Laboratory variables for assessing iron deficiency in REDS-II Iron Status Evaluation (RISE) blood donors

'Ironing out the risk': Assessing the effect of plateletpheresis donation frequency on iron stores in South-Asian male donors

BACKGROUND AND OBJECTIVES

Repeated blood donation is a well-known cause of iron deficiency among donors. However, present scientific literature lacks comprehensive evidence regarding the impact of regular plateletpheresis procedures on body iron reserves. In this study, we aimed to detect and correlate iron deficiency (using iron indices) with the frequency of platelet donations. Additionally, we also analysed the correlation between other iron and haematological indices with serum ferritin to determine cost-effective parameters that may serve as an initial screening approach to determine which donors should be subjected to serum ferritin testing.

MATERIALS AND METHODS

A total of 180 male participants from our platelet donor registry were enrolled in this observational cross-sectional study. Enrolment questionnaires were administered to eligible donors, and biological samples were collected during plateletpheresis donation. Biological tests such as complete blood count, reticulocyte indices, iron indices, vitamin B12 and folate were performed.

RESULTS

Donors with ≥12 donations per year showed the highest prevalence of low ferritin (serum ferritin: 15-30 ng/mL) and absent iron stores (serum ferritin <15 ng/mL) (41.3% and 26.7%, respectively). Ferritin showed a significant negative correlation with recent (r = -0.346) and lifetime donations (r = -0.196). The efficacy of other indices for identifying iron depletion was much better using a serum ferritin value <15 ng/mL.

CONCLUSION

Regular plateletpheresis donations can lead to varying severities of non-anaemic iron deficiency. Blood centres must regularly monitor frequent plateletpheresis donors (especially donors with more than 11 donations in a calendar year) and ideally maintain their serum ferritin above 30 ng/mL.

Assessment of iron status in regular blood donors in a tertiary care hospital in Southern India

BACKGROUND

Regular blood donation depletes iron stores. The assertion is that the vulnerable donor population requires a predictive standard operative procedure for early detection of iron store depletion, preventing them from developing iron-deficiency anemia.

AIM

This study aims to study the potential effects of blood donation in the regular donor group using hematological and biochemical estimation of iron status parameters.

STUDY SETTINGS AND DESIGN

This was a prospective cross-sectional study on regular blood donors, defined as those who have donated at least 3 times, the last donation being within the last 12 months and continues to donate at least once a year, at a tertiary care teaching hospital in Southern India.

MATERIALS AND METHODS

The complete blood count (CBC) was performed on the Sysmex coulter, and the red cell indices were calculated. The ferritin and the soluble transferrin receptor (sTfR) assays were performed using Enzyme Immunoassays.

STATISTICAL ANALYSIS USED

The comparison of CBC, serum ferritin, and sTfR assay with donation frequency and time since the last donation was carried out using an independent student's t-test for two groups. The statistical analysis was performed using SPSS for Windows version 20.

RESULTS

A total of 323 regular blood donors (6 were females) were included in the study of which they were categorized into three, 211 donors with less than or equal to 10 donations, 84 those who had donated between 11 and 20 times and 28 who had donated more than 20 times. The red cell indices were reduced and different in the groups but not statistically significant except for mean corpuscular volume. About 15% of the study population had a transferrin level of <15 ng/ml. The Ferritin levels showed a statistically significant negative correlation with the number of donations, the correlation coefficient being -0.27. Logarithmic ratios of sTfR/ferritin also correlated with a coefficient of 0.156 with the number of donations and were statistically significant.

CONCLUSION

Our study found that regular blood donors had low iron stores, as shown by ferritin levels and other iron indicators. Using the current guidelines (hemoglobin >12.5 g/dL) for donation, or the red cell indices alone do not reflect the donor's actual iron status.

