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Objective: The aim of this study was to determine the response to recombinant human erythropoietin (rhEPO) in anemic pregnant women with heterozygous hemoglobinopathies., Methods: A prospective study including 19 consecutive pregnant women with anemia and heterozygous hemoglobinopathy was performed. Treatment was divided into two phases: the initial low-dose phase and the subsequent high-rhEPO phase. In the initial phase, 3 x 10,000 U of rhEPO was administered with intravenous iron sucrose. In patients showing a poor response (Hb increase <1 g/dl) to low-dose rhEPO, the rhEPO dose was increased to 20,000 U per treatment in the subsequent phase., Results: All patients showed stimulation of erythropoiesis as evidenced by an increase in hemoglobin. In 13 patients, a good response to therapy was observed (mean Hb increase 1.6 +/- 0.5 g/dl). In 6 patients, resistance to rhEPO was noted (mean Hb increase 0.5 +/- 0.5 g/dl). The mean gestational age at the start of therapy was 28 weeks of gestation and at the end 32 weeks. The mean duration of a complete therapy was 3.5 weeks (range 2-4.5 weeks). If calculated for body weight, the initial low- rhEPO dose of 160.4 +/- 30.6 U/kg body weight/treatment was increased to 320.9 +/- 61.2 U/kg body weight/treatment in the subsequent phase., Conclusion: Response to rhEPO treatment differs widely in anemic pregnant patients with heterozygous hemoglobinopathy. Resistance was observed in anemic pregnant patients with the beta-thalassemia trait originally from the Mediterranean region., (Copyright 2006 S. Karger AG, Basel.)

Objective: The hydroxamic acid derivatives of short-chain fatty acids, butyryl and propionyl hydroxamate, subericbishydoxamic acid, and suberoylanilide hydroxamic acid, are potent inhibitors of histone deacetylase (HDAC) and have been shown to induce fetal hemoglobin in vitro. In this study we examined whether these compounds have erythropoietic activity and can induce gamma globin gene expression in vivo., Materials and Methods: Transgenic mice heterozygous for a deletion beta thalassemia and hemizygous for a human gamma globin transgene were treated with these compounds and hematologic responses as well as the induction of gamma gene expression were evaluated. Hematologic studies included measurement of reticulocytes, hematocrit, and the in vivo levels of BFU-E. Effects on globin gene expression were assessed by measuring F reticulocytes and the human gamma/murine alpha globin mRNA ratios by RNAse protection assay., Results: Propionyl and butyryl hydroxamate increased reticulocytes by 71% and 139%, the in vivo BFU-E counts by 75% and 51%, and the in vivo gamma gene expression by 33.9% and 71% respectively. SBHA and SAHA had no erythropoietic activity in vivo., Conclusion: Hydroxamic acid derivatives can stimulate the in vivo erythropoiesis and fetal globin production in a thalassemic murine model. The combined effect of certain histone deacetylase inhibitors on erythropoiesis and on gamma gene expression make these compounds desirable targets for development of therapeutics for beta chain hemoglobinopathies.

New drugs, recently available for treatment of different forms of anaemia, have somehow changed the therapeutic scenario in paediatric haematology. The aim of this review is to focus on the newest molecules discussing indications, clinical usefulness and related problems. Erythropoietin, the specific growth factor of red cell precursors, is now an established option for anaemia of chronic renal failure, prematurity, bone marrow transplantation and chemotherapy. Anti-CD20 monoclonal antibody, a novel cytotoxic molecule for mature B lymphocytes, has proven to be effective in the treatment of refractory autoimmune cytopenias. Haemoglobin analogues are currently under investigation, in order to obtain a synthetic oxygen-carrier that can substitute blood transfusions. Finally drugs that are able to increase the production of haemoglobin F have been used in thalassemias and haemoglobinopathies. For patients with sickle cell disease, hydroxyurea is no longer an experimental tool; it has given rise to several trials, where it has proven to be effective in terms of both clinical and haematological improvement.

By including hemoglobinopathies in the National Neonatal Screening Program (PNTN), Brazilian Ministry of Health Directive # 822/01 has taken an important step towards recognition of their relevance for public health in the country. However, except at a few specialized centers, the public health care system is unprepared to meet the goals laid out under the directive. As the first step to effectively implement the guidelines, it is thus necessary to disseminate information on hemoglobinopathies among health professionals working in public health, especially those involved in neonatal screening. This article discusses some of the unique characteristics of hemoglobinopathies in comparison to other metabolic disorders included in the National Neonatal Screening Program. The authors also analyze potential sources of misunderstanding that could jeopardize the program's outcome.

