Improvement of sickle cell anemia by iron-limited erythropoiesis

We report the hematologic and clinical features of four adult patients (Pts.) with sickle cell anemia and iron-limited erythropoiesis. Two of the Pts. had spontaneous iron deficiency (chronic Gl bleeding, low-grade hemoglobinuria). In the other two Pts. iron restriction was induced by periodic RBC aphereses as part of a pilot protocol designed to decrease intracellular HbS polymerization by MCHC reduction. Iron-limited erythropoiesis was defined by reduction in red cell indices (MCV range 60.4–67 fl) in the presence of low serum ferritin (range <10–20 ng/ml). In these Pts. iron restriction did not cause clinically significant worsening of the anemia (Hb 7.8–9.0 g/dl). In two Pts. the anemia actually improved. Other hematologic effects of iron restriction were: decreased MCHC, reticulocyte count, RDW, and dense cells. A reduced hemolytic rate was suggested by a lowering of serum bilirubin and LDH. In one of the Pts. the ⁵¹Cr RBC T_1/2 survival increased from 12 to 16 days. The intracellular HbS polymer fractions (f_p) were determined at 25% O₂ by C_sat and with the use of the conservation of mass equation. The baseline f_p values ranged from 0.48–0.53. After iron restriction they ranged from 0.33–0.48. The f_p decreased even though iron-limited erythropoiesis also lowered the Hb F concentration in three of our Pts. In one of the two Pts. with induced iron depletion, hospitalization days for pain crises decreased from an average of 4.5 days/month (2 year baseline period) to an average of 0.5 days/month in the 3 year follow-up after iron depletion. The second patient with induced iron restriction experienced the rapid healing of a leg ulcer. Controlled iron restriction should be explored as a therapeutic strategy in selected SS patients. © 1994 Wiley-Liss, Inc.     

Iron-deficiency anemia, non-iron-deficiency anemia and HbA1c among adults in the US

Background: Conditions that affect erythrocyte turnover affect HbA1c concentrations. Although many forms of anemia are associated with lowering of HbA1c, iron deficiency tends to increase HbA1c. We examined the effect of iron and hemoglobin (Hb) status on HbA1c and on the relationship between concentrations of fasting glucose and HbA1c in a national sample of adults in the US. Methods: Cross‐sectional data from 8296 adults aged ≥20 years who participated in NHANES 1999–2002 were used. Results: The prevalence of low Hb (defined as <120 and <118 g/L in women aged 20–69 and ≥70 years, respectively, and <137, <133, and <124 g/L in men aged 20–49, 50–69, and ≥70 years, respectively) was 5.5%. There was a significant positive correlation between Hb concentrations and HbA1c concentrations after adjusting for age, gender, and race or ethnicity, with HbA1c rising from a mean of 5.28% among participants with Hb <100 g/L to 5.72% among participants with Hb ≥170 g/L. The adjusted mean concentrations of HbA1c were 5.56% and 5.46% among participants with and without iron deficiency, respectively (P = 0.095). However, there was no evidence of differences in the relationship between fasting glucose and HbA1c when groups of anemic and non‐anemic individuals with and without iron deficiency were examined individually. Conclusions: Caution should be used when diagnosing diabetes and prediabetes among people with high or low Hb when the HbA1c level is near 6.5% or 5.7%, respectively, as changes in erythrocyte turnover may alter the test result. However, the trend for HbA1c to increase with iron deficiency does not appear to require screening for iron deficiency in ascertaining the reliability of HbA1c in the diagnosis of diabetes and prediabetes in a given individual.     

Treatment of iron deficiency anemia associated with gastrointestinal tract diseases

The gastrointestinal (GI) tract is a common site of bleeding that may lead to iron deficiency anemia (IDA). Treatment of IDA depends on severity and acuity of patients’ signs and symptoms. While red blood cell transfusions may be required in hemodynamically unstable patients, transfusions should be avoided in chronically anemic patients due to their potential side effects and cost. Iron studies need to be performed after episodes of GI bleeding and stores need to be replenished before anemia develops. Oral ...     