Potential of cell tracking velocimetry as an economical and portable hematology analyzer

Anemia and iron deficiency continue to be the most prevalent nutritional disorders in the world, affecting billions of people in both developed and developing countries. The initial diagnosis of anemia is typically based on several markers, including red blood cell (RBC) count, hematocrit and total hemoglobin. Using modern hematology analyzers, erythrocyte parameters such as mean corpuscular volume (MCV), mean corpuscular hemoglobin (MCH), etc. are also being used. However, most of these commercially available analyzers pose several disadvantages: they are expensive instruments that require significant bench space and are heavy enough to limit their use to a specific lab and lead to a delay in results, making them less practical as a point-of-care instrument that can be used for swift clinical evaluation. Thus, there is a need for a portable and economical hematology analyzer that can be used at the point of need. In this work, we evaluated the performance of a system referred to as the cell tracking velocimetry (CTV) to measure several hematological parameters from fresh human blood obtained from healthy donors and from sickle cell disease subjects. Our system, based on the paramagnetic behavior that deoxyhemoglobin or methemoglobin containing RBCs experience when suspended in water after applying a magnetic field, uses a combination of magnets and microfluidics and has the ability to track the movement of thousands of red cells in a short period of time. This allows us to measure not only traditional RBC indices but also novel parameters that are only available for analyzers that assess erythrocytes on a cell by cell basis. As such, we report, for the first time, the use of our CTV as a hematology analyzer that is able to measure MCV, MCH, mean corpuscular hemoglobin concentration (MCHC), red cell distribution width (RDW), the percentage of hypochromic cells (which is an indicator of insufficient marrow iron supply that reflects recent iron reduction), and the correlation coefficients between these metrics. Our initial results indicate that most of the parameters measured with CTV are within the normal range for healthy adults. Only the parameters related to the red cell volume (primarily MCV and RDW) were outside the normal range. We observed significant discrepancies between the MCV measured by our technology (and also by an automated cell counter) and the manual method that calculates MCV through the hematocrit obtained by packed cell volume, which are attributed to the artifacts of plasma trapping and cell shrinkage. While there may be limitations for measuring MCV, this device offers a novel point of care instrument to provide rapid RBC parameters such as iron stores that are otherwise not rapidly available to the clinician. Thus, our CTV is a promising technology with the potential to be employed as an accurate, economical, portable and fast hematology analyzer after applying instrument-specific reference ranges or correction factors.

Utility of Novel Hypochromia and Microcythemia Markers in Classifying Hematological and Iron Status in Male Athletes

In athletes, no reliable indices exist for an unambiguous evaluation of hematological and iron status. Therefore, the utility of some new red blood cell (RBC) parameters was explored in 931 elite male athletes aged 13–35 years. To diagnose iron status, the values of ferritin and soluble transferrin receptor (sTfR), total iron binding capacity (TIBC), and basic blood morphology were determined in blood. The new hematological markers included among others: mean cellular hemoglobin content in reticulocytes (CHr), percentage of erythrocytes (HYPOm) and reticulocytes (HYPOr) with decreased cellular hemoglobin concentration, percentage of erythrocytes (LowCHm) and reticulocytes (LowCHr) with decreased cellular hemoglobin content, mean volume of reticulocytes (MCVr), and percentage of erythrocytes with decreased volume (MICROm). Despite adverse changes in reticulocyte hypochromia indices (CHr, LowCHr, HYPOr; p < 0.001) in the iron depletion state, the area under the receiver operating characteristic curve (AUC-ROC) values calculated for them were relatively low (0.539–0.722). In iron-deficient erythropoiesis (IDE), unfavorable changes additionally concern microcythemia indices in both reticulocytes and erythrocytes (MCVr, MCV, MICROm, and red cell volume distribution width—RDW), with especially high values of AUC-ROC (0.947–0.970) for LowCHm, LowCHr, and CHr. Dilutional sports anemia was observed in 6.1% of athletes. In this subgroup, only hemoglobin concentration (Hb), hematocrit (Hct), and RBC (all dependent on blood volume) were significantly lower than in the normal group. In conclusion, the diagnostic utility of the new hematology indices was not satisfactory for the detection of an iron depletion state in athletes. However, these new indices present high accuracy in the detection of IDE and sports anemia conditions.

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.

The iron status of South African blood donors: balancing donor safety and blood demand

BACKGROUND

Several studies in developed countries have demonstrated high levels of iron deficiency (ID) among blood donors. There is a paucity of data for developing countries where blood shortages remain a major concern.

