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Query: UNIPROT:P02794 (ferritin)
 17,525 document(s) hit in 31,850,051 MEDLINE articles (0.00 seconds)

The effect of riboflavin supplementation (5mg twice daily for 8 weeks) on reduced blood glutathione (GSH) and iron status was assessed in 18 patients with sickle cell disease (SCD-HbSS). Twelve SCD patients and 13 normal (Hb-AA) subjects served as the control. The total iron binding capacity (TIBC) and serum ferritin (SF) were significantly higher (p < 0.01), but GSH level, haemoglobin and transferrin saturation (TS) were significantly lower (p < 0.001) in SCD patients than in normal subjects. The administration of riboflavin elicited a significant increase (p < 0.01) in serum iron and TS but a non significant increase in SF and circulating Hb. The GSH level varied little in riboflavin supplemented but decreased significantly in unsupplemented SCD. The disparity in GSH concentration might reflect availability of FAD for regeneration of GSH from glutathione. Likewise, the haematological improvement in the supplemented group supports the assertion that riboflavin enhances erythropoiesis. For an effective management of SCD in Africa, a closer attention should be directed to the riboflavin status in haemolytic disorders.
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PMID:Clinical trial of riboflavin in sickle cell disease. 829

Transfusion-induced hemosiderosis is a serious and potentially life-threatening complication for some patients with sickle cell anemia. The use of high-dose intravenous deferoxamine (DFO) has become widespread in spite of a paucity of published data on safety and efficacy. We report a randomized double-blind study of the dose-response relationship of intravenous DFO in six subjects with sickle cell anemia and severe transfusion-induced hemosiderosis (serum ferritin 4100 to 14,176 ng/ml). Each subject received three different doses of intravenous DFO for 3 days each while consuming a constant diet. Total iron excretion (urine and fecal) was 91% greater at 180 mg/kg/day DFO than at 60 mg/kg/day DFO, and fecal iron excretion became a relatively larger proportion of total excretion at higher doses. Subsequent treatment for 3 months with 150 mg/kg/day DFO caused a 33% to 60% reduction in serum ferritin and demonstrable improvement in hepatic function in all patients. No toxicity was encountered, but DFO at 180 mg/kg/day was associated with a significant increase in fecal zinc excretion when compared with that observed at lower doses.
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PMID:Iron chelation by deferoxamine in sickle cell patients with severe transfusion-induced hemosiderosis: a randomized, double-blind study of the dose-response relationship. 832 Apr 90

To examine the relationship between hepatic iron stores and plasma ferritin concentration in individuals treated with red cell transfusion and iron chelation therapy, 37 patients with sickle cell anemia and 74 patients with thalassemia major were studied. In each patient, hepatic iron stores were measured by an independently validated noninvasive magnetic method, and plasma ferritin was determined by immunoassay. The correlation between hepatic iron and plasma ferritin was significant both in patients with sickle cell anemia (R = 0.75, P < 0.0001) and in those with thalassemia major (R = 0.76, P < 0.0001). Regression analysis showed no significant difference between the two groups in the linear relationships between hepatic iron stores and plasma ferritin. Considering all 111 transfused patients as a group, the coefficient of correlation between hepatic iron stores and plasma ferritin was highly significant (R = 0.76, P < 0.0001). Regression analysis found that variation in body iron stores, as assessed by magnetic determinations of hepatic iron, accounted for only approximately 57% of the variation in plasma ferritin, suggesting that the remainder was the result of other factors, such as hemolysis, ineffective erythropoiesis, ascorbate deficiency, inflammation, and liver disease. The 95% prediction intervals for hepatic iron concentration, given the plasma ferritin, were so broad as to make a single determination of plasma ferritin an unreliable predictor of body iron stores. Variability resulting from factors other than iron status limits the clinical usefulness of the plasma ferritin concentration as a predictor of body iron stores.
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PMID:Hepatic iron stores and plasma ferritin concentration in patients with sickle cell anemia and thalassemia major. 841 2