Aplastic anemia associated with in vitro inhibition of erythropoiesis by bone marrow-adherent cells

A patient with aplastic anemia that evolved following pure red cell aplasia is described. Cultures of the patient's marrow cells revealed greatly reduced numbers of primitive (BFU-E) and relatively mature (CFU-E) erythroid progenitors, but normal numbers of multipotential (CFU-GEMM) precursors. The BFU-E/CFU-GEMM and CFU-E/BFU-E ratios in the patient's marrow cell cultures were also reduced. T cell- or antibody-mediated inhibition of in vitro erythropoiesis could not be demonstrated in this patient. However, the patient's marrow-adherent cells suppressed the growth of autologous and allogeneic BFU-E and CFU-E, without influencing the growth of CFU-GEMM. Medium conditioned by the patient's adherent cells failed to inhibit the growth of normal erythroid precursors. Our findings suggest a role for marrow-adherent cells in the pathogenesis of aplastic anemia in this patient.     

Correction of iron-deficient erythropoiesis in the treatment of anemia of chronic disease with recombinant human erythropoietin

Anemia of chronic disease (ACD) is a frequent complication of chronic inflammation in rheumatoid arthritis (RA). Recombinant human erythropoietin (rHuEpo) has been shown to be effective in correcting ACD, although with a variable rate of nonresponders. The first aim of this trial was to improve the response to rHuEpo by parenteral iron supplementation in cases of iron-deficient erythropoiesis (IDE). An additional goal was the evaluation of the zinc protoporphyrin content of erythrocytes (ZnPP), the soluble transferrin receptor (sTrfR) serum concentration, and the hemoglobin (Hb) content of reticulocytes (CHr) in stimulated erythropoiesis as diagnostic and prognostic parameters. Thirty RA patients with ACD were treated with subcutaneous 150 IU rHuEpo/kg body weight twice weekly. Intravenous iron supplementation (200 mg iron sucrose once weekly) was added in cases of IDE (n=23), which was defined by the presence of two of three criteria: saturation of transferrin (TrfS) 15%, hypochromic erythrocytes (HypoE) 10%, and a serum ferritin (Fn) concentration 50 g/l. All 28 completers met the treatment goal, with an increase of the median Hb concentration from 10.3 g/dl to 13.3 g/dl. Epo treatment and iron supplementation was safe and well tolerated in all patients. Monitoring of Fn, TrfS, and HypoE every other week allowed a successful correction of anemia. Retrospective analysis of the evaluable parameters (CHr, sTrfR, and ZnPP) revealed no additional benefit for predicting or monitoring IDE in this setting, although the one or other may be advantageous in other therapeutic situations.     

A child with severe iron-deficiency anemia and a complex TMPRSS6 genotype

Objectives: We report a case of a 7-year-old girl with severe hypochromic microcytic anemia, who was unresponsive to classical iron supplements. We suspected IRIDA, iron-refractory iron-deficiency anemia, a genetic iron metabolism disorder, caused by TMPRSS6 variations. TMPRSS6 encodes matriptase-2, a negative regulator of hepcidin, and its pathological variants are related to normal to high levels of hepcidin. We analyzed the TMPRSS6 gene and we improved clinical management of the patient, selecting the appropriate supplementation therapy.

Intervention & Technique: The parenteral iron therapy was started, but the patient was only partially responsive and the anemia persisted. To confirm the diagnosis, the TMPRSS6 gene sequence was analyzed by DNA sequencing and other relevant biochemical parameters were evaluated.

Results: The TMPRSS6 sequence analysis showed a complex genotype with a rare heterozygous missense variant, in addition to other common polymorphisms. The serum hepcidin value was normal. We unexpectedly observed a normalization of patient’s hemoglobin (Hb) levels only after liposomal iron treatment.

Discussion and Conclusion: The proband was symptomatic for IRIDA during a critical phase of growth and development, but we did not find a clearly causative genotype. A long-term result, improving stably patient’s Hb levels, was obtained only after liposomal iron supplementation. Children may be at greater risk for iron deficiency and the degree of anemia as well as the response to the iron supplements varies markedly patient to patient. Here, we show the importance of comprehensive study of these patients in order to collect useful information about genotype–phenotype association of genes involved in iron metabolism.     