STUDY DESIGN AND METHODS

A total of 4412 donors were enrolled in the study. Specimens were collected for full blood count, iron, transferrin saturation, and ferritin assessment. Donor demographics were recorded. ID was indicated by a ferritin level of less than 20 ng/mL for men and less than 12 ng/mL for women. Anemia was defined as hemoglobin levels less than 12.5 g/dL. Regression models for predictors of ID were developed.

RESULTS

A total of 17.5% of all donors had ID, with 16.3% prevalence in women and 18.6% in men. Low hemoglobin had the highest association with ID (adjusted odds ratio [AOR], 11.078; 95% confidence interval [CI], 7.915-15.505); male donors had twice the odds of ID compared to female donors (AOR, 2.501; 95% CI, 1.964-3.185), while increasing age was associated with lower odds (AOD, 0.965; 95% CI, 0.956-0.975). Among male donors, an interdonation interval of less than 3 months (AOR, 2.679; 95% CI, 1.929-3.720) was associated with ID. Compared to other females combined, colored female donors (AOR, 2.335; 95% CI, 1.310-4.160) had higher odds and black female donors (AOR, 0.559; 95% CI, 0.369-0.845) lower odds of ID.

CONCLUSION

ID is common among South African donors; low hemoglobin, gender, ethnicity, and past donation history is independently associated with ID. Recommendations aimed at protecting donor health may increase blood shortages in South Africa.

Altered Red Cell Indices in Repeat Blood Donors: Experience of a North Indian Blood Bank

Subclinical Iron deficiency appearing in blood donors after blood donation is a recognized problem. Donors at an increased risk of iron deficiency need to be identified. Blood donors meeting national selection criteria were included in the study. Complete blood counts were done using Sysmex XP-100 three part hematology analyzer. Differences in RBC indices among donor groups defined by previous donations were then analyzed statistically. Six hundred and seventy three males and ninety six females were studied. In males, Kruskal-Wallis test showed significant differences between groups defined by number of donations for MCH and MCV (P value < 0.001), but not for MCHC (P value = 0.09) and RDW (P value = 0.6). Post-hoc tests showed statistically significant difference between donors having six or more donations compared to donors having no previous donations for both MCH as well as MCV. No significant difference was found between donor subgroups in females for any of the indices; however, no female donated blood more than three times in the study. There is increased risk for iron deficiency in donors having six or more previous donations, and evidence for starting an iron screening and supplementation programme for these donors.

Dysregulated iron metabolism in polycythemia vera: etiology and consequences

Polycythemia vera (PV) is a chronic myeloproliferative neoplasm. Virtually all PV patients are iron deficient at presentation and/or during the course of their disease. The co-existence of iron deficiency and polycythemia presents a physiological disconnect. Hepcidin, the master regulator of iron metabolism, is regulated by circulating iron levels, erythroblast secretion of erythroferrone, and inflammation. Both decreased circulating iron and increased erythroferrone levels, which occur as a consequence of erythroid hyperplasia in PV, are anticipated to suppress hepcidin and enable recovery from iron deficiency. Inflammation which accompanies PV is likely to counteract hepcidin suppression, but the relatively low serum ferritin levels observed suggest that inflammation is not a major contributor to the dysregulated iron metabolism. Furthermore, potential defects in iron absorption, aberrant hypoxia sensing and signaling, and frequency of bleeding to account for iron deficiency in PV patients have not been fully elucidated. Insufficiently suppressed hepcidin given the degree of iron deficiency in PV patients strongly suggests that disordered iron metabolism is an important component of the pathobiology of PV. Normalization of hematocrit levels using therapeutic phlebotomy is the most common approach for reducing the incidence of thrombotic complications, a therapy which exacerbates iron deficiency, contributing to a variety of non-hematological symptoms. The use of cytoreductive therapy in high-risk PV patients frequently works more effectively to reverse PV-associated symptoms in iron-deficient relative to iron-replete patients. Lastly, differences in iron-related parameters between PV patients and mice with JAK2 V617F and JAK2 exon 12 mutations suggest that specific regions in JAK2 may influence iron metabolism by nuanced changes of erythropoietin receptor signaling. In this review, we comprehensively discuss the clinical consequences of iron deficiency in PV, provide a framework for understanding the potential dysregulation of iron metabolism, and present a rationale for additional therapeutic options for iron-deficient PV patients.

