, to test our model we investigated the changes in reactive oxygen species production and VE-cadherin expression in engineered endothelium. Both angiotensin II and deferoxamine treated engineered endothelium showed an increase in oxidative stress and disturbed barrier function. This in vitro model can be a useful tool to better understand disease mechanisms associated with nutrient deficiency and identify novel therapeutics.

Iron deficiency chlorosis (IDC) is a frequent problem in soybean [Glycine max (L.) Merr.] production on calcareous soils. Greenhouse and soil incubation experiments were established to evaluate pyritic lignite efficacy to supply Fe as compared to Fe-EDDHA and Fe-EDTA sources across contrasting IDC tolerance varieties grown on a slightly acid and a calcareous soil. Soybean IDC incidence was influenced by the soil properties and variety tolerance. All iron sources increased plant dry matter accumulation on the Leeper soil, whereas on the Marietta soil only lignite at 0.672 kg ha-1 produced an increase. Lignite at 0.336 kg ha-1 successfully improved Fe availability to the plant as reflected by an increase in Fe content. Furthermore, no differences were found between the low rate of lignite and the commercial fertilizers on any of the evaluated parameters. Results from this study indicate that pyritic lignite may serve as an acceptable source of Fe on problem soils to prevent IDC.

No description available.

Fe biofortification of potato is a promising strategy to prevent Fe deficiency worldwide either through traditional breeding or biotechnological approaches. These approaches require the identification of candidate genes to uptake, transport and store Fe in potato tubers. We employed multiple approaches including SNP genotyping, QTL analysis, identifying genes orthologous to Arabidopsis ferrome, yeast complementation assay and genetic transformation to avoid the limitation from a single approach. We revealed several candidate genes potentially associated with potato plant Fe acquisition, PGSC0003DMG400024976 (metal transporter), PGSC0003DMG400013297 (oligopeptide transporter), PGSC0003DMG400021155 (IRT1) and IRTunannotated (an ortholog to the IRT gene that is not annotated in the potato genome). The microorganisms in the rhizosphere react intensely with the various metabolites released by plant roots in a variety of ways such as positive, negative, and neutral. These interactions can influence the uptake and transport of micronutrients in the plant roots. Therefore, the contribution of soil microorganisms in the rhizosphere to improve Fe supply of plants may play a key role in Fe biofortification, especially under real world field-based soil scenarios. We thus investigated rhizosphere microbial community diversity in Andean potato landraces to understand the role of plant-microbial interaction in potato Fe nutrient cycling. From the analysis of the high-throughput Illumina sequences of 16S and ITS region of ribosomal RNA gene, we found that both potato landraces with low and high Fe content in tubers and a landrace on which low or high Fe content fertilizer was applied to the leaf surface had large impacts on the rhizosphere fungal community composition. Indicator species analysis (ISA) indicated that Operational Taxonomic Units (OTUs) contributing most to these impacts were closely related to Eurotiomycetes and Leotiomycetes in the phylum Ascomycota, Glomeromycetes in the phylum Glomeromycota and Microbotryomycetes in the phylum Basidiomycota. Lots of species from these groups have been shown to regulate plant mineral nutrient cycling. Our research revealed potential candidate genes and fungal taxa involved in the potato plant Fe nutrient dynamics, which provides new insights into crop management and breeding strategies for sustainable Fe fortification in agricultural production. / Ph. D.

