טלזמיה מיינור

אני אם לפעוט בן שנה ועשרה חודשים. לאחרונה נתגלתה אצלו טלזמיה מיינור. ברצוני לקרוא חומר נוסף על מחלה זו ולהבין מכם משמעותה. בברכה ותודה מירה חביב טבריה

שלום מירב ראשית ארגיע אותך ואומר שתלסמיה מינור מפריעה אך במעט (אם בכלל) והחשיבות העיקרית היא בידיעה שהיא קיימת (כאשרי יינשא ב"ה וירצה להביא ילדים לעולם, צריך יהיה לוודא שלא יוולדו ילדים עם תלסמיה מייג'ור). שנית, בגלל קצב הייצור ברה של דם אצל חולי תלסמיה צריך לוודא שיש להם מספיק חומרי גלם - בעיקר הכוונה לחומצה פולית שמומלץ להוסיף בכדורים או בצורה אחרת. כתבתי הרבה בפורום לגבי תלסמיה מינור. מצרף כאן קישורים עיקריים: http://www.doctors.co.il/forums/read.php?f=81&i=1223&t=1163 http://www.doctors.co.il/forums/read.php?f=81&i=1470&t=1455 http://www.hematology.org/education/hema99/chandy.pdf http://www.doctors.co.il/forums/read.php?f=81&i=1560&t=1551 http://www.doctors.co.il/forums/read.php?f=81&i=1570&t=1551 http://www.doctors.co.il/forums/read.php?f=81&i=1768&t=1737 http://www.doctors.co.il/forums/read.php?f=81&i=2475&t=2373 ועוד משהו שלקוח מהספר של חברת מרק להלן הקישור והקטע הרלבנטי: http://www.merck.com/pubs/mmanual/section11/chapter127/127d.htm THALASSEMIAS (Mediterranean Anemia; Hereditary Leptocytosis; Thalassemia Major and Minor) A group of chronic, inherited, microcytic anemias characterized by defective Hb synthesis and ineffective erythropoiesis, particularly common in persons of Mediterranean, African, and Southeast Asian ancestry. Etiology and Pathogenesis Thalassemia is among the most common inherited hemolytic disorders. It results from unbalanced Hb synthesis caused by decreased production of at least one globin polypeptide chain (, , , ). -Thalassemia results from decreased production of -polypeptide chains. The disease is autosomal dominant: Heterozygotes are carriers and have asymptomatic mild to moderate microcytic anemia (thalassemia minor); the typical symptoms occur in homozygotes (thalassemia major). -Thalassemia, which results from decreased production of -polypeptide chains, has a more complex inheritance pattern, because genetic control of -chain synthesis involves two pairs of structural genes. Heterozygotes for a single gene defect (-thalassemia-2 [silent]) are usually free of clinical abnormalities. Heterozygotes for a double gene defect or homozygotes for a single gene defect (-thalassemia-1 [trait]) tend to manifest a clinical picture similar to heterozygotes for -thalassemia. Inheritance of both a single gene defect and a double gene defect more severely impairs -chain production. -Chain deficiency results in the formation of tetramers of excess chains (Hb H) or, in infancy, chains (Bart's Hb). Homozygosity for the double-gene defect is lethal because Hb that lacks chains does not transport O2. In blacks, the gene frequency for -thalassemia is about 25%, and the phenotypic (clinical) expression occurs in 10%. Symptoms and Signs Clinical features of thalassemias are similar but vary in severity. -Thalassemia minor is clinically asymptomatic. -Thalassemia major (Cooley's anemia) presents with symptoms of severe anemia, markedly expanded marrow space, and transfusional and absorptive Fe overload. Patients are jaundiced, and leg ulcers and cholelithiasis occur (as in sickle cell anemia). Splenomegaly is common, and the spleen may be huge. If splenic sequestration develops, the survival time of transfused normal RBCs is shortened. Bone marrow hyperactivity causes thickening of the cranial bones and malar eminences. Long bone involvement makes pathologic fractures common. Growth rates are impaired, and puberty may be significantly delayed or absent. Fe deposits in heart muscle may cause dysfunction and heart failure. Hepatic siderosis is typical, leading to functional impairment and cirrhosis. -Thalassemia-1 (trait) has a similar presentation to -thalassemia minor. Patients with Hb H disease often have symptomatic hemolytic anemia and splenomegaly. Laboratory Findings Table 127-7 lists characteristics of the thalassemias. Serum bilirubin, serum Fe, and serum ferritin levels are increased. Bone marrow reveals marked erythroid hyperplasia. In - or -thalassemia minor, mild to moderate microcytic anemia is usual. Serum Fe and serum ferritin determinations will help rule out Fe deficiency. In -thalassemia major, anemia is severe, often with Hb 3%. The percentages of Hb F and Hb A2 are generally normal in -thalassemias, and the diagnosis often is one of exclusion of other causes of microcytic anemia. Hb H disease can be diagnosed by demonstrating the fast-migrating Hb H or Bart's fractions on Hb electrophoresis. The specific molecular defect can be characterized but does not alter the clinical approach. Recombinant DNA approaches of gene mapping (particularly the polymerase chain reaction) have become standard for prenatal diagnosis and genetic counseling. In -thalassemia major, x-ray findings are characteristic of chronic marrow hyperactivity. The cortices of the skull and the long bones are thinned, and the marrow space is widened. The diploic spaces in the skull may be accentuated, with the trabeculae having a sun-ray appearance. In the long bones, areas of osteoporosis may occur. The vertebral bodies and the skull may have a granular or ground-glass appearance. The phalanges may lose their normal shape and appear rectangular or biconvex. Prognosis and Treatment The outlook varies. Life expectancy is normal for persons with -thalassemia minor. Some patients with -thalassemia major live to puberty or beyond. - and -Thalassemia minor require no treatment. Children with -thalassemia major should receive as few transfusions as possible because Fe overload can result. However, suppression of abnormal hemopoiesis by chronic RBC hypertransfusion may be valuable in severely affected patients; to prevent or delay hemochromatosis, excess (transfusional) Fe must be removed (eg, via chronic Fe-chelation therapy). Transfusing relatively younger fractions of RBCs appears to be advantageous in decreasing the rate of Fe overload. Splenectomy may help decrease transfusion requirements for patients with splenomegaly when superimposed hemolysis occurs in the spleen. Allogeneic bone marrow transplantation has been successful in the small numbers of patients who have received it