Reticulocyte hemoglobin content (MCHr) in the detection of iron deficiency

BACKGROUND

Blood hemoglobin (Hb) concentration within the reference interval does not exclude iron deficiency (ID): individuals with normal stores lose iron during a long period before their Hb falls below of the level that is defined as anemia. The process entails a decrease of storage iron, shown by serum ferritin below reference range, followed by iron depletion, eventually leading to iron restricted erythropoiesis; consequence of an imbalance between erythropoietic iron requirements and too low supply is a reduction of Hb synthesis in reticulocytes.

OBJECTIVE

We study the potential utility of mean reticulocyte hemoglobin content (MCHr), reported by CELL-DYN Sapphire (Abbott Diagnostics) analyzer, in the detection of ID in non-anemic adults.

METHODS

207 patients with Hb within the reference range were enrolled. ID was defined as Hb>120g/L (women), >130g/L (men) and serum ferritin <30μg/L. Student's t-test was applied to detect deviations between groups, statistical significance P<0.05. The performance of MCHr in detecting ID was evaluated applying Receiver Operating Characteristic (ROC) curve analysis. Kappa test was applied to verify concordance between ferritin and MCHr.

RESULTS

68 patients (33%) suffered ID, median MCHr in this group was 26.9 pg, statistically different from the normal group, MCHr 30.9pg (P<0.0001). ROC ANALYSIS (GOLD STANDARD FERRITIN <30μG/L): Area under curve AUC 0.851 (95% CI 0.770-0.912) at cut off 30.0 pg, with sensitivity 84.1% and specificity 71.1%. Kappa 0.667 (95% CI 0.527-0.858).

CONCLUSION

Due to their short lifespan reticulocytes and derived parameters reflect current erythropoiesis status, before Hb and erythrocyte indices drop. MCHr had the best AUC and diagnostic value compared to erythrocyte indices. MCHr is a reliable test for the investigation of ID and could improve the detection of iron deficient adults.

Serum ferritin in plateletpheresis and whole blood donors

BACKGROUND AND OBJECTIVES

We performed a prospective analysis of iron status in plateletpheresis donors, using whole blood donors as a control group, to assess the haematinic effects of regular anti-coagulated extracorporeal circulation and platelet collection.

MATERIALS AND METHODS

Ferritin levels were measured in samples from 31 regular male plateletpheresis donors and from 14 first time male whole blood donors, immediately before and immediately after donation, and immediately before the next donation. An additional 33 regular male plateletpheresis donors and 17 first time male whole blood donors had serum ferritin levels checked predonation.

RESULTS

Male plateletpheresis donors had a statistically significant fall in serum ferritin after donation (P = 0.005)*. In addition, male platelet donors had significantly lower serum ferritin levels than first time male blood donors: ferritin <20 µg/L was found in 6/64 (9%) of regular platelet donors and 1/31 (3%) of first time blood donors (P < 0.001)*.

DISCUSSION

Our studies support the value of serum ferritin measurement in apheresis donor management.

Evaluation of Iron Deficiency Using Reticulocyte Indices in Dogs Enrolled in a Blood Donor Program

Background

People donating blood more than twice annually are at risk of developing iron deficiency. Little is known about the iron status of dogs enrolled in blood donor programs.

Hypothesis

Dogs donating blood ≥6 times annually will show evidence of iron deficiency based on their reticulocyte indices.

Animals

Thirteen dogs enrolled in a blood donor program donating ≥6 times over the preceding 12 months and 20 healthy nondonor control dogs.

Methods

Prospective observational study. Mature red blood cell (RBC) indices, reticulocyte indices, serum iron, serum ferritin, and total iron‐binding capacity (TIBC) were compared between groups.

