Cardiac amyloidosis is not a single disease: a multiparametric comparison between the light chain and transthyretin forms

Background

Systemic amyloidoses represent a heterogeneous group of diseases resulting from the deposition of misfolded proteins as amyloid fibrils into the extracellular matrix of different organs. Based on this precursor protein, cardiac amyloidosis (CA) can be most frequently classified as: light chain (AL) and transthyretin (ATTR) amyloidosis, with different management and prognosis.

Purpose

The purpose of this study is to establish a differential diagnosis algorithm targeted towards these two most frequent subtypes of CA. Although confirmation through invasive or non-invasive diagnostic algorithms is still mandatory for a final diagnosis, a series of clinical, paraclinical and imaging differences could possibly guide the choice for more complex diagnostic steps.

Methods

We prospectively included all consecutive patients with ATTR and AL evaluated between 2018 and 2022 in our center. All patients had a complete clinical, paraclinical and imaging evaluation including myocardial deformation study, and confirmation of the final diagnosis, according to the current international recommendations.

Results

The study population included 81 patients divided into 2 groups: ATTR (group 1, n=32: 30 variant and 2 wild type) and AL (group 2, n=49).

ATTR patients were younger (50.7±13.9 vs. 60.2±7.3 years, p=0.0001), had predominantly more neurological symptoms, milder cardiac symptoms and lower values of cardiac biomarkers than AL: NT-proBNP (3095±4433 vs. 10382±9008 ng/ml, p=0.001) and high sensitive troponin I (0.0129±0.01 vs 0.177±0.2 ng/ml, p=0.0002), with better renal function (mean GFR 84.74±26.9 vs. 64.5±29.45 mL/min, p=0.003). We found no significant differences in terms of ECG changes.

Moreover, at similar left ventricular (LV) wall thickness and ejection fraction, ATTR group had less pericardial effusions (53.6 vs. 86.8%, p=0.0027), better LV global longitudinal strain (−12.0±3.7 vs. −9.7±4.6%, p=0.03), RV strain (RVFW strain −19.7±6.2 vs. −14.5±11.0%, p=0.03) and also better reservoir and contractile function of the LA (LASr 17.2±12.3 vs. 11.2±7.4%, p=0.02).

Based on this multiparametric comparison we proposed a prediction algorithm to differentiate between the 2 forms of CA. A score of equal or more than 4 from a maximum of 9 points, has been able to differentiate between AL and ATTR with a sensitivity and specificity of 78 and 80%, respectively; AUC= 0.82.

Conclusions

CA is a complex entity and requires extensive testing through serum biomarkers, imaging, and invasive confirmation of amyloid infiltration in some cases. This study highlighted a series of non-invasive checkpoints, which can be useful in guiding the decision making process towards a more accurate and rapid differential diagnosis, in cases where a final diagnosis is crucial to be immediately established.

Funding Acknowledgement

Type of funding sources: None.

P216 Cardiac amyloidosis is not a single disease: an echocardiographic study of light chain vs transthyretin forms

Background

Cardiac amyloidosis (CA) is described as one entity. However, several subtypes of amyloid can infiltrate the heart: light chain (AL) and tranthyretin (ATTR) are the most common.

Purpose

To characterize the specific findings of the CA subtypes as a tool to aid differential diagnosis between AL and ATTR CA.

Material and methods: Consecutive patients with CA were evaluated by clinical examination, ECG, cardiac biomarkers and echocardiography with both conventional and myocardial deformation study of the left ventricle (LV), left atrium (LA) and right ventricle (RV). Amyloid subtype was described using light chain assessment for AL-CA and 99Tc-HMPD scintigraphy and TTR gene sequencing for ATTR-CA.

Results

32 patients with CA were included, 13 with ATTR and 19 with AL. Patients in AL group were significantly older, with higher levels of cardiac biomarkers. At similar LV EF and wall thickness, they had lower GLS. LA function parameters were also lower in AL pts (table). Using ROC curves, the best predictors for AL diagnosis were NTproBNP (AUC 0.937) and Tn levels (AUC 0.958), as well as LV GLS and pericardial fluid presence (both AUC 0.750).

Conclusions

At similar LV wall thickness and ejection fraction, cardiac dysfunction appears to be more severe in AL pts, with lower global LV longitudinal strain, worse LA function, higher sPAP and NTproBNP.

