Serum Ferritin a Predictor of Iron Overload in Patients with Thalassemia and Sickle Cell Disease?.

Blood ◽  
2004 ◽  
Vol 104 (11) ◽  
pp. 3789-3789 ◽  
Author(s):  
Zahra Pakbaz ◽  
Roland Fischer ◽  
Richard Gamino ◽  
Ellen B. Fung ◽  
Paul Harmatz ◽  
...  
Keyword(s):  
Sickle Cell Disease ◽  
Iron Overload ◽  
Sickle Cell ◽  
Serum Ferritin ◽  
Iron Concentration ◽  
Cell Disease ◽  
Liver Iron Concentration ◽  
Liver Iron ◽  
Iron Stores ◽  
Significant Difference

Abstract Introduction: Monitoring iron overload by serum ferritin in patients with hemosiderosis is still a routine practice although its limitations are widely studied and well known. Using non-invasive liver iron assessment by quantitative MRI or by biomagnetic liver susceptometry (BLS) with SQUID biomagnetometers would be the better alternative, however, these methods are available at only a few centers worldwide. Objective: To determine the relationship between serum ferritin (SF) and liver iron concentration (LIC), measured by BLS at CHRCO, in patients with different types of hemosiderosis. Methods and Patients: A total of 97 patients with thalassemia (TM: 3 to 52 y, 54% females) and 39 patients with sickle cell disease (SCD: 5 to 49 y, 60% female) were prospectively assessed for LIC and SF. Both tests were performed within 2 weeks of each other. Most patients with TM and SCD were chronically transfused, while 10 b-thalassemia intermedia (TI), 5 HbE/β-thalassemia (HbE), and 5 SCD patients were not on transfusion programs. LIC was measured by LTc SQUID biosusceptometer system (Ferritometer®, Model 5700, Tristan Technologies, San Diego, USA) under the standardized Hamburg-Torino-Oakland protocol. A non-parametric test (U-test) was utilized to analyze differences between SF and LIC data. Results: In chronically transfused TM and SCD patients, the median SF and LIC were very similar (Table I). In TI&HbE patients, ferritin results were disproportionately low with respect to LIC. In order to improve prediction of iron stores by SF, the SF/LIC ratio was calculated. There was a significant difference between the median ratios of the two groups of transfused and non- transfused thalassemia patients, 0.82 vs. 0.32 [μg/l]/[μg/gliver], respectively (p < 0.01). In SCD patients the ratio is significantly (p < 0.01) higher. Conclusion: Present data confirm ferritin to be a poor predictor of liver iron stores both in sickle cell disease and thalassemia. Relying only on ferritin to monitor iron overload in patients with hemosiderosis can be misleading, especially, in sickle cell disease and non-transfused thalassemia patients. Taking into account disease specific ferritin-LIC relations, could improve the prediction of iron stores. However, assessment of liver iron stores is the ultimate method to initiate and adjust chelation treatment in order to avoid progressive organ injury. Table I. Median values and ranges ( − ) of serum ferritin (SF) and liver iron concentration (LIC) in transfused (Tx) and non-transfused (non-Tx) hemosiderosis patients. Patient group n SF μg/l] LIC [mg/gliver ] SF:LIC Thalassemia Tx 82 1721 (209–8867) 3424 (364–7570) 0.82 (0.3–1.8) TI &HbE non-Tx 15 766 (52–2681) 2174 (226–5498) 0.32 (0.1–1.4) SCD Tx 34 2757 (400–9138) 1941 (518–6670) 1.2 (0.6–3.3)

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.

Liver Transient Elastography (FibroScan) Correlates with Liver Iron Concentration and Reflects Liver Fibrosis In Patients with Sickle Cell Disease

Blood ◽  
2010 ◽  
Vol 116 (21) ◽  
pp. 1646-1646 ◽  
Author(s):  
Ersi Voskaridou ◽  
Maria Schina ◽  
Eleni Plata ◽  
Dimitrios Christoulas ◽  
Maria Tsalkani ◽  
...  
Keyword(s):  
Liver Fibrosis ◽  
Iron Overload ◽  
Hepatic Fibrosis ◽  
Sickle Cell ◽  
Serum Ferritin ◽  
Transient Elastography ◽  
Iron Concentration ◽  
Liver Stiffness ◽  
Cell Disease ◽  
Liver Iron

