RESUMO
Hemoglobin (Hb) Agrinio is a rare non-deletional a-globin mutation observed almost exclusively in Greek, Spanish or other Mediterranean families. The clinical manifestations of a carrier of a single Hb Agrinio mutation (single heterozygosity) depend on the concomitant presence or absence of other mutations or variants in the beta, alpha or other modifying genes. We present a Greek patient harboring a Hb Agrinio variant plus the - -Med alpha deletional allele, having an infrequent severe form of alpha thalassemia, in contrast to the typical alpha thalassemic patient and requiring regular red blood cell (RBC) transfusions and chelation treatment. We also provide a concise literature review regarding alpha thalassemic hemoglobin variants and their molecular and clinical combinations. A phase 2, double-blind, randomized, placebo-controlled, multicenter clinical trial to determine the efficacy and safety of luspatercept (BMS-986346/ACE-536) for the treatment of anemia in adults with alpha thalassemia with the participation of our center is currently recruiting patients (NCT05664737).
RESUMO
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.
Assuntos
Hemoglobinopatias , Talassemia alfa , Talassemia beta , Humanos , Relevância Clínica , Grécia , Genótipo , Hemoglobinopatias/genética , Fenótipo , Mutação , Talassemia beta/epidemiologia , Talassemia beta/genética , Talassemia alfa/epidemiologia , Talassemia alfa/genética , alfa-Globinas/genética , Progressão da DoençaRESUMO
Hemophagocytic lymphohistiocytosis (HLH), or hemophagocytic syndrome (HS) is a severe syndrome involving an extreme participation of the immune system, resulting in a cascade of cytokines, hyperinflammation and extensive hemophagocytosis in the bone marrow (BM) and affecting the peripheral blood (PB) lineages. Fever, splenomegaly, hypertriglyceridemia, hypofibrinogenemia, and hyperferritinemia are often encountered in this disease. The syndrome can be seen in all ages and it is either primary due to genetic defects or secondary because of malignancies, immune deficiencies, rheumatic diseases, and infections. Bacteria, viruses, protozoa, and fungi are often implicated. Visceral leishmaniasis (VL) is among the infectious causes of HLH. We describe a patient with a successful treatment of HLH after the initiation of liposomal amphotericin B, due to VL, even though there was a delay in diagnosing the leishmaniasis. The exact precipitating pathophysiological events triggering HLH remain unknown and provide their clear impact for future research. An instructive, critical review of the literature related to the presented case is provided. Distinguishing secondary HS from primary HS is essential for the application of suitable treatment. Improper use of corticosteroids could cover up an underlying possible malignancy or infection and delay the initiation of the etiologic therapeutic strategy.