ATTR (13 pts) AL (19 pts) p Age (years) 50 ± 12 60 ± 8 0.01 NTproBNP (pg/mL) 3066 ± 3720 11755 ± 9114 0.02 hsTnI (ng/mL) 0.005 ± 0.008 0.147 ± 0.161 0.04 Pericardial fluid (%) 53% 100% 0.002 LVEDV (mL) 88 ± 25 75 ± 38 NS LVMi (g/m2) 166 ± 47 168 ± 41 NS LVEF (%) 50 ± 8 49 ± 16 NS LV GLS (%) -12.1 ± 3.8 -8.9 ± 4.5 0.04 Septal Basal/Apical LS 0.33 ± 0.17 0.25 ± 0.27 NS LAVi (mL/m2) 46 ± 21 45 ± 14 NS LAEF 4CV (%) 35 ± 21 24 ± 8 0.05 LA systolic strain (%) 17.4 ± 11.9 10.5 ± 5.0 0.02 RV free wall thickness (mm) 7.0 ± 1.5 7.6 ± 1.4 NS RV 6-segments strain (%) -15 ± 4 -10 ± 8 0.09 sPAP (mmHg) 36.6 ± 12.0 48.6 ± 17.2 0.04

The impact of additional cytogenetic abnormalities at diagnosis and during therapy with tyrosine kinase inhibitors in Chronic Myeloid Leukaemia

BACKGROUND

Chronic Myeloid Leukemia's (CML) treatment was optimized since the development of tyrosine kinase inhibitors (TKI) and an increased overall survival during TKI was noticed. During the TKI era, protocols for assessing response and resistance to treatment were developed. Additional chromosomal abnormalities (ACAs) are strongly associated with disease progression but their prognostic impact and influence on treatment response are yet to be defined. The aim of this study was to analyze the impact of ACAs on time to achieve complete cytogenetic response (CCyR), treatment and overall survival.

MATERIALS AND METHODS

Since 2005 until 2013, the data from the Hematology and Bone Marrow Transplantation Department of Fundeni Clinical Institute was collected. In this observational retrospective single centre study, 28 CML patients with ACAs at diagnosis and during TKI treatment were included.

RESULTS

From ACAs at diagnosis group, the most frequent major route ACAs were trisomy 8, trisomy 19 and second Philadelphia (Ph) chromosome and the most frequent minor route ACAs were monosomies and structural abnormalities (inversions and translocations). From the ACAs during the TKI group, the most frequent major route cytogenetic abnormalities in Ph positive and negative cells were trisomy 8, trisomy 19 and second Ph chromosome and the most frequent minor route cytogenetic abnormalities in Ph positive and negative cells were marker chromosomes and structural abnormalities (inversions, translocations and dicentric chromosomes).

CONCLUSIONS

In both groups, the time to CCyR was longer and long-term results were inferior in comparison with standard patients but the differences were not significant and in accordance to published data. The 12 months follow-up after the study's end showed that 26 patients were alive and in long-term CCyR and 2 deaths were reported.

ABBREVIATIONS

CML = Chronic Myeloid Leukemia, BCR-ABL1 = Break Cluster Region - Abelson gene, TKI = tyrosine kinase inhibitor treatment, ACAs = additional cytogenetic abnormalities, CCyR = complete cytogenetic response, PCyR = partial cytogenetic response, mCyR = minor cytogenetic response, MMR = major molecular response, HSCT = hematopoietic stem cell transplant, HLA = human leukocyte antigens, CP = chronic phase, AP = accelerated phase, BP = blast phase, OS = overall survival, CBA = chromosome banding analysis, +8 = trisomy 8, i(17q) = isochromosome (17q), +Ph = second Philadelphia chromosome, -7 = monosomy 7, -17 = monosomy 17, +17 = trisomy 17, -21 = monosomy 21, +21 = trisomy 21, -Y = loss of Y chromosome, ELN = European LeukemiaNet, IMA600 = Imatinib 600 mg daily, IMA400 = Imatinib 400 mg daily, NILO600 = Nilotinib 600 mg daily, DASA100 = Dasatinib 100mg daily, DASA140 = Dasatinib 140 mg daily.