Abstract Abstract 1646 Liver transient elastography (FibroScan) is an interesting new technology that allows estimation of hepatic fibrosis through measurement of liver stiffness. The technique is based on changes in tissue elasticity induced by hepatic fibrosis and is considered as a noninvasive, reproducible and reliable method to assess hepatic fibrosis as well as to diagnose liver cirrhosis. Hepatic iron overload is a severe complication of chronic transfusion therapy in patients with hemoglobinopathies and plays an important role in the development of hepatic fibrosis and cirrhosis. Iron overload is present in several cases of sickle cell disease (SCD) including sickle cell anemia (HbS/HbS) and double heterozygous sickle-cell/beta-thalassemia (HbS/beta-thal). The aim of the study was to evaluate liver fibrosis by measuring the liver rigidity (Liver Stiffness Measurement, LSM, kPascals) using transient elastography (FibroScan, Echosens, Paris, France) in patients with SCD and explore possible correlations with clinical and laboratory characteristics of the patients, including iron overload. We studied 110 consecutive patients with SCD who are followed-up in the Thalassemia Center of Laikon General Hospital in Athens, Greece. Forty-four patients were males and 66 females; their median age was 44 years (range: 21–73 years). Twenty-two patients had HbS/HbS and 88 patients had HbS/beta-thal. On the day of Fibroscan, all patients had a thorough hematology and biochemical evaluation, including hemoglobin, reticulocyte counts, serum ferritin, liver biochemistry, bilirubin, lactate dehydrogenase (LDH) and serology for viral hepatitis. Liver iron concentration was evaluated by magnetic resonance imaging (MRI) T2* in all patients. The median LSM of all patients was 6.1 kPascals (range: 3.4–48.8 kPascals) with no differences between HbS/HbS (6.1 kPascals, 3.5–17.3 kPascals) and HbS/beta-thal (6.1 kPascals, 3.4–48.8 kPascals) patients (p=0.835). LSM values strongly correlated with liver MRI T2* values (r=0.337, p<0.001), serum ferritin (r=0.328, p=0.001), number of transfusions (r=0.332, p=0.001), bilirubin (r=0.299, p=0.003), LDH (r=0.287, p=0.004), Hb (r=-0.275, p=0.006) and reticulocyte counts (r=0.244, p=0.015). LSM values showed also strong positive correlations with biochemical indicators of liver function: gamma-glutamyl transpeptidase (r=0.522, p<0.0001), glutamic oxaloacetic transaminase (r=0.484, p<0.0001), glutamic pyruvic transaminase (r=0.422, p<0.0001), alkaline phosphatase (r=0.334, p=0.001), gamma-globulin (r=0.296, p=0.005) and weak correlation with PT-International Normalized Ratio (r=0.184, p=0.094). The above correlations were similar in patients with HbS/HbS and in patients with HbS/beta-thal. However, in HbS/HbS patients the correlation between LSM and liver T2* values was very strong (r=0.770, p=0.001). Patients who were regularly transfused had higher values of LSM (median: 6.7 kPascals, range: 2.3–48.8 kPascals) compared with patients who were sporadically transfused or were not transfused (4.4 kPascals, 3.6–17.5 kPascals, p=0.003). Patients who were under iron chelation therapy had lower values of LSM (6.3 kPascals, 3.4–15 kPascals) compared with those who did not receive iron chelators (13.9 kPascals, 8.5–17.3 kPascals, p=0.013). We found no correlations between the presence of HBV or HCV positivity and the levels of LSM. In conclusion, FibroScan may constitute a reliable and easy to apply noninvasive method to assess liver fibrosis in patients with SCD; the strong correlations between LSM values with MRI T2* values and serum ferritin supports this observation. Furthermore, FibroScan seems also to reflect the presence of chronic hepatic injury in these patients. If our results are confirmed by other studies, FibroScan may be regularly used in the management of SCD patients in whom liver is the main target organ of the disease. Disclosures: No relevant conflicts of interest to declare.

Serum Ferritin in Children with Sickle Cell Disease on Chronic Transfusion: Measure of Iron Overload or End Organ Injury? STOP/STOP II Liver Iron Ancillary Study.