A ingestão de dieta deficiente em ferro pode causar alterações estruturais no Sistema Nervoso Central (SNC) bem como no nervo óptico por prejuízo no processo de mielinização. Essas alterações geradas pela anemia ferropriva pós-natal não são satisfatoriamente revertidas após a reposição de ferro. A estimulação tátil e o enriquecimento ambiental podem reduzir e/ou evitar os efeitos prejudiciais desta desnutrição sobre o SNC. O objetivo deste estudo foi avaliar estrutural e quantitativamente, o nervo óptico de ratos Wistar com anemia ferropriva submetidos à estimulação tátil e recuperação nutricional. Foram utilizados 4 grupos: Controle (C), Anêmico (A), Recuperado Não Estimulado (RN) e Recuperado Estimulado (E), compostos aleatoriamente por 1 rata mãe e 6 filhotes machos. Os grupos foram divididos de acordo com a variável dieta oferecida, pela quantidade de ferro/kg de dieta (com nível adequado em ferro (C), deficiente em ferro (A) e com recuperação do nível adequado de ferro (R)). O grupo C foi alimentado com dieta contendo 35 mg de ferro/kg de dieta, e o grupo A, com 4 mg de ferro/kg de dieta, e os grupos Recuperados (RN e RE), com 4 mg de ferro/kg de dieta do dia 0 ao 21º dia e, 35 mg de ferro/kg de dieta a partir do 22º dia. Os grupos Recuperados foram classificados de acordo com a variável estimulação: Estimulado (E), grupo submetido à estimulação tátil do dia 0 ao 32º dia, e Não Estimulado (N). Durante o período de amamentação, as ratas mães se alimentaram da dieta determinada para cada grupo, e no período pós lactação os filhotes receberam as mesmas dietas de suas respectivas mães. No 21º dia as ratas mães foram eutanasiadas e no 32º dia, todos os filhotes foram anestesiados e perfundidos via transcardíaca com uma solução de salina tamponada (PBS) 0,05M, pH 7,3, tendo seus nervos ópticos dissecados e os fragmentos selecionados refixados em tetróxido de ósmio a 1% em tampão fosfato 0,1 M, pH 7,3 e então processados para inclusão em araldite. Da área total da secção transversal do nervo óptico foram selecionadas 2 áreas que corresponderam aproximadamente 30% do nervo para a realização de análises morfológica e morfométrica. Na análise morfológica os animais do grupo RE mostraram um aspecto muito semelhante às características dos animais do grupo C, e com melhor aspecto em relação aos grupos A e RN, apresentando grande quantidade de fibras nervosas mielínicas, uniformemente distribuídas, bem agrupadas e compactadas, com espaço intersticial reduzido. Na análise morfométrica, em relação ao número de vasos sanguíneos, os fatores dieta, recuperação e estimulação não apresentaram interferência. Em relação ao número de astrócitos, a estimulação não interferiu, e em relação a dieta, o grupo A apresentou maior número que os grupos C e RN. Na avaliação do número de oligodendrócitos, em relação ao fator dieta, o grupo RN apresentou maior número que os grupos C e A, os quais não apresentaram diferença estatisticamente significante entre si. Já para o fator estimulação, o grupo RE apresentou menor número de oligodendrócitos quando comparado ao RN. Podemos concluir que: 1 - a dieta utilizada foi eficaz no desenvolvimento de anemia ferropriva leve nas ratas mães e severa nos filhotes; 2 - a associação das técnicas de estimulação tátil e recuperação nutricional resultou em uma reorganização estrutural do nervo óptico, semelhante ao grupo C e 3 - tal associação não interferiu no número de vasos sanguíneos, entretanto, resultou em uma normalização do número de astrócitos e de oligodendrócitos / Inadequate intake of dietary iron can cause structural changes in the Central Nervous System (CNS) and, thus, in the optic nerve with impaired myelination process. These changes generated by postnatal iron deficiency anemia are not satisfactorily reversed after replacement iron. The tactile stimulation and environmental enrichment can reduce and/or prevent the damaging effects of malnutrition on the CNS. The objective of this study was to evaluate structural and quantitatively the optic nerve of Wistar rats with iron deficiency anaemia submitted to tactile stimulation and nutritional recovery. We used 4 groups: Control (C), Anemic (A), Recovered Not Stimulated (RN) and Recovered Stimulated (R), randomly composed of 1 adult female rat and 6 male newborns. These groups were divided according to the variable diet provided, the amount of iron/kg in the diet (with appropriate levels of iron (C), deficient in iron (A) and with recovery of the appropriate level of iron (R)). The Control (C) group was fed with ration containing 35 mg iron/kg diet and the Anemic (A) group, with 4 mg iron/kg diet, and the Recovered groups (RN and RE) with 4 mg iron/kg diet from day 0 to day 21, and 35 mg iron/kg from day 22. The Recovered groups were classified according variable stimulation: Stimulated (E), group submitted to tactile stimulation from day 0 to day 32, and Not Stimulated (N). During the breastfeeding period, the mother rats fed the diet given to each group, and after lactation period the puppies received the same diets of their mothers. At day 21, the female rats were euthanized and at day 32 all juveniles were anesthetized and perfused transcardially with a buffered saline solution (PBS) 0,05M, pH 7,3, having their optic nerves dissected, and selected fragments were fixed in osmium tetroxide 1% and phosphate buffer 0,1 M, pH 7,3, and then processed for embedding in Araldite. Were selected 2 areas of the total area of optic nerve cross-section which approximately corresponded to 30% of the nerve to perform morphological and morphometric analysis. In the morphological analysis the optic nerve of the animals in RE group showed a very similar structural aspect to the characteristics of the optic nerves in group C, and looking better than in groups A and RN, with lot of myelinated nerve fibers well grouped and compacted and this organization was present uniformly across the nerve, resulting in reduced interstitial space. In the morphometric analysis, the number of blood vessels, dietary factors, recovery and stimulation showed no interference, since all groups showed no statistically significant difference. Regarding to the number of astrocytes, the stimulation did not influence it and, regarding to diet, the group A presented a higher number of cells than groups C and RN. In assessing the number of oligodendrocytes, in relation to diet factor, RN group had a greater number of oligodendrocytes that C and A groups, which showed no significant statistically difference between them. As for the stimulation factor, the RE group had fewer oligodendrocytes than the RN. With the results can be concluded that: 1- the used diet was effective in the development of mild iron deficiency anaemia in mothers and severe in young rats; 2- the association of tactile stimulation and nutritional recovery techniques resulted in a structural reorganization of the optic nerve, similar to C group and 3- this association did not affect the number of blood vessels, however it resulted in a normalization of the number of astrocytes and oligodendrocytes

A ingestão de dieta deficiente em ferro pode causar alterações estruturais no Sistema Nervoso Central (SNC) bem como no nervo óptico por prejuízo no processo de mielinização. Essas alterações geradas pela anemia ferropriva pós-natal não são satisfatoriamente revertidas após a reposição de ferro. A estimulação tátil e o enriquecimento ambiental podem reduzir e/ou evitar os efeitos prejudiciais desta desnutrição sobre o SNC. O objetivo deste estudo foi avaliar estrutural e quantitativamente, o nervo óptico de ratos Wistar com anemia ferropriva submetidos à estimulação tátil e recuperação nutricional. Foram utilizados 4 grupos: Controle (C), Anêmico (A), Recuperado Não Estimulado (RN) e Recuperado Estimulado (E), compostos aleatoriamente por 1 rata mãe e 6 filhotes machos. Os grupos foram divididos de acordo com a variável dieta oferecida, pela quantidade de ferro/kg de dieta (com nível adequado em ferro (C), deficiente em ferro (A) e com recuperação do nível adequado de ferro (R)). O grupo C foi alimentado com dieta contendo 35 mg de ferro/kg de dieta, e o grupo A, com 4 mg de ferro/kg de dieta, e os grupos Recuperados (RN e RE), com 4 mg de ferro/kg de dieta do dia 0 ao 21º dia e, 35 mg de ferro/kg de dieta a partir do 22º dia. Os grupos Recuperados foram classificados de acordo com a variável estimulação: Estimulado (E), grupo submetido