Pathophysiology of Transfusional Iron Overload: Contrasting Patterns in Thalassemia Major and Sickle Cell Disease

Hemoglobin ◽  
2009 ◽  
Vol 33 (sup1) ◽  
pp. S37-S45 ◽  
Author(s):  
John B. Porter
Keyword(s):  
Sickle Cell Disease ◽  
Iron Overload ◽  
Sickle Cell ◽  
Thalassemia Major ◽  
Cell Disease

Consequences and management of iron overload in sickle cell disease

Hematology ◽  
2013 ◽  
Vol 2013 (1) ◽  
pp. 447-456 ◽  
Author(s):  
John Porter ◽  
Maciej Garbowski
Keyword(s):  
Sickle Cell Disease ◽  
Blood Transfusion ◽  
Iron Overload ◽  
Sickle Cell ◽  
Iron Concentration ◽  
Thalassemia Major ◽  
Iron Loading ◽  
Cell Disease ◽  
Liver Iron Concentration ◽  
Liver Iron

Abstract The aims of this review are to highlight the mechanisms and consequences of iron distribution that are most relevant to transfused sickle cell disease (SCD) patients and to address the particular challenges in the monitoring and treatment of iron overload. In contrast to many inherited anemias, in SCD, iron overload does not occur without blood transfusion. The rate of iron loading in SCD depends on the blood transfusion regime: with simple hypertransfusion regimes, rates approximate to thalassemia major, but iron loading can be minimal with automated erythrocyte apheresis. The consequences of transfusional iron overload largely reflect the distribution of storage iron. In SCD, a lower proportion of transfused iron distributes extrahepatically and occurs later than in thalassemia major, so complications of iron overload to the heart and endocrine system are less common. We discuss the mechanisms by which these differences may be mediated. Treatment with iron chelation and monitoring of transfusional iron overload in SCD aim principally at controlling liver iron, thereby reducing the risk of cirrhosis and hepatocellular carcinoma. Monitoring of liver iron concentration pretreatment and in response to chelation can be estimated using serum ferritin, but noninvasive measurement of liver iron concentration using validated and widely available MRI techniques reduces the risk of under- or overtreatment. The optimal use of chelation regimes to achieve these goals is described.

scholarly journals Hidden Brain iron content in Sickle cell disease: Impact on Neurocognitive Functions

2021 ◽  
Author(s):  
Mohsen Saleh ElAlfy ◽  
Ahmed Samir Ibrahim ◽  
Ghada Samir Ibrahim ◽  
Hanaa Midhat Abdel Gader Hussein ◽  
Hend Galal Eldeen Mohammed ◽  
...  
Keyword(s):  
Sickle Cell Disease ◽  
Iron Overload ◽  
Sickle Cell ◽  
Brain Mri ◽  
Thalassemia Major ◽  
Beta Thalassemia ◽  
Brain Iron ◽  
Cell Disease ◽  
Neurocognitive Dysfunction ◽  
Neurocognitive Functions

Abstract Children with sickle cell disease (SCD) are at a high risk for neurocognitive impairment. We aim to quantitatively measure cerebral tissue R2* to investigate the brain iron deposition in children and young adults with SCD in comparison to beta thalassemia major (BTM) and healthy controls and evaluate its impact on neurocognitive functions in patients with SCD. Thirty-two SCD, fifteen BTM and eleven controls were recruited. Multi-echo fast-gradient echo sequence brain MRI was performed and brain R2* values of both caudate and thalamic regions were calculated. SCD patients were examined for the neurocognitive functions. SCD had high iron overload 0.30±0.12 mg/kg/day. 68.9% of SCD had under- threshold IQ, 12.5% had moderate to severe anxiety and 60.8% had depression. There was no differences between SCD, BTM and controls in brain MRI except that left thalamus R2* higher in BTM than both SCD and controls (p=0.032). Mean right caudate R2* was higher in female than male (p=0.044). No significant association between brain R2* and LIC or heart R2* values in SCD. Left caudate R2* directly correlate with age and HbS%, negative correlate with HbA% while right thalamus R2* negatively correlate with transfusion index and among SCD patients. Conclusion: Neurocognitive dysfunction in SCD could not be explained solely by brain iron overload.

Cardiac Iron Overload In Sickle-Cell Disease

Blood ◽  
2013 ◽  
Vol 122 (21) ◽  
pp. 1013-1013
Author(s):  
Antonella Meloni ◽  
Mammen Puliyel ◽  
Alessia Pepe ◽  
Massimo Lombardi ◽  
Vasilios Berdoukas ◽  
...  
Keyword(s):  
Myocardial Infarction ◽  
Sickle Cell Disease ◽  
Iron Overload ◽  
Sickle Cell ◽  
Clinical Characteristics ◽  
Transferrin Saturation ◽  
Thalassemia Major ◽  
Cell Disease ◽  
Cardiac Iron ◽  
Cardiac Iron Overload