Results

Packed cell volume (median 47%, range 40–52%, P < .01), hematocrit (median 46.4%, range 40.3–52.5%, P < .01), and reticulocyte count (median 16,000/μL, range 9,000–38,000/μL, P < .01) were significantly lower in the blood donor dogs. No statistically significant differences were noted in the mature RBC indices between groups. Both reticulocyte mean corpuscular volume (median 88.8 fL, range 83.4–95.5 fL, P = .03) and reticulocyte hemoglobin content (median 24.6 pg, range 23.1–26.6 pg, P < .01) were significantly lower in the blood donor group. Serum iron and ferritin were similar between groups; however, TIBC was significantly higher in the control group (median 403 μg/dL, range 225–493 μg/dL, P = .02).

Conclusions

The findings in dogs donating ≥6 times annually suggest the presence of iron‐deficient erythropoiesis in this population.

Evidence of relative iron deficiency in platelet- and plasma-pheresis donors correlates with donation frequency

BACKGROUND

The loss of iron stores and resulting iron deficiency is well documented in whole blood or red blood cell donors. We hypothesized that relative iron deficiency also occurs as a result of more frequent platelet- and plasma-pheresis (apheresis) donation.

MATERIALS AND METHODS

To test this hypothesis, we proposed a pilot cross-sectional study to analyze erythropoiesis- and iron-related parameters in white male apheresis donors: (1) relative to controls, (2) in correlation with apheresis donation frequency, and (3) in correlation with pre-donation platelet count.

RESULTS

Fifty eligible apheresis donors and eight controls were enrolled in the study. Apheresis donors were found to have a lower serum ferritin and serum hepcidin and exhibited evidence of iron restricted erythropoiesis relative to controls. Furthermore, among donors, lower MCV, CH^r , hepcidin concentration, and serum ferritin were observed in more frequent apheresis donors. Correlations between donation frequency and hepcidin and ferritin were noted in apheresis donors.

CONCLUSIONS

This pilot study demonstrates that apheresis donors are relatively iron deficient compared to controls and supports the premise that frequent apheresis donation correlates with relatively iron restricted erythropoiesis. An analysis of iron- and erythropoiesis-related parameters in a broader population of frequent apheresis donors (i.e., female and non-white donors) may demonstrate larger deficits and an even greater potential benefit of iron replacement. J. Clin. Apheresis 31:551-558, 2016. © 2015 Wiley Periodicals, Inc.

Clinical Value of Hypochromia Markers in the Detection of Latent Iron Deficiency in Nonanemic Premenopausal Women

BACKGROUND

Iron deficiency (ID) is the most common cause of anemia in fertile women and hemoglobin (Hb) within the reference interval does not exclude ID. The consequence of an imbalance between the iron requirements and supply is a reduction of red-cell Hb content, which causes hypochromic cells. The aim of this study was to assess the reliability of new parameters low Hb density (LHD%), reticulocyte Hb equivalent (RetHe), and percentage of hypochromic erythrocytes (%HypoHe) in the detection of latent ID (LID), defined as depletion of iron stores without anemia.

METHODS

Two hundred fifty consecutive nonanemic women in fertile age (18-40 years, mean 33.5 years), whose analyses had been requested by general practitioners, were included. Independent samples t-test, receiver operating characteristic (ROC) curve analysis (gold standard for detecting LID ferritin <30 μg/l), and Cohen's kappa index were applied.

RESULTS

One hundred fifty-three women had ferritin within the reference range and Hb >120 g/L; 97 (38.8%) had LID. The results were as follows: %HypoHe-AUC 0.934, cutoff 1.6%, sensitivity 85.7%, specificity 92.1%; RetHe-AUC 0.914, cutoff 29.9 pg, sensitivity 86.8%, specificity 85.7%; LHD%-AUC 0.898, cutoff 5.0%, sensitivity 85.9%, specificity 84.1%. Applying those cutoffs, agreement between ferritin and %HypoHe was κ 0.61 and 0.56 for RetHe and LHD%.

CONCLUSIONS

LHD%, %HypoHe, and RetHe emerge as reliable tests for the investigation of LID and could improve the ability to detect ID before anemia is present.