à estimulação tátil do dia 0 ao 32º dia, e Não Estimulado (N). Durante o período de amamentação, as ratas mães se alimentaram da dieta determinada para cada grupo, e no período pós lactação os filhotes receberam as mesmas dietas de suas respectivas mães. No 21º dia as ratas mães foram eutanasiadas e no 32º dia, todos os filhotes foram anestesiados e perfundidos via transcardíaca com uma solução de salina tamponada (PBS) 0,05M, pH 7,3, tendo seus nervos ópticos dissecados e os fragmentos selecionados refixados em tetróxido de ósmio a 1% em tampão fosfato 0,1 M, pH 7,3 e então processados para inclusão em araldite. Da área total da secção transversal do nervo óptico foram selecionadas 2 áreas que corresponderam aproximadamente 30% do nervo para a realização de análises morfológica e morfométrica. Na análise morfológica os animais do grupo RE mostraram um aspecto muito semelhante às características dos animais do grupo C, e com melhor aspecto em relação aos grupos A e RN, apresentando grande quantidade de fibras nervosas mielínicas, uniformemente distribuídas, bem agrupadas e compactadas, com espaço intersticial reduzido. Na análise morfométrica, em relação ao número de vasos sanguíneos, os fatores dieta, recuperação e estimulação não apresentaram interferência. Em relação ao número de astrócitos, a estimulação não interferiu, e em relação a dieta, o grupo A apresentou maior número que os grupos C e RN. Na avaliação do número de oligodendrócitos, em relação ao fator dieta, o grupo RN apresentou maior número que os grupos C e A, os quais não apresentaram diferença estatisticamente significante entre si. Já para o fator estimulação, o grupo RE apresentou menor número de oligodendrócitos quando comparado ao RN. Podemos concluir que: 1 - a dieta utilizada foi eficaz no desenvolvimento de anemia ferropriva leve nas ratas mães e severa nos filhotes; 2 - a associação das técnicas de estimulação tátil e recuperação nutricional resultou em uma reorganização estrutural do nervo óptico, semelhante ao grupo C e 3 - tal associação não interferiu no número de vasos sanguíneos, entretanto, resultou em uma normalização do número de astrócitos e de oligodendrócitos / Inadequate intake of dietary iron can cause structural changes in the Central Nervous System (CNS) and, thus, in the optic nerve with impaired myelination process. These changes generated by postnatal iron deficiency anemia are not satisfactorily reversed after replacement iron. The tactile stimulation and environmental enrichment can reduce and/or prevent the damaging effects of malnutrition on the CNS. The objective of this study was to evaluate structural and quantitatively the optic nerve of Wistar rats with iron deficiency anaemia submitted to tactile stimulation and nutritional recovery. We used 4 groups: Control (C), Anemic (A), Recovered Not Stimulated (RN) and Recovered Stimulated (R), randomly composed of 1 adult female rat and 6 male newborns. These groups were divided according to the variable diet provided, the amount of iron/kg in the diet (with appropriate levels of iron (C), deficient in iron (A) and with recovery of the appropriate level of iron (R)). The Control (C) group was fed with ration containing 35 mg iron/kg diet and the Anemic (A) group, with 4 mg iron/kg diet, and the Recovered groups (RN and RE) with 4 mg iron/kg diet from day 0 to day 21, and 35 mg iron/kg from day 22. The Recovered groups were classified according variable stimulation: Stimulated (E), group submitted to tactile stimulation from day 0 to day 32, and Not Stimulated (N). During the breastfeeding period, the mother rats fed the diet given to each group, and after lactation period the puppies received the same diets of their mothers. At day 21, the female rats were euthanized and at day 32 all juveniles were anesthetized and perfused transcardially with a buffered saline solution (PBS) 0,05M, pH 7,3, having their optic nerves dissected, and selected fragments were fixed in osmium tetroxide 1% and phosphate buffer 0,1 M, pH 7,3, and then processed for embedding in Araldite. Were selected 2 areas of the total area of optic nerve cross-section which approximately corresponded to 30% of the nerve to perform morphological and