Abstract Introduction Chronically transfused sickle cell disease (SCD) patients have lower risk of endocrine and cardiac iron overload load than comparably transfused thalassemia major patients. The mechanisms for this protection remain controversial but likely reflects lower transferrin saturation and circulating labile iron pools because of chronic inflammation and regeneration of apotransferrin through erythropoiesis. However, cardioprotection is incomplete; we have identified 6 patients out of the 201 patients (3%) followed at our Institution who have prospectively developed cardiac iron. We present the clinical characteristics of these patients to identify potential risk factors for cardiac iron accumulation. Methods Cardiac, hepatic, and pancreatic iron overload were assessed by R2* Magnetic Resonance Imaging (MRI) techniques as extensively described by our laboratory. The medical records of the selected patients were reviewed for demographic data, for transfusion and chelation history and for hematologic and biochemical parameters. Results Table 1 describes clinical characteristics of the six patients at the time they developed detectable cardiac iron (R2* ≥ 50 ms). Patient 6 was included because he showed a R2* of 49 Hz that was increasing rapidly. Five of the six patients were managed on simple transfusions. Five patients had been on chronic transfusion for more than 11 years. The three patients who developed cardiac iron the earliest (3.7 – 14 years of transfusions) had more efficient suppression of endogenous red cell production (HbS levels 2-5%) compared with patients who required longer transfusional exposure (HbS levels 13.3 – 41%). All patients had qualitatively poor chelation compliance (<50%), based upon their prescription refill rate. All patients had serum ferritin levels exceeding 4600 and liver iron concentration (LIC) greater than 22 mg/g. Pancreatic R2* was greater than 100 Hz in every patient studied (5/6). Figure 1 shows the longitudinal relationship between iron overload in the heart and in the other organs for each patient; initial iron levels are shown in black. Cardiac R2* appears increase dramatically once a critical LIC “threshold” is reached, qualitatively similar to the 18 mg/g threshold observed in thalassemia major patients. Cardiac R2* rose proportionally to pancreas R2*, similar to thalassemia major patients, with all of the patients having pancreas R2* > 100 Hz at the time cardiac iron was detected. Conclusions Cardiac iron overload occurs in a small percentage of chronically transfused SCD patients and is only associated with exceptionally poor control of total body iron stores. Duration of chronic transfusion is clearly important but other factors, such as levels of effective erythropoiesis, may also contribute to cardiac risk. The relationship between cardiac iron and pancreas R2* suggests that pancreas R2* can serve as a valuable screening tool for cardiac iron in SCD patients. Disclosures: Berdoukas: ApoPharma inc: Consultancy. Coates:ApoPharma inc, Novartis, Shire: Consultancy. Wood:Novartis: Consultancy, Honoraria; Shire: Consultancy, Research Funding; ApoPharma: Consultancy, Honoraria, Use of deferiprone in myocardial infarction, Use of deferiprone in myocardial infarction Patents & Royalties.

Growth differentiation factor-15 in young sickle cell disease patients: Relation to hemolysis, iron overload and vascular complications

2014 ◽  
Vol 53 (4) ◽  
pp. 189-193 ◽  
Author(s):  
Azza Abdel Gawad Tantawy ◽  
Amira Abdel Moneam Adly ◽  
Eman Abdel Rahman Ismail ◽  
Yasser Wagih Darwish ◽  
Marwa Ali Zedan
Keyword(s):  
Sickle Cell Disease ◽  
Iron Overload ◽  
Sickle Cell ◽  
Vascular Complications ◽  
Cell Disease ◽  
Growth Differentiation Factor 15 ◽  
Differentiation Factor

scholarly journals Serum ferritin and total units transfused for assessing iron overload in adults with sickle cell disease

2012 ◽  
Vol 157 (5) ◽  
pp. 645-647 ◽  
Author(s):  
Emma Drasar ◽  
Nisha Vasavda ◽  
Norris Igbineweka ◽  
Moji Awogbade ◽  
Marlene Allman ◽  
...  
Keyword(s):  
Sickle Cell Disease ◽  
Iron Overload ◽  
Sickle Cell ◽  
Serum Ferritin ◽  
Cell Disease

scholarly journals American Society of Hematology 2020 guidelines for sickle cell disease: transfusion support

2020 ◽  
Vol 4 (2) ◽  
pp. 327-355 ◽  
Author(s):  
Stella T. Chou ◽  
Mouaz Alsawas ◽  
Ross M. Fasano ◽  
Joshua J. Field ◽  
Jeanne E. Hendrickson ◽  
...  
Keyword(s):  
Sickle Cell Disease ◽  
Iron Overload ◽  
Sickle Cell ◽  
Conflicts Of Interest ◽  
Guideline Development ◽  
Practice Research ◽  
Evidence Based ◽  
Red Cell ◽  
Cell Disease ◽  
American Society

Background: Red cell transfusions remain a mainstay of therapy for patients with sickle cell disease (SCD), but pose significant clinical challenges. Guidance for specific indications and administration of transfusion, as well as screening, prevention, and management of alloimmunization, delayed hemolytic transfusion reactions (DHTRs), and iron overload may improve outcomes. Objective: Our objective was to develop evidence-based guidelines to support patients, clinicians, and other healthcare professionals in their decisions about transfusion support for SCD and the management of transfusion-related complications. Methods: The American Society of Hematology formed a multidisciplinary panel that was balanced to minimize bias from conflicts of interest and that included a patient representative. The panel prioritized clinical questions and outcomes. The Mayo Clinic Evidence-Based Practice Research Program supported the guideline development process. The Grading of Recommendations Assessment, Development and Evaluation (GRADE) approach was used to form recommendations, which were subject to public comment. Results: The panel developed 10 recommendations focused on red cell antigen typing and matching, indications, and mode of administration (simple vs red cell exchange), as well as screening, prevention, and management of alloimmunization, DHTRs, and iron overload. Conclusions: The majority of panel recommendations were conditional due to the paucity of direct, high-certainty evidence for outcomes of interest. Research priorities were identified, including prospective studies to understand the role of serologic vs genotypic red cell matching, the mechanism of HTRs resulting from specific alloantigens to inform therapy, the role and timing of regular transfusions during pregnancy for women, and the optimal treatment of transfusional iron overload in SCD.

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