Imbalance of Iron Availability and Demand in Patients With Acute and Chronic Heart Failure

BACKGROUND

Iron deficiency (ID) is a frequent comorbidity in patients with acute (AHF) and chronic heart failure (CHF) associated with morbidity and death. We aimed to better characterize iron homeostasis in patients with heart failure applying different biomarkers and to evaluate the accuracy of current ID definition by the European Society of Cardiology/American College of Cardiology/American Heart Association to indicate tissue iron availability and demand.

METHODS AND RESULTS

We performed a retrospective cohort study investigating 277 patients with AHF and 476 patients with CHF between February 2021 and May 2022. Patients with AHF had more advanced ID than patients with CHF, reflected by increased soluble transferrin receptor and soluble transferrin receptor-ferritin index, and lower ferritin, serum iron, transferrin saturation, hepcidin, and reticulocyte hemoglobin. Decreased iron availability or increased tissue iron demand, reflected by increased soluble transferrin receptor-ferritin index and decreased reticulocyte hemoglobin, was found in 84.1% (AHF) and 28.0% (CHF) with absolute ID and in 50.0% (AHF) and 10.5% (CHF) with combined ID according to the current European Society of Cardiology/American College of Cardiology/American Heart Association-based ID definition. Low hepcidin expression as an indicator of systemic ID was found in 91.1% (AHF) and 80.4% (CHF) of patients with absolute ID and in 32.3% (AHF) and 18.8% (CHF) of patients with combined ID. ID definitions with higher specificity reduce the need for iron supplementation by 25.5% in patients with AHF and by 65.6% in patients with CHF.

CONCLUSIONS

Our results suggest that the current European Society of Cardiology/American College of Cardiology/American Heart Association-based ID definition might overestimate true ID, particularly in CHF. More stringent thresholds for ID could more accurately identify patients with heart failure with reduced tissue iron availability who benefit from intravenous iron supplementation.

The effect of the flavonol rutin on serum and liver iron content in a genetic mouse model of iron overload

The flavonol rutin has been shown to possess antioxidant and iron chelating properties in vitro and in vivo. These dual properties are beneficial as therapeutic options to reduce iron accumulation and the generation of reactive oxygen species (ROS) resultant from excess free iron. The effect of rutin on iron metabolism has been limited to studies performed in wildtype mice either injected or fed high-iron diets. The effect of rutin on iron overload caused by genetic dysregulation of iron homoeostasis has not yet been investigated. In the present study we examined the effect of rutin treatment on tissue iron loading in a genetic mouse model of iron overload, which mirrors the iron loading associated with Type 3 hereditary haemochromatosis patients who have a defect in Transferrin Receptor 2 (TFR2). Male TFR2 knockout (KO) mice were administered rutin via oral gavage for 21 continuous days. Following treatment, iron levels in serum, liver, duodenum and spleen were assessed. In addition, hepatic ferritin protein levels were determined by Western blotting, and expression of iron homoeostasis genes by quantitative real-time PCR. Rutin treatment resulted in a significant reduction in hepatic ferritin protein expression and serum transferrin saturation. In addition, trends towards decreased iron levels in the liver and serum, and increased serum unsaturated iron binding capacity were observed. This is the first study to explore the utility of rutin as a potential iron chelator and therapeutic in an animal model of genetic iron overload.

Soluble Transferrin Receptor during infancy and reference intervals for the Roche Cobas platform

INTRODUCTION

Infant iron status assessments may be difficult to interpret due to infections. The soluble transferrin receptor (sTfR) has been suggested as a biomarker mainly unaffected by the acute phase response. Reference intervals reflecting dynamics of infant growth first year in life are not well established.

METHODS

The sTfR and CRP concentrations were measured in samples from 451 term infants with the Roche Cobas platform in umbilical cord, at 48-96 hours, 4 and 12 months. Reference values were constructed as the 2.5th and 97.5th percentiles. The relationship between CRP concentrations >1 mg/L and sTfR was tested by Kendall correlation.

RESULTS

Reference intervals for girls and boys were 2.4-9.5 mg/L at birth, 2.9-8.4 mg/L at 48-96 hours, 2.6-5.7 mg/L at 4 months and 3.0-6.3 mg/L at 12 months. No differences between sexes were observed except for at 4 months. sTfR did not covariate with CRP concentrations >1 mg/L except in 48-96 hours samples.

CONCLUSION

This study reports reference intervals for sTfR from birth to 12 months of age in a large group of infants in a low-risk area for iron deficiency. sTfR might add value to infant iron status diagnostics since no covariation with CRP was found at birth, at 4 months or at 12 months.

Hepcidin and other indicators of iron status, by alpha-1 acid glycoprotein levels, in a cohort of Mexican infants

The purpose of this study was to describe the changes in iron status indicators at 6 and 12 months of age, controlling by inflammation by measuring alpha-1 acid glycoprotein (AGP). This longitudinal study included 48 healthy-term singleton infants with birth weight ≥ 2500 g, born in hospitals of the Mexican Institute for Social Security. Complete blood count, ferritin, soluble transferrin receptor (sTfR), hepcidin, and AGP were measured in blood at 6 and 12 months of age. sTfR/ferritin ratio and total body iron (TBI) stores were calculated. Hemoglobin and sTfR/ferritin ratio increased with age, while ferritin and TBI decreased. In infants without inflammation, hepcidin, sTfR, and MVC did not show significant changes from 6 to 12 months of age, while ferritin and TBI decreased. In infants with inflammation, hepcidin, TBI, and ferritin levels increased, while hemoglobin and sTfR/ferritin ratio decreased. MVC and sTfR did not change significantly in the presence or absence of inflammation. Hepcidin concentration correlated positively and significantly with ferritin and TBI stores and showed significant negative correlation with sTfR/ferritin ratio. Our study showed that, in absence of inflammation and ID, during the first year of life, physiological changes occur in hemoglobin and ferritin levels as well as in indicators derived from ferritin and sTfR; in contrast, hepcidin and sTfR did not show significant change. However, hepcidin concentration was lower in infants with ID and was higher when inflammation was present, supporting that infants have a functional hepcidin response to changes in iron stores.

Iron metabolism and type 2 diabetes mellitus: A meta-analysis and systematic review

AIMS/INTRODUCTION

Iron metabolism can directly or indirectly affect the occurrence and development of type 2 diabetes. This meta-analysis and systematic review aimed to analyze the association between serum iron metabolism indicators and type 2 diabetes.

MATERIALS AND METHODS

The databases PubMed and Embase were searched for studies on the correlations between serum iron metabolism indicators (iron, ferritin, transferrin, hepcidin and soluble transferrin receptor) and type 2 diabetes since January 2006. Relevant data were extracted from the included studies, and meta-analysis was carried out.

RESULTS

A total of 12 case-control and cohort studies were analyzed. Of the 12 studies, 11 described the correlation between serum ferritin levels and type 2 diabetes. The median and high serum ferritin concentrations were significantly associated with the risks of type 2 diabetes (odds ratio [OR] 1.20, 95% confidence interval [CI] 1.08-1.33 and OR 1.43, 95% CI 1.29-1.59, respectively). However, the low concentration was not correlated with the risk of type 2 diabetes (OR 0.99, 95% CI 0.89-1.11). No significant association was observed between serum soluble transferrin receptor and type 2 diabetes, whereas the soluble transferrin receptor-to-ferritin ratio was significantly inversely related to the risk of type 2 diabetes in the median and high ratio subgroups (OR 0.71, 95% CI 0.51, 0.99 and OR 0.65, 95% CI 0.45-0.95).

CONCLUSIONS

The elevated serum ferritin was one of the risk factors for type 2 diabetes, and soluble transferrin receptor-to-ferritin ratio was inversely related to the risk of type 2 diabetes. A systematic review showed that serum transferrin and hepcidin might be directly or indirectly related to the development of diabetes.

Association between iron metabolism and cognitive impairment in older non-alcoholic fatty liver disease individuals: A cross-sectional study in patients from a Chinese center

Sparse is the research on the relationship between iron metabolism and mild cognitive impairment (MCI) in adults aged over 60 years with non-alcoholic fatty liver disease (NAFLD). The soluble transferrin receptor (sTfR), serum iron (SI), serum ferritin (SF), transferrin (TRF) and hemoglobin (HB) are indicators of iron metabolism.This study examined whether iron metabolism is associated with cognitive impairment in older individuals.A cross-sectional study was held in patients from a Chinese center. Individuals with NAFLD aged over 60 years were included if they did not have excessive alcohol intake and were free of stroke or dementia. Their cognitive function was assessed by the same neurologist. 3.0T H proton magnetic resonance spectroscopy (H-MRS) was performed to evaluate the hippocampus of the participants without contraindication. t test and Chi-square test were used to analyze the data. Binary logistic regression was used for correlation analysis.Fifty four (54%) of participants were diagnosed with MCI by the psychiatrist. MCI was significantly associated with higher sTfR after adjustment of all the covariates (OR = 2.565, 95%CI: 1.334∼4.934; P = .005). No statistically significant associations were observed between MCI and age or blood glucose or choline (Cho) /creatine (Cr) of theright hippocampus head.Increased age and low levels of sTfR and HB were associated with MCI in NAFLD individuals aged over 60 years.

Maternal iron-deficiency is associated with premature birth and higher birth weight despite routine antenatal iron supplementation in an urban South African setting: The NuPED prospective study

Background

Recent studies are suggesting a U-shaped relationship between antenatal iron exposure and birth outcomes. Little is known about the iron status and associated birth outcomes of pregnant women in South Africa. Our aim was to assess iron status at early, mid- and late pregnancy, and to determine associations with gestational age and birth weight in women in Johannesburg, South Africa.

Methods

In this prospective study of 250 pregnant women, we measured haemoglobin, biomarkers of iron status and inflammation at <18, 22 and 36 weeks of gestation, plus birth weight and gestational age at delivery. Associations of anaemia and iron status with birth outcomes were determined using regression models adjusted for confounders.