Risk factors for deferral due to low hematocrit and iron depletion among prospective blood donors in a Brazilian center

Objective

Deferral of blood donors due to low hematocrit and iron depletion is commonly reported in blood banks worldwide. This study evaluated the risk factors for low hematocrit and iron depletion among prospective blood donors in a large Brazilian blood center.

Method

A case–control study of 400 deferred donors due to low hematocrit and 456 eligible whole blood donors was conducted between 2009 and 2011. Participants were interviewed about selected risk factors for anemia, and additional laboratory tests, including serum ferritin, were performed. Bivariate and multivariate analyses were performed to assess the association between predictors and deferral due to low hematocrit in the studied population and iron depletion in women.

Results

Donors taking aspirins or iron supplementation, those who reported stomachache, black tarry stools or hematochezia, and women having more than one menstrual period/month were more likely to be deferred. Risk factors for iron depletion were repeat donation and being deferred at the hematocrit screening. Smoking and lack of menstruation were protective against iron depletion.

Conclusion

This study found some unusual risk factors related to gastrointestinal losses that were associated with deferral of donors due to low hematocrit. Knowledge of the risk factors can help blood banks design algorithms to improve donor notification and referral.

Double red blood cell donors with increased ferritin levels: a descriptive study

BACKGROUND

One of the measures proposed to mitigate iron loss in blood donors is monitoring of their ferritin levels. Occasionally, high ferritin levels are found in monitored donors. We report the results of the clinical and laboratory investigation of 80 double red blood cell (DRBC) donors with high ferritin levels.

STUDY DESIGN AND METHODS

All DRBC donors' ferritin levels were measured during each visit for a donation. Donors with high ferritin levels who agreed to participate underwent a clinical and laboratory evaluation.

RESULTS

A total of 165 of 2757 DRBC donors had at least one high ferritin level. Five were already known to suffer from hemochromatosis. A full investigation was available for 80 other donors. A total of 61 of 80 donors had normalized their ferritin level at the time of their laboratory evaluation. Only 16 donors had high serum iron levels, of whom four had increased saturation index. Genetic analysis gave the following results: C282Y homozygous, two; H63D homozygous, six; C282Y/HC3D double heterozygote, six; C282Y heterozygote, six; H63D heterozygote, 19; and no mutations, 39. None of the other laboratory investigations contributed data explaining the high ferritin levels observed.

CONCLUSION

In most donors with high ferritin levels, the phenomenon was transient, with normal ferritin levels found in follow-up. Less than 10% of these donors had evidence of iron overload. Only eight were homozygous for mutations associated with hemochromatosis. An extensive laboratory investigation by the treating physician should only be recommended in donors with persistently high ferritin levels.

Ask about ice, then consider iron

BACKGROUND AND PURPOSE

The study aims to review a condition defined by the desire to consume ice in order to satisfy an addictive-like compulsion, rather than for purposes of hydration or pain relief. This condition is called ice pica, or pagophagia. Associations between ice pica and iron deficiency, suggestions for clinical screening of at risk populations, and recommendations for treatment and follow-up care are provided.

DATA SOURCES

An extensive literature review of original research articles, reviews, clinical practice manuscripts, and scientific publications on pica and pagophagia.

CONCLUSIONS

A compulsion or craving for the consumption of ice is often overlooked in clinical practice. It is therefore important for clinicians to include ice pica as part of the review of systems for certain patient populations. Ice pica is frequently associated with iron deficiency, and iron supplementation is an effective therapy in most cases.

IMPLICATIONS FOR PRACTICE

Knowledge gained from screening for ice pica can generate valuable patient information and lead to the diagnosis and treatment of iron deficiency. The populations at risk include young women and blood donors of either sex.

Laboratory and genetic assessment of iron deficiency in blood donors

More than 9 million individuals donate blood annually in the United States. Between 200 and 250 mg of iron is removed with each whole blood donation, reflecting losses from the hemoglobin in red blood cells. Replenishment of iron stores takes many months, leading to a high rate of iron depletion. In an effort to better identify and prevent iron deficiency, blood collection centers are now considering various strategies to manage donor iron loss. This article highlights laboratory and genetic tests to assess the iron status of blood donors and their applicability as screening tests for blood donation.