Suppression of erythropoiesis in malarial anemia is associated with hemozoin in vitro and in vivo

Malarial anemia is a global public health problem and is characterized by a low reticulocyte response in the presence of life-threatening hemolysis. Although cytokines, in particular tumor necrosis factor-alpha (TNF-alpha), can suppress erythropoiesis, the grossly abnormal bone marrow morphology indicates that other factors may contribute to ineffective erythropoiesis. We hypothesized that the cytotoxic hemozoin (Hz) residues from digested hemoglobin (Hb) significantly contribute to abnormal erythropoiesis. Here, we show that not only isolated Hz, but also delipidated Hz, inhibits erythroid development in vitro in the absence of TNF-alpha. However, when added to cultures, TNF-alpha synergizes with Hz to inhibit erythropoiesis. Furthermore, we show that, in children with malarial anemia, the proportion of circulating monocytes containing Hz is associated with anemia (P < .001) and reticulocyte suppression (P = .009), and that this is independent of the level of circulating cytokines, including TNF-alpha. Plasma Hz is also associated with anemia (P < .001) and reticulocyte suppression (P = .02). Finally, histologic examination of the bone marrow of children who have died from malaria shows that pigmented erythroid and myeloid precursors are associated with the degree of abnormal erythroid development. Taken together, these observations provide compelling evidence for inhibition of erythropoiesis by Hz.     

Evaluation of bone marrow iron stores in anemia associated with chronic disease: A comparative study of serum and red cell ferritin

The serum ferritin (SERFER) may be elevated and misleading in the setting of chronic disease (chronic inflammation, liver disease, and neoplasm). The red cell ferritin (RBCFER) may be more stable in clinical situations that affect the SERFER. We compared the ability of SERFER and RBCFER to assess iron stores in these settings. Iron stores were defined by bone marrow aspirate staining. We studied 120 anemic (Hb < 14 g/dl) male patients. Twenty-eight (23%) were iron deficient based on the absence of marrow iron. The SERFER correlation with marrow iron stores (r = 0.58; P < 0.001) was better than the RBCFER (r = 0.36; P < 0.001). Cutoff values for the diagnosis of iron deficiency were determined by chi-square analysis (SERFER < 70 ng/ml; RBCFER ± 4 ag/RBC). The sensitivity for detecting iron deficiency with SERFER (0.60) was less than RBCFER (0.82). The specificity of SERFER (0.90) was slightly better than RBCFER (0.83). Neither difference reached statistical significance (P > 0.05). The positive predictive value between the two assays was the same (SERFER 0.65 vs. RBCFER 0.59). The combination of SERFER <70 ng/ml with RBCFER ≤ 4 ag/RBC was more specific (0.97) when compared with the SERFER alone (0.90) (P = 0.04). In addition, the potential of this combination to predict iron deficiency (0.82) was higher than that seen with either SERFER (0.65) or the RBCFER (0.59). Our findings show that the RBCFER as a single assay is not anymore accurate than the SERFER. However, we find that the RBCFER can effectively complement the SERFER to either predict iron depletion or confirm the presence of bone marrow iron. © 1993 Wiley-Liss, Inc.     

Advances in understanding iron metabolism and its crosstalk with erythropoiesis

Recent years have witnessed impressive advances in our understanding of iron metabolism. A number of studies of iron disorders and of their animal models have provided landmark insights into the mechanisms of iron trafficking, distribution and homeostatic regulation, the latter essential to prevent both iron deficiency and iron excess. Our perception of iron metabolism has been completely changed by an improved definition of cellular and systemic iron homeostasis, of the molecular pathogenesis of iron disorders, the fine tuning of the iron hormone hepcidin by activators and inhibitors and the dissection of the components of the hepcidin regulatory pathway. Important for haematology, the crosstalk of erythropoiesis, the most important iron consumer, and the hepcidin pathway has been at least partially clarified. Novel potential biomarkers are available and novel therapeutic targets for iron‐related disorders have been tested in murine models. These preclinical studies provided proofs of principle and are laying the ground for clinical trials. Understanding iron control in tissues other than erythropoiesis remains a challenge for the future.     