Results

At enrolment, the prevalence of anaemia, iron depletion (ID) and iron deficiency erythropoiesis (IDE) was 29%, 15% and 15%, respectively, and increased significantly with pregnancy progression. Anaemia and ID at 22 weeks, as well as IDE at 36 weeks were associated with higher birth weight (β = 135.4; 95% CI: 4.8, 266.1 and β = 205.4; 95% CI: 45.6, 365.1 and β = 178.0; 95% CI: 47.3, 308.7, respectively). Women in the lowest ferritin quartile at 22 weeks gave birth to babies weighing 312 g (95% CI: 94.8, 528.8) more than those in the highest quartile. In contrast, IDE at 22 weeks was associated with a higher risk for premature birth (OR: 3.57, 95% CI: 1.24, 10.34) and women in lower haemoglobin quartiles at <18 weeks had a shorter gestation by 7 days (β = -6.9, 95% CI: -13.3, -0.6) compared to those in the highest quartile.

Conclusion

Anaemia, ID and IDE prevalence increased during pregnancy despite routine iron supplementation. ID and anaemia at mid-pregnancy were associated with higher birth weight, while IDE was associated with premature birth. These results suggest that current antenatal screening and supplementation practices in South Africa need to be revisited.

The effect of donation activity dwarfs the effect of lifestyle, diet and targeted iron supplementation on blood donor iron stores

The iron status of blood donors is a subject of concern for blood establishments. The Finnish Red Cross Blood Service addresses iron loss in blood donors by proposing systematic iron supplementation for demographic at-risk donor groups. We measured blood count, ferritin and soluble transferrin receptor (sTfR) and acquired lifestyle and health information from 2200 blood donors of the FinDonor 10000 cohort. We used modern data analysis methods to estimate iron status and factors affecting it with a special focus on the effects of the blood service's iron supplementation policy. Low ferritin (< 15 μg/L), an indicator of low iron stores, was present in 20.6% of pre-menopausal women, 10.6% of post-menopausal women and 6% of men. Anemia co-occurred with iron deficiency more frequently in pre-menopausal women (21 out of 25 cases) than in men (3/6) or post-menopausal women (1/2). In multivariable regression analyses, lifestyle, dietary, and blood donation factors explained up to 38% of the variance in ferritin levels but only ~10% of the variance in sTfR levels. Days since previous donation were positively associated with ferritin levels in all groups while the number of donations during the past 2 years was negatively associated with ferritin levels in pre-menopausal women and men. FRCBS-provided iron supplementation was negatively associated with ferritin levels in men only. Relative importance analyses showed that donation activity accounted for most of the explained variance in ferritin levels while iron supplementation explained less than 1%. Variation in ferritin levels was not significantly associated with variation in self-reported health. Donation activity was the most important factor affecting blood donor iron levels, far ahead of e.g. red-meat consumption or iron supplementation. Importantly, self-reported health of donors with lower iron stores was not lower than self-reported health of donors with higher iron stores.

Markers of iron status, blood pressure and incident hypertension among Chinese adults

BACKGROUND AND AIMS

The evidence on the relationship between markers of iron, blood pressure and hypertension are limited and inconsistent. This prospective cohort study aimed to investigate the relationship of serum ferritin (SF), transferrin, soluble transferrin receptor (sTFR) and haemoglobin on blood pressure and incident hypertension in the China Health and Nutrition Survey (CHNS) study.

METHODS AND RESULTS

We studied 8337 adults aged 18 years old or above from CHNS in 2009 to investigate the association of markers of iron and blood pressure (BP). Among them, 4509 non-hypertensive participants who completed follow up were included to investigate the association of markers of iron and hypertension development. Linear regression model was used to assess the association between markers of iron and BP. Cox regression model was used to examine the association of markers of iron and hypertension development. SF and serum sTFR concentration had a non-significant effect on incident hypertension. Transferrin and haemoglobin concentrations were positively associated with incident hypertension. Compared to the participants with the lowest tertile of transferrin, those with the highest tertile had a higher risk of developing hypertension [HR: 1.26, 95% CI (1.04, 1.53), P = 0.017]. Similarly, participants with the highest tertile of haemoglobin had a significantly higher risk of incident hypertension [HR: 1.27, 95% CI (1.01, 1.59), P = 0.038].

CONCLUSION

The current study found that haemoglobin and transferrin levels were positively associated with blood pressure and incident hypertension. Further research in different ethnic groups is required to confirm the association of the full range of markers of iron with BP and incident hypertension.

[Association between the polymorphisms of TMPRSS6 and the levels of serum ferrtin and soluble transferrin receptor in pregnant women in Lüliang Area of Shanxi Province]

OBJECTIVE

To analysis the associations between the polymorphisms of TMPRSS6 and the levels of serum ferritin( SF) and soluble transferrin receptor( s TfR) in pregnant women.

METHODS

A total of 807 pregnant women were recruited by using cluster random sampling method from Lüliang in Shanxi Province in 2014. Roche Tinaquant immunoturbidimetric assay was used to measure the level of SF and s TfR, then iron deficiency( ID) was identified by the criteria of SF < 25 ng/m L and s TfR > 4. 4 mg/L, respectively. Sequenom MassArray was used to genotype the 7 targeted single-nucleotide polymorphisms( SNPs)( rs11704654, rs1421312, rs2111833, rs2235321, rs2543519, rs4820268 and rs855791) of the subjects. The t test and ANOVA analysis were used to test the different levels of SF and s TfR among SNPs, and chi-square test and Logistic regression were conducted to detect the associations between genotypes of each locus and ID.

RESULTS

The differences of the levels of Ln SF between genotypes in rs2111833 were significant( F = 3. 57, P = 0. 0287), and the Ln SF level of T allele carrier group was lower than CC group( t = 2. 03, P = 0. 0429). The Ln SF level of A allele carrier group was lower than GG carrier group in rs855791( t = 1. 97, P = 0. 0490). For rs11704654, the ratio of SF < 25 ng/m L of T allele carriers was higher than CC carriers( χ~2= 4. 5456, P = 0. 0330). For rs211183, the ratio of SF < 25 ng/m L of T allele carriers was higher than CC carriers( χ~2= 4. 6431, P = 0. 0312). For rs855791, the ratio of SF < 25 ng/m L of GG carriers was lower than A allele carriers( χ~2= 5. 0134, P = 0. 0263). rs11704654( T) and rs855791( A) were still shown the association with SF < 25 ng/m L status in logistic analysis adjusted by age and gestational weeks. The Ln s TfR level of T allele carrier group in rs11704654 was higher than CC carrier group( t =-2. 012, P = 0. 024), and the Ln s TfR level of G allele carrier group in rs2543519 was higher than AA carrier group( t =-1. 954, P = 0. 011).

CONCLUSION

The associations between polymorphisms of TMPRSS6 and the levels of SF and s TfR are observed in pregnant women.

Anemia and Iron Status Among Different Body Size Phenotypes in Chinese Adult Population: a Nation-Wide, Health and Nutrition Survey

Previous studies have shown that there is a controversial relationship between iron homeostasis and obesity. This study aims to explore the relationship of anemia and iron status with different body size phenotypes in adult Chinese population. Using information on iron status-related parameters and lifestyle data from 8462 participants of the 2009 wave of China Health and Nutrition Survey (2009 CHNS), we performed multivariable logistic regression analyses to estimate the odds ratios (ORs) for the risk of anemia and iron parameters according to different body size phenotypes. Participants with higher body mass index (BMI) had a lower anemia prevalence with significant trends in both metabolic status groups (P < 0.001). Serum ferritin, transferrin, and soluble transferrin receptor (sTfR)/log ferritin index were significant in different metabolic status groups and in different body size phenotypes, respectively. The ORs for higher ferritin and transferrin increased across different body size phenotypes in both genders, and for sTfR/log ferritin index decreased (P < 0.01 for trend). This association was still statistically significant after adjustment for multiple confounders. We found an inverse association of BMI levels with the prevalence of anemia and strong association of serum ferritin and transferrin with higher risk of obesity or overweight in both metabolic status groups.

Carnosine supplementation reduces plasma soluble transferrin receptor in healthy overweight or obese individuals: a pilot randomised trial

Abnormalities of iron homeostasis have been linked to insulin resistance, type 2 diabetes and cardiovascular disease. Carnosine, an over-the-counter food supplement with chelating properties, has been shown to decrease serum iron and improve glucose metabolism in diabetic rodents. We have previously demonstrated that carnosine supplementation prevented worsening of glucose metabolism in healthy overweight and obese middle-aged adults. Yet, the impact of carnosine on markers of iron metabolism in humans has not been investigated. We aimed to determine whether carnosine supplementation has an effect on iron parameters in overweight and obese, otherwise healthy adults. We included 26 participants, who were randomly allocated to receive 1 g carnosine (n = 14) or identical placebo (n = 12) twice daily for 12 weeks. Iron parameters including iron, ferritin, transferrin, soluble transferrin receptor, total iron binding capacity and iron saturation were measured in serum or plasma by standard commercial assays. Carnosine supplementation decreased plasma soluble transferrin receptor compared to placebo (mean change difference ± standard error: - 0.07 ± 0.03 mg/l, p = 0.04). None of the other iron parameters were different between carnosine and placebo groups. At follow-up, soluble transferrin receptor was associated inversely with urinary carnosine concentrations and positively with serum carnosinase-1 activity (both p < 0.02). Our findings suggest that carnosine may modulate iron metabolism in high-risk groups which could ameliorate insulin resistance and prevent type 2 diabetes. Larger human clinical trials are required to confirm our results.