Mucormycosis during Imatinib treatment: case report

Philadelphia chromosome positive acute lymphoblastic leukemia is classified as a very high-risk group and it requires an intensive chemotherapy regimen associated with tyrosine-kinase inhibitors and allogeneic hematopoietic stem cell transplant from related or unrelated HLA matched donor. Most times, intensive chemotherapy regimens are associated with prolonged and profound pancytopenia when the risk of invasive fungal infection increases. After Candida and Aspergillus species, Mucormycosis is the third frequent fungal infection in hematology patients and it is associated with a reduced overall survival. When suspected, immediate treatment is needed. We present the case of 24-year-old patient diagnosed with Philadelphia chromosome positive acute lymphoblastic leukemia who developed right rhino-sino-orbital fungal infection with a favorable response to systemic antifungal treatment and noninvasive surgery. Later, patient refused consolidation and allogeneic hematopoietic stem cell transplant from an unrelated HLA matched donor but accepted the first generation tyrosine kinase inhibitor (Imatinib) and maintained a complete hematological and molecular response.

ABBREVIATIONS

ENT = ear nose throat; BMB = bone marrow biopsy; ALL = acute lymphoblastic leukemia; TKI = tyrosine kinase inhibitor; IFI = invasive fungal infection; BMB = bone marrow biopsy; HE = hematoxylin and eosin; IHC = immunohistochemistry; CD = cluster of differentiation; ob = objective; Tdt = terminal deoxynucleotidyl transferase.

Hereditary Thrombophilia and thrombotic events in pregnancy: single-center experience

Pregnancy is a normal physiological state that predisposes to thrombosis, determined by hormonal changes in the body. These changes occur in the blood flow (venous stasis), changes in the vascular wall (hypotonia, endothelial lesion) and changes in the coagulation factors (increased levels of factor VII, factor VIII, factor X, von Willebrand factor) and decreased activity levels of natural anticoagulants (protein C, protein S). In this study, we tried to determine a possible association between thrombosis and inherited thrombophilia in pregnant women. This is a retrospective study of 151 pregnant women with a history of complicated pregnancy: maternal thrombosis and placental vascular pathology (intrauterine growth restriction, preeclampsia, recurrent pregnancy loss), who were admitted in our hospital during the period January 2010 to July 2014. We performed genetic analyses to detect the factor V Leiden mutation, the G20210A mutation in the prothrombin gene, the C677T mutation and the A1298C mutation in methylenetetrahydrofolate reductase (MTHFR) gene. The risk of thrombosis in patients with factor V Leiden is 2.66 times higher than the patients negative for this mutation (OR 2.66 95% CI 0.96-7.37 P=0.059). We did not find any statistical association with mutations in the MTHFR gene. Pregnant women with a family history of thrombosis present a 2.18-fold higher risk of thrombosis (OR 2.18 CI 0.9-5.26 P=0.085). Of 151 pregnant women, thrombotic events occurred in 24 patients: deep vein thrombosis, pulmonary embolism, cerebral venous sinus thrombosis and ischemic stroke. The occurrence of thrombotic events was identified in the last trimester of pregnancy, but especially postpartum. Thrombosis in pregnancy is a redoubtable complication requiring an excellent cooperation between the obstetrician and anesthesiologist.

The concomitant occurrence of JAK2V617F mutation and BCR/ABL transcript with phenotypic expression - an overlapping myeloproliferative disorder or two distinct diseases? - case report

The concomitant occurrence of JAK2617F mutation and BCR/ABL translocation is a rare event. It is unclear if this is a result of the clonal evolution or a separately emergence of two clones and if it could lead to the progression to a more aggressive phase of the disease. We present the case of a 61-year-old man diagnosed and treated for polycythaemia vera for 7 years, which evolved into chronic myeloid leukemia BCR/ABL positive and with JAK2617F mutated clone, that became dominant after an effective treatment with Imatinib.

Refractory anemia with ringed sideroblasts and thrombocytosis without JAK2 V617F mutation: report of three cases

In the WHO classification, there is a provisional entity called Myelodysplastic/Myeloproliferative Neoplasm, Unclassifiable (MDS/MPN, U). Refractory anemia with ringed sideroblasts associated with marked thrombocytosis (RARS-T) was included in this category. Recently published studies report a small percentage of patients with RARS-T. Sixty percent of these have JAK2 V617F mutation, which can suggest the coexistence of two pathological conditions (MDS and MPN). In this paper, we analyzed three patients diagnosed with RARS-T in the Department of Hematology, "Fundeni" Clinical Institute, Bucharest, Romania, during the period 2005-2011. The patients were investigated with cytogenetic exam and molecular biology. In these three cases were identified morphological features of multilineage dysplasia (two-lineage dysplasia in two cases and three-lineage dysplasia in one case). In two cases, thrombocytosis was under 1000×10(3)/μL and clinical evolution was similar to the myelodysplastic syndrome (transfusion dependent anemia with response to administration of erythropoietin). In the third case, the platelets were over 1000×10(3)/μL and with response to the treatment with Hydrea, which improved anemia. JAK2 V617F mutation was not identified in any case. RARS-T remains a provisional entity and requires a complex investigation of patients for the correct diagnosis of these patients. Therapeutic options should be personalized to each case in part because there is not yet a standardized treatment of these patients.

