Athens University thalassemia expertise unit: evolution, structure, perspectives and patients' expectations.

Thalassemia Expertise Centres (TECs), were first organized in developed countries with high thalassemia prevalence in the 70's to meet the increasing demands of the implementation of frequent transfusions in the treatment of thalassemia, and to consequently adopt, the rapid advances in the management of the disease. Recent evaluation of longitudinal implementation of the national programs for prevention and treatment, demonstrated their efficacy for patients and public health. The beneficial effects focused on clinical symptoms amelioration, reduction of incidence and severity of complications and considerable improvement in survival, quality of life and social adaptation.National programs leaded to the modification of the most common genetic, fatal pediatric disease with short survival, to a chronic long-lived disease for adults and a very rare disease for children. In the few developed countries new perspectives for pediatric TECs need to be considered.

New insights into the exercise intolerance of beta-thalassemia major patients.

The purpose of our study was assessment of the relative contribution of the systems involved in blood gas exchange to the limited exercise capacity in patients with beta-thalassemia major (TM) using integrative cardiopulmonary exercise testing (CPET) with estimation of oxygen kinetics. The study consisted of 15 consecutive TM patients and 15 matched controls who performed spirometric evaluation, measurement of maximum inspiratory pressure (Pimax) and an incremental symptom-limited CPET on a cycle ergometer. Exercise capacity was markedly reduced in TM patients as assessed by peak oxygen uptake (pVO(2), mL/kg/min: 22.1+/-6.6 vs 33.8+/-8.3; P<0.001) and anaerobic threshold (mL/kg/min: 13.0+/-3.0 vs 18.7+/-4.6; P<0.001) compared with controls. No ventilatory limitation to exercise was noted in TM patients (VE/VCO(2) slope: 23.4+/-3.2 vs 27.8+/-2.6; P<0.001 and breathing reserve, %: 42.9+/-17.0 vs 29.5+/-12.0; P<0.005) and no difference in oxygen cost of work (peak VO(2)/WR, mL/min W: 12.2+/-1.7 vs 12.2+/-1.5; P=NS). Delayed recovery oxygen kinetics after exercise was observed in TM patients (VO(2)/t slope, mL/kg/min(2): 0.67+/-0.27 vs 0.93+/-0.23; P<0.05) that was significantly correlated with Pimax at rest (r: 0.81; P<0.001). The latter was also significantly correlated to pVO(2) (r: 0.84; P<0.001) and inversely correlated to ferritin levels (r: -0.6; P<0.02). Exercise capacity is markedly reduced in TM patients and this reduction is highly associated with the limited functional status of peripheral muscles.

Heart failure in beta thalassemia: a 5-year follow-up study.

PURPOSE: To evaluate the survival of patients with beta thalassemia and heart failure who were treated with iron chelation therapy. SUBJECTS AND METHODS: Fifty-two consecutive patients with beta thalassemia and heart failure were followed in a prospective 5-year study. All patients underwent a full clinical examination with chest radiograph, electrocardiogram, and echocardiographic investigation performed at 6-month intervals or when a new symptom developed. RESULTS: Of the 52 patients (mean [+/- SD] age, 24 +/- 5 years), 25 (48%) survived 5 years after the onset of heart failure. Forty-three patients had left-sided heart failure, and 9 had right-sided heart failure. Those with left-sided heart failure were younger at presentation with heart failure (22 +/- 4 years vs. 31 +/- 6 years; P <0.001), had lower ejection fractions (36% +/- 9% vs. 64% +/- 10%; P <0.001), and had a lower mean serum ferritin level (3355 +/- 1241 ng/mL vs. 6,397 +/- 1,613 ng/mL; P <0.001). CONCLUSION: The 5-year survival rate in patients with beta thalassemia with heart failure was greater than previously reported. There are clinical characteristics that may make patients more likely to develop left- or right-sided heart failure.

Developmental changes in hemoglobin F levels during the first two years of life in normal and heterozygous beta-thalassemia infants.

To study the developmental pattern of hemoglobin F (HbF) during the first two years of life, levels of HbF were estimated in two groups of infants: 117 normal infants and 98 heterozygotes for beta-thalassemia, all aged between 1 and 24 months. The results may be summarized as follows: (1) Levels of HbF in beta-thalassemia heterozygotes were significantly higher than those of normal infants of the same age (P less than .01). (2) A reference curve for the decline of HbF in infants with beta-thalassemia trait was established to facilitate the diagnosis of heterozygotes during this period of life. (3) Hemoglobin A2 (HbA2) was also higher in beta-thalassemia heterozygotes than in normal infants of the same age. HbA2 increases with increasing age, reaching normal adult values at age 5 to 6 months. It is postulated that the higher level of HbF in heterozygous infants during the first two years of life is associated with the presence of the beta-thalassemia gene, which influences the increased synthesis of HbF in red cell.