Studies on baboons and preliminary observations in three patients with sickle cell anemia (SS) suggested that high doses of pulse administered recombinant human erythropoietin (rHuEPO) stimulate F-reticulocyte production. We now report on the administration of rHuEPO in a double-blind format to ascertain frequency of response and potential precipitation of side effects. Ten patients were enrolled, but one was discontinued due to the indication of a blood transfusion. Of the other nine, five received rHuEPO in escalating doses (from 400 to 1,500 U per kg twice daily [BID] per week), alternating with a placebo, in blinded fashion. The second group, consisting of four patients, followed an identical protocol (except starting dose was 1,000 U/Kg, BID per week) and were iron supplemented during treatment. The criterion of response was a transient doubling (as a minimum) of the steady-state F-reticulocyte level. We found that none of the five patients in the first group responded to rHuEPO, and two of them became iron deficient, as judged by a significant decrease in ferritin. Of the second group, four patients responded with F-reticulocyte increases. In three patients, open label administration of rHuEPO confirmed the effect. We observed seven painful episodes during this study, two during the EPO administration and five during the placebo arm. Three patients were phlebotomized because the hemoglobin level increased 1.5 g/dL more than steady-state levels. Of the six patients followed-up by percent dense cell determinations, one exhibited increased levels during periods of the treatment, whereas the other five showed no change. No anti-rHuEPO antibodies were detected. We conclude that rHuEPO can stimulate F-reticulocyte response in some patients with sickle cell anemia, without apparent negative clinical side effects. The state of iron stores may be critical. Whether higher doses of rHuEPO and/or a different regimen might induce sustained F cells and fetal hemoglobin increases remains to be determined.
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PMID:F reticulocyte response in sickle cell anemia treated with recombinant human erythropoietin: a double-blind study. 841 6

Nineteen children and adolescents receiving repeated transfusions and subcutaneous desferrioxamine treatment were investigated in an attempt to quantitate iron overload non-invasively. Before patients were started on desferrioxamine individual relationships were correlated for 12 to 36 months between transfused iron, absorbed iron estimated gastrointestinally, and increasing serum ferritin concentrations. Patients with inflammation, increased liver enzymes, or haemolysis were excluded from analysis. The relationship between the variables could be described by a logarithmic regression curve (y = transfused iron [plus eventually gastrointestinally absorbed iron] = iron overload = a+b log [x = serum ferritin]) for each individual patient. All patients showed close correlation (R2) between x and y (median R2 of 0.909, 0.98, and 0.92 in thalassaemia, aplastic anaemia, and sickle cell anaemia patients, respectively). When started on desferrioxamine, current serum ferritin concentrations were used to derive the iron overload from each individual regression curve. The derived estimated iron overload ranged from 0.6 g to 31 g. Left ventricular dilatation was observed in three patients with beta thalassaemia and in one patient with aplastic anaemia with median iron overload of 20.7 (14.1-31.3) g and 24.0 g respectively. Hypothyroidism was found in four patients with beta thalassaemia and one patient with aplastic anaemia with iron overload between 14.7 (6.8 and 26.1) g and 15.1 g respectively. Human growth hormone deficiency was detected in three patients with beta thalassaemia with an iron overload of 4.2 (3.5-6.8) g; all three patients had excellent desferrioxamine compliance.
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PMID:Logarithmic quantitation model using serum ferritin to estimate iron overload in secondary haemochromatosis. 866 33

Fifteen iron-overloaded thalassaemia major (TM) patients and two homozygous sickle cell patients (SCD) were treated continuously for 7d each week with the novel 48 h continuous subcutaneous (s.c.) desferrioxamine (DFX) delivery device (code C1083, Baxter) and 10 TM patients received the 24 h continuous intravenous (i.v.) DFX delivery device (code C1071). The 27 patients had previously received conventional s.c. DFX for 8-10h on 5 or more days each week. The serum non-transferrin bound iron (NTBI) levels fell significantly in both groups within 12h of commencing the continuous infusion. In the s.c. group the mean level fell from 4.2 to 2.0 mumol/l (P = 0.001), whereas in the i.v. group the mean level fell from 3.6 to 0.1 mumol/l (P = 0.006) the initial levels being measured 12h after stopping conventional s.c. DFX. After 4 weeks there was a significant fall in serum ferritin in both groups (P = 0.009). The new DFX delivery device is effective at removing toxicfree iron from plasma and reducing body iron. Moreover, it is preferred by patients with much improved compliance compared to the conventional s.c. DFX pump.
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PMID:A novel delivery system for continuous desferrioxamine infusion in transfusional iron overload. 870 13