Hepcidin, soluble transferrin receptor and IL-6 levels in obese children and adolescents with and without type 2 diabetes mellitus/impaired glucose tolerance and their association with obstructive sleep apnea

PURPOSE

Obesity, type 2 diabetes mellitus (T2DM), and obstructive sleep apnea (OSA) are associated with chronic low-grade inflammation. Iron metabolism is linked with insulin-resistant states and with OSA in adults. The association of body iron status with T2DM in children remains undefined. We aimed to evaluate plasma interleukin-6 (IL-6), hepcidin, and soluble transferrin receptor (sTfR) levels in obese patients with T2DM or impaired glucose tolerance (IGT) and in those without, and the contribution of OSA to their levels.

METHODS

In this cross-sectional study, obese children and adolescents with and without T2DM/IGT underwent overnight polysomnography. Fasting plasma concentrations of IL-6, hepcidin, and sTfR were measured and evaluated according to glycemic status (T2DM/IGT and normal glucose tolerance) and the presence of OSA.

RESULTS

Ten patients with T2DM (age 15.9 ± 3.6 years), 8 with IGT (age 13.1 ± 2.5 years) and 20 subjects with normal glucose tolerance matched for body mass index standard deviation score (age 12.6 ± 3.3 years) were studied. Sleep measures or IL-6, hepcidin, and sTfR levels were not significantly different between the group with T2DM/IGT vs. the control group. No significant differences were found in hepcidin or sTfR levels between patients with OSA and those without. However, patients with OSA showed higher plasma IL-6 values compared with those without (4.56 ± 2.92 vs. 2.83 ± 1.54 pg/ml, P = 0.025), and the highest values were evident in patients affected by both T2DM/IGT and OSA.

CONCLUSIONS

Higher IL-6 levels were associated with both glycemic status and OSA. No differences in body iron regulator levels were found in obese patients with T2DM/IGT compared to those without or in those with OSA compared to those without. Further longitudinal studies in larger population samples are warranted.

Relationships between Maternal Obesity and Maternal and Neonatal Iron Status

Obesity in pregnancy may negatively influence maternal and infant iron status. The aim of this study was to examine the association of obesity with inflammatory and iron status in both mother and infant in two prospective studies in pregnancy: UPBEAT and SCOPE. Maternal blood samples from obese (n = 245, BMI ≥ 30 kg/m²) and normal weight (n = 245, BMI < 25 kg/m²) age matched pregnant women collected at approximately 15 weeks’ gestation, and umbilical cord blood samples collected at delivery, were analysed for a range of inflammatory and iron status biomarkers. Concentrations of C- reactive protein and Interleukin-6 in obese women compared to normal weight women were indicative of an inflammatory response. Soluble transferrin receptor (sTfR) concentration [18.37 nmol/L (SD 5.65) vs. 13.15 nmol/L (SD 2.33)] and the ratio of sTfR and serum ferritin [1.03 (SD 0.56) vs. 0.69 (SD 0.23)] were significantly higher in obese women compared to normal weight women (P < 0.001). Women from ethnic minority groups (n = 64) had higher sTfR concentration compared with white women. There was no difference in maternal hepcidin between obese and normal weight women. Iron status determined by cord ferritin was not statistically different in neonates born to obese women compared with neonates born to normal weight women when adjusted for potential confounding variables. Obesity is negatively associated with markers of maternal iron status, with ethnic minority women having poorer iron statuses than white women.

[Biological diagnosis of iron deficiency in children]

Measurement of serum ferritin (SF) is currently the laboratory test recommended for diagnosing iron deficiency. In the absence of an associated disease, a low SF value is an early and highly specific indicator of iron deficiency. The WHO criteria proposed to define depleted storage iron are 12μg/L for children under 5 years and 15μg/L for those over 5 years. A higher threshold of 30μg/L is used in the presence of infection or inflammation. Iron deficiency anemia, with typical low mean corpuscular volume and mean corpuscular hemoglobin, is only present at the end stage of iron deficiency. Other diagnostic tests for iron deficiency including iron parameters (low serum iron, increased total iron-binding capacity, low transferrin saturation) and erythrocyte traits (low mean corpuscular volume, increased zinc protoporphyrin) provide little additional diagnostic value over SF. In children, serum soluble transferrin receptor (sTfR) has been reported to be a sensitive indicator of iron deficiency and is relatively unaffected by inflammation. On the other hand, sTfR is directly related to extent of erythroid activity and not commonly used in clinical practice. In population surveys, approaches based on combinations of markers have been explored to improve the specificity and sensitivity of diagnostic. In addition to Hb value determination, a combination of parameters (among transferrin saturation, zinc protoporphyrin, mean corpuscular volume or serum ferritin) was generally used to assess iron deficiency. More recently sTfR/ ferritin index were evaluated, sTfR in conjunction with SF allowing to better distinguishing iron deficiency from inflammatory anemia. Also, hepcidin measurements appeared an interesting marker for diagnosing iron deficiency and identifying individuals in need of iron supplementation in populations where inflammatory or infectious diseases are frequently encountered. Reticulocyte Hb content (CHr) determination is an early parameter of iron deficiency erythropoiesis. CHr can be measured with several automated hematology analyzers and so, used for individual's iron status assessment. In addition to Hb concentration determination, individual's iron status is commonly assessed in the pediatric clinical practice by the SF measurement accompanied by the determination of C-reactive protein for detection of a simultaneous acute infection and/or inflammation.

Rational Management of Iron-Deficiency Anaemia in Inflammatory Bowel Disease

Anaemia is the most frequent, though often neglected, comorbidity of inflammatory bowel disease (IBD). Here we want to briefly present (1) the burden of anaemia in IBD, (2) its pathophysiology, which mostly arises from bleeding-associated iron deficiency, followed by (3) diagnostic evaluation of anaemia, (4) a balanced overview of the different modes of iron replacement therapy, (5) evidence for their therapeutic efficacy and subsequently, (6) an updated recommendation for the practical management of anaemia in IBD. Following the introduction of various intravenous iron preparations over the last decade, questions persist about when to use these preparations as opposed to traditional and other novel oral iron therapeutic agents. At present, oral iron therapy is generally preferred for patients with quiescent IBD and mild iron-deficiency anaemia. However, in patients with flaring IBD that hampers intestinal iron absorption and in those with inadequate responses to or side effects with oral preparations, intravenous iron supplementation is the therapy of choice, although information on the efficacy of intravenous iron in patients with active IBD and anaemia is scare. Importantly, anaemia in IBD is often multifactorial and a careful diagnostic workup is mandatory for optimized treatment. Nevertheless, limited information is available on optimal therapeutic start and end points for treatment of anaemia. Of note, neither oral nor intravenous therapies seem to exacerbate the clinical course of IBD. However, additional prospective studies are still warranted to determine the optimal therapy in complex conditions such as IBD.

Harmonization of blood-based indicators of iron status: making the hard work matter

Blood-based indicators that are used in the assessment of iron status are assumed to be accurate. In practice, inaccuracies in these measurements exist and stem from bias and variability. For example, the analytic variability of serum ferritin measurements across laboratories is very high (>15%), which increases the rate of misclassification in clinical and epidemiologic studies. The procedures that are used in laboratory medicine to minimize bias and variability could be used effectively in clinical research studies, particularly in the evaluation of iron deficiency and its associated anemia in pregnancy and early childhood and in characterizing states of iron repletion and excess. The harmonization and standardization of traditional and novel bioindicators of iron status will allow results from clinical studies to be more meaningfully translated into clinical practice by providing a firm foundation for clinical laboratories to set appropriate cutoffs. In addition, proficiency testing monitors the performance of the methods over time. It is important that measures of iron status be evaluated, validated, and performed in a manner that is consistent with standard procedures in laboratory medicine.

Serum Hepcidin and Soluble Transferrin Receptor in the Assessment of Iron Metabolism in Children on a Vegetarian Diet

The aim of this study was to assess the effect of vegetarian diet on iron metabolism parameters paying special attention to serum hepcidin and soluble transferrin receptor (sTfR) concentrations in 43 prepubertal children (age range 4.5-9.0 years) on vegetarian and in 46 children on omnivorous diets. There were no significant differences according to age, weight, height, and body mass index (BMI) between vegetarian and omnivorous children. Vegetarians had similar intake of iron and vitamin B₁₂ and a significantly higher intake of vitamin C (p < 0.05) compared with non-vegetarians. Hematologic parameters and serum iron concentrations were within the reference range in both groups of children. Serum transferrin levels were similar in all subjects; however, ferritin concentrations were significantly (p < 0.01) lower in vegetarians than in omnivores. In children on a vegetarian diet, median hepcidin levels were lower (p < 0.05) but sTfR concentrations significantly higher (p < 0.001) compared with omnivorous children. In the multivariate regression model, we observed associations between hepcidin level and ferritin concentration (β = 0.241, p = 0.05) in the whole group of children as well as between hepcidin concentration and CRP level (β = 0.419, p = 0.047) in vegetarians. We did not find significant associations with concentration of sTfR and selected biochemical, anthropometric, and dietary parameters in any of the studied groups of children. As hematologic parameters and iron concentrations in vegetarians and omnivores were comparable and ferritin level was lower in vegetarians, we suggest that inclusion of novel markers, in particular sTfR (not cofounded by inflammation) and hepcidin, can better detect subclinical iron deficiency in children following vegetarian diets.