HBeAg-negative hepatitis B in a previously thalassemic patient during immunosuppressive therapy for chronic GVHD.

We report the case of a 15-year-old previously thalassemic girl who, 15 months after allogeneic BMT, developed HBeAg-negative hepatitis B (variant with mu-1896). In the absence of another route of transmission, HBV reactivation is postulated. The time of emergence of the HBV variant (with mu-1896) is probably related to the development of anti-HBe immunity. This mutant strain is associated with fulminant hepatitis. The patient achieved complete remission and HBV eradication despite having moderate GVHD and receiving immunosuppressive therapy.

ARDS in a patient with homozygous beta-thalassemia due to yersiniosis.

We report a case of Yersinia enterocolitica sepsis syndrome and the acute respiratory distress syndrome in a chronically transfused adolescent with beta-thalassemia. This manifestation of serious Y. enterocolitica infection has not previously been reported. Dyspnea, hypoxia, and fever were the principal features of the clinical presentation. The acute onset of respiratory symptoms occurred after appendectomy. Chest radiographs revealed frontal bilateral infiltrates and alveolar consolidation to three quadrants. Y. enterocolitica was identified from blood and intraoperative appendix cultures. Although there was no need for mechanical ventilation, a remarkable persistence of clinical and X-ray findings was noted. Therapy with high levels of oxygen, and intravenous amikacin and piperacillin/tazobactam led to a favorable outcome.

Glucose disturbances and regulation with glibenclamide in thalassemia.

Specific laboratory and clinical characteristics indicate that the pathogenesis of diabetes in patients with thalassemia resembles the pathogenesis of maturity-onset diabetes (type II). Thus oral hypoglycemic agents may be used to regulate blood glucose levels by induction of insulin secretion and reduction of insulin resistance. The efficacy of glibenclamide administration in the management of glucose disturbances was evaluated in 33 patients with thalassemia, aged 12-30 years (mean 17.4 +/- 3.7), in whom diet and exercise failed to regulate hyperglycemia. The results were compared to 30 thalassemic patients (mean age 18.4 +/- 4.8 yr), who followed only diet and exercise. Improvement of OGTT was observed in 73% of the treated patients versus 43% of the control group for a mean period of 59 months. Deterioration of OGTT occurred more rapidly (33.7 +/- 26.1 vs 40.7 +/- 34.5 mos), and in more patients of the untreated group (57%) than in treated patients (27%). Among treated patients, effectiveness of oral hypoglycemic agents lasted longer in patients with diabetic (64.1 +/- 40.3 mos) than in patients with impaired curves (54.2 +/- 31 mos).

Growth and management of short stature in thalassaemia major.

UNLABELLED: With modern treatment and longer survival of patients with homozygous beta-thalassaemia endocrine dysfunction assumes greater importance. Short stature, delayed puberty and hypogonadism are major problems in both adolescent and adult patients. Growth failure has been attributed to GH deficiency (hypothalamic or pituitary), hypothyroidism, delayed sexual maturation, hypogonadism, diabetes mellitus, zinc deficit, low Hb levels, bone disorders and desferrioxamine toxicity. The present report concentrates on the incidence of short stature among children aged 7-8 years (n = 50) and young adults aged 20-29 years (n = 93) with blood transfusion dependent homozygous beta-thalassaemia appropriately treated who have entered and completed puberty spontaneously (n = 45) or with treatment (n = 48) and have attained final height. It also concentrates on the role of GH in the growth retardation of 65 blood transfusion dependent thalassaemia major patients, their GH response to provocative stimulation, the effect of rhGH therapy on growth and final height in 13 patients who had GH deficiency and the effect of long acting androgens on growth and final height of 11 short boys with thalassaemia major, delayed puberty and normal GH secretion. CONCLUSION: 8% of young boys with thalassaemia major aged 7-8 years have short stature. 12% of the older boys and 15% of the older girls without endocrinopathies had height < 3rd percentile. This incidence was 29% when endocrinopathies were present. GH deficiency is rare among short blood transfusion dependent thalassaemia major patients (20%) and seems to play a limited role in the etiology of growth retardation. One year treatment with rhGH improved growth rate and predicted height without causing serious metabolic problems. Long term administration of rhGH is also safe and promising. Patients with thalassaemia major can achieve acceptable final heights but below their target heights with rhGH therapy. Low dose long acting sex steroid treatment in boys with delayed puberty, delayed bone age and without GH deficiency for a year or more is safe and can produce similar results to those obtained with rhGH therapy.