Importance of assessing cytogenetic and molecular risk factors in acute myeloid leukemia therapy

Acute myeloid leukemia (AML) is a heterogeneous disease in clinical presentation, outcome and therapeutic response. Cytogenetic and molecular characteristics are important prognostic indicators allowing the identification of distinct subtypes of AML, prognostic stratification and risk-adapted treatment. We present our experience during 5 years, in which we treated 245 patients with AML, of which we could genetically characterize 48 cases (26 females, 22 males) with a median age of 52 years. Cytogenetic analysis was performed by GTG banding on cultures of marrow cells treated with colcemid. Molecular analysis used RT-PCR performed on ABI 9700 platform in order to identify the following fusion genes: E2A-PBX1, TEL-AML1, AML1-ETO, PML-RARα, MLL-AF4, CBFC-MYH11, BCR-ABL, SIL-TAL, and MLL-AF9as well as mutations in Flt3, NPM1, WT1 genes. Fourteen patients were older than 60 years. In 12 we performed cytogenetic analysis showing 5 cases with complex karyotype, 2 normal karyotypes, 1 case of del(21), del (9), 11q- and t(3;15) respectively as well as 2 unevaluable karyotypes. These anomalies were associated with a high incidence of secondary AMLs (10/14) and with a low remission (CR) rate (5/14). Out of the 35 patients younger than 60 years, 25 were evaluated by cytogenetics showing a high incidence of favorable cytogenetic changes: 6 anomalies of chromosome 16 (5 inv (16) and 1 t (16; 16)), 3 t (15; 17), 3 cases of t (8; 21) of which 2 with additional abnormalities, 7 normal karyotypes and 1 case of 7q-, -y,-3 and respectively -8 associated with +18. In 25 cases molecular analysis was performed showing alterations in 21 patients: 6 cases with AML/ETO, 3 PML/RAR, 7 Flt3 mutations (2 associated with NPM1 mutation) as well as 1 case of isolated mutation of NPM1 and respectively WT1. CR rate was of 28/35. All cases with t (15; 17) and PML/RAR as well all cases with t (8; 21) and/or AML/ETO achieved CR. Out of the 7 cases with Flt3 mutations only 4 achieved CR including the 2 cases with associated NPM1 mutations. In our experience, genetic characteristics correlate with other prognostic markers such as age and secondary leukemia; "favorable" genetic anomalies were associated with a high CR rate; association of t (8; 21) with additional abnormalities did not influence CR rate.

Systemic mastocytosis associated with essential thrombocythemia

Mastocytosis comprises a spectrum of disorders characterized by abnormal growth of mast cells (MS). Four entities are recognizable according to WHO classification. Association of systemic mastocytosis (SM) with a chronic myeloproliferative neoplasia (SM-AHNMD) is the second frequently category. Published descriptions of the clinicopathologic features of SM-AHNMD are largely limited to individual case reports. We present the case of a 41-year-old woman with thrombocytosis and mild splenomegaly. Clinical suspicion was of chronic myeloproliferative neoplasia (CMN). Bone marrow trephine biopsy examination (histology and immunohistochemistry for CD117 and CD25) revealed a SM associated with CMN, essential thrombocythemia (ET) type. The JAK2 V617F (for CMN) was detected but KIT/Asp816Val (reported in ~80% of SM) was absent. We discussed the particularity of the cases correlated with a review of the literature.

Cytokine gene polymorphisms support diagnostic monitoring of Romanian multiple myeloma patients

INTRODUCTION

Cytokines and their receptor genes are very polymorphic. SNPs in the promotor region of the gene may influence the rate of cytokine secretion and may affect the biological activity of the encoded cytokine. A number of cytokines and cytokine receptors have been directly linked to the development of human cancers. The aim of our study was to determine the cytokine gene polymorphism in Romanian multiple myeloma patients.

MATERIAL AND METHODS

Cytokine genotyping was performed in 80 patients and 100 healthy blood donors using molecular biology methods (SSP-Invitrogen, USA).