Assessment of iron status in settings of inflammation: challenges and potential approaches

The determination of iron status is challenging when concomitant infection and inflammation are present because of confounding effects of the acute-phase response on the interpretation of most iron indicators. This review summarizes the effects of inflammation on indicators of iron status and assesses the impact of a regression analysis to adjust for inflammation on estimates of iron deficiency (ID) in low- and high-infection-burden settings. We overviewed cross-sectional data from 16 surveys for preschool children (PSC) (n = 29,765) and from 10 surveys for nonpregnant women of reproductive age (WRA) (n = 25,731) from the Biomarkers Reflecting the Inflammation and Nutritional Determinants of Anemia (BRINDA) project. Effects of C-reactive protein (CRP) and α1-acid glycoprotein (AGP) concentrations on estimates of ID according to serum ferritin (SF) (used generically to include plasma ferritin), soluble transferrin receptor (sTfR), and total body iron (TBI) were summarized in relation to infection burden (in the United States compared with other countries) and population group (PSC compared with WRA). Effects of the concentrations of CRP and AGP on SF, sTfR, and TBI were generally linear, especially in PSC. Overall, regression correction changed the estimated prevalence of ID in PSC by a median of +25 percentage points (pps) when SF concentrations were used, by -15 pps when sTfR concentrations were used, and by +14 pps when TBI was used; the estimated prevalence of ID in WRA changed by a median of +8 pps when SF concentrations were used, by -10 pps when sTfR concentrations were used, and by +3 pps when TBI was used. In the United States, inflammation correction was done only for CRP concentrations because AGP concentrations were not measured; regression correction for CRP concentrations increased the estimated prevalence of ID when SF concentrations were used by 3 pps in PSC and by 7 pps in WRA. The correction of iron-status indicators for inflammation with the use of regression correction appears to substantially change estimates of ID prevalence in low- and high-infection-burden countries. More research is needed to determine the validity of inflammation-corrected estimates, their dependence on the etiology of inflammation, and their applicability to individual iron-status assessment in clinical settings.

Serum ferritin as an indicator of iron status: what do we need to know?

Determination of iron status in pregnancy and in young children is essential for both clinical and public health practice. Clinical diagnosis of iron deficiency (ID) through sampling of bone marrow to identify the absence of body iron stores is impractical in most cases. Serum ferritin (SF) concentrations are the most commonly deployed indicator for determining ID, and low SF concentrations reflect a state of iron depletion. However, there is considerable variation in SF cutoffs recommended by different expert groups to diagnose ID. Moreover, the cutoffs used in different clinical laboratories are heterogeneous. There are few studies of diagnostic test accuracy to establish the sensitivity and specificity of SF compared with key gold standards (such as absent bone marrow iron stores, increased intestinal iron absorption, and hemoglobin response to SF) among noninflamed, outpatient populations. The limited data available suggest the commonly recommended SF cutoff of <15 μg/L is a specific but not sensitive cutoff, although evidence is limited. Data from women during pregnancy or from young children are especially uncommon. Most data are from studies conducted >30 y ago, do not reflect ethnic or geographic diversity, and were performed in an era for which laboratory methods no longer reflect present practice. Future studies to define the appropriate SF cutoffs are urgently needed and would also provide an opportunity to compare this indicator with other established and emerging iron indexes. In addition, future work would benefit from a focus on elucidating cutoffs and indexes relevant to iron adequacy.

Laboratory methodologies for indicators of iron status: strengths, limitations, and analytical challenges

Biochemical assessment of iron status relies on serum-based indicators, such as serum ferritin (SF), transferrin saturation, and soluble transferrin receptor (sTfR), as well as erythrocyte protoporphyrin. These indicators present challenges for clinical practice and national nutrition surveys, and often iron status interpretation is based on the combination of several indicators. The diagnosis of iron deficiency (ID) through SF concentration, the most commonly used indicator, is complicated by concomitant inflammation. sTfR concentration is an indicator of functional ID that is not an acute-phase reactant, but challenges in its interpretation arise because of the lack of assay standardization, common reference ranges, and common cutoffs. It is unclear which indicators are best suited to assess excess iron status. The value of hepcidin, non-transferrin-bound iron, and reticulocyte indexes is being explored in research settings. Serum-based indicators are generally measured on fully automated clinical analyzers available in most hospitals. Although international reference materials have been available for years, the standardization of immunoassays is complicated by the heterogeneity of antibodies used and the absence of physicochemical reference methods to establish "true" concentrations. From 1988 to 2006, the assessment of iron status in NHANES was based on the multi-indicator ferritin model. However, the model did not indicate the severity of ID and produced categorical estimates. More recently, iron status assessment in NHANES has used the total body iron stores (TBI) model, in which the log ratio of sTfR to SF is assessed. Together, sTfR and SF concentrations cover the full range of iron status. The TBI model better predicts the absence of bone marrow iron than SF concentration alone, and TBI can be analyzed as a continuous variable. Additional consideration of methodologies, interpretation of indicators, and analytic standardization is important for further improvements in iron status assessment.

Iron status and anaemia in Sri Lankan secondary school children: A cross-sectional survey

BACKGROUND

Iron deficiency, the most common micronutrient disorder and cause of anaemia globally, impairs growth, cognition, behaviour and resistance to infection.

METHODS/RESULTS

As part of a national survey of inherited haemoglobin variants in 7526 students from 72 secondary schools purposefully selected from the 25 districts of Sri Lanka, we studied 5912 students with a normal haemoglobin genotype. Median age was 16.0 (IQR 15.0-17.0) years and 3189 (53.9%) students were males. Most students were Sinhalese (65.7%), with fewer Tamils (23.1%) and Muslims (11.2%). Anaemia occurred in 470 students and was more common in females (11.1%) than males (5.6%). Haemoglobin, serum ferritin, transferrin receptor and iron were determined in 1196 students with low red cell indices and a structured sample of those with normal red cell indices (n = 513). The findings were weighted to estimate the frequencies of iron deficiency and iron deficiency anaemia classified according to WHO criteria. Iron depletion (serum ferritin <15ug/ml) occurred in 19.2% and cellular iron deficiency (low serum ferritin and transferrin receptor >28.1 nmol/l) in 11.6% students. Iron deficiency anaemia (cellular iron deficiency with low haemoglobin) occurred in only 130/2794 (4.6%) females and 28/2789 (1.0%) males. Iron biomarkers were normal in 83/470 (14.6%) students with anaemia. In multiple regression analysis, the odds for iron depletion and cellular iron deficiency were about one-third in males compared with females, and the odds for iron deficiency anaemia were about one fifth in males compared to females. Tamil ethnicity and age <16 years increased the risk of all three stages of iron deficiency and living at high altitude significantly reduced the risk of iron depletion.

CONCLUSIONS

Low iron status and anaemia remain common problems in Sri Lankan secondary school students especially females, younger students and the socioeconomically disadvantaged Tamil population. More research is needed to identify factors other than low iron status that contribute to anaemia in adolescents.

Effect of iron and zinc-biofortified pearl millet consumption on growth and immune competence in children aged 12-18 months in India: study protocol for a randomised controlled trial

INTRODUCTION

Biofortified crops represent a sustainable agricultural solution for the widespread micronutrient malnutrition in India and other resource-limited settings. This study aims to investigate the effect of the consumption of foods prepared with iron- and zinc-biofortified pearl millet (FeZn-PM) by children on biomarkers of iron and zinc status, growth, and immune function.

METHODS AND ANALYSIS

We will conduct a randomised controlled feeding trial in identified slums of Mumbai, India among 200 children aged between 12 and 18 months. Children will be randomised to receive foods prepared with the biofortified PM (FeZn-PM, ICTP8203-Fe) or non-biofortified PM. Anthropometric and morbidity data will be gathered every month for 9 months. Biological samples will be collected at baseline, midline and endline to assess iron and zinc status, including haemoglobin, serum ferritin, serum transferrin receptor, serum zinc, C-reactive protein and alpha-1 acid glycoprotein. Biological samples will be archived for future analyses. The midline measurement will be a random serial sample between baseline and endline. Immune function will be assessed at each time point by the measurement of T cell counts and vaccine responses in a subset, respectively.

ETHICS AND DISSEMINATION

This study has obtained clearance from the Health Ministry Screening Committee of the Indian Council of Medical Research. Ethical clearance has been obtained from Cornell University's Institutional Review Board, the Inter System Biomedica Ethics Committee and St John's Research Institute's Institutional Ethics Review Board. The results of this study will be disseminated at several research conferences and as published articles in peer-reviewed journals.

TRIAL REGISTRATION NUMBER

Clinical trial registration number NCT02233764. CTRI registration number REF/2014/10/007731.

Iron deficiency was not the major cause of anemia in rural women of reproductive age in Sidama zone, southern Ethiopia: A cross-sectional study

Background

Anemia, which has many etiologies, is a moderate/severe public health problem in young children and women of reproductive age in many developing countries. The aim of this study was to investigate prevalence of iron deficiency, anemia, and iron deficiency anemia using multiple biomarkers and to evaluate their association with food insecurity and food consumption patterns in non-pregnant women from a rural area of southern Ethiopia.

Methods

A cross-sectional study was conducted in 202 rural women of reproductive age in southern Ethiopia. Anthropometrics and socio-demographic data were collected. A venipuncture blood sample was analyzed for hemoglobin (Hb) and for biomarkers of iron status. Biomarkers were skewed and were log transformed before analysis. Mean, median, Pearson’s correlations and ordinary least-squares regressions were calculated.

Results

Median (IQR) Hb was 138 (127, 151) g/L. Based on an altitude-adjusted (1708 m) cutoff of 125 g/L for Hb, 21.3% were anemic. Plasma ferritin was <15 μg/L in 18.6% of the women. Only one woman had α-1-acid glycoprotein (AGP) >1.0 g/L; four women (2%) had > 5 mg/L of C-reactive protein (CRP). Of the 43 women who were anemic, 23.3% (10 women) had depleted iron stores based on plasma ferritin. Three of these had elevated soluble transferrin receptors (sTfR). Hemoglobin (Hb) concentration was negatively correlated with sTfR (r = -0.24, p = 0.001), and positively correlated with ferritin (r = 0.17, p = 0.018), plasma iron (r = 0.15, p = 0.046), transferrin saturation (TfS) (r = 0.15, p = 0.04) and body iron (r = 0.14, p = 0.05). Overall prevalence of iron deficiency anemia was only 5%.

Conclusion

Iron deficiency anemia was not prevalent in the study population, despite the fact that anemia would be classified as a moderate public health problem.