[Clinical evaluation of various preventive methods for non-hemolytic transfusion reactions]. / Evaluation clinique de différentes méthodes préventives des réactions transfusionnelles non hémolytiques.

A study has been carried out on the incidence of non-hemolytic transfusion reaction on a group of patients suffering from thalassemia. Of this group, the rate of reactions per patient, based on the relationship between the number of patients with non-hemolytic transfusion reactions and the total number had risen to 31.8%. 83.7% of the patients with non-hemolytic transfusion reactions did not give a positive reaction to lymphocytotoxicity. 654 patients having, or not having shown a non-hemolytic transfusion reaction received washed red cell concentrates prepared extemporaneously. This process allowed the rate of reaction per patient to drop to 3.9%. The transfusion of deleucocytated red cell concentrates by filtration, carried out on a group of 188 patients, made the rate of reaction per patient drop to 2.8%. As regards to rate reaction per patient, there is no significant difference statistically between these two groups, however, it must be pointed out that the administration of filtered red cell concentrates, by deleucocytation, notably improves the incidence of a feverish reaction, while the administration of washed red cell concentrates has an important impact on allergic reactions. Interestingly, in solution, the washed red cell concentrates have the added advantage of having only very small quantities of free iron or vasoactive proteic derivatives. The new four bag system, now allows us to collect, separate and wash in a closed circuit. Compared to the traditional method this system has the advantage of assuring greater efficiency and security. In conclusion, for the first time, the administration of washed red cell concentrates on patients who receive regular transfusions, may represent a good procedure, combined or not with deleucocytation by filtration, as to prevent the occurrence of non-hemolytic reactions.

Impaired oxygen kinetics in beta-thalassaemia major patients.

AIM: Beta-thalassaemia major (TM) affects oxygen flow and utilization and reduces patients' exercise capacity. The aim of this study was to assess phase I and phase II oxygen kinetics during submaximal exercise test in thalassaemics and make possible considerations about the pathophysiology of the energy-producing mechanisms and their expected exercise limitation. METHODS: Twelve TM patients with no clinical evidence of cardiac or respiratory disease and 10 healthy subjects performed incremental, symptom-limited cardiopulmonary exercise testing (CPET) and submaximal, constant workload CPET. Oxygen uptake (VO2), carbon dioxide output and ventilation were measured breath-by-breath. RESULTS: Peak VO2 was reduced in TM patients (22.3 +/- 7.4 vs. 28.8 +/- 4.8 mL kg(-1) min(-1), P < 0.05) as was anaerobic threshold (13.1 +/- 2.7 vs. 17.4 +/- 2.6 mL kg(-1) min(-1), P = 0.002). There was no difference in oxygen cost of work at peak exercise (11.7 +/- 1.9 vs. 12.6 +/- 1.9 mL min(-1) W(-1) for patients and controls respectively, P = ns). Phase I duration was similar in TM patients and controls (24.6 +/- 7.3 vs. 23.3 +/- 6.6 s respectively, P = ns) whereas phase II time constant in patients was significantly prolonged (42.8 +/- 12.0 vs. 32.0 +/- 9.8 s, P < 0.05). CONCLUSION: TM patients present prolonged phase II on-transient oxygen kinetics during submaximal, constant workload exercise, compared with healthy controls, possibly suggesting a slower rate of high energy phosphate production and utilization and reduced oxidative capacity of myocytes; the latter could also account for their significantly limited exercise tolerance.

Variations of ferritin levels over a period of 15 years as a compliance chelation index in thalassemic patients.

We studied the changing pattern of the distribution of ferritin levels in 430 regularly-transfused patients with thalassemia in an attempt to evaluate compliance of chelation with deferoxamine. The study covered 15 years and was divided in three periods: 1981-1985, 1986-1990, and 1991-1995. The patients were stratified in age-groups. The mean ferritin levels of each period were calculated for each patient individually. The study showed that: (i) When all the patients were compared as a group, there was a significant decrease in mean ferritin between 1981-1985 and 1991-1995, despite a significant change in the patients' mean age; (ii) When patients of same age were compared between periods, there was a decrease in mean ferritin between 1981-1985 and 1991-1995, as well as a decrease in the proportion of patients with ferritin >4000 microg/L, with a parallel increase in the proportion of patients who had ferritin <2000 microg/L; (iii) When the same patients were followed longitudinally, they showed a decrease in their ferritin levels in all age groups with the exception of the late adolescence period. The decrease in iron overload observed in patients on close follow up implies that compliance with chelation therapy has improved with time and therefore, a favourable influence in survival could be expected.