In this study we evaluated the nutritional status of 34 children with sickle cell disease (SS). Results were compared to 9 siblings with sickle cell trait (AS) and 35 eutrophic children who presented normal hemoglobin and normal hemoglobin electrophoresis (AA). All of then came from low socioeconomic level. Analysis of the growth velocity curves revealed in SS group, tendency to increase deficit in weight and height with age. There was no relation between weight/height (W/H) and height/age (H/A) percentile and hemoglobin levels. There was no significant relation between nutritional status and severity of the disease. SS group showed significant skeletal maturation delay, the same did not occur with the siblings (AS group). Plasma zinc levels were significantly lower in SS group than in AS and AA groups. In SS group there was some association between lower plasma zinc levels and H/A percentile lower or equal to 10. Plasma copper levels were significantly greater in SS group than in AS and AA ones, and there was no relation between plasma copper levels and serum ferritin levels. In conclusion, our patients with sickle cell disease showed indexes of malnutrition, iron deficiency, hypercupremia and low plasma zinc levels related to low stature.
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PMID:Zinc, copper and iron and their interrelations in the growth of sickle cell patients. 933 3

Cerebrovascular accidents (CVA) as a complication of sickle cell disease occur most frequently in childhood. Life-long transfusion prevents recurrent stroke, but inevitably leads to iron overload. Although effective chelation exists, many patients are not compliant. Erythrocytapheresis, an automated method of red blood cell exchange, was evaluated as an alternative to control transfusion-related iron load. Eleven patients with sickle cell anemia and a history of stroke were converted from simple transfusion to pheresis. Total time on pheresis for the group averaged 19 months (range 4-36 months). No significant complications occurred with a mean pre-pheresis hemoglobin S (Hb S) level of 44%. Blood utilization increased by an average of 50%. The effect of pheresis on serum ferritin depended on the patient's pre-pheresis ferritin level and chelation regimen. Ferritin levels remained stable for chelated patients with ferritin levels > or = 5,000 ng/ml, but decreased in a chelated patient with a pre-pheresis ferritin level of 4,000 ng/ml. For non-chelated patients with significant pre-pheresis iron load, ferritin levels remained stable. No patient on chelation prior to pheresis was able to discontinue deferoxamine. However, one patient with pre-pheresis ferritin of 500 ng/ml maintained serum ferritin levels < 200 ng/ml for 36 months of pheresis without chelation. Pheresis is more expensive than simple transfusion unless the cost of chelation and organ damage from iron overload are considered. Erythrocytapheresis is a safe method of controlling Hb S levels and limiting or preventing iron load in chronically transfused sickle cell patients.
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PMID:Erythrocytapheresis limits iron accumulation in chronically transfused sickle cell patients. 972 73

Renal involvement is common in homozygous sickle cell disease (HbSS), including glomerular hypertension and hypertrophy similar to that seen in rodent models of ablative nephrectomy and stage I diabetic nephropathy (DN). The proteinuria in the rodent models is attenuated by angiotensin converting enzyme inhibition (ACEI). Microalbuminuria (MA) is a sensitive marker for renal involvement in DN prior to the development of proteinuria, and is also attenuated with ACEI. Elevated urinary microalbumin/creatinine ratios (U Alb/Cr) >20 mg/g Cr are reported in 39%-43% of adults with HbSS, and studies are ongoing in this age group to assess the effect of attenuated proteinuria by ACEI on long-term renal function. The purpose of this study was to prospectively investigate the prevalence of MA in children with HbSS and determine factors which affect its expression. U Alb/Cr values were measured on spot urine samples in 102 children (aged 2-18 years, mean 9.47+/-4.62, M:F=53:49) by rate nephelometry. Children with prior known proteinuria, hypertension, or fever/pain episode in the last 15 days were excluded. MA was present in 26.5% of all children with HbSS. However, in children between the ages of 10 and 18 years, the prevalence was 46% (similar to the prevalence in adults). There was a strong correlation between patient age and prevalence of MA (P<0.0001) by both univariate and multivariate analysis. However, pain frequency, hospitalization, transfusion program, ferritin levels, and Cr clearance (C(Cr)) did not correlate with prevalence, although C(Cr) (as estimated by Schwartz formula) was elevated in all. We conclude that the prevalence of MA in the 2nd decade of life is similar to that in adults.
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PMID:Prevalence of microalbuminuria in children with sickle cell disease. 974 72