Blood ◽  
2006 ◽  
Vol 108 (11) ◽  
pp. 791-791 ◽  
Author(s):  
Tom Adamkiewicz ◽  
Miguel R. Abboud ◽  
Julio C. Barredo ◽  
Melanie Kirby-Allen ◽  
Ofelia A. Alvarez ◽  
...  
Keyword(s):  
Sickle Cell Disease ◽  
Iron Overload ◽  
Sickle Cell ◽  
Serum Ferritin ◽  
Iron Removal ◽  
Organ Injury ◽  
Cell Disease ◽  
Liver Iron ◽  
Flow Measurements ◽  
Transfusion Therapy

Abstract Between 1995 and 2004, two NIH-sponsored studies (STOP/STOP II) showed that children with sickle cell disease (SCD) and abnormal transcranial Doppler blood flow measurements (high stroke risk) are protected from stroke with regular blood transfusions. Iron overload, which may lead to complications and requires iron removal therapy, was monitored by serum ferritin (SF). Liver iron concentration (LIC) measurement was not mandated by protocol and was performed at investigator discretion. Biopsy dates and lab values were captured during STOP/STOP II, providing an opportunity to validate SF against LIC. 75 LICs on 36 patients (19 female, 17 male) at 8 centers were obtained. No liver biopsy complications were reported. LICs were correlated with STOP/STOP II core laboratory SF and alanine aminotransferase (ALT) obtained within 180 days of LICs. Median age at first biopsy was 11.1 years (range, 4.5–17.8), median time from start of transfusion was 36 months (range, 2–100). Iron removal treatment was initiated a median 23 months (range, 4–108) from start of transfusion, with deferoxamine (n=27), and/or exchange transfusion (n=9). 21 pts (58%) had multiple LIC measures: 2 (n=9), 3 (n=8), 4 (n=2), 5 (n=2). Last LICs on iron removal therapy were obtained a median 72 months (range, 35–124) from start of transfusion. Correlation between SFs and LICs were r=-0.06 (n=18) for first LICs obtained prior to iron removal therapy, r=0.50 (n=17) for last LICs obtained on iron removal therapy, and r=0.51 for all LICs (n=60). Pts with single/last LIC &gt;=15 mg/gram dry liver were significantly more likely to have ALTs &gt;=45 IU/L compared to those with LICs &lt;15 mg/gram (5/12 vs. 1/18; odds ratio 12.1; 95% CI 1.2–123.6; p=0.03). Pts with LIC &gt;=15 mg/gram and ALT &gt;=45 IU/L tended to have higher SFs then those with normal ALT (mean SF 4927 ng/ml, 95% CI 1739–8115 vs. mean SF 2255 ng/ml, 95% CI 1599–2912). 37% (7/19) of pts with LIC &gt;=15 mg/gram had SFs &lt;2000 ng/ml. 55% (11/20) of pts with repeated LICs, had last LICs &lt;15 mg/gram after initiation of iron removal therapy. SF did not correlate with LICs after initiation of blood transfusion therapy and correlated weakly after initiation of iron removal therapy. Over 1/3 of children with evidence of significant iron overload, as measured by LICs, had low serum SFs (&lt;2000 ng/ml), leading to a potentially erroneous interpretation of low iron stores. A significant portion of pts with elevated LICs had evidence of liver injury (ALT elevation). SF elevation observed in some pts may be due in part to end organ injury. Sustained iron overload control was achieved in over 1/2 of pts examined with repeated LICs.

scholarly journals Increased Liver Iron Concentration (LIC) in Adults with Non-Transfusion Dependent Sickle Cell Disease (NTD-SCD): Correlation with Serum Ferritin Concentrations

Blood ◽  
2015 ◽  
Vol 126 (23) ◽  
pp. 4594-4594
Author(s):  
Mohamed A. Yassin ◽  
Ashraf Tawfiq Soliman ◽  
Vincenzo Desanctis ◽  
Abdulqadir Nashwan ◽  
Abbas Moustafa ◽  
...  
Keyword(s):  
Iron Overload ◽  
Serum Ferritin ◽  
Research Funding ◽  
Iron Concentration ◽  
Hepatic Enzymes ◽  
Cell Disease ◽  
Liver Iron Concentration ◽  
Liver Iron ◽  
Liver Iron Content ◽  
High Liver

