Differential effects of iron chelators on iron burden and long-term morbidity and mortality outcomes in a large cohort of transfusion-dependent ß-thalassemia patients who remained on the same monotherapy over 10 years.

We conducted a retrospective cohort study on 663 transfusion-dependent ß-thalassemia patients receiving the same iron chelation monotherapy with deferoxamine, deferiprone, or deferasirox for up to 10 years (median age 31.8 years, 49.9 % females). Patients on all three iron chelators had a steady and significant decline in serum ferritin over the 10 years (median deferoxamine: -170.7 ng/mL, P = 0.049, deferiprone: -236.7 ng/mL, P = 0.001; deferasirox: -323.7 ng/mL, P < 0.001) yet had no significant change in liver iron concentration or cardiac T2*; while noting that patients generally had low hepatic and cardiac iron levels at study start. Median absolute, relative, and normalized changes were generally comparable between the three iron chelators. Patients receiving deferasirox had the highest morbidity and mortality-free survival probability among the three chelators, although the difference was only statistically significant when compared with deferoxamine (P = 0.037). On multivariate Cox regression analysis, there was no significant association between iron chelator type and the composite outcome of morbidity or mortality. In a real-world setting, there is comparable long-term iron chelation effectiveness between the three available iron chelators for patients with mild-to-moderate iron overload.

Revisiting iron overload status and change thresholds as predictors of mortality in transfusion-dependent ß-thalassemia: a 10-year cohort study.

Data on iron overload status and change thresholds that can predict mortality in patients with transfusion-dependent ß-thalassemia (TDT) are limited. This was a retrospective cohort study of 912 TDT patients followed for up to 10 years at treatment centers in Italy (median age 32 years, 51.6% female). The crude mortality rate was 2.9%. Following best-predictive threshold identification through receiver operating characteristic curve analyses, data from multivariate Cox-regression models showed that patients with Period Average Serum Ferritin (SF) > 2145 vs ≤ 2145 ng/mL were 7.1-fold (P < 0.001) or with Absolute Change SF > 1330 vs ≤ 1330 ng/mL increase were 21.5-fold (P < 0.001) more likely to die from any cause. Patients with Period Average Liver Iron Concentration (LIC) > 8 vs ≤ 8 mg/g were 20.2-fold (P < 0.001) or with Absolute Change LIC > 1.4 vs ≤ 1.4 mg/g increase were 27.6-fold (P < 0.001) more likely to die from any cause. Patients with Index (first) cardiac T2* (cT2*) < 27 vs ≥ 27 ms were 8.6-fold (P < 0.001) more likely to die from any cause. Similarly, results at varying thresholds were identified for death from cardiovascular disease. These findings should support decisions on iron chelation therapy by establishing treatment targets, including safe iron levels and clinically meaningful changes over time.

'Phenoconversion' in adult patients with ß-thalassemia.

Rate and risk factors for phenoconversion from non-transfusion-dependent ß-thalassemia (NTDT) to transfusion-dependent ß-thalassemia (TDT) during a 10-year follow up of adult patients in Italy.

Incidence of cancer and related deaths in hemoglobinopathies: A follow-up of 4631 patients between 1970 and 2021.

BACKGROUND: The correlation between thalassemia and malignancies other than hepatocellular carcinoma (HCC) and the possible relationship between other hemoglobinopathies and tumor risk have been poorly evaluated. METHODS: Eight Italian specialized centers evaluated the incidence of malignant neoplasms in hemoglobinopathies as well as their sites and features. The study cohort included 4631 patients followed between 1970 and 2021 (transfusion-dependent ß-thalassemia, 55.6%; non-transfusion-dependent thalassemia, 17.7%; sickle cell disease, 17.6%; hemoglobin H disease, 8.3%). RESULTS: A total of 197 diagnoses of cancer were reported (incidence rate, 442 cases per 100,000 person-years). The liver was the most frequent site of tumors in both sexes, with a higher incidence (190 cases per 100,000 person-years) in comparison with the general population found in all types of hemoglobinopathies (except hemoglobin H disease). In recent years, tumors have become the second cause of death in patients with transfusion-dependent thalassemia. A lower risk of breast and prostate cancer was observed in the whole group of patients with hemoglobinopathies. The first cancer diagnoses dated back to the 1980s, and the incidence rate sharply increased after the 2000s. However, although the incidence rate of cancers of all sites but the liver continued to show an increasing trend, the incidence of HCC showed stability. CONCLUSIONS: These findings provide novel insights into the relationship between cancer and hemoglobinopathies and suggest that the overall risk is not increased in these patients. HCC has been confirmed as the most frequent tumor, but advances in chelation and the drugs that have led to the eradication of hepatitis C may explain the recent steadiness in the number of diagnoses that is reported here.