Despite regular blood transfusion and desferrioxamine treatment, growth impairment and pubertal delay are commonly seen in children and adolescents with transfusion-dependent thalassaemia and sickle cell disease (SCD). We evaluated growth parameters and sexual maturation in a large cohort of children and adolescents with SCD (n = 110) and thalassaemia (n = 72) receiving nearly the same protocol of transfusion and chelation, and compared them with those for 200 normal age-matched children, 30 children with constitutional delay of growth (CSS), and 25 children with growth hormone deficiency (GHD). Before transfusion, haemoglobin concentration had not been less than 9 g/dl in the past 7 years; desferrioxamine was administered for 7-10 years, including by the intramuscular and subcutaneous routes, three times or more per week. The height standard deviation score (HtSDS), growth velocity (GV) (cm/yr), and growth velocity standard deviation score (GVDSD) of children and adolescents with thalassaemia and SCD were significantly decreased compared to normal children (p < 0.01). Forty-nine per cent of thalassaemic patients and 27 per cent of patients with SCD had HtSDS less than -2, and 83 per cent of thalassaemic patients and 67 per cent of SCD patients had HtSDS less than -1. Fifty-six per cent of thalassaemic children and 51 per cent of children with SCD had GVSDS less than -1. The GV of thalassaemic children was significantly slower than that for children with SCD. Children with thalassaemia and SCD had HtSDS and GVSDS comparable to those for children with CSS but higher than those for patients with GHD. Serum ferritin concentration was correlated significantly with the linear GV in all patients (r = 0.45, p < 0.001). The bone age delay did not differ among the three groups with thalassaemia, SCD and CSS, but the delay was significant in the group with GHD. The mid-arm circumference was significantly smaller in children with thalassaemia and SCD than in normal children. The triceps skin-fold thickness of patients with SCD was significantly decreased compared to thalassaemic and normal children. The upper/lower segment ratio was significantly lower in thalassaemic and SCD patients than in normal children. In thalassaemic patients between the ages of 13 and 21 years a complete lack of pubescent changes was present in 73 per cent of boys and 42 per cent of girls. Seventy-four per cent of the thalassaemic girls had primary amenorrhoea. Girls with SCD aged between 13 and 21 years had markedly delayed breast development and menarche. Twenty-five per cent of boys with SCD above the age of 14 years had absence of testicular development. Males with thalassaemia and SCD who had spontaneous testicular development had significantly smaller testicular volume than did normal controls. Short children with thalassaemia and SCD had significantly decreased serum insulin-like growth factor 1 (IGF-1) concentrations compared to children with CSS. Collectively, these data confirm the high prevalence of impaired growth and pubertal delay/failure in children and adolescents with thalassaemia and SCD. The aetiology of impaired growth includes the contributions of lack of pubertal growth spurt due to delayed/absent puberty, decreased synthesis of IGF-1 which might be secondary to a disturbed GH-IGF-1 axis and/or under nutrition, probably due to the hypermetabolic status of these children. It is suggested that newer protocols of treatment, in addition to optimization of transfusion and chelation requirements, should increase the caloric intake of these patients and properly manage their pubertal delay-failure in order to improve their adult height.
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PMID:Growth and pubertal development in transfusion-dependent children and adolescents with thalassaemia major and sickle cell disease: a comparative study. 1019 89


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