Abstract Introduction: Hepatic iron concentration (HIC) is used as a surrogate for total iron balance to guide chelation therapy in transfusion-dependent and independent patients. Unfortunately, liver biopsy is invasive and provides only indirect information regarding other organ systems. FerriScanprovides an accurate validated measurement of liver iron concentration (LIC) through a non-invasive, using patented R2-MRI imaging technology. Aim: To determine the iron status of 11 patients with non-transfusion dependent (NT) patients with sickle cell disease (SCD). Patients and methods: FerriScan (a quick, easy and painless, with an MRI scan time of only two minutes) is used to determine LIC in eleven adults with NT-SCD. Serum ferritin, iron concentrations and hepatic enzymes (ALT and AST) concentrations and total iron binding capacity (TIBC) were measured. Results: 11 adults with NT-SCD were studied. Three had serum ferritin > 500 umol/L , 2 out of the three (ferritin level 1138 and 531 ug/L) had high liver iron measured by ferriScan (> 30 mmol/kg dry tissue). One patient had high liver iron content despite a concomitant serum ferritin concentration = 237 ug/L. On the other hand a patient had serum ferritin = 1117 ug/L while his liver iron was still (27 mmol/kg dry tissue) in the normal range. Serum ferritin concentrations were correlated significantly with liver iron content measured by ferriScan (r = 0.47, p = 0.05). (fig) Three patients had elevated liver enzymes (ALT and AST). Neither serum ferritin, nor LIC was correlated significantly with hepatic function. Discussion: In this study significant number of patients with ND-SCD had high LIC and high serum ferritin and hepatic enzymes (ALT and AST). Elevated levels of LIC and ferritin impose high risk for hepatic disease and cardiac toxicity in these patients. Evidence suggests that patients with high LIC have higher risk of liver fibrosis and cirrhosis as a result of iron overload. In addition, Liver iron concentration (LIC) over 15.0 mg Fe/g dry weight is associated with increased risk of cardiac diseases. Moreover, the liver is considered the early warning system against later endocrine complications, due to iron overload. For NT-SCD, with increased LIC, effective management of liver iron concentration is critical to ensure risk of morbidity due to iron overload is minimized Summary: This is the first study that document increased iron overload in NT-SCD patients. Therefore, we recommend measuring serum ferritin and LIC in NT-SCD patients. Those with increased LIC and/or ferritin should be chelated to prevent long term complications of iron overload.Table.Ageserum FeTIBCFerritinliver ironALTASTyrumol/Lumol/Lug/Lmmol/kgU/LU/L32.323.755.7361.731.024.236.114.217.78.4405.717.716.422.3 Disclosures Nashwan: HMC MRC: Research Funding. Moustafa:HMC MRC: Research Funding. Elomry:HMC MRC: Research Funding.

Pancreatic Iron Deposition Following the Role of Iron Loading Among Transfusion Dependent Sickle Cell Disease Egyptian Children and Young Adults

Blood ◽  
2019 ◽  
Vol 134 (Supplement_1) ◽  
pp. 4828-4828
Author(s):  
Mohsen Saleh Elalfy ◽  
Khalid Allam ◽  
Ahmed Ibrahim ◽  
Basant Mosaad ◽  
Fatma Soliman Elsayed Ebeid
Keyword(s):  
Young Adults ◽  
Sickle Cell Disease ◽  
Iron Overload ◽  
Sickle Cell ◽  
Serum Ferritin ◽  
Iron Loading ◽  
Cell Disease ◽  
Liver Iron ◽  
Cardiac Iron ◽  
Iron Load