Patients with sickle cell disease often seek treatment for rapid periorbital swelling due to infarction of the orbital bones. Because of resulting orbital compression syndrome, treatment with corticosteroids and antibiotics is advisable. If spinal tuberculosis occurs in patients with sickle cell anemia, radiologic signs will be a combination of the two conditions. The diagnosis of juvenile rheumatoid arthritis is usually delayed in patients with sickle cell disease. Sulphasalazine is the disease-modifying drug of choice for treating juvenile rheumatoid arthritis, because it also reduces the adhesiveness of sickled red cells. TNF-alpha inhibitors may also be useful for treating these patients. A volumetric method to determine the size and special distribution of the necrotic lesions of the femoral head has been developed using magnetic resonance imaging scans. With this method it will be easier to determine which early lesions require core decompression, or which ones should be treated conservatively. Osteomyelitis can be differentiated from bone infarction with the use of segmental radionuclide bone-marrow and bone scans. Reduction in frequency of painful crises can be achieved by increasing fetal hemoglobin with the use of hydroxyurea. The treatment of the actual pain requires decisions about the analgesics that are used as well as the route of their administration. Ketorolac monotherapy is likely to fail in the presence of an initial high pain score or with involvement of four or more pain sites.

The outlook for patients with sickle cell disease has improved steadily during the last two decades. In spite of these improvements, curative therapies are currently available only to a small minority of patients. The main theme of this chapter is to describe new therapeutic options that are at different stages of development that might result in further improvements in the outlook for patients with these disorders. Dr. Joseph DeSimone and his colleagues had previously made the important observation that the hypomethylating agent 5-azacytidine can reverse the switch from adult to fetal hemoglobin in adult baboons. Although similar activity was demonstrated in patients with sickle cell disease and beta-thalassemia, concern about the toxicity of 5-azacytidine prevented its widespread use in these disorders. In Section I, Dr. DeSimone discusses the role of DNA methylation in globin gene regulation and describe recent clinical experience with decitabine (an analogue of 5-azacytidine) in patients with sickle cell disease. These encouraging studies demonstrate significant fetal hemoglobin inducing activity of decitabine in patients who fail to respond to hydroxyurea. In Section II, Dr. George Atweh continues the same theme by describing recent progress in the study of butyrate, another inducer of fetal hemoglobin, in patients with sickle cell disease and beta-thalassemia. The main focus of his section is on the use of a combination of butyrate and hydroxyurea to achieve higher levels of fetal hemoglobin that might be necessary for complete amelioration of the clinical manifestations of these disorders. Dr. Atweh also describes novel laboratory studies that shed new light on the mechanisms of fetal hemoglobin induction by butyrate. In Section III, Dr. Ronald Nagel discusses the different available transgenic sickle mice as experimental models for human sickle cell disease. These experimental models have already had a significant impact on our understanding of the pathophysiology of sickle cell disease. Dr. Nagel describes more recent studies in which transgenic sickle mice provide the first proof of principle that globin gene transfer into hematopoietic stem cells inhibits in vivo sickling and ameliorates the severity of the disease. Although stroke in adult patients with sickle cell disease is not as common as in children, adult hematologists, like their pediatric colleagues, need to make management decisions in adult patients with a stroke or a history of stroke. Dr. Robert Adams has led several large clinical studies that investigated the role of transfusions in the prevention of stroke in children with sickle cell disease. Much less is known, however, about the prevention of first or subsequent strokes in adult patients with sickle cell disease. In Section IV, Dr. Adams provides some general guidelines for the management of adult patients with stroke while carefully distinguishing between recommendations that are evidence-based and those that are anecdotal in nature.

An attempt was made to find better symptomatic treatment for beta-thalassemia/hemoglobin E (beta-thal/Hb E) patients in order to reduce their blood demand. Oral administration of dilazep was prescribed for these patients and a clinical trial was conducted over a 2-year period as a cross over placebo control study. Seventeen beta-thal/Hb E patients were enrolled in the study. All of them received dilazep and placebo for 10 months at different periods of time and were taken care of by the same doctor throughout the study. The blood demand of the same patients during the period of receiving dilazep with the period of receiving placebo, was 1.5 +/- 1.8 U/10 months versus 2.2 +/- 2.6 U/10 months, respectively. Thus dilazep showed a benefit in decreasing the blood demand by about 50% although the results did not reach statistical significance (p = 0.1). There was a statistical difference in hemoglobin concentration of the patients receiving dilazep compared with placebo (p = 0.038). While receiving dilazep the mean +/- SD hemoglobin level was 5.82 +/- 0.8 g/dl, significantly higher than while receiving placebo (5.66 +/- 0.9 g/dl) (p = 0.038). The liver, and renal function tests, and cardiac enzyme levels of the patients showed no significant changes throughout the study. However, one case had a problem with bleeding following tooth extraction whilst receiving dilazep and needed 1 unit of blood transfusion. In conclusion, administration of dilazep to patients with beta-thal/Hb E increased the patients' hemoglobin and reduced their blood demand with few side effects.