Oral iron supplementation after blood donation: a randomized clinical trial

IMPORTANCE

Although blood donation is allowed every 8 weeks in the United States, recovery of hemoglobin to the currently accepted standard (12.5 g/dL) is frequently delayed, and some donors become anemic.

OBJECTIVE

To determine the effect of oral iron supplementation on hemoglobin recovery time (days to recovery of 80% of hemoglobin removed) and recovery of iron stores in iron-depleted ("low ferritin," ≤26 ng/mL) and iron-replete ("higher ferritin," >26 ng/mL) blood donors.

DESIGN, SETTING, AND PARTICIPANTS

Randomized, nonblinded clinical trial of blood donors stratified by ferritin level, sex, and age conducted in 4 regional blood centers in the United States in 2012. Included were 215 eligible participants aged 18 to 79 years who had not donated whole blood or red blood cells within 4 months.

INTERVENTIONS

One tablet of ferrous gluconate (37.5 mg of elemental iron) daily or no iron for 24 weeks (168 days) after donating a unit of whole blood (500 mL).

MAIN OUTCOMES AND MEASURES

Time to recovery of 80% of the postdonation decrease in hemoglobin and recovery of ferritin level to baseline as a measure of iron stores.

RESULTS

The mean baseline hemoglobin levels were comparable in the iron and no-iron groups and declined from a mean (SD) of 13.4 (1.1) g/dL to 12.0 (1.2) g/dL after donation in the low-ferritin group and from 14.2 (1.1) g/dL to 12.9 (1.2) g/dL in the higher-ferritin group. Compared with participants who did not receive iron supplementation, those who received iron supplementation had shortened time to 80% hemoglobin recovery in both the low-ferritin (mean, 32 days, interquartile range [IQR], 30-34, vs 158 days, IQR, 126->168) and higher-ferritin groups (31 days, IQR, 29-33, vs 78 days, IQR, 66-95). Median time to recovery to baseline ferritin levels in the low-ferritin group taking iron was 21 days (IQR, 12-84). For participants not taking iron, recovery to baseline was longer than 168 days (IQR, 128->168). Median time to recovery to baseline in the higher-ferritin group taking iron was 107 days (IQR, 75-141), and for participants not taking iron, recovery to baseline was longer than 168 days (IQR, >168->168). Recovery of iron stores in all participants who received supplements took a median of 76 days (IQR, 20-126); for participants not taking iron, median recovery time was longer than 168 days (IQR, 147->168 days; P < .001). Without iron supplements, 67% of participants did not recover iron stores by 168 days.

CONCLUSIONS AND RELEVANCE

Among blood donors with normal hemoglobin levels, low-dose iron supplementation, compared with no supplementation, reduced time to 80% recovery of the postdonation decrease in hemoglobin concentration in donors with low ferritin (≤26 ng/mL) or higher ferritin (>26 ng/mL).

TRIAL REGISTRATION

clinicaltrials.gov Identifier: NCT01555060.

The value of Ret-Hb and sTfR in the diagnosis of iron depletion in healthy, young children

OBJECTIVES

Reticulocyte hemoglobin (Ret-Hb) content and soluble transferrin receptor (sTfR) are described as promising biomarkers in the analysis of iron status. However, the value of Ret-Hb and sTfR in the early detection of iron depletion, as frequently observed in children in high-income countries, is unclear. We hypothesized that young children to iron depletion, using the WHO cutoff of ferritin <12 μg/l, would have lower Ret-Hb and higher sTfR concentrations compared to children with a ferritin ⩾level 12 μg/l.

SUBJECTS/METHODS

In this cross-sectional study, we analyzed mean concentrations of Ret-Hb and sTfR in 351 healthy children aged 0.5-3 years in a high-income country. The Student's t-test was used to compare Ret-Hb and sTfR concentrations between groups.

RESULTS

We showed that concentrations of Ret-Hb and sTfR are similar in children with and without iron depletion. A decrease in Ret-Hb concentration was present only when ferritin concentrations were <8 μg/l. sTfR concentrations were similar in children with ferritin concentrations <6 μg/l and ⩾12 μg/l.

