Clinical significance of mutational variants in beta and alpha genes in patients with hemoglobinopathies from two large Greek centers: a complex interplay between genotype and phenotype

Hemoglobinopathies affect patients in the wider Mediterranean area consisting of 4 distinct subgroups: beta thalassemia major (TM), beta thalassemia intermedia (TI), sickle cell disease (SCD) and hemoglobin H disease (alpha thalassemia). The clinical spectrum varies from mild to severe. Complex interactions between genes and environmental factors form the clinical manifestations. There is an unmet need to clarify these multifactorial mechanisms. This is the first Greek study describing mutational alleles (HBB and HBA1/HBA2 gene variants) in 217 patients with hemoglobinopathies of two large centers in Greece (Larissa and Athens) and associating particular genotypes or gene variants with clinical manifestations (transfusion frequency, complications). Thus, the complex interplay between corresponding genotypes and phenotypes was investigated. Our results are in accordance with previous national studies with limited variations, due to regional prevalence of specific gene variants, as expected. It is also a description of the prevalence of hemoglobinopathies in the Greek population. The type and prevalence of beta and alpha globin gene variants differ significantly among countries. We also confirm the well-known observation of many studies that in our beta thalassemic or SCD patients, co-inheritance of variants in the alpha globin genes, leading to absence or reduction of alpha globin synthesis were associated with milder clinical course, whereas the inheritance of additional alpha genes (triplication) led to a more severe clinical phenotype. In cases in whom the genotype and phenotype did not correlate, factors like the function or modification of possible regulatory genes or additional nutritional-environmental effects should be investigated. KEY MESSAGES: • This is the first Greek study, fully molecularly defining the beta and alpha mutational alleles in 217 patients with hemoglobinopathies of two large centers in Greece and correlating particular genotypes or gene variants with clinical manifestations (transfusion frequency, complications). • In the beta thalassemic or SCD patients of our cohort, co-inheritance of variants in the alpha globin genes, leading to absence or reduction of alpha globin synthesis were associated with milder clinical course (confirmation of a well-known previous observation). • The inheritance of additional alpha genes (triplication) led to a more severe clinical phenotype (confirmation of a well known previous observation). • The function or modification of possible regulatory genes should be investigated in cases in whom the genotype and phenotype did not correlate.

Characteristics and Prognosis of Hepatocellular Carcinoma in Multi-Transfused Patients with β-Thalassemia. Experience of a Single Tertiary Center

Background/Aim

The incidence of hepatocellular carcinoma (HCC) in patients with transfusion dependent thalassemia (TDT) has been increasing, where viral hepatitis and iron overload are the two established HCC risk factors. The aim of this study was to investigate the etiological factors of HCC development and to evaluate the possible factors associated with survival in our cohort of TDT patients with HCC.

Methods

Records of patients with TDT diagnosed with HCC from 2008 to 2018 were reviewed. Liver iron concentration (LIC) has been assessed by the signal-intensity-ratio MRI. The diagnosis of HCC was made by a 3-phase contrast magnetic resonance imaging (MRI) and patients were staged and treated for HCC according to Barcelona Clinic Liver Cancer (BCLC) grading system.

Results

Forty-two TDT patients with HCC have been included. Most of them (78.5%) were anti-HCV positive, 59.5% HCV-RNA positive, and 16.5% had serological markers of resolved HBV infection. Patients with HCV infection have been treated successfully with either Peg-IFNa±Ribavirin or with the new direct antivirals (DAAs). At the time of HCC diagnosis, all patients with chronic HCV infection were HCV-RNA negative, 78.5% had underlying cirrhosis, and the vast majority (98%) had average or mild elevated LIC values. According to the BCLC system, patients were classified as 0-A: 28.5%, B: 57% and C-D: 14.5%. HCC has been treated with loco-regional treatment in 78.5% of our patients, while the rest have received sorafenib. Twenty-eight patients (66.5%) died due to HCC with a median survival time of 6 months (range: 2-60). Using the Cox proportional hazard model, the only factors associated with poor survival were BCLC stages C and D.

Conclusions

In conclusion, BCLC staging is the main prognostic factor of survival in patients with TDT who develop HCC.

Comparison of Doppler echocardiographic and tissue Doppler velocity data in beta-thalassaemia major with high and normal NT-proBNP levels of children in the south-east region of Turkey

BACKGROUND

It has been reported that N-terminal pro-brain natriuretic peptide (NT-proBNP) is early biomarker of iron- induced cardiomyopathy in β-thalassemia major (β-TM). In this study, we aimed to assess the Doppler echocardiographic, tissue Doppler velocity datas and clinical characteristics in β-TM patients with high and normal NT-proBNP levels who have normal systolic function.

MATERIAL AND METHOD

Fifty-eight β-TM patients who were on regular transfusion in every 3-4 weeks for more than one year and 20 healthy children were included into the study. According to NT-proBNP levels, β-TM patients are divided in two groups. Group I: the patients with high NT-proBNP levels; Group II: the patients with normal NT-proBNP levels.

RESULTS

The mean serum NT-proBNP levels were significantly increased in patients with β-TM compared to control group (P<0.05). The serum ferritin levels were ranged between 676-9,476 ng/mL (mean: 3,716±2,003 ng/mL) in β-TM. No correlation was found between ferritin and NT-pro BNP in patients with β-TM. The mean age and body surface area (BSA) were significantly low in group with high NT-proBNP compared to group with normal NT-proBNP (P<0.01). The mean heart rate, systolic blood pressure (SBP) and diastolic blood pressure (DBP) were elevated, but not significantly in group with high NT-proBNP. Also, the mean ferritin and hemoglobin levels were decreased in this group compared to group with normal NT-proBNP, but statistically not significant. The left ventricular end diastole (LVED) diameters and left ventricular mass index (LVMI) values were found significantly decreased in group with high NT-proBNP compared to other group respectively (P<0.001, P<0,05). Right ventricular early diastolic tricuspid inflow velocity/early diastolic tissue Doppler indices (TDI) tricuspid annular velocity (RV E/E') were found increased in group with high NT-proBNP levels and difference was statistically significant (P<0.05). In addition, NT-pro BNP was found correlated with RV E/E' (r: 0.320).

CONCLUSIONS

According to our result, elevated NT-proBNP level was correlated with RVE/E', but it was not associated with ferritin level. The serum NT-proBNP level may be increased as a response to increased myocardial workload and decreased hemoglobin level in patients who have an increased need for transfusion.