Polymorphisms of uridine glucuronosyltransferase gene and irinotecan toxicity: low dose does not protect from toxicity.

Uridine glucuronosyltransferase (UGT) gene polymorphisms have been linked to irinotecan toxicity. Our purpose was to study the association between UGT1A1*28, UGT1A7*2, and UGT1A7*3 polymorphisms and irinotecan toxicity in Greek patients receiving low-dose weekly irinotecan. Blood samples were collected for 46 patients. DNA was extracted and UGT1A1 promoter and UGT1A7 exon 1 genotyping was carried out. Laboratory tests and physical examination were performed on regular basis for the assessment of toxicity. UGT1A1*28 was significantly correlated with both haematologic and non-haematologic toxicity. Moreover, patients carrying UGT1A7 polymorphisms had significant incidence of toxicity. To conclude, UGT polymorphisms play a role in the toxicity of irinotecan, even if the drug is administered in low doses. The genotyping test may be a useful tool for the management of patients who are going to receive irinotecan.

Contribution of G71R mutation to Gilbert's syndrome phenotype in a Greek patient: A case report.

Gilbert's syndrome is characterized by a benign indirect hyperbilirubinemia. It has often been underestimated and undiagnosed because of its mild symptoms; although it is not as rare as was once believed when its frequency was estimated using data originating from biochemical tests. Based on molecular techniques, the occurrence of Gilbert's syndrome has changed, increasing to 10% in the Caucasian population. This molecular defect was described, by Bosma et al, in 1995, and affects the promoter region of the UGT 1A1 gene. In this case report, our aim is to present a new combination of two molecular defects in a Greek patient with Gilbert's syndrome. A 13-year-old Greek girl was examined for Gilbert's syndrome using molecular techniques, and an uncommon genotype was revealed comprising the rare mutation G71R in trans with A(TA)7TAA motif. The G71R mutation according to the literature, as well as our epidemiological data, is rare in Caucasians, while it is common in Asian populations. This is the first case study in the Greek population to report a new genotype for Gilbert's syndrome manifestation in the Caucasian population.

The impact of the mutations of the HFE gene and of the SLC11A3 gene on iron overload in Greek thalassemia intermedia and beta(s)/beta(thal) anemia patients.

In this study, we evaluated the impact of mutations of the HFE and ferroportin gene on iron overload in thalassemia intermedia and betas/betathal patients. Neither HFE (C282Y and H63D) nor ferroportin(Val162del) mutations were determinants of total body iron status, as assessed by ferritin levels, in either group of patients.

Hemothorax due to extramedullary erythropoietic masses.

We describe a 27-year-old male patient suffering from beta-thalassemia intermedia who presented with a nontraumatic spontaneous hemothorax due to extramedullary hemopoietic foci. In reviewing the literature, four similar reports were found. The details of this unusual entity are discussed.

Decreased expression of membrane alpha4beta1, alpha5beta1 integrins and transferrin receptor on erythroblasts in splenectomized patients with beta-thalassemia intermedia. Parallel assessment of serum soluble transferrin receptors levels.

Dysfunction of cell membrane is a recognized consequence of the pathogenetic process underlying the beta-thalassemia syndromes and it is reasonable to hypothesize that surface structures crucial for the development of erythroid lineage may also be affected. The study included six adult splenectomized patients with beta-thalassemia intermedia. Expression of alpha4beta1 integrin (CD49d/CD29), alpha5beta1 integrin (CD49e/CD29) and transferrin receptor (CD71) on peripheral blood and bone marrow erythroblasts and on erythroid precursors grown in vitro was studied by flow cytometry and immunocytochemistry. Serum soluble transferrin receptor levels (sCD71) were also measured with enzyme-linked immunosorbent assay. In beta-thalassemic patients, significant reduction of CD49d, CD29 and CD71 expression was found in peripheral blood nucleated red cells, compared to patients presenting with erythroblasts in the circulation because of other diseases. Marrow erythroblasts were also deficient for the same molecules against the erythroblasts in iron deficiency anemia. All molecules tested were greatly diminished on erythroid precursors developed in vitro from the patients' cells. Serum sCD71 levels were much higher in thalassemic patients in comparison to both patients with iron deficiency anemia and healthy individuals. The loss of certain integrins and CD71 from erythroid precursors in beta-thalassemia intermedia could be attributed to a generalized membrane dysfunction, perhaps affecting the integrity of their transmembrane domains. The elevation of serum sCD71 levels may be the result of the increased red cell lineage turnover or, alternatively, may indicate increased shedding from the cells to prevent iron overload. In any case, further molecular study of the membrane components is warranted to provide a better understanding of the pathogenetic process in beta-thalassemia syndromes.

Analysis of the A(TA)(n)TAA configuration in the promoter region of the UGT1 A1 gene in Greek patients with thalassemia intermedia and sickle cell disease.

Gilbert's syndrome is characterized by mild unconjugated hyperbilirubinemia. The molecular basis of this syndrome usually concerns an additional dinucleotide insertion (TA) in the A(TA)(n)TAA configuration residing in the promoter region of the UGT1 A1 gene. This configuration may vary in length; the "n" represents the different number of TA repeats. The homozygosity A(TA)(7)TAA/A(TA)(7)TAA is involved in Gilbert's syndrome. In many cases of patients with thalassemia intermedia and sickle cell disease considerable variation in bilirubin levels is observed. In this study we investigated the contribution of the A(TA)(7)TAA/A(TA)(7)TAA genotype in the variable unconjugated serum bilirubin levels in 31 Greek patients with thalassemia intermedia and 27 Greek compound heterozygotes for beta thalassemia and sickle cell anemia. Analysis of the A(TA)(n)TAA configuration in the promoter region of the latter patients showed that those who were carrying the homozygosity A(TA)(7)TAA/A(TA)(7)TAA had higher levels of unconjugated bilirubin. These findings suggest that the coexistence of Gilbert's syndrome in patients with thalassemia intermedia and sickle cell disease may be the cause of the elevated values of unconjugated bilirubin, reducing the possibility of excessive hemolysis in these patients.

Plesiomonas shigelloides sepsis in a thalassemia intermedia patient.

Bacteremia due to Plesiomonas shigelloides was associated with rapidly fulminant septicemia, disseminated intravascular coagulation and massive adrenal hemorrhage in a splenectomized patient suffering from thalassemia intermedia who was treated with hydroxyurea. P. shigelloides was isolated in blood cultures; despite a vigorous combination of antibiotics the patient died after 24 h in the ICU. Lethal sepsis due to P. shigelloides has not previously been reported in Greece.

Amelioration of painful crises in sickle cell disease by venesections.

Sickle cell disease patients who acquire iron deficiency may experience a degree of amelioration from painful crises in terms of frequency, severity, and duration. This observation prompted us to identify the potential utility of iron load reduction in the management of this disease. Thirteen sickle cell patients not ameliorated by conventional treatment entered a weekly venesection protocol. Hematological values and painful crises of all degrees of severity were recorded and compared to those of the last 12 months before venesection for each case separately ("historical controls"). A decrease was noted in the frequency and intensity of several types of painful crises. Reduction of iron load by venesection seems to be a simple, safe, side-effect-free, and efficient way of preventing and ameliorating to a large extent painful crises in sickle cell disease. The biological effects of venesection on other parameters of sickle cell disease remain to be determined.