HLA class I antibodies in thalassemic patients.

This study was undertaken to demonstrate the prevalence of HLA class I antibodies among 62 polytransfused patients. The diagnosis included beta-thalassemia major, beta-thalassemia/Hb E disease and severe Hb H disease. Their ages ranged from 1 year to 23 years with the mean age of 10.7 years. The number of packed red cell transfusions ranged from 3 to 235 with the mean of 60 episodes per patient. The standard microlymphocytotoxicity test was performed using 50 panels of lymphocytes which specifically identified the majority of HLA class I antibodies. 31/62 cases (50%) were positive for HLA class I antibodies. The detection of single or multiple antibodies depended upon the number of blood transfusions and the patients' ages. These antibodies were induced by the leukocytes present in the transfused packed red cells. Therefore, leukocyte-reduced packed red cells prepared by either additional inverted centrifrugation or leukocyte filter is suggested for the routine blood bank service.

Prenatal diagnosis of Hb Bart's hydrops fetalis by PCR technique: Pramongkutklao experience.

Hb Bart's hydrops fetalis is very common in Southeast Asia, especially in Thailand. As the mother of such an infant may suffer from toxemia of pregnancy, ante- or post-partum hemorrhage as well as the psychological burden for carrying a nonviable fetus to term, so prenatal diagnosis is indicated and the family should be given the choice of early termination of the pregnancy. Seven high risk pregnancies with Hb Bart's hydrops fetalis (homozygous alpha-thalassemia 1) were studied. Amniocentesis was done at 16-33 weeks of gestation. DNA analysis was performed by polymerase chain reaction (PCR) using 2 techniques, 1) three nucleotide primers and 2) four nucleotide primers. After either therapeutic abortion or birth, heart blood or cord blood was drawn to confirm the diagnosis by Hb electrophoresis and DNA analysis. Of 7 high risk fetuses, 3 were recognized as Hb Bart's hydrops fetalis, 2 showed the alpha-thal 1 trait, 1 showed alpha-thal 2 trait and 1 was a normal fetus. The technique was entirely suitable for prenatal diagnosis of Hb Bart's hydrops fetalis. This technique was a rapid, simple non-radioactive method, less expensive and available in most PCR laboratories.

Clinical phenotypes and genotypes diagnosis of thalassemia in children.

Thalassemia is a relatively common hemolytic anemia in Southeast Asia. Alpha and beta thalassemia, hemoglobin (Hb) E, and Hb Constant Spring (CS) are prevalent in Thailand. Different gene combinations lead to over 60 thalassemic syndromes. One hundred and forty-nine thalassemia families were retrospectively studied. They were 4 homozygous beta-thalassemia (beta-thal/ beta-thal), 79 beta-thal/Hb E, 22 Hb H disease, 32 Hb with Hb CS, and 6 AE Bart's disease. The first clinical manifestation and hematologic data including hemoglobin electrophoresis were analysed. Most homozygous beta-thalassemia and beta-thal/Hb E presented with anemia (100% vs 81%), hepatomegaly (40% vs 21%), and splenomegaly (20% vs 27%). In Hb H disease and Hb H with Hb CS, the clinical findings were anemia (74% vs 79%), hepatomegaly (9% vs 8%), splenomegaly (9% vs 13%), jaundice (24% vs 13%), and fever (18% vs 25%). The 317 hematologic data and hemoglobin types of the patients, their parents and relative were also analyzed. These findings can be used as reference values for childhood thalassemia and heterozygous states.

High transfusion in children with beta-thalassemia/Hb E: clinical and laboratory assessment of 18 cases.

Between 1990-1992, 18 patients with beta-thalassemia/Hb E age between 2-13 years (mean