Stimulating erythropoiesis in inflammatory bowel disease associated anemia

Anemia is a frequent complication in patients with inflammatory bowel disease (IBD), and is associated with decreased quality of life and increased rate of hospitalization. The primary therapeutic targets of IBD- associated anemia are iron deficiency and anemia of chronic disease. An important prognostic parameter of the success or failure of therapy is the outcome of the underlying disease. Iron deficiency should be appropriately managed with iron supplementation. However, the use of oral iron therapy is limited by several problems, the most important being gastrointestinal side effects leading occasionally to disease relapse and poor iron absorption. Intravenous iron preparations are more reliable, with iron sucrose demonstrating the best efficacy and tolerability. Treatment with erythropoietin or darbepoetin has been proven to be effective in patients with anemia, who fail to respond to intravenous iron. Patients with ongoing inflammation have anemia of chronic disease and may require combination therapy comprising of intravenous iron sucrose and erythropoietin. After initiating treatment, careful monitoring of hemoglobin levels and iron parameters is needed in order to avoid recurrence of anemia. In conclusion, anemia in the setting of IBD should be aggressively diagnosed, investigated, and treated. Future studies should define the optimal dose and schedule of intravenous iron supplementation and appropriate erythropoietin therapy in these patients.     

Prevalence of iron deficiency anemia and iron deficiency in a pediatric population with inflammatory bowel disease

Objectives: Iron deficiency is the most common cause of anemia in children with inflammatory bowel disease, although the real prevalence is unknown. Intravenous iron is suggested as the first line treatment. This study aims to determine the prevalence of iron deficiency anemia in children with inflammatory bowel disease followed in a Pediatric Gastroenterology Unit of a tertiary center and to evaluate this unit's experience with intravenous iron.

Materials and methods: A retrospective cohort study was designed involving children with inflammatory bowel disease followed in that unit between January 2001 and April 2016. Laboratory results were collected at the moment of diagnosis, after one-year follow-up and prior each IV iron administration performed during the study period. Anemia was defined according to World Health Organization criteria and the iron deficiency was defined using recent guidelines.

Results: Were studied 69 patients 71% had CD and 29% UC. 50.7% were female. Mean patient age at diagnosis was 13.3 years (range 1--17 years). Prevalence of ID and IDA at diagnosis was 76.8% and 43.5%, respectively. After one year follow-up, those values decreased to 68.1% (p?=?.182) and 21.7% (p?=?.002), respectively. Hemoglobin significantly increased (p?<?.001). Intravenous iron was administered to 92.8% of patients. No adverse reactions were reported.

Conclusions: Intravenous iron is the first line in the treatment of Iron deficiency anemia in Inflammatory Bowel disease and it is safe and effective. Persistent anemia and iron deficiency are common.     

Gastrointestinal endoscopic findings in men with unexplained anemia and low normal ferritin values

BACKGROUND: Most practice guidelines recommend endoscopic evaluation of the gastrointestinal (GI) tract in men and postmenopausal women with anemia and a serum ferritin less than 20-40 ng/ml. The diagnostic yield of endoscopy in patients with anemia, no GI symptoms or signs, and low normal ferritin is not known. OBJECTIVE: The aim of this study was to investigate the yield of upper and lower GI endoscopic evaluations in anemic patients with ferritin levels between 40 and 100 ng/ml. DESIGN: A retrospective review of patients' charts was conducted. SUBJECTS AND METHODS: Patients at the Veterans Affairs Connecticut Healthcare System who underwent GI endoscopic evaluation for the sole indication of anemia and ferritin in the low normal range (40-100 ng/ml) were included in this study. MEASUREMENTS: Incidence of pathology of the upper and lower GI tract was determined. RESULTS: We identified 54 male patients who had a ferritin level of 40-100 ng/ml and no GI symptoms or known GI bleeding. Upper GI findings (malignancy, peptic ulcers, Helicobacter pylori gastritis, arteriovenous malformations) were found in 14/47 cases (30%). Lower gastrointestinal findings, including large tubular adenomas and arteriovenous malformation, were identified in 3/53 cases (6.7%). CONCLUSION: Our study supports GI endoscopy in anemic patients with ferritin between 40 and 100 ng/ml, even in the absence of GI symptoms or documented bleeding.     