Stages of chronic kidney disease and soluble Transferrin Receptor (sTfR), Ferritin, ratio

OBJECTIVE

To assess the ratio of soluble transferrin receptor to ferritin in different stages of chronic kidney disease.

METHODS

This case-control study was conducted at the Aga Khan University Hospital and the Jinnah Postgraduate Medical Centre, Karachi, from January to September 2014, and comprised chronic kidney disease patients and healthy controls. Group 1 comprised controls, whereas groups 2, 3 and 4 had patients based on their mean glomerular filtration rate. SPSS 19 was used for data analysis.

RESULTS

Of the 170 participants, 126(74.1%) were cases and 44(25.9%) were controls. The overall mean age was 55.87±3.48 years and the mean body mass index was 24.25±2.9 kg/m2. Decreased levels of iron and haemoglobin were observed in cases compared to controls (p<0.001), while high serum ferritin was seen in cases compared to the controls (p<0.001). Correspondingly, the soluble transferrin receptor-to-ferritin ratio was significantly decreased in groups 2, 3 and 4 (p<0.001).

CONCLUSIONS

The ratio of soluble transferrin receptor to ferritin was lower in higher stages of chronic kidney disease.

Is Erythrocyte Protoporphyrin a Better Single Screening Test for Iron Deficiency Compared to Hemoglobin or Mean Cell Volume in Children and Women?

Hemoglobin (Hb), mean cell volume (MCV), and erythrocyte protoporphyrin (EP) are commonly used to screen for iron deficiency (ID), but systematic evaluation of the sensitivity and specificity of these tests is limited. The objective of this study is to determine the sensitivity and specificity of Hb, MCV, and EP measurements in screening for ID in preschool children, non-pregnant women 15-49 years of age, and pregnant women. Data from the National Health and Nutrition Examination Surveys (NHANES) (NHANES 2003-2006: n = 861, children three to five years of age; n = 3112, non-pregnant women 15 to 49 years of age. NHANES 1999-2006: n = 1150, pregnant women) were examined for this purpose. Children or women with blood lead ≥10 µg/dL or C-reactive protein (CRP) >5.0 mg/L were excluded. ID was defined as total body iron stores <0 mg/kg body weight, calculated from the ratio of soluble transferrin receptor (sTfR) to serum ferritin (SF). The receiver operating characteristic (ROC) curve was used to characterize the sensitivity and specificity of Hb, MCV, and EP measurements in screening for ID. In detecting ID in children three to five years of age, EP (Area under the Curve (AUC) 0.80) was superior to Hb (AUC 0.62) (p < 0.01) but not statistically different from MCV (AUC 0.73). In women, EP and Hb were comparable (non-pregnant AUC 0.86 and 0.84, respectively; pregnant 0.77 and 0.74, respectively), and both were better than MCV (non-pregnant AUC 0.80; pregnant 0.70) (p < 0.01). We concluded that the sensitivity and specificity of EP in screening for ID were consistently superior to or at least as effective as those of Hb and MCV in each population examined. For children three to five years of age, EP screening for ID was significantly better than Hb and similar to MCV. For both non-pregnant and pregnant women, the performance of EP and Hb were comparable; both were significantly superior to MCV.

Evaluation of the Efficiency of the Reticulocyte Hemoglobin Content on Diagnosis for Iron Deficiency Anemia in Chinese Adults

Our aim was to evaluate the cut-off value and efficiency of using reticulocyte hemoglobin content as a marker to diagnose iron deficiency anemia in Chinese adults. 140 adults who needed bone marrow aspiration for diagnosis at the hematology department of the Peking Union Medical College Hospital were enrolled according to the inclusive and exclusive criteria. Venous blood samples were collected to detect complete blood count, including hemoglobin, reticulocyte hemoglobin content, hematocrit, mean cellular volume, corpuscular hemoglobin concentration, hemoglobin content, free erythrocyte protoporphyrin; iron indexes of serum ferritin, serum transferrin receptor, and unsaturated iron-binding capacity; and inflammation markers of C-reactive protein and α-acid glycoprotein. Bone marrow samples were obtained for the bone marrow iron staining, which was used as the standard for the evaluation of iron status in this study. Subjects were divided into three groups according to hemoglobin levels and bone marrow iron staining results: the IDA (iron deficiency anemia) group, the NIDA (non-iron deficiency anemia) group, and the control group. The differences of the above-mentioned indexes were compared among the three groups and the effect of inflammation was also considered. The cut-off value of reticulocyte hemoglobin content was determined by receiver operation curves. The IDA group (n = 56) had significantly lower reticulocyte hemoglobin content, mean cellular volume, corpuscular hemoglobin concentration, hemoglobin content, and serum ferritin; and higher free erythrocyte protoporphyrin, unsaturated iron-binding capacity, and serum transferrin receptor (p < 0.05) compared with the NIDA group (n = 38) and control group (n = 46). Hematocrit, serum ferritin, and unsaturated iron-binding capacity were significantly affected by inflammation while reticulocyte hemoglobin content and other parameters were not. The cut-off value of reticulocyte hemoglobin content for diagnosing iron deficiency anemia was 27.2 pg, with a sensitivity of 87.5% and a specificity of 92.9%. The cut-off values for mean cellular volume, serum ferritin, and serum transferrin receptor were 76.6, 12.9, and 4.89 mg/L, respectively. Reticulocyte hemoglobin content had the largest area under the curve of 0.929, while those for mean cellular volume, serum ferritin, serum transferrin receptor were 0.922, 0.887, and 0.900, respectively. Reticulocyte hemoglobin content has a high sensitivity and specificity in the diagnosis of iron deficiency anemia, and its comprehensive diagnostic efficacy is better than other traditional indicators-such as serum ferritin and serum transferrin receptor.

Anaemia control and the interpretation of biochemical tests for iron status in children

BACKGROUND

Anaemia is one of the world's most prevalent child health problems. Its control in Africa and other developing nations has been hindered by uncertainty regarding its cause. Anaemia control has been particularly problematic in regions where the non-iron deficiency causes of anaemia, are projected to be substantial. The implementation of effective interventions to reduce the anaemia prevalence, requires improved documentation on iron status and other causes of anaemia for target populations.

METHODS

This cross-sectional study enrolled n = 184 children, aged 6-8 years from Kwazulu-Natal, South Africa. Tests of haemoglobin, serum ferritin, soluble transferrin receptor and C-reactive protein were performed. These conventional measures of iron status were used to calculate body iron and to categorize the children into different groups of anaemia profiles.

RESULTS

Anaemia prevalence was high, 43/184 (23.4%). Iron deficiency anaemia contributed 7/43 (16.3%) to the anaemia prevalence compared to non-iron deficiency anaemia 34/43 (79.1%) and mixed anaemia 2/43 (4.7%). In total 47/184 (25.5%) of the sampled children had either iron deficiency or anaemia. Information about the presence of inflammation was used to adjust serum ferritin concentrations, resulting in improved diagnosis of iron deficiency.

CONCLUSION

Appropriate investigations for iron status and inflammation/infection screening, need to be integral in the evaluation of anaemia and its causes before anaemia control interventions are implemented. Interventions that target the multifactorial nature of anaemia in school-aged children need to be strengthened. Additionally, regular screening of anaemia in school-aged children from disadvantaged communities is recommended.

TFR2-related haemochromatosis in the Netherlands: a cause of arthralgia in young adulthood

BACKGROUND

Type 3 hereditary haemochromatosis (HH) is a rare iron overload disorder caused by variants in the transferrin 2 receptor (TFR2) gene. We aim to present characteristics of patients diagnosed with TFR2-HH in the Netherlands, in order to increase knowledge and awareness of this disease.

METHODS

We collected clinical, biochemical and genetic data from four patients from three families diagnosed with HH type 3 in the Netherlands between 2009 and 2016.

RESULTS

Three women and one man diagnosed with HH type 3 presented with arthralgia and elevated ferritin levels and transferrin saturation (TSAT) at ages 25-41 years. The hepcidin/ferritin ratio as measured in three patients was low. Liver iron content in two patients as assessed by MRI or liver biopsy was highly increased (250 and 362.7 μmol iron/g dry weight, respectively, reference < 35 μmol/g). DNA analysis revealed four different TFR2 pathogenic variants: one nonsense, one splicing and two missense variants, of which three are novel. Phlebotomy decreased the serum iron parameters but did not relieve the arthralgia.

CONCLUSION

In patients with a combination of elevated TSAT and ferritin in the absence of anaemia, and after exclusion of HFE-related HH, rare forms of HH should be considered. In these cases, presentation with arthralgia in young adulthood, low hepcidin/ferritin ratio and/or liver iron content > 100 μmol/g form an indication for analysis of the TFR2 gene. Although type 3 HH is extremely rare, awareness of the disease among physicians is important in order to achieve an early diagnosis and prevent complications, such as liver damage.

Subclinical inflammation influences the association between vitamin A- and iron status among schoolchildren in Ghana

BACKGROUND AND OBJECTIVE

In resource-poor settings, micronutrient deficiencies such as vitamin A deficiency may co-exist with iron-deficiency. In this study we assessed the iron and vitamin A status of schoolchildren and the association between vitamin A and iron status.

METHODS

A cross-sectional design using the baseline data of a dietary intervention trial conducted among randomly selected 5-12 years old schoolchildren (n = 224) from 2 rural schools in northern Ghana. Hemoglobin (Hb), serum ferritin (SF) and serum transferrin receptor (sTfR) concentrations were used as measures of iron status. Retinol binding protein (RBP) was used as a measure of vitamin A status. Subclinical inflammation (SCI) was measured using C-reactive protein (CRP) and α1-acid glycoprotein (AGP) concentrations. We examined the cross-sectional association between vitamin A and iron status biomarkers with multiple linear regressions.