Red cell alloantibodies in patients with thalassemia.

We present the results of tests carried out to detect alloimmunization against red cells in 1,200 patients (607 males and 593 females), transfused and followed up during the period 1981-1987 in our hospital. Of these patients, 1,135 were thalassemic and 65 had sickle cell/beta-thalassemia. In 162 patients who received blood matched for the AB0, rhesus and Kell systems from their first transfusion, the immunization rate was very low (3.7%). In a pilot group consisting of 83 patients with the same clinical characteristics, who received blood matched only for the AB0 and Rh-D antigens, there was a significant difference in the frequency of alloantibodies (15.7%, p less than 0.001). Of 1,038 patients who received blood only matched for AB0 and Rh-D 244 (23.5%) with one or more red cell alloantibodies were identified. Of these 1,038 patients, 973 were exclusively thalassemic. In 220 (22.6%) of them, alloantibodies were found. The sickle cell beta-thalassemia patients presented alloantibodies with a higher frequency (36.9%, 24/65). Only one antibody was found in 114 patients (51.8%) and two or more in 106 patients (48.2%). The alloimmunization significantly concerned the rhesus (34.0%) and Kell (29.8%) systems. Anti-Kell was most often identified (28.5%). Alloimmunization appears considerably lower in patients in whom blood transfusion is started before the age of 3 than in those in whom it is started after that age (20.9 vs. 47.5%, p less than 0.0001).

Serum erythropoietin in regularly transfused thalassemic patients.

Serum erythropoietin levels were measured in 67 regularly transfused thalassemic patients with pre-transfusion hematocrit ranging from 25-32% and in 40 normal individuals. In patients, mean erythropoietin levels were slightly increased (mean 91.5 miu/ml) as compared to normal individuals (mean 42 miu/ml). The distribution of erythropoietin (Ep) was wide in thalassemic patients. 40% had normal or decreased and 60% increased Ep levels. A reverse relation between pretransfusion Hct and erythropoietin activity was observed only among patients with normal erythropoietin levels and splenectomized patients with high erythropoietin titers suggesting that a normal feedback between tissue hypoxia and erythropoietin activity occurs in these groups. The effect of regular blood transfusions in reversing tissue hypoxia resulting from anemia in the majority of regularly transfused thalassemic patients seems to be satisfactory, as it is assessed by serum erythropoietin levels.

The impact of neocyte transfusion in the management of thalassaemia.

Transfusional iron overload leading to cardiopathy and other severe complications continues to be a major problem in chronically transfused homozygous beta-thalassaemia patients. It is well known that young red cells (neocytes) survive longer after transfusion and therefore may contribute to the extension of the intervals between transfusions. We evaluated the impact of neocytes in the total annual blood requirements and consequently the transfusional iron load in 18 thalassaemia patients. A two-period study comparing transfusions of standard red cells versus neocytes in the same group of patients was performed. Neocytes were harvested by density separation using the Neocel System. The method of preparation was simple with relatively low costs and required no special equipment. There was a significant difference (p < 0.005) in PK and MCV values of the neocyte and older red cell (gerocyte) fractions indicating that a good separation of the two populations was achieved. All patients had a reduction in blood requirements during the neocyte period. The total annually transfused red blood cells and concomitant iron blood load were significantly reduced (p < 0.001) by 20.2 +/- 9.1%. However, the response was variable. Seven of the 18 patients had a large reduction in blood consumption (24.8-34.8%), 9 others ranged between 10.7 and 21.6%, and in 2 the reduction was less than 10%. This reduction in blood requirements and in the transfused iron may change the chelation index resulting in more efficient iron chelation therapy and perhaps reduce the cost of the haemochromatosis therapy on a long-term basis. We conclude that the use of neocyte therapy using this system can benefit the majority of chronically transfused patients by reducing transfusional iron overload and related complications and may lead to a much better quality of life.

Molecular characterization of homozygous (high HbA2) beta-thalassemia intermedia in Greece.