Background: Transfusion in sickle cell disease (SCD) is uncommon but a well-defined practice; either as a replacement in severe anemia or as a prophylactic therapy for its major complications mainly stroke. Differential iron loading in SCD especially the extrahepatic organs is not fully studied. Primary objective is to measure pancreatic iron load among Egyptian transfusion-dependant SCD patients by using MRI T2* relaxometry method. Secondaryobjective is to correlate pancreatic iron load to transfusion iron input, both hepatic and cardiac iron load, trend of serum ferritin. Subjects and Methods: Sixty-six transfusion-dependant SCD child and young adults 8-25 years with more than twenty transfusions before enrollment, non was on regular exchange transfusion; they underwent clinical and laboratory assessments; complete hemogram, serum ferritin and serum amylase. All patients performed MRI examination on a 1.5- Tesla super conductive MR Philips scanner in MRI unit in Ain Shams University Hospital; the study takes about 10 -15 minutes. Radiological quantification of iron overload was performed via simple mathematical models using Microsoft Excel Spread Sheet for heart, pancreas, and kidneys. Results: The mean age of the studied SCD patients were 15.68 ± 7.02 years, they were 35 male (53.0%), 43 of them (65.2%) had positive family history of SCD. All were multiple transfusion; 22 for cardiopulmonary complication and acute chest syndrome (ASC), nine for stroke prevention and 35 for frequent sickling crisis and symptomatic anemia. Most of patients (80.3%) were on chelation therapies that were mainly (92.5%) oral mono-therapy. High frequencies of comorbidities were recorded in the studied cohort; delayed puberty (65.2%), hepatitis C infection (23.1%) and stroke (14.1%). The studied SCD patients had median transfusion index of 120ml/kg/year with mean iron overload per day 0.23 ± 0.15 mg/kg and half of them had serum ferritin > 2500ug/L. Almost two-thirds had moderate to severe liver iron overload with median LIC 11.63 mg/g liver dry weight, none had cardiac iron overload with median cardiac T2* 31 msec and nearly half of them (42.2%) showed marked decrease in signal intensity of renal cortex with relative sparing of the renal medulla and pelvis. Most of them (86%) had normal to mild pancreatic iron overload with median pancreatic R2* 53.8 msec. Pancreatic R2 level was not significantly correlated to either transfused iron, liver iron or serum ferritin and amylase. Patients with moderate to severe pancreatic iron overload had lower pre-transfusion hemoglobin level (p=0.004), higher level of marker of hemolysis (total bilirubin (p=0.012) and indirect bilirubin (p=0.048) than those with normal pancreatic MRI. Radiological quantification of iron overload was performed via a simple cheap and quick method for analysis of data. Conclusion: Moderately heavy transfused patients with SCD had no iron overload in the heart; pancreas follow same pattern as heart with minimal or no pancreatic iron loading, however moderate to severe hepatic iron loading. Whether iron loading might be related only to frequency of transfusion or also to frequency of vaso-occlusive will be discussed. Disclosures No relevant conflicts of interest to declare.

Long-term Erythrocytapheresis Is Associated With Reduced Liver Iron Concentration in Sickle Cell Disease

2016 ◽  
Vol 38 (1) ◽  
pp. 22-26 ◽  
Author(s):  
Scott N. Myers ◽  
Ryan Eid ◽  
John Myers ◽  
Salvatore Bertolone ◽  
Arun Panigrahi ◽  
...  
Keyword(s):  
Sickle Cell Disease ◽  
Sickle Cell ◽  
Iron Concentration ◽  
Cell Disease ◽  
Liver Iron Concentration ◽  
Liver Iron

scholarly journals Correlation of Serum Ferritin Levels with Liver Iron Concentration By MRI Measurement in Sickle Cell Patients with Transfusional Iron Overload

Blood ◽  
2018 ◽  
Vol 132 (Supplement 1) ◽  
pp. 4926-4926 ◽  
Author(s):  
Germame Ajebo ◽  
Abhishek A. Mangaonkar ◽  
Imran Ahmad ◽  
Nadine Barrett ◽  
Leigh Wells ◽  
...  
Keyword(s):  
Liver Function ◽  
Iron Overload ◽  
Sickle Cell ◽  
Serum Ferritin ◽  
Iron Concentration ◽  
Liver Function Tests ◽  
Liver Iron Concentration ◽  
Liver Mri ◽  
Liver Iron ◽  
Positive Correlation