RESULTS

The proportions of schoolchildren with anemia (WHO criteria), iron-deficiency (ID, SF <15μg/l and/or sTfR >8.5mg/l) and iron-deficiency anemia (IDA, concurrent anemia and ID) were 63.8%, 68.3% and 46.4% respectively. Low or marginal vitamin A status (0.70 μmol/l ≤ RBP < 1.05μmol/l) was present in 48.2% while 37.5% of the schoolchildren had vitamin A deficiency (VAD, RBP <0.70 μmol/l). The prevalence of SCI as well as concurrent VAD and ID were 48.7% and 25% respectively. RBP was associated with Hb (β = 7.2, P = 0.05) but not SF (β = 20.7, P = 0.33) and sTfR concentration (β = 12.0, P = 0.63). In the presence of SCI, RBP was not associated with hemoglobin status but a significant positive association was observed among children without SCI.

CONCLUSIONS

The study shows that RBP is significantly associated with Hb concentration but not with SF and sTfR. The observed relationship between RBP and Hb is only significant in the absence of SCI.

Effect of testosterone on hepcidin, ferroportin, ferritin and iron binding capacity in patients with hypogonadotropic hypogonadism and type 2 diabetes

CONTEXT

As the syndrome of hypogonadotropic hypogonadism (HH) is associated with anaemia and the administration of testosterone restores haematocrit to normal, we investigated the potential underlying mechanisms.

DESIGN

Randomized, double-blind, placebo-controlled trial.

METHODS

We measured basal serum concentrations of erythropoietin, iron, iron binding capacity, transferrin (saturated and unsaturated), ferritin and hepcidin and the expression of ferroportin and transferrin receptor (TR) in peripheral blood mononuclear cells (MNC) of 94 men with type 2 diabetes. Forty-four men had HH (defined as subnormal free testosterone along with low or normal LH concentrations) while 50 were eugonadal. Men with HH were randomized to testosterone or placebo treatment every 2 weeks for 15 weeks. Blood samples were collected at baseline, 3 and 15 weeks after starting treatment. Twenty men in testosterone group and 14 men in placebo group completed the study.

RESULTS

Haematocrit levels were lower in men with HH (41·1 ± 3·9% vs 43·8 ± 3·4%, P = 0·001). There were no differences in plasma concentrations of hepcidin, ferritin, erythropoietin, transferrin or iron, or in the expression of ferroportin or TR in MNC among HH and eugonadal men. Haematocrit increased to 45·3 ± 4·5%, hepcidin decreased by 28 ± 7% and erythropoietin increased by 21 ± 7% after testosterone therapy (P < 0·05). There was no significant change in ferritin concentrations, but transferrin concentration increased while transferrin saturation and iron concentrations decreased (P < 0·05). Ferroportin and TR mRNA expression in MNC increased by 70 ± 13% and 43 ± 10%, respectively (P < 0·01), after testosterone therapy.

CONCLUSIONS

The increase in haematocrit following testosterone therapy is associated with an increase in erythropoietin, the suppression of hepcidin, and an increase in the expression of ferroportin and TR.

Iron homeostasis after blood transfusion in stable preterm infants - an observational study

AIM

To evaluate the short-term effects of blood transfusion on iron status [hemoglobin, ferritin, soluble transferrin receptor (sTfR), and reticulocyte count], hepcidin, and erythropoietin in stable preterm infants.

METHOD

Sixty-three preterm infants treated with red blood cell transfusions (RBCTs) were included. Venous blood samples were collected before and within 24 h after each transfusion.

RESULTS

Hemoglobin concentration increased after RBCT (7.2±1.2 g/dL vs. 13.7±2.3 g/dL, P=0.02), as well as ferritin [131 (63-110.4) ng/mL vs. 211 (125.7-299.2) ng/mL, P=0.05); reticulocyte count decreased. sTfR did not change. Hepcidin serum levels increased from 37.5 (21.3-84.7) ng/mL to 72.6 (31.3-126.2) ng/mL, (P=0.04) and erythropoietin decreased (48±19 pg/mL vs. 29±17 pg/mL, P=0.06) after RBCT. A positive linear correlation was found (R2=0.76, P=0.0001) between hepcidin and ferritin levels of post-minus-pre RBCT. Hepcidin levels increased significantly in preterm infants who received RBCT after 1 month of age compared to those who received RBCT at <1 month (P=0.03). No correlation was found between gestational age, weight appropriate for age, or length of blood storage and hepcidin levels.

CONCLUSION

Preterm infants can control iron levels by regulating hepcidin and decreasing erythropoietin. This ability varies with postnatal age.

Iron Deficiency in the Acute-Phase Reaction After Open Aortic Surgery

The objective of this study was to quantify the magnitude of iron deficiency in the postoperative period after open aortic surgery. This was a prospective observational study in 55 consecutive patients. Blood samples were obtained on postoperative days 1, 2, 4, 30, and 45, and the parameters determined were the following: iron, transferrin, transferrin saturation index, transferrin-soluble receptor, ferritin, red cell count, hemoglobin, hematocrit, serum C-reactive protein, fibrinogen, mean corpuscular volume, mean corpuscular hemoglobin, mean corpuscular hemoglobin concentration, and number of blood units transfused. We performed statistical ANOVA test for repetitive measurements (lower bound) in regard to its basal level. Iron deficiency and its parameters reached the maximum at 48 hours postoperatively (iron: 18.92 g/dL and transferrin saturation index: 11.1%) (P <.05). There was not a complete recovery after 45 days (iron: 51.23 g/dL and transferrin saturation index: 18.0%) (P <.05). A similar evolution was observed in the other measured parameters (red cell count: 3.5 x 106/L.; hemoglobin: 10.4 g/dL; hematocrit: 30.7%) (P <.005), none affecting the values of concentration or volume (P <.05). Transferrin-soluble receptors, normal at first, were increased at postoperative days 30 and 45 (2.7 and 2.4 mg/dL respectively, P <.005). After open aortic surgery there is an important acute-phase reaction, a dramatic iron deficiency, and a lack of its transporters until the 45th analyzed day. The elevation of transferrin-soluble receptors in the 4th and 6th weeks denotes a necessity of iron supplementation for a correct development of the immature hematic cells since blood parameters do not reach normal levels in the 6th postoperative week.

Supplementation of vitamin B12 or folic acid on hemoglobin concentration in children 6-36 months of age: A randomized placebo controlled trial

BACKGROUND & AIMS

The main objective of this report is to measure to what extent folate or vitamin B12 given daily for 6 months to young North Indian Children improves hemoglobin (Hb) concentration.

METHODS

In a randomized placebo controlled trial in low-to-middle income neighborhoods in New Delhi, India, children were randomized into four groups in a 1:1:1:1 ratio and supplemented daily for 6 months with 2 RDAs of vitamin B12, folic acid, both, or placebo. All children with anemia at baseline were given iron supplementation daily for 2 months. We measured the plasma concentrations of soluble transferrin receptor (sTfR), folate, vitamin B12, total homocysteine (tHcy) and Hb in 262 children.

RESULTS

Mean Hb concentration decreased in all four study groups during the six months of follow up and supplementation of either or both of the vitamins did not improve the Hb concentration. Iron supplements for the initial 2 mo had limited effect on anemia at 6 mo as almost 90% were still anemic at study end.

CONCLUSION

Supplementation of folic acid and/or vitamin B12 for 6 months does not improve Hb concentration in young children. Our findings do not argue for widespread vitamin B12 or folic acid supplementation to combat anemia. Our results also call for alternative strategies to improve iron status and treat iron deficiency anemia.

CLINICAL TRIAL REGISTRY

NCT00717730 at www.clinicaltrials.gov, CTRI No.: CTRI/2010/091/001090 at www.ctri.nic.in.

Hepcidin and iron metabolism associated with cardiometabolic risk factors in children: A case-control study

BACKGROUND AND AIMS

Iron metabolism plays a crucial role in the development of cardiometabolic disease; however, the association between cardiometabolic risk factors (CMRFs) and hepcidin as well as other iron parameters remains unclear in children. The aims of this study were to compare the circulating hepcidin levels and iron metabolism between children with and without CMRFs and to investigate the association between those iron parameters and CMRFs.

METHODS AND RESULTS

A case-control study was conducted among 1126 children aged 7-14 years in the case group (n = 563) with CMRFs and the healthy control group (n = 563). Iron parameters, lipids, and anthropometric characteristics were evaluated. The information on demographics, diet, and physical activities was either children reported or parent reported. Compared with the healthy controls, children with CMRFs had higher levels of hepcidin and lower levels of serum iron, transferrin, and soluble transferrin receptor (sTfR; P < 0.001). Besides, the odds ratios (ORs) for low levels of high-density lipoprotein (HDL) were 2.03, 0.21, and 0.33 in children with higher hepcidin, transferrin, and sTfR levels (P < 0.05). Furthermore, ORs for cardiometabolic risk were 0.50 (95% confidence interval (CI): 0.30-0.85, P < 0.05), 0.22 (95% CI: 0.12, 0.42, P < 0.01) and 0.19 (95% CI: 0.10, 0.36, P < 0.01) in children with higher serum iron, transferrin, and sTfR levels, respectively.

CONCLUSION

The levels of hepcidin were higher, while those of iron, transferrin, and sTfR were lower in children with CMRF. Hepcidin was positively associated with the risk of low HDL levels, whereas transferrin and sTfR levels negatively correlated with the risk of low HDL levels. In addition, serum iron, transferrin, and sTfR levels were negatively associated with cardiometabolic risk.

GDF-15, iron, and inflammation in early chronic kidney disease among elderly patients

PURPOSE

The aim of the study was to assess GDF-15 and iron status in patients in early stages of chronic kidney disease with a particular emphasis on elderly population in association of classic iron status parameters with novel iron homeostasis biomarkers and inflammatory parameters.

METHODS

Serum concentrations of GDF-15, iron (Fe), transferrin saturation, soluble transferrin receptor (sTfR), hepcidin, high-sensitive C-reactive protein (hsCRP), interleukin 6 (IL-6), and hemoglobin were measured in 56 patients ≥65 years of age and in 31 <65 years of age.