morphometric analysis. In the morphological analysis the optic nerve of the animals in RE group showed a very similar structural aspect to the characteristics of the optic nerves in group C, and looking better than in groups A and RN, with lot of myelinated nerve fibers well grouped and compacted and this organization was present uniformly across the nerve, resulting in reduced interstitial space. In the morphometric analysis, the number of blood vessels, dietary factors, recovery and stimulation showed no interference, since all groups showed no statistically significant difference. Regarding to the number of astrocytes, the stimulation did not influence it and, regarding to diet, the group A presented a higher number of cells than groups C and RN. In assessing the number of oligodendrocytes, in relation to diet factor, RN group had a greater number of oligodendrocytes that C and A groups, which showed no significant statistically difference between them. As for the stimulation factor, the RE group had fewer oligodendrocytes than the RN. With the results can be concluded that: 1- the used diet was effective in the development of mild iron deficiency anaemia in mothers and severe in young rats; 2- the association of tactile stimulation and nutritional recovery techniques resulted in a structural reorganization of the optic nerve, similar to C group and 3- this association did not affect the number of blood vessels, however it resulted in a normalization of the number of astrocytes and oligodendrocytes

Background Due to small iron stores and rapid growth during the first months of life, infants with low birth weight (LBW) are at risk of iron deficiency (ID). ID in infancy is associated with irreversible impaired neurodevelopment. Preventive iron supplementation may reduce the risk of ID and benefit neurodevelopment, but there is also a possible risk of adverse effects. More than 50% of all LBW infants are born with marginally LBW (MLBW, 2000-2500g), and it is not known if they benefit from iron supplementation. Methods We randomized 285 healthy, Swedish, MLBW infants to receive 3 different doses of oral iron supplements; 0 (Placebo), 1, and 2 mg/kg/day from six weeks to six months of age. Iron status, during and after the intervention was assessed and so was the prevalence of ID and ID anemia (IDA), growth, morbidity and the interplay with iron and the erythropoetic hormones hepcidin and erythropoietin (EPO). As a proxy for conduction speed in the developing brain, auditory brainstem response (ABR) was analyzed at six months. In a follow up at 3.5 years of age, the children were assessed with a cognitive test (WPPSI-III) and a validated parental checklist of behavioral problems (CBCL), and compared to a matched reference group of 95 children born with normal birth weight. Results At six months of age, the prevalence of ID and IDA was significantly higher in the placebo group compared to the iron supplemented infants. 36% had ID in the placebo group, compared to 8% and 4 % in the 1 and 2mg/kg/day-groups, respectively. The prevalence of IDA was 10%, 3% and 0%, respectively. ABR-latencies did not correlate with the iron intake and was not increased in infants with ID or IDA. ABR wave V latencies were similar in all three groups. Hepcidin correlated to ferritin and increased in supplemented infants while EPO, which was negatively correlated to iron status indicators, decreased. At follow up there were no differences in cognitive scores between the groups but the prevalence of behavioral problems was significantly higher in the placebo group compared to those supplemented and to controls. The relative risk increase of CBCL-scores above a validated cutoff was 4.5 (1.4 – 14.2) in the placebo-group compared to supplemented children. There was no detected difference in growth or morbidity at any age. Conclusion MLBW infants are at risk of ID in infancy and behavioral problems at 3 years of age. Iron supplementation at a dose of 1-2 mg/kg/day from six weeks to six months of age reduces the risks with no adverse effects, suggesting both short and long term benefit. MLBW infants should be included in general iron supplementation programs during their first six months of life.