Thalassaemia is paradoxically associated with a reduced risk of in-hospital complications and mortality in COVID-19: Data from an international registry.

Although numerous patient-specific co-factors have been shown to be associated with worse outcomes in COVID-19, the prognostic value of thalassaemic syndromes in COVID-19 patients remains poorly understood. We studied the outcomes of 137 COVID-19 patients with a history of transfusion-dependent thalassaemia (TDT) and transfusion independent thalassaemia (TIT) extracted from a large international cohort and compared them with the outcomes from a matched cohort of COVID-19 patients with no history of thalassaemia. The mean age of thalassaemia patients included in our study was 41 ± 16 years (48.9% male). Almost 81% of these patients suffered from TDT requiring blood transfusions on a regular basis. 38.7% of patients were blood group O. Cardiac iron overload was documented in 6.8% of study patients, whereas liver iron overload was documented in 35% of study patients. 40% of thalassaemia patients had a history of splenectomy. 27.7% of study patients required hospitalization due to COVID-19 infection. Amongst the hospitalized patients, one patient died (0.7%) and one patient required intubation. Continuous positive airway pressure (CPAP) was required in almost 5% of study patients. After adjustment for age-, sex- and other known risk factors (cardiac disease, kidney disease and pulmonary disease), the rate of in-hospital complications (supplemental oxygen use, admission to an intensive care unit for CPAP therapy or intubation) and all-cause mortality was significantly lower in the thalassaemia group compared to the matched cohort with no history of thalassaemia. Amongst thalassaemia patients in general, the TIT group exhibited a higher rate of hospitalization compared to the TDT group (p = 0.001). In addition, the rate of complications such as acute kidney injury and need for supplemental oxygen was significantly higher in the TIT group compared to the TDT group. In the multivariable logistic regression analysis, age and history of heart or kidney disease were all found to be independent risk factors for increased in-hospital, all-cause mortality, whereas the presence of thalassaemia (either TDT or TIT) was found to be independently associated with reduced all-cause mortality. The presence of thalassaemia in COVID-19 patients was independently associated with lower in-hospital, all-cause mortality and few in-hospital complications in our study. The pathophysiology of this is unclear and needs to be studied in vitro and in animal models.

Delta-globin gene expression improves sickle cell disease in a humanised mouse model.

Sickle cell disease (SCD) is a widespread genetic disease associated with severe disability and multi-organ damage, resulting in a reduced life expectancy. None of the existing clinical treatments provide a solution for all patients. Gene therapy and fetal haemoglobin (HbF) reactivation through genetic approaches have obtained promising, but early, results in patients. Furthermore, the search for active molecules to increase HbF is still ongoing. The delta-globin gene produces the delta-globin of haemoglobin A2 (HbA2). Although expressed at a low level, HbA2 is fully functional and could be a valid anti-sickling agent in SCD. To evaluate the therapeutic potential of a strategy aimed to over-express the delta-globin gene in vivo, we crossed transgenic mice carrying a single copy of the delta-globin gene, genetically modified to be expressed at a higher level (activated), with a humanised mouse model of SCD. The activated delta-globin gene gives rise to a consistent production of HbA2, effectively improving the SCD phenotype. For the first time in vivo, these results demonstrate the therapeutic potential of delta-globin, which could lead to novel approaches to the cure of SCD.

Hematological phenotypes in children according to the α-globin genotypes.

Limited information is available on the hematological characterization of the α-thalassemia carrier in pediatric age. The objective of this report was to evaluate the red cell indices according to the α-globin genotype in a cohort of children evaluated in Sardinia. Moreover, we verified the frequency of different α-globin genotypes in this cohort. A total of 453 subjects were investigated for hematological indices and for the most common α-globin defects present in Sardinia. Of them, 352 with HbA2≤3.2%, and no iron deficiency anemia were taken into consideration to evaluate the red cell indices according to the α-globin genotype in pediatric age. A total of 11 different α-genotypes were detected, confirming the wide heterogeneity of α-thalassemia in Sardinia. Moreover, our results showed that the hematological parameters in normal children may be conditioned by the clinically occult coinheritance of mild α-thalassemia alleles as already described in the adult population while microcytosis and hypocromia in children without iron deficiency should suggest the coexistence of two α-globin defects. We concluded that recognizing the α-globin gene mutations for a particular population with their particular red cell indices may help pediatricians to perform a correct diagnosis distinguishing among physiological and pathological types of microcytosis and hypocromia.