RESULTS

Analyzing each polymorphic site, there was an increased frequency of the following genotypes in patients compared to control group: Interleukin-1beta (IL-1β) pos.+3962 TT, IL-12 pos.-1188 CC, gamma-Interferon (γ-IFN) pos.+874 AA, Transforming Growth Factor- beta1 (TGF- β1) codon10 TT, IL-2 pos.-330 TG and pos.+166 TT, Interleukin-4Receptor alpha (IL-4Rα) pos.-33 TC, IL-10 pos.-1082 GG and pos.-592 CC, IL-6 pos.-174 GG. It should be noted that almost one third of multiple myeloma patients had IL-6 pos.-174 GG genotype and 62% IL-10 GCC haplotype. These identified haplotypes are high interleukins producer, and this fact was confirmed by serum IL-6 and IL-10 levels performed by ELISA and enhanced chemiluminiscence methods.

CONCLUSION

These markers could be successfully used, together with other specific clinical and biological parameters, as reliable individualized prognostic factors in multiple myeloma patients.

Rhino-cerebral zygomycosis after allogeneic transplant: case report and literature review

The proportion of patients with hematological malignancies (HM) who develop rare invasive fungal infections (IFI) has increased worldwide over the past few decades. Zygomycosis is an opportunistic fungal infection, which begins in the nose and paranasal sinuses due to inhalation of fungal spores. Rhino-cerebral zygomycosis is the most common form of the disease, it typically develops in diabetic or immunocompromised patients and presents as an acute fulminate infection, which is often lethal. We report a case of rhino-cerebral zygomycosis in an allotransplanted patient to emphasize early diagnosis and treatment of this potentially fatal fungal infection. We discuss different risk factors, specific diagnosis procedures and review the current concepts in management of zygomycosis.

"In situ" mantle cell lymphoma associated with hyaline-vascular Castleman disease

Mantle cell lymphoma (MCL) is a very rare non-Hodgkin B-cell lymphoma, with an aggressive clinical course and poor response to conventional therapy. Few cases of "in situ" MCL were reported in the last years. We present the case of a 31-year-old woman with a unique cervical lymphadenopathy. The morphologic findings are of hyaline-vascular Castleman disease (HV-CD). Immunohistochemical stain for cyclin D1 detects scattered cyclin D1+ cells within the mantle zones of few reactive-appearing lymphoid follicles, corresponding to the definition of "in situ" MCL. We also performed cyclin D1 in other 27 cases of CD (13 HV-CD and 14 plasma-cell CD) but the reported case was the only who associated "in situ" MCL. An adequate immunohistochemical panel, including a marker for cyclin D1, is required to differentiate this neoplasm from follicular hyperplasia. From our knowledge, this is the first reported case of "in situ" MCL associated with HV-CD.

Chronic myeloid leukemia--from the National to the European Registry--limited experience of a single center

Chronic myeloid leukemia (CML) is a hematopoietic stem cell disorder in which the diagnosis is confirmed by detection of a genetic marker: Philadelphia (Ph) chromosome in almost 90% of cases. Some of Ph1 negative patients, nevertheless, test positive for the abnormal gene, or the abnormal protein associated with this chromosome, when more sensitive studies, such as PCR or FISH are used and nowadays the diagnosis of CML is based, not only on cytogenetic, but also on molecular analysis. The better understanding of the CML biology provided by the latest researches requires a deeper knowledge about the epidemiologic data in each geographic area, so the compiling of a National and/or European Registry for CML patients, that represents one of the aims of this study, became a stringent matter in our days; it can offer valuable data concerning the real incidence of this disease in Romania and can provide the basics for establishing long-term budgetary strategies.

Prenatal molecular diagnosis of beta-thalassemia: report on the first two cases in Romania

Thalassaemia major is a classical example of a disease that can be prevented by prenatal diagnosis. In Romania there are currently 300 patients with thalassaemia major under the management of specialized institutions. Prenatal diagnoses of thalassemia have offered a new dimension to the prevention of this disease, but in order to implement prenatal diagnosis, knowledge of mutations and of their incidence is essential. Molecular testing using Denaturing Gradient Gel Electrophoresis (DGGE) scanning and direct mutation detection with Amplificaton Refractory Mutation System-PCR (ARMS-PCR) and Restriction endonuclease Analysis of PCR fragments (PCR-RFLP) was performed by using amplified DNA from amniotic cells samples, while mutations in the parents were determined in advance. Using our experience in molecular diagnosis, we were able to perform the first prenatal diagnosis for two young couples at risk for thalassaemia major. Foetal samplings were collected by amniocentesis and chorionic villus sampling in the second trimester of the pregnancies. Maternal contamination of the foetal DNA was ruled out by STR genotyping. The prenatal diagnosis revealed affected foetuses with homozygous status of beta-thalassemia major. The IVSI-110 (G-A)/IVS II-745 (C-G) genotype in the first case foetus and ed 8 (-AA)/cd 8 (-AA) in the second case foetus were reported. The results of this study point to a successful future prenatal diagnosis of beta-thalassnemia in Romania, using a rapid and accurate molecular method. Together with the implementation of proper preventive health measures and the education of parents regarding their carrier status, we are hoping that this method will be used as the common application approach to decrease the incidence of thalassacmia major.