Actualmente la anemia ferropénica, es un problema de salud a nivel mundial, con mayor prevalencia en la niñez, por lo tanto, la madre opta por conductas basadas en conocimientos, actitudes y prácticas. El objetivo general fue: Determinar la relación que existe entre conocimientos, actitudes y prácticas de alimentación y anemia ferropénica en niños de 6 a 24 meses, en el Centro de Salud San Ignacio- 2019. Fue de tipo cuantitativo, diseño no experimental, descriptivo correlacional. Se realizo en el centro de salud San Ignacio, con una población de 80 madres, la muestra fue censal, el muestreo por conveniencia. El instrumento fue un cuestionario validado por juicio de expertos según prueba V de Aiken=1, la confiabilidad se probó mediante alfa de Conbrach con puntaje de 0.794. se tuvieron en cuenta las consideraciones éticas de Belmont: En cuanto a la dimensión conocimientos 70% tiene nivel adecuado y 30% inadecuado; asimismo la dimensión actitudes 52.5% es inadecuado y 47,5% adecuado y la dimensión práctica predomina el nivel inadecuado con 57,5% 42,5% están en niveles adecuados. En lo que respecta al tipo de anemia ferropénica de los niños de 6 a 24 meses prevalece la anemia leve con 87,5%, 12,5% anemia moderada y 0% anemia severa. En conclusión, existe relación significativa entre la dimensión actitudes de alimentación de las madres de niños de 6 a 24 meses en cuanto a los niveles de anemia ferropénica con una significancia bilateral de 0,025; esto indica asociación inversa entre ambas variables. / Currently, iron deficiency anemia is a worldwide health problem, with a higher prevalence in children, therefore, the mother chooses behaviors based on knowledge, attitudes and practices. The general objective was: To determinate the relationship between knowledge, attitudes and feeding practices and iron deficiency anemia in children aged 6 to 24 months, at the San Ignacio Health Center – 2019. The study was quantitative, descriptive, non-experimental design, cross-sectional descriptive-correlational type. It was conducted in the San Ignacio Health Center, with a population of 80 mothers, the sample was census, convenience sampling. The instrument was a questionnaire validated by expert judgment according to Aiken’s V test = 1 and pilot test with Cronbach’s alpha, which yielded a score of 0.794. Belmont Ethical considerations. The results: Regarding the knowledge dimension, 70% have an adequate level and 30% inadequate; likewise, the attitudes dimension 52.5% is inadequate and 47.5% adequate and the practical dimension is dominated by the inadequate level with 57.5% and 42.5% represents adequate levels. Concerning the type of iron deficiency anemia in children aged 6 to 24 months, mild anemia prevails with 87.5%, 12.5% moderate anemia and 0% severe anemia. It is concluding mother have basic knowledge about nutrition and iron deficiency anemia, however, they have weaknesses in terms of attitudes and practices. In conclusion, there is a significant relationship between the feeding attitudes dimension of mothers of children from 6 to 24 months in terms of the levels of iron deficiency anemia with a bilateral significance of 0.025; This indicates an inverse association between both variables.

Background The potential dire consequences of iron deficiency (ID) and iron deficiency anaemia (IDA) on childhood development are of major public health concern. Many factors contribute to anaemia, ID being only one progressive factor. The prevalence of ID and IDA must be accurately determined before iron intervention strategies can be safely prescribed. There is continued uncertainty regarding the optimal approach to identifying and measuring ID, as indicators have different roles, explore different aspects of iron metabolism and cannot be directly compared. Furthermore, inflammation and infection have a confounding effect on the commonly applied indicator and acute phase reactant, serum ferritin (SF). In the public health setting, a suitable method to assess iron status in developing countries has to be inexpensive, standardised, established, easy to measure and its applications specific to identifying ID. Aim We conducted secondary analysis of screening data from three independent iron intervention studies to critically evaluate the indicators used to determine iron status in 6-11-year-old primary school children from three South African provinces. Study design and methods A cross-sectional descriptive analysis was performed on the screening data collected in 2009 and 2010 during iron intervention studies in KwaZulu-Natal (n=736), Northern Cape (n= 1045), and North West (n=546). The three distinct study sites were analysed independently and collectively. Children’s haemoglobin (Hb), SF, transferrin receptor (TfR), zinc protoporphyrin (ZPP), and C-reactive protein (CRP) concentrations were measured and body iron calculated. ID prevalence was compared using different methods (namely the single indicators SF, TfR and ZPP, body iron and the multiple criteria model), and the influence of inflammation on SF was considered. Literature suggests that the multiple criteria model provides a more complete assessment of iron status. The performance of single and body iron indicators were compared to the multiple criteria model (by assessing sensitivity, specificity and predictive values). Results Significant positive correlations between CRP (indicator of inflammation) and SF existed in all study sites and the combined sample (p < 0.01). The mean SF concentration was substantially higher