Congenital 6-phosphogluconate dehydrogenase (6PGD) deficiency associated with chronic hemolytic anemia in a Spanish family

Clinical and metabolic studies were performed in four members of a Spanish family with partial (50%) 6 phosphogluconate dehydrogenase (6PGD) deficiency. In all cases the activities of 6 phosphogluconolactone (6PGL) and glutathione reductase (GR) were normal, and the molecular characterization performed in the partially purified 6PGD from the propositus showed normal kinetic and electrophoretic patterns. Two females (the propositus and her sister) suffered from a well-compensated chronic nonspherocytic hemolytic anemia (CNSHA) and exhibited decreased RBC glutathione (GSH) stability with increased oxidative susceptibility, defined by enhanced malonyldialdehyde (MDA) generation “in vitro.” The other two members of the family (the propositus's mother and brother) were clinically asymptomatic. In the propositus and her sister, RBC metabolism exhibited a markedly abnormal concentration of glycolytic intermediates, mainly characterized by striking increases in fructose 1,6 bisphosphate (50-fold), dihydroxiacetone-phosphate (20-fold) and glyceraldehyde 3-phosphate (tenfold). Although the precise mechanism of the hemolysis in the two patients is unknown, the enhanced oxidative threat observed in their RBCs may interfere in some way with the glycolytic pathway function, leading to a marked increase in certain metabolic intermediates located before the glyceraldehyde 3 phosphate dehydrogenase (GA3PD) step. Since it seems that GA3PD half-life is modulated by fluctuations of the cytosolic redox status, an “in situ” approach was simulated by using permeabilized RBCs. In these conditions, GA3PD activity was significantly lower in the propositus and her sister than in the asymptomatic members of the family and the simultaneous normal control. © 1996 Wiley-Liss, Inc.     

Circulating cytokines response and the level of erythropoiesis in sickle cell anemia

A hemoglobin F (HbF) level between eight and nine percent divides sickle cell anemia (SS) patients into two populations, according to the kinetics of circulating burst forming units-erythroid (BFU-E), long term culture-initialing cells (LTC-IC), and cytokine plasma concentrations. The SS patients with HbF levels lower than 8–9% are more anemic (LFSS patients) than those with HbF levels higher than 8–9% who have less severe anemia (HFSS patients). We report here that the level of erythropoiesis [evaluated by the levels of soluble transferin receptors (sTfR)] is not identical in these two patient populations, supporting the idea that a different set of regulatory mechanisms might be required to maintain the two levels of increased hematopoiesis. The plasma sTfR concentration was increased in all SS samples compared with controls (P < 0.002) and sTfR levels were negatively correlated with peripheral HbF%. (r = −0.574, P < 0.002). Furthermore, sTfR levels were higher in LFSS than in HFSS patients. Erythropoietin (Epo) levels were increased in the plasma of LFSS individuals (range = 34–215 ml U/ml), while the values in HFSS patients were in the normal range (3–20 ml U/ml). Furthermore, we identify here stem cell factor (SCF) and transforming growth factor-β (TGF-β) as regulatory factors specifically affected by the presence of SS genotype and its level of severity. The plasma concentrations of SCF and TGF-β were increased compared with normal controls and high levels of SCF (up to 7,000 pg/ml) were detected in LFSS patients. The latter also showed increased proportion of SCF⁺ CD³⁴ enriched circulating cells (49%). Low SCF in HFSS patients is associated with elevated TGF-β, suggesting a regulatory role of the latter on either SCF release or c-kit expression in progenitor cells. Occasional elevation of granulocyte macrophage-colony stimulating factor (G-CSF), interleukin (IL)-7, and macrophage inflammatory protein (MIP)-1α in plasma of SS patients is not specific because no relation to HbF could be demonstrated. All plasma tested for leukemia inhibitory factor (LIF) were negative. Data presented here, complementing previously published information, supports a model in which HFSS patients achieve a balance between inhibitory (TGF-β) and stimulatory (SCF, IL-3) factors, resulting in moderate erythropoietic response. In contrast, in LFSS patients, low levels of TGF-β and the increased release of GM-CSF and SCF maintain the intense erythropoiesis in response to higher erythropoietic stress, in these more severe patients. Am. J. Hematol. 60:105–115, 1999. © 1999 Wiley-Liss, Inc.     