RESULTS

In patients ≥65 years, serum concentrations of GDF-15 and hsCRP were significantly higher in comparison with younger group. There was no statistically significant difference in hemoglobin, iron, hepcidin, and sTfR concentration between the two studied groups. In both groups GDF-15 was significantly correlated with hemoglobin, eGFR, hsCRP, and IL-6. GDF-15 was significantly higher in patients with anemia in comparison with their non-anemic counterparts. In multivariate analysis, hemoglobin was found to be a predictor of log GDF-15 (beta value = 0.36, P = 0.006, R (2) = 37 %).

CONCLUSIONS

An intricate interplay between renal function, anemia, and GDF-15 concentrations awaits further studies, as there are few data regarding pathophysiological role of GDF-15 in diabetes, kidney disease, and other comorbidities. Further understanding regarding the signaling pathways of GDF-15 may help to discover next pieces in the exciting puzzle of GDF-15. Finally, as studies dealing with normal level of GDF-15 in the healthy aged are lacking, it is possible that the higher values of GDF-15 values found in the present study represent values of GDF-15 according to age more than CKD levels.

Assessment of serum bioactive hepcidin-25, soluble transferrin receptor and their ratio in predialysis patients: Correlation with the response to intravenous ferric carboxymaltose

BACKGROUND

No reliable biomarker exists to predict responsiveness to intravenous (IV) iron (Fe) in iron deficient patients with CKD. We aimed to investigate the clinical value of bioactive Hepcidin-25 and soluble Transferrin Receptor (sTfR) levels in predialysis patients.

PATIENTS AND METHODS

In this prospective study 78 stable stage III-IV CKD predialysis patients with (responders) (40 patients) and without (non-responders) (38 patients) adequate erythropoiesis after IV administration of ferric-carboxymaltose (FCM). Patients were divided in two groups according to their response to IV administration of ferric-carboxymaltose (FCM). Along with measurements of common hematologic and blood chemistry parameters, determinations of sTfR and bioactive Hepcidin-25 were performed.

RESULTS

Hepcidin-25 levels were lower in the responders (p=0.025), while sTfR and sTfR/Hepcidin-25 ratio were higher (p<0.01 and p=0.002 respectively). Diagnostic efficacy indicated cut off point of 1.49 for Hepcidin-25 had sensitivity 84% and specificity 48%, while cut off point of 1.21 for sTfR/Hepcidin-25 ratio had sensitivity 82% and specificity 52% to predict correctly response to iron supplementation therapy. Furthermore, log sTfR/Hepcidin-25 correlated negatively with hs-CRP (p=0.005) and IL-6 (p<0.04) in non-responders, while such correlations were not found in responders (p>0.05).

CONCLUSIONS

These results suggest that lower Hepcidin-25, as well as higher sTfR and sTfR/Hepcidin-25 ratio were significant predictors of favorable hemoglobin response within a month after IV administration of FCM in patients with CKD. Further experiments and clinical studies in other groups of patients are needed to better elucidate the role of Hepcidin-25 and sTfR/Hepcidin-25 ratio as predictors of response to intravenous iron administration.

The Content of Reticulocyte Hemoglobin and Serum Concentration of the Soluble Transferrin Receptor for Diagnostics of Anemia in Chronically Hemodialyzed Patients

BACKGROUND

Chronic renal disease constitutes a serious worldwide clinical problem. An important issue arising early during the treatment of renal failure is anemia. Patients in the end-stage of renal disease chronically treated with hemodialysis frequently suffer from anemia with iron deficiency.

OBJECTIVES

The aim of the study was to evaluate the usefulness of determining the reticulocyte hemoglobin content and serum concentration of soluble transferrin receptor in the detection of anemia caused by iron deficiency in comparison with the classic markers of iron circulation in serum in chronic dialysis patients with ESRD.

MATERIAL AND METHODS

66 sets of hematologic results and iron turnover rates were analyzed, sampled from hemodialyzed patients (test group), as well as 34 sets of the same results taken from healthy people (control group). Statistically significant variables were found and a stepwise backward discriminant analysis was performed for them.

RESULTS

The results showed that dialyzed patients have a significantly lower serum concentration of hemoglobin, CHr, HCT, TSAT, Fe and TIBC and significantly higher serum concentration of sTfR, ferritin and C-reactive protein compared to the control group. Based on the results of discriminant analysis, we proposed a scheme for assessing the risk of anemia.

CONCLUSIONS

The concentrations of hemoglobin, soluble transferrin receptor, iron in the serum and C-reactive protein turned out to be the most useful for diagnostic purposes. Moreover, the concentration of soluble transferrin receptor confirmed its high diagnostic value in the detection of iron deficiency-based anemia in patients undergoing dialysis for chronic renal failure at the end-stage compared to conventional iron turnover ratios in the serum.

[The main metabolites of ferrokinetics in differentiated diagnostic of anemic syndrome]

The article presents data concerning clinical significance of interleukin 6, hepcidin-25 and its predecessor prohepcidin in differentiated diagnostic of anemic syndrome. The sampling of 192 workers of the oncologic center undergoing annual dispensarization was examined. The genuine reference values for immune enzyme (interleukin 6, hepcidin-25, prohepcidin, soluble receptors of transferrin, ferritin, erythropoietin) techniques are presented. The analysis of results demonstrated that values of interleukin 6, hepcidin-25, prohepcidin can be applied as additional diagnostic criteria of anemic syndrome and especially in differentiated diagnostic of anemia of chronic disease with functional iron deficiency. The carried out study is a new perspective direction of modern concept of iron metabolism in patients with anemic syndrome.

Associations among Erythroferrone and Biomarkers of Erythropoiesis and Iron Metabolism, and Treatment with Long-Term Erythropoiesis-Stimulating Agents in Patients on Hemodialysis

BACKGROUND

We aimed to identify associations between erythroferrone (ERFE), a regulator of hepcidin 25, and biomarkers of erythropoiesis and iron metabolism. We also aimed to determine the effects of erythropoiesis-stimulating agents (ESA), continuous erythropoietin receptor activator (CERA) and darbepoetin-α (DA) on ERFE production in patients on hemodialysis (HD).

METHODS

Blood samples were obtained from 59 patients before HD sessions on day 0 (baseline). Twenty patients who were injected with either CERA (N = 10) or DA (N = 10) at the end of the dialysis week (day 0), who had ferritin ≥ 100 ng/mL and/or transferrin saturation ≥ 20%, and hemoglobin > 9 g/dL were selected from among the 59 patients. Blood was sampled serially before HD sessions on days 3, 5, 7 from patients on DA and on the same days plus day 14 from those on CERA.

RESULTS

Levels of ERFE correlated inversely with those of hepcidin 25 and ferritin, and positively with those of soluble transferrin receptor. The hepcidin 25: ERFE ratio and hepcidin 25 levels positively correlated with ferritin levels. Levels of ERFE significantly increased from day 3 of treatment with DA and CERA and decreased by days 7 and 14, respectively. Erythropoiesis-stimulating agents concomitantly decreased levels of hepcidin 25 as those of ERFE increased.

CONCLUSION

We identified a novel association between ESA and ERFE in patients on HD. Both DA and CERA increased levels of ERFE that regulated hepcidin 25 and led to iron mobilization from body stores during erythropoiesis.

[THE DIFFERENTIAL DIAGNOSTIC POSSIBILITIES IN EVALUATION OF IRON-DEFICIENT CONDITION UNDER ANEMIAS]

The article presents data concerning differential diagnostic possibilities of evaluation of genuine iron-deficient anemia and anemia of chronic diseases. The variety of mechanisms of development of anemia of chronic diseases is demonstrated, including effect of humoral inhibitors of erythropoiesis, disorder of iron metabolism at the expense of its redistribution into cells of macrophage system, suppression of erythropoiesis resulted in redistributed or functional iron deficiency. The data is presented concerning significance in diagnostic of anemia of chronic diseases of such factors as content of ferritin, dissolving receptors of transferrin and role of hepcidin protein in pathogenesis of anemia of chronic diseases. The analysis of scientific publications demonstrated that hepcidin is a negative regulator of iron metabolism. Under iron-deficient anemia its level in blood decreases that contribute to extensive absorption of iron in gastrointestinal tract. On the contrary, under anemia of chronic diseases its content drastically increases and results in blocking of iron transport everywhere, including internal epithelium, macrophages, placenta and other types of cells. The hyper-production of hepcidin during infection and inflammation is responsible for anemia of chronic diseases. The perspectives of development of pharmaceuticals decreasing level of hepcidin for treatment of anemia of chronic diseases is demonstrated.

Serum Hepcidin Levels in Childhood-Onset Ischemic Stroke: A Case-Control Study

Recently, hepcidin, an antimicrobial-like peptide hormone, has evolved as the master regulator of iron homeostasis. Despite the growing evidence of iron imbalance in childhood-onset ischemic stroke, serum hepcidin level in those patients has not yet been researched. In this study, we aimed to estimate serum (hepcidin) level in acute ischemic stroke (AIS) patients and to investigate whether subcutaneous enoxaparin sodium, which is a low-molecular-weight heparin (LMWH) derivative, could modulate serum hepcidin level in those patients. This was a case-control study included 60 (AIS) cases, and 100 healthy children with comparable age and gender as control group. For all subjects' serum hepcidin, interleukin-6 (IL-6), and soluble transferrin receptor [sTfR]) levels were assessed by (enzyme-linked immunosorbent assay [ELISA] method). Iron parameters including (serum iron, ferritin, transferrin, and total iron binding capacity [TIBC]) were also measured. The patients were subdivided according to treatment with an LMWH derivative into 2 groups and serum hepcidin levels were assessed initially and 1 week after stroke onset for all cases. We found that AIS cases had higher serum iron, ferritin, and IL6 levels compared to the control group (all P < 0.01). Serum hepcidin was significantly higher in AIS cases (median, 36[15-73]ng/mL) compared to the control group (median, 24[10-41]ng/mL; P < 0.01). On the 1st day of AIS diagnosis, serum hepcidin levels were similar in both stroke subgroups (P > 0.05). However, on the 7th day of diagnosis serum hepcidin level decreased significantly in AIS cases treated with LMWH (group 1) (median, 36 vs 21 ng/mL; P < 0.01, respectively). Meanwhile, no significant change was observed in serum hepcidin level in AIS cases not treated with LMWH (group 2) (P > 0.05). Serum hepcidin showed significant positive correlations with serum iron, transferrin saturation, ferritin, and IL6 (r = 0.375, P < 0.05; r = 0.453, P < 0.05; r = 0.687, P < 0.01; r = 0.515, P < 0.01; respectively). Our data brought a novel observation of elevated serum hepcidin level in pediatric AIS patients and pointed out that treatment with LMWH could modulate hepcidin level in those patients.