in subjects with inflammation than those without. A different SF cut-off to identify ID was applied to subjects with inflammation. The percentage of ID subjects varied using different indicators (4.2 – 26.5% in KwaZulu-Natal; 4.1 – 13.4% in Northern Cape; 7.0 – 24.4% in North West; and 5.4 – 15.2% in the combined sample). The sensitivity, specificity and predictive values of alternate ID indicators varied within and between study sites, compared to the multiple criteria model. Conclusion Simply using Hb as an ID indicator is inaccurate. The vast differences between percentages identified as ID by different indicators is reason for concern. No consistent agreement appeared between single ID indicators, body iron and the multiple criteria model for ID identification after correcting for inflammation in primary school children. The global view of the multiple criteria model as the gold standard for estimating ID is debatable and potentially impractical at a public health level. Current evidence cautions against overestimating the prevalence of ID, as there is more associated harm than deficiency underestimation. This critical analysis has confirmed a need for research to identify a suitable, accurate and precise alternative to Hb as a tool in the South African public health setting. Furthermore, the impact of inflammation on iron status indicators, in particular SF, should be assessed in context to clearly set parameters for its use in nationally-representative nutrition surveys, the cornerstone of iron intervention strategies. / MSc (Nutrition), North-West University, Potchefstroom Campus, 2015

Background The potential dire consequences of iron deficiency (ID) and iron deficiency anaemia (IDA) on childhood development are of major public health concern. Many factors contribute to anaemia, ID being only one progressive factor. The prevalence of ID and IDA must be accurately determined before iron intervention strategies can be safely prescribed. There is continued uncertainty regarding the optimal approach to identifying and measuring ID, as indicators have different roles, explore different aspects of iron metabolism and cannot be directly compared. Furthermore, inflammation and infection have a confounding effect on the commonly applied indicator and acute phase reactant, serum ferritin (SF). In the public health setting, a suitable method to assess iron status in developing countries has to be inexpensive, standardised, established, easy to measure and its applications specific to identifying ID. Aim We conducted secondary analysis of screening data from three independent iron intervention studies to critically evaluate the indicators used to determine iron status in 6-11-year-old primary school children from three South African provinces. Study design and methods A cross-sectional descriptive analysis was performed on the screening data collected in 2009 and 2010 during iron intervention studies in KwaZulu-Natal (n=736), Northern Cape (n= 1045), and North West (n=546). The three distinct study sites were analysed independently and collectively. Children’s haemoglobin (Hb), SF, transferrin receptor (TfR), zinc protoporphyrin (ZPP), and C-reactive protein (CRP) concentrations were measured and body iron calculated. ID prevalence was compared using different methods (namely the single indicators SF, TfR and ZPP, body iron and the multiple criteria model), and the influence of inflammation on SF was considered. Literature suggests that the multiple criteria model provides a more complete assessment of iron status. The performance of single and body iron indicators were compared to the multiple criteria model (by assessing sensitivity, specificity and predictive values). Results Significant positive correlations between CRP (indicator of inflammation) and SF existed in all study sites and the combined sample (p < 0.01). The mean SF concentration was substantially higher in subjects with inflammation than those without. A different SF cut-off to identify ID was applied to subjects with inflammation. The percentage of ID subjects varied using different indicators (4.2 – 26.5% in KwaZulu-Natal; 4.1 – 13.4% in Northern Cape; 7.0 – 24.4% in North West; and 5.4 – 15.2% in the combined sample). The sensitivity, specificity and predictive values of alternate ID indicators varied within and between study sites, compared to the multiple criteria model. Conclusion Simply using Hb as an ID indicator is inaccurate. The vast differences between percentages identified as ID by different indicators is reason for concern. No consistent agreement appeared between single ID indicators, body iron and the multiple criteria model for ID identification after correcting for inflammation in primary school children. The global view of the multiple criteria model as the gold standard for estimating ID is debatable and potentially impractical at a public health level. Current evidence cautions against overestimating the prevalence of ID, as there is more associated harm than deficiency underestimation. This critical analysis has confirmed a need for research to identify a suitable, accurate and precise alternative to Hb as a tool in the South African public health setting. Furthermore, the impact of inflammation on iron status indicators, in particular SF, should be assessed in context to clearly set parameters for its use in nationally-representative nutrition surveys, the cornerstone of iron intervention strategies. / MSc (Nutrition), North-West University, Potchefstroom Campus, 2015