Pharmacologic agents such as hydroxyurea (HU), N, 3-4 trihydroxybenzamide (didox), and isobutyramide (ISB) can elevate gamma-globin as a potential treatment for the beta-hemoglobinopathies. In these experiments, transgenic mice with 5'HS2 from the human beta-globin locus control region, the fetal (A gamma), and adult (beta s) globin genes were used. Mice were treated with HU, didox, or ISB individually, or with combinations of HU or didox with ISB. The aim was to determine whether these drugs have synergistic effects on the induction of fetal hemoglobin (HbF) and whether the combination regimens are more hematotoxic. In the combination regimens, injections of HU or didox for five weeks were concomitant with ISB treatment every other day for the final three weeks of treatment. The combination of HU + ISB was more hematotoxic than the individual drugs based on significantly increased percentages of reticulocytes and reduced hemoglobin, indicating that caution should be taken in treatments involving combinations of these types of drugs. The didox + ISB combination was not more hematotoxic than the individual drugs. HbF was not induced in the groups treated with the combinations of HU or didox with ISB compared to the individual agents. There was a negligible effect on the percentage of HbF and an unexpected negative effect on the percentage of F cells. The results also have implications for future testing of HbF-inducing drugs in mouse models. In control mice that were phlebotomized but not treated with any drugs, increased percentages of F cells were observed, indicating that blood sampling can cause this effect. In addition, increases in the percentage of F cells did not correlate with increases in the percentage of HbF, indicating that monitoring F cells alone is not a sufficient measure of HbF induction.

Butyric acid, a short chain fatty acid (SCFA), is a natural component of the animal metabolism. Physiological concentrations induce multiple and reversible biological effects. They concern regulatory mechanisms of gene expression conducing to promote markers of cell differentiation, apoptosis and cell growth control. The described hyperacetylation of histones and the induction of several immune or non-immune cell-activating mediators are consistent with the pleiotropic stimulatory effect of the agent. Butyric acid is considered as a biological response modifier (BRM) and is an interesting tool for biological studies. The history of butyric acid as a putative medication in human health is spanning since 60 years and is confusing in part because of conflicting data between exciting experimental results and clinical trials. In light of minimal impact of systemic therapy and the short half-life of the saline molecule used, it is evident that continuous infusions of butyrate are required to improve the efficacy of the treatment. Butyric acid has been viewed with skepticism because of less convenient for long-term chronic therapy. New experimental data from several studies conduced within the past decade with butyric derivatives, delivery systems, and long-acting prodrugs, have demonstrated the practical value of the therapeutic concept. To support issues regarding clinical development, it was of interest to evaluate the recent information, showing butyric acid currently considered as therapeutic purposes in the treatment of colorectal cancer and hemoglobinopathies.

Re-activation of the fetal globin genes is the most realistic approach to correct the deranged pathophysiology of the haemoglobinopathies because the presence of gamma-chains can neutralize the toxic effects of the unbound alpha-globin chains in the beta-thalassaemias and inhibit the polymerization of Hb S in the sickle cell syndromes. Re-induction of fetal haemoglobin synthesis can be brought about either by direct activation of the respective promoter genes and possibly other positively acting elements, or by recruitment into proliferation and differentiation of a population of erythroid precursors which retain the gamma-chain synthesis programme but remain dormant in the bone marrow of the adult unless called up in cases of acute erythroid expansion. Examples of the first group include the butyric acid and derivatives and 5' azacytidine. The second group comprises erythropoietin and a series of cytostatics, with hydroxyurea as the main representative. The activity of most of the above agents has already been studied in cell cultures and animals and confirmed in several patients, both at the haematological and biochemical level as well as through their frank clinical improvement. However, application of these drugs at large is not yet justified because a series of questions concerning their long-term efficacy, the correct dosage and timing, their tolerance and toxicity, and the potential long-term dangers, including mutagenicity are still unresolved.

Phenylbutyrate has been shown recently to induce fetal hemoglobin (HbF) production in patients with sickle cell anemia and beta thalassemia. We have now examined related aromatic fatty acids in order to define the range of active structures and identify plausible mechanisms of action. Structure-function analysis revealed that for effective stimulation of HbF in erythroid precursors: (1) the ideal length for the aliphatic side chain is four carbons; (2) oxygen or sulfur substitutions in the carboxylic chain are allowed, as evidenced by the equal or increased activity of phenoxypropionate, benzylthioglycolate, and benzyloxyacetate compared with phenylbutyrate; and (3) blocking the carboxylate group by conversion to the amide form greatly reduces potency. Molecular analysis indicated that the prototype agent, phenylbutyrate, increases HbF production through transcriptional activation of the gamma-globin gene. The latter contains a butyrate responsive promoter known to up-regulate transcription in the presence of short-chain fatty acids of three to five carbons. To determine whether stimulation of an element in this promoter by phenylbutyrate and its analogues might contribute to their mechanism of action, we used a transient expression system involving K562 erythroleukemia cells transfected with a luciferase reporter gene driven by the minimum gamma-globin promoter. Transcriptional activation in this experimental system correlated well with the capacity of an aromatic fatty acid to increase HbF production in erythroid precursors (r = 0.94). Our studies identify potent analogues of phenylbutyrate for the treatment of beta-chain hemoglobinopathies, and suggest that stimulation of a butyrate responsive promoter may be responsible for their activity.