Abstract Background: Recent reports from the thalassemia literature suggest that serum ferritin may be a poor and possibly misleading measure of total iron store in heavily iron overloaded patients. Moreover, the relationship between plasma ferritin and body iron stores is distorted by ascorbate deficiency, fever, infection, inflammation, and hepatic dysfunction, all of which occur in patients with sickle cell disease (SCD). On the other hand, following the results of multiple studies that demonstrated a high correlation of hepatic iron overload determination by magnetic resonance imaging to the values found in specimens from liver biopsy, R2* liver MRI has emerged as the best noninvasive yet highly sensitive and specific method for measuring the level of iron in the liver. The goal of this study was to determine the correlation of liver iron by liver R2* MRI with serum ferritin and by extrapolation assess whether serum ferritin remains to be a useful clinical marker of iron overload in patients with SCD. We also sought to determine the correlation of liver iron concentration with abnormalities in the liver function tests. Methods: We conducted a retrospective analysis of 31 patients with sickle cell disease and transfusional iron overload who are being followed at the Augusta University Comprehensive Sickle Cell Center. Serum ferritin, hepatic R2* MRI liver iron concentration, hepcidin level, and liver function tests (AST, ALT and total bilirubin) were assessed for correlation. We used the Pearson correlation coefficient to determine the relationship between the various variables with hepatic R2* MRI. Results: Serum ferritin levels showed a statistically significant positive correlation with R2* hepatic MRI (r = 0.479 with p = 0.0085) in the patients with SCD and transfusional iron overload . We also saw a positive correlation, although not statistically significant, between hepcidin level and liver iron concentration by liver MRI(r=0.493 with P= 0.399). This may be due to the small sample size of the patients who had hepcidin levels available. On the other hand, no correlation was detected between abnormalities in liver function tests and liver iron concentration. The correlation between liver iron concentration(LIC) and AST was 0.045 with p = 0.816 and the correlation between LIC and ALT was 0.233 with p = 0.224. Conclusion: While R2* MRI is the the most accurate method to diagnose and monitor response to therapy in SCD patients with transfusional iron overload, we have found a statistically significant positive correlation with serum ferritin values. Thus, where R2* liver MRI is unavailable, serum ferritin remains a clinically useful tool that can be used in the diagnosis and monitoring of iron overload in sickle cell patients, despite its limitations. As previously reported, we did not find any correlation between LIC and liver function abnormalities in this population (Harmatz et al, 2000) These findings suggest that patients with SCD may have a different response to iron overload in comparison to patients with thalassemia or hereditary hemochromatosis. Disclosures Kutlar: Bluebird Bio: Other: DSMB Member; Sancilio: Other: DSMB Chair; Novartis: Consultancy, Honoraria, Other: Personal fees, Research Funding.

Comparison of Liver Iron Concentration Measured by the SQUID Biosusceptometers at Hamburg, Torino and Oakland in Patients with Thalassemia and Sickle Cell Disease.

Blood ◽  
2005 ◽  
Vol 106 (11) ◽  
pp. 3721-3721
Author(s):  
Ellen B. Fung ◽  
Filomena Longo ◽  
Roland Fischer ◽  
Rainer Engelhardt ◽  
Zahra Pakbaz ◽  
...  
Keyword(s):  
Sickle Cell Disease ◽  
Sickle Cell ◽  
Iron Concentration ◽  
Normal Subjects ◽  
Iron Chelator ◽  
Cell Disease ◽  
Liver Iron Concentration ◽  
Liver Iron ◽  
Round Robin Test ◽  
Highly Correlated

Abstract Assessing iron chelator efficacy in clinical trials requires standardization of liver iron concentration measurements. In a blinded round-robin test, liver iron concentration (LIC) was measured within 1 month in 18 patients with thalassemia or sickle cell disease and in 10 normal subjects at the 3 SQUID biosusceptometer systems located in Hamburg (UKE), Torino (TOR), and Oakland (CHO). Mean LIC values (range: normal up to 8000 μg/g-liver) were determined from 5 separate vertical scans. The observed intrasite precision (SD of Altman-Bland differences from duplicate measurements with repositioning) was found in the expected range of ±130 (UKE), ±200 (TOR), and 220 μg/g-liver (with 3 operators involved at CHO). Prediction of LIC at TOR and CHO in comparison with UKE was very good, with coefficients of determination between sites of R2 = 0.97, resulting in intersite standard deviations (SD) of 247 and 326 μg/g-liver, respectively. Differences of 24, 20, and 5% were noted for the comparisons UKE-TOR, CHO-TOR, and UKE-CHO, respectively (see Fig. 1). This suggests the need for further standardization of analysis methods. In conclusion, we found that intra-site precision was within an acceptable range for repeat measurements in the majority of iron overloaded subjects. Prediction of liver iron concentration at the three centers was highly correlated. Figure 1. Agreement (Passing-Bablok regression) between liver iron measurements (mean LIC from 2 positions) by the SQUID biosusceptometer system in Hamburg (LIC-UKE) and the systems in Torino (LIC-TOR) and Oakland (LIC-CHO). Figure 1. Agreement (Passing-Bablok regression) between liver iron measurements (mean LIC from 2 positions) by the SQUID biosusceptometer system in Hamburg (LIC-UKE) and the systems in Torino (LIC-TOR) and Oakland (LIC-CHO).

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