Homozygous beta-thalassemia is usually characterized by severe anemia requiring regular blood transfusion for survival. For homozygous patients with milder clinical manifestations and no dependence on transfusion therapy, the term thalassemia intermedia is usually applied. Genetic mechanisms that may ameliorate the clinical expression of homozygous beta-thalassemia include coinheritance of alpha-thalassemia, inheritance of mild beta-globin gene mutations, and increased gamma-globin chain production, which may partially compensate for the lack of beta-globin chain synthesis. To identify which of these factors may contribute to the modification of childhood homozygous, high-hemoglobin A2 (HbA2) beta-thalassemia in Greece, the interaction of alpha-thalassemia, types of beta-thalassemia mutations, and the presence of a polymorphic site 5' to the G gamma-globin gene, which has been described as associated with increased gamma-globin chain production in some cases, was assessed. The results were analyzed in light of similar studies in 150 randomly selected, homozygous, high-HbA2 beta-thalassemia patients with the aim of assessing whether thalassemia genotypes can provide information useful for prognosis and/or more appropriate management of homozygous beta-thalassemia patients. The results indicate that, in general, the major factor modifying the clinical expression of homozygous, high-HbA2 beta-thalassemia in Greece is the inheritance of mild beta-thalassemia mutations. Although there is not always a complete correlation of genotype with clinical phenotype, the inheritance of two mild beta-thalassemia alleles results in almost all cases (11 of 12 cases in this study) in thalassemia intermedia phenotype.(ABSTRACT TRUNCATED AT 250 WORDS)

Prevalence of yersinia plasmid-encoded outer protein (Yop) class-specific antibodies in multitransfused Greek patients with thalassemic syndromes.

OBJECTIVE: To evaluate the prevalence of class-specific antibodies (G, A, M) to Yersinia enterocolitica plasmid-encoded outer proteins (Yops), in a closely followed multitransfused population of patients with thalassemia. METHODS: Sera from 408 beta-thalassemic patients and 386 healthy blood donors used as controls were analyzed with the enzyme-linked immunosorbent assay (ELISA) for IgG, IgA and IgM antibodies to yersinia outer proteins. The Yop antigen for the ELISA was prepared using a plasmid-bearing wild-type strain of Y. enterocolitica of serotype O:8. RESULTS: Anti-Yop IgG antibodies were detected in 84 out of 408 beta-thalassemic patients (20.6%) compared with only eight out of 386 (2.1%) healthy blood donors. None of the sera of either group was positive for anti-Yop IgA or IgM antibodies. On evaluating patients with registered clinical and laboratory signs of a previous yersinia infection in the period from 1978 to 1996, we found that those with a positive agglutination test for Y. enterocolitica infection at the time of manifestation showed a higher rate of persisting IgG seropositivity to Yops than those with positive culture and clinical signs only. A significant percentage (9.49%) of the seropositive patients had no registered data of a past Y. enterocolitica infection. There was remarkable persistence of anti-Yop IgG antibodies in the thalassemic population, even in patients infected during the early years of our study period (1978--80). CONCLUSIONS: The results suggest that the determination of class-specific antibodies to Yops, which are specific antigens for the pathogenic yersiniae (Y. enterocolitica, Y. pseudotuberculosis and Y. pestis), in addition to its usefulness in the diagnosis of infection, will be a very sensitive and specific index for epidemiologic studies.

The clinical phenotype of beta and delta beta thalassemias in Greece.

Based on precise evaluation of hematological findings and clinical manifestations, the relationship between genotype and clinical phenotype was studied in 475 Greek patients with beta and delta beta thalassemias. Almost all known genotypes are included in this series, but the most frequent was homozygous beta th high A2 (71.6%), beta th/beta th silent (7.4%), beta th/delta beta oth high F (6.3%) and beta th/beta th Dutch (6.3%). In general, the phenotype was related to the genotype, though clinical heterogeneity was detected among patients with the same genotype. The severe type of thalassemia major was most commonly found in homozygous beta th patients mainly of beta o/beta o and beta o/beta + genotypes while homozygous beta + patients had milder clinical manifestation. Furthermore a small group of patients, characterized as homozygous beta ++ (HbF less than 30%) had mild thalassemia intermedia. In addition mild thalassemia intermedia was principally related with homozygous delta beta oth, and compound heterozygous beta th/beta th silent I, and less frequently with other genotypes such as compound heterozygous with beta th/beta th Dutch, beta th/beta th silent II, beta th/delta beta oth high F or Lepore. It was shown that precise genetic characterization and clinical evaluation is of primary importance in predicting the prognosis and formulating the proper treatment for the individual patient with thalassemia.