Purpose: Ototoxicity often limits the dose of desferrioxamine (DFO) tolerated by patients who are transfusion dependent. Current recommendations advise doses of < 50 mg/kg/day after early reports noted higher rates of oxotoxicity with increasing doses. There have been no follow-up studies to determine the effect of this recommendation on oxotoxicity and iron overload., Methods: We followed 28 patients who were chronically chelated with serial audiograms over a 5-year period. Patients with and without oxotoxicity were compared with respect to age, disease, DFO dose, peak DFO dose, length of DFO therapy, ferritin, and therapeutic index., Results: Eight of the 28 patients (29%) had an abnormal audiogram during threshold testing. Two patients had two separate episodes with hearing deficit. Nine of the 10 episodes were high-frequency losses, with seven being moderate and three mild. All deficits were rapidly reversible with DFO dose reduction. No significant differences were found between the affected and unaffected groups with respect to age, DFO dose or duration, ferritin, or therapeutic index. Numbers of affected patients were small, but patients with SCD differed from patients with thalassemia in that they developed ototoxicity earlier and with lower doses of DFO and lower therapeutic indexes., Conclusions: Despite DFO doses usually felt to be low risk for ototoxicity, we found a high rate of ototoxicity in our patients who we've chronically chelated. No variables were identified that reliably predicted ototoxicity. We stress the need for regular audiological exams and feel no dose of DFO is "safe" from the development of ototoxicity.

Transfusion is associated with improvement of life expectancy in beta thalassemia and sickle cell disease (SCD). Bone marrow transplantation concerns only a few patients. Among potentially useful therapeutic agents which can induce fetal hemoglobin (HbF) production, hydroxyurea (HU) stands out in particular for SCD. In our sickle cell center, 10 patients with SCD received HU for chronic leg ulcer with good results in terms of healing (7 among 10, who required no additional transfusion). A few patients, most of them over 30 years, received HU for chronic organ failure at the onset. HU on long term therapy over one year improved general status, Hb level, in 7 patients with beta thalassemia intermedia. A major challenge in the coming years will be the effective evaluation of clinical efficiency and the comparison of risks and benefits of such compounds versus transfusion.

The inherited beta-hemoglobinopathies (sickle cell disease and beta thalassemia) are the result of a mutation in the adult (beta) globin gene. The fetal globin chain, encoded by the gamma globin genes, can substitute for the mutated or defective beta globin chain, but expression of the gamma globin gene is developmentally inactivated prior to birth. Re-inducing expression of the normal fetal globin genes is a preferred method of ameliorating sickle cell disease and the beta thalassemias. Stimulation of as little as 4-8% fetal globin synthesis in the bone marrow can produce > 20% fetal hemoglobin in the peripheral circulation, due to enhanced survival of red blood cells containing both sickle and fetal hemoglobin, compared to those containing sickle hemoglobin alone. Butyric acid and butyrate derivatives are generally safe compounds which induce fetal hemoglobin production by stimulating the promoter of the fetal globin genes. An initial trial with the parent compound, delivered as Arginine Butyrate, has demonstrated rapid stimulation of fetal globin expression to levels that have been shown to ameliorate these conditions. Phase 1 trials of an oral butyrate derivative with a long plasma half-life have just begun. These agents now provide a specific new approach for ameliorating these classic molecular disorders and merit further investigation in larger patient populations.

Between July 1973 and July 1974 all adult patients with hypochromic anemia and a mean corpuscular volume of 75 mum3 or less were screened for hemoglobinopathies. Of the 490 patients 105 had beta-thalassemia trait, 11 had alpha1-thalassemia trait, 4 had hemoglobin Lepore trait and 1 had hemoglobin H disease. Of 48 inpatients whose charts were reviewed 19 had been on oral iron therapy and 7 of them had been given iron intramuscularly. Of 27 outpatients interviewed 10 had been on intermittent iron therapy for 18 months or more; 4 had been given at least 1 g of intramuscular iron. Iron deficiency was not documented in any of these patients. Iron deficiency should be diagnosed by means other than the presence of a hypochromic picture in the peripheral blood before iron therapy is instituted, particularly in communities with a large population of Mediterranean or South-East Asian origin.