Changes in HbA2 and HbF in alpha thalassemia carriers with KLF1 mutation.

α-thalassemia carriers are common in Mediterranean regions, particularly in the Sardinian population. Their haematological phenotype is characterized by reduced MCV and/or MCH with normal or slightly reduced HbA2 levels and normal HbF. Krüppel-like factor 1 (KLF1) is a pleiotropic erythroid transcription factor that is essential for haematopoiesis. Mutations in the KLF1 gene trigger a series of benign human red blood phenotypes, such as an increase in HbA2 and HBF. Recently, it has been found that KLF1 mutations were a frequent cause of borderline HbA2 levels in a group of Sardinian subjects. Here, we found that KLF1 mutations modulate the phenotype in a cohort of α-thalassemia carriers.

The Problem of Borderline Hemoglobin A2 Levels in the Screening for ß-Thalassemia Carriers in Sardinia.

BACKGROUND: The increase in HbA2 is the most important parameter for the identification of thalassemia carriers. However, in routine screening for hemoglobinopathies, some cases are difficult to classify because the level of HbA2 is not typically elevated. In this work, we report the results of a molecular investigation on a cohort of subjects with borderline HbA2. METHODS: All subjects with a ß-thalassemia carrier partner and a borderline percentage level of HbA2 were investigated for the presence of a pathological mutation in the ß-globin gene. All negative subjects were screened for both the KLF1 mutation and the presence of ααα/ or αααα/ alleles. The subjects with reduced MCV and/or MCH were also screened for deletional and nondeletional α-globin gene defects. RESULTS: Various ß-globin mutations and KLF1 gene defects are the most common genetic determinants responsible for this phenotype in our population. CONCLUSION: KLF1 mutations are important in a screening program for hemoglobinopathies. An increase in HbF in association with borderline HbA2 levels is a useful but not exclusive marker that suggests the investigation of this gene. On the basis of our findings, we are able to suggest the molecular procedure to use in a population characterized by a high prevalence of thalassemia carriers.

Hepatocellular carcinoma in thalassaemia: an update of the Italian Registry.

The risk of developing hepatocellular carcinoma (HCC) in patients with thalassaemia is increased by transfusion-transmitted infections and haemosiderosis. All Italian Thalassaemia Centres use an ad hoc form to report all diagnoses of HCC to the Italian Registry. Since our last report, in 2002, up to December 2012, 62 new cases were identified, 52% of whom were affected by thalassaemia major (TM) and 45% by thalassaemia intermedia (TI). Two had sickle-thalassaemia (ST). The incidence of the tumour is increasing, possibly because of the longer survival of patients and consequent longer exposure to the noxious effects of the hepatotropic viruses and iron. Three patients were hepatitis B surface antigen-positive, 36 patients showed evidence of past infection with hepatitis B virus (HBV). Fifty-four patients had antibodies against hepatitis C virus (HCV), 43 of whom were HCV RNA positive. Only 4 had no evidence of exposure either to HCV or HBV. The mean liver iron concentration was 8 mg/g dry weight. Therapy included chemoembolization, thermoablation with radiofrequency and surgical excision. Three patients underwent liver transplant, 21 received palliative therapy. As of December 2012, 41 patients had died. The average survival time from HCC detection to death was 11·5 months (1·4-107·2 months). Ultrasonography is recommended every 6 months to enable early diagnosis of HCC, which is crucial to decrease mortality.

Complexity of the alpha-globin genotypes identified with thalassemia screening in Sardinia.

α-Thalassemia commonly results from deletions or point mutations in one or both α-globin genes located on chromosome 16p13.3 giving rise to complex and variable genotypes and phenotypes. Rarely, unusual non-deletion defects or atypical deletions down-regulate the expression of the α-globin gene. In the last decade of the program for ß-thalassemia carrier screening and genetic counseling in Sardinia, the association of new techniques of molecular biology such as gene sequencing and Multiplex Ligation-dependent Probe Amplification (MLPA) to conventional methods has allowed to better define several thalassemic genotypes and the complex variability of the α-cluster with its flanking regions, with a high frequency of different genotypes and compound heterozygosity for two α mutations even in the same family. The exact molecular definition of the genotypes resulting from the interactions among the large number of α-thalassemia determinants and with ß-thalassemia, is important for a correct correlation of genotype-phenotype and to prevent underdiagnosis of carrier status which could hamper the effectiveness of a screening program particularly in those regions where a high frequency of hemoglobinopathies is present.