Anemia and Micronutrient Status of Women of Childbearing Age and Children 6-59 Months in the Democratic Republic of the Congo

Little is known about the micronutrient status of women and children in the Democratic Republic of the Congo, which is critical for the design of effective nutrition interventions. We recruited 744 mother-child pairs from South Kivu (SK) and Kongo Central (KC). We determined hemoglobin (Hb), serum zinc, vitamin B12, folate, ferritin, soluble transferrin receptor (sTfR), retinol binding protein (RBP), C-reactive protein, and α-1 acid glycoprotein concentrations. Anemia prevalence was determined using Hb adjusted for altitude alone and Hb adjusted for both altitude and ethnicity. Anemia prevalence was lower after Hb adjustment for altitude and ethnicity, compared to only altitude, among women (6% vs. 17% in SK; 10% vs. 32% in KC), children 6–23 months (26% vs. 59% in SK; 25% vs. 42% in KC), and children 24–59 months (14% vs. 35% in SK; 23% vs. 44% in KC), respectively. Iron deficiency was seemingly higher with sTfR as compared to inflammation-adjusted ferritin among women (18% vs. 4% in SK; 21% vs. 5% in KC), children 6–23 months (51% vs. 14% in SK; 74% vs. 10% in KC), and children 24–59 months (23% vs. 4% in SK; 58% vs. 1% in KC). Regardless of indicator, iron deficiency anemia (IDA) never exceeded 3% in women. In children, IDA reached almost 20% when sTfR was used but was only 10% with ferritin. Folate, B12, and vitamin A (RBP) deficiencies were all very low (<5%); RBP was 10% in children. The prevalence of anemia was unexpectedly low. Inflammation-adjusted zinc deficiency was high among women (52% in SK; 58% in KC), children 6–23 months (23% in SK; 20% in KC), and children 24–59 months (25% in SK; 27% in KC). The rate of biochemical zinc deficiency among Congolese women and children requires attention.

Prevalence of anemia and associations between neonatal iron status, hepcidin, and maternal iron status among neonates born to pregnant adolescents

BACKGROUND

Little is known about anemia and iron status in US newborns because screening for anemia is typically not undertaken until 1 y of age. This study was undertaken to characterize and identify determinants of iron status in newborns born to pregnant adolescents.

METHODS

Pregnant adolescents (≤ 18 y, n = 193) were followed from ≥ 12 wk gestation until delivery. Hemoglobin, ferritin, soluble transferrin receptor, serum iron, hepcidin, erythropoietin (EPO), IL-6, and C-reactive protein were assessed in maternal and cord blood.

RESULTS

At birth, 21% of the neonates were anemic (Hb < 13.0 g/dl) and 25% had low iron stores (ferritin < 76 µg/l). Cord serum ferritin concentrations were not significantly associated with gestational age (GA) at birth across the range of 37-42 wk. Neonates born to mothers with ferritin < 12 µg/l had significantly lower ferritin (P = 0.003) compared to their counterparts. Hepcidin and IL-6 were significantly (P < 0.05) higher in neonates born to mothers with longer durations of active labor.

CONCLUSION

Given the importance of the iron stores at birth on maintenance of iron homeostasis over early infancy, additional screening of iron status at birth is warranted among those born to this high risk obstetric population.

Biomarkers of iron metabolism are independently associated with impaired glucose metabolism and type 2 diabetes: the KORA F4 study

OBJECTIVE

Iron has been suggested to play a role in the etiology of type 2 diabetes mellitus (T2DM). Except for ferritin, evidence is sparse for other markers of iron metabolism that are regulated differently and might act through independent pathways. We therefore investigated the associations of serum ferritin, transferrin, soluble transferrin receptor (sTfR), transferrin saturation (TSAT), sTfR-to-log10ferritin (sTfR-F) index, and iron with impaired glucose metabolism (IGM/'prediabetes'), T2DM, and four continuous glucose and insulin traits.

DESIGN AND METHODS

Data from 2893 participants of the population-based Cooperative Health Research in the Region of Augsburg (KORA) F4 study (Germany) was investigated through regression analysis. The results were adjusted for socio-demographic, life-style, and obesity measures as well as metabolic, inflammatory, and other iron biomarkers following a step-wise approach. Non-linearity was tested by adding a non-linear spline component to the model.

RESULTS

Ferritin and transferrin were positively associated with IGM (fourth vs first sex-specific quartile: ferritin odds ratio (OR)=2.08 (95% CI 1.43-3.04) and transferrin OR=1.89 (95% CI 1.32-2.70)), T2DM (ferritin OR=1.98 (95% CI 1.22-3.22) and transferrin OR=2.42 (95% CI 1.54-3.81)), and fasting as well as 2-h glucose. TSAT (OR=0.55 (95% CI 0.34-0.88)) and iron (OR=0.61 (95% CI 0.38-0.97)) were inversely associated with T2DM, sTfR-F-index was inversely associated with IGM (OR=0.67 (95% CI 0.48-0.95)). There was no strong evidence for non-linear relationships.

CONCLUSIONS

The observed associations of several markers of iron metabolism with hyperglycemia and insulin resistance suggest that iron stores as well as iron-related metabolic pathways contribute to the pathogenesis of IGM and T2DM. Moreover, TSAT levels are decreased in T2DM patients.

[Study on iron store status for women in the poor rural areas in China from 2010 to 2012]

OBJECTIVE

To quantitatively assess the concentration and the distribution of the body iron (BI) for women in the poor rural areas.

METHODS

Resampling based on the blood sample of Nutrition and Health Survey in China from 2010 to 2012, serum ferritin (SF) and serum soluble transferrin receptor (sTfR) were measured for the selected blood samples by immunoturbidimetric assay. BI was calculated, and the concentrations and distribution in different aged subgroup were assessed. Distribution of BI subgrouped in different aged women was compared. The correlations of BI to hemoglobin (Hb), SF and sTfR were analyzed.

RESULTS

The average levels of BI were (7.35 ± 2.37) mg/kg for schoolgirls aged 6-11 years, (6.50 ± 3.59) mg/kg for adolescent girls aged 12-17 years, (6.07 ± 4.78) mg/kg for women of childbearing aged 18-44 years, (8.60 ± 4.45) mg/kg for women aged 45-59 years, and (10.35 ± 3.38) mg/kg for elderly female aged ≥ 60 years, respectively. The proportion of low BI in the 12-17 years and 18-44 years women was the highest. BI level was positively correlated to SF and negatively correlated to sTfR (P < 0.01). BI level was positively correlated to Hb in the BI < 0 mg/kg subgroup.

CONCLUSION

The BI methodology allows the full range of iron status of populations to be evaluated. The iron status for adolesecent girls aged 12-17 years and women of childbearing aged 18-44 years should be improved.

Beyond soluble transferrin receptor: old challenges and new horizons

Disturbances of iron metabolism are a frequent challenge in outpatient and inpatient care. Although several established biomarkers are commonly used by clinicians for differential diagnosis, the discrimination between latent or classic iron deficiency, anaemia of chronic disease or a combination of functional iron deficiency (iron-restricted erythropoiesis) with anaemia of chronic disease in patients affected by inflammatory disease can be demanding. Soluble transferrin receptor (sTfR) is a cleaved monomer of transferrin receptor 1 and correlates positively with tissue iron deficiency as well as with stimulated erythropoiesis. The ratio between sTfR and ferritin in combination with reticulocyte haemoglobin content further helps to identify different states of iron deficiency. In this review, we will focus on biological aspects of iron metabolism and sTfR, established clinical applications and limitations of sTfR and derived indices, and prospects of future research and applications.

Immunophenotypic Profiling of Erythroid Progenitor-Derived Extracellular Vesicles in Diamond-Blackfan Anaemia: A New Diagnostic Strategy

Diamond-Blackfan Anaemia (DBA) is a rare inherited anaemia caused by heterozygous mutations in one of 13 ribosomal protein genes. Erythroid progenitors (BFU-E and CFU-E) in bone marrow (BM) show a proapoptotic phenotype. Suspicion of DBA is reached after exclusion of other forms of BM failure syndromes. To improve DBA diagnosis, which is confirmed by mutation analysis, we tested a new approach based on the study of extracellular vesicles (EVs) isolated from plasma by differential centrifugations and analysed by flow cytometry. We chose CD34, CD71 and CD235a markers to study erythroid EVs. We characterised the EVs immunophentoypic profiles of 13 DBA patients, 22 healthy controls and 16 patients with other haematological diseases. Among the three EVs clusters we found, only the CD34+/CD71_low population showed statistically significant differences between DBA patients and controls (p< 0.05). The absence of this cluster is in agreement with the low levels of BFU-E found in DBA patients. The assessment of ROC curves demonstrated the potential diagnostic value of this population. We suggest that this assay may be useful to improve DBA diagnosis as a quicker and less invasive alternative to BM BFU-E culture analysis.