Heme inhibits cartilage metabolism and growth in vitro

The present study was designed to investigate the potential role of heme as a direct inhibitor of cartilage metabolism and growth. We used the embryonic chick pelvic rudiment bioassays and the hypophysectomized rat cartilage sulfation bioassay, both sensitive to growth factors and growth inhibitors. In the chick bioassay pelvic rudiment growth was inhibited when heme was added to the culture medium at 0.1 mmol/L (after five days in culture, cartilage weight 224% +/- 11% of initial with normal serum, but 141% +/- 3% of initial with serum plus heme 0.25 mmol/L); the heme-induced growth inhibition was promptly reversible when cartilages were placed in heme-free medium. This was due, at least in part, to heme-induced inhibition of (1) [35S] sulfate incorporation into proteoglycans by as little as 0.05 mmol/L heme (66% +/- 5% of assay buffer); (2) [14C] leucine incorporation into proteins by greater than or equal to 0.05 mmol/L heme (85% +/- 6% of assay buffer); and (3) [3H] uridine incorporation by greater than or equal to 0.10 mmol/L heme (50% +/- 4% of assay buffer). In the rat cartilage sulfation bioassay (the literature "standard" bioassay for skeletal growth studies) a dose-dependent inhibition of [35S] sulfate incorporation occurred with greater than or equal to 0.01 mmol/L added heme (82% +/- 3% of assay buffer). Heme caused a dose-dependent and reversible inhibition of cartilage metabolism and growth, and it may have a novel role in the pathophysiology of growth retardation associated with some chronic disease.     

Platelet counts in adults with iron deficiency anemia

In adults with iron deficiency anemia (IDA), abnormal platelet counts were seen in several studies. However we retrospectively examined the clinical records of a larger number of adults with IDA to assess abnormal platelet counts. From November 2006 to April 2008, 615 consecutive adults (73 men and 542 women; age range, 16–88 years) with IDA were included in this study. The mean initial hemoglobin was 9.0 ± 1.8 g/dL (range 2.7–12.8 g/dL), and the mean initial platelet count was 304 × 10³/µL ± 92.3 (range, 105–700 × 10³/µL). The initial platelet counts were normal in 520 (84.6%) adults with IDA. Thrombocytosis (>400 × 10³/µL) and thrombocytopenia (<150 × 10³/µL) were detected in 82 (13.3%) and 13 (2.1%) adults with IDA, respectively. In conclusion, thrombocytosis was seen at lower rates in our study. Furthermore, this study shows that mild thrombocytopenia is not so rare in adults with IDA.     

Evaluation of microcytosis using serum ferritin and red blood cell distribution width

Out of 104 patients with microcytosis (MCV less than 80 fl), 69% had an iron deficiency, 21% a chronic disease and 10% hemoglobinopathy or thalassemia trait. The absence of bone marrow iron stores or the response to iron supplementation were used to establish the diagnosis iron deficiency. On the basis of sensitivity (90%) and specificity (100%), the serum ferritin concentration is more suitable for assessment of iron deficiency than the serum iron concentration, the total iron-binding capacity or the percentual saturation of transferrin. The red cell distribution width (RDW) is the parameter with the highest sensitivity for iron deficiency (94%). An RDW value within the reference interval can be used to exclude iron deficiency in those cases in which the serum ferritin concentration does not accurately reflect the iron stores owing to severe tissue damage, as in inflammation or malignancy.     

The role of iron repletion in adult iron deficiency anemia and other diseases

Iron deficiency anemia (IDA) is the most prevalent and treatable form of anemia worldwide. The clinical management of patients with IDA requires a comprehensive understanding of the many etiologies that can lead to iron deficiency including pregnancy, blood loss, renal disease, heavy menstrual bleeding, inflammatory bowel disease, bariatric surgery, or extremely rare genetic disorders. The treatment landscape for many causes of IDA is currently shifting toward more abundant use of intravenous (IV) iron due to its effectiveness and improved formulations that decrease the likelihood of adverse effects. IV iron has found applications beyond treatment of IDA, and there is accruing data about its efficacy in patients with heart failure, restless leg syndrome, fatigue, and prevention of acute mountain sickness. This review provides a framework to diagnose, manage, and treat patients presenting with IDA and discusses other conditions that benefit from iron supplementation.