CONCLUSIONS

Our results showed that the discriminative value of Ret-Hb and sTfR for the detection of iron depletion is limited. Our findings suggest that ferritin is the most useful biomarker in the screening of iron depletion in healthy children in high-income countries. However, ideally, reference ranges of iron status biomarkers should be based on studies showing that children with concentrations outside reference ranges have poor neurodevelopmental outcomes.

Iron deficiency in blood donors: a national cross-sectional study

BACKGROUND

Iron deficiency (ID) is an important consequence of blood donation. The epidemiology of this problem in the blood donor population was therefore studied to enable appropriate targeting of potential solutions to donor ID.

STUDY DESIGN AND METHODS

A nationally representative, cluster-based cross-sectional study of Australian blood donors was performed. Donors were eligible for inclusion if they fulfilled criteria for blood donation or were deferred due to low or falling hemoglobin. Ferritin was measured and demographic and donation data were collected.

RESULTS

A total of 3094 blood donors were recruited, of which samples were collected from 3049 donors; 1873 had exclusively donated whole blood (WB only), 242 had exclusively made apheresis donations, and 530 had not donated ("new" donors) in the previous 24 months. The prevalence of ID in new female donors was 12.0% compared with 1.3% in males. The prevalence of ID in female WB-only donors was 26.4%; it increased with donation frequency and decreased with age. The prevalence in male WB-only donors was 6.3% with no evident change with age or donation frequency. The prevalence of ID in apheresis-only donors (females 6.3%; males 2.2%) did not significantly exceed that of new donors nor did it change with donation frequency. Importantly, the risk of ID could not be satisfactorily predicted in an individual donor by his or her anemia status or with predictive modeling incorporating demographic and donation data.

CONCLUSION

ID is especially prevalent in female, premenopausal, frequent WB donors. Strategies to combat ID should be implemented, specifically targeting this group.

Blood donor iron status: are we bleeding them dry?

PURPOSE OF REVIEW

This review examines the recent research on the prevalence, determinants and importance of low iron in blood donors, and on the efforts to reduce or prevent iron depletion in donor populations.

RECENT FINDINGS

Female donors, especially younger women, are at highest risk for donation-induced low iron, but menopausal women and high-frequency donors of both sexes also face considerable risk for iron depletion. Predonation screening for hemoglobin contributes little information on donor iron status. Consumption of supplemental iron is helpful in preventing or reversing low iron, and waiting longer between donations also facilitates the recovery of the iron lost through donation.

SUMMARY

Although the impact of phlebotomy-related iron depletion on donor health requires better documentation, measures are available now that can be deployed on a targeted or standardized basis. Blood centers, regulators, and donors should continue to evaluate different approaches for addressing this problem, with the likely outcome that no single measure is optimal for maintaining adequate collections while safeguarding donor health.

Low hemoglobin deferral in blood donors

Low hemoglobin deferral occurs in about 10% of attempted whole blood donations and commonly is a consequence of iron deficiency anemia. Pre-menopausal women often have iron deficiency anemia caused by menstruation and pregnancy and have low hemoglobin deferral on their first donation attempt. Frequent donors also develop iron deficiency and iron deficiency anemia because blood donation removes a large amount of iron from the donor and the 56-day minimum inter-donation interval for donors in the United States is not sufficient for recovery of hemoglobin and iron stores. Other causes for low hemoglobin deferral range from a medically insignificant deferral of a woman with hemoglobin between 12.0 and 12.4 g/dL, which is within the normal reference range but below the 12.5 g/dL needed to donate blood, to anemia caused by an unrecognized malignancy in a "healthy" individual attempting to donate blood. The diverse causes of anemia in blood donors make it difficult to provide accurate information to donors about the cause of their low hemoglobin deferral and complicate implementation of programs to prevent them by blood collecting agencies. This article reviews how hemoglobin is measured and the demographics and causes of low hemoglobin deferral in blood donors. It provides recommendations for how blood collection agencies can provide donors with accurate information about the cause of their deferral and discusses programs that can be implemented to decrease these deferrals in regular donors.