Compound heterozygosity for the C677T and A1298C mutations of the MTHFR gene in a case of hyperhomocysteinemia with recurrent deep thrombosis at young age

We report a case of a young woman with an extensive, recurrent deep vein thrombosis (DVT) diagnosed by CT scan and duplex ultrasound examination. All blood investigations for etiology of recurrent DVT were normal except for serum homocysteine level, which was mildly increased. No other thrombophilic factors could be found. The three main causes of hyperhomocysteinemia are genetic defects, nutritional deficiencies and insufficient elimination. In our case a genetic defect for one of the key enzymes of homocysteine metabolism was found to be the underlying cause. Oral anticoagulation and supplementation with pyridoxine, cyanocobalamine and folate was recommended. Whether therapy with B vitamins and folate can substantially reduce the recurrence of venous thromboembolic disease remains to be established.

Laparoscopic subtotal splenectomy in hereditary spherocytosis

BACKGROUND

Clinical manifestations of hereditary spherocytosis can be controlled by splenectomy. The use of this procedure has been restricted due to concerns regarding exposure of patients to a lifelong risk of overwhelming infections. Subtotal splenectomy, which removes 85-90% of the enlarged spleen, is a logical alternative. In the first cases performed by laparoscopy we have chosen to preserve the upper pole. However, this technique showed some disadvantages, especially concerning the correct intraoperative evaluation of the splenic remnant volume. Therefore, we developed a new variant of the procedure by preserving the lower pole of the spleen.

METHODS

Based on the authors' experience in laparoscopy (176 laparoscopic splenectomies), 10 laparoscopic subtotal splenectomies were performed in patients with hereditary microspherocytosis, preserving either the upper or the lower splenic pole.

RESULTS

Patient age ranged between 5 and 35 years. The mean volume of the remnant spleen was 41.4 cm3. There were no complications, and no transfusions were needed. Follow-up for 1-30 months was available.

CONCLUSIONS

Subtotal splenectomy appears to control hemolysis while maintaining splenic function. The laparoscopic approach is safe and effective and should be considered the procedure of choice in hereditary microspherocytosis. Laparoscopic subtotal splenectomy presents an advantage over open subtotal splenectomy, resulting in decreased blood loss, shorter hospital stay, no conversions, fewer operative and postoperative complications, and excellent remission rates. On the basis of our experience, the preservation of the lower pole of the spleen seems to be a first-line option for the optimal evaluation of the residual splenic mass.

Scanning of beta-globin gene for identification of beta-thalassemia mutation in Romanian population

Beta-thalassemia is uncommon (0.5%) in the Romanian population, but it must be considered in the differential diagnosis of hypochromic anemia. The molecular characterization of beta-thalassemia is absolutely necessary for molecular diagnosis, as well as any genetic epidemiological study in this region. Molecular analyses consist of mutation detection by molecular scanning of beta-globin gene. This gene has 3 exons and 2 introns, involved in beta-thalassemic pathogenesis. Clinical application of DNA analysis on beta-thalassemic chromosomes allowed characterization of 29 persons with different beta-thalassemia mutations among 58 patients with anemia. The experimental strategy was based on sequential PCR amplification of most of the beta-globin gene and running on denaturing gradient gel electrophoresis of amplification products. Definitive characterization of mutations in samples identified with shifted DGGE patterns was performed ARMS-PCR and/or PCR-restriction enzyme analysis methods. Eight different beta-thalassemia alleles were identified, the most common being IVS I-110 (G-A) and cd 39 (C-T). Comparison of overall frequency of mutations in the neighboring countries, shows that these results are in the frame of overall distribution of these mutations in Mediterranean area, especially in Greece and in Bulgaria. Molecular diagnosis is useful for differentiating mild from severe alleles, for genetic counseling, as well as for mutation definition in carriers, identified by hematological analysis necessary for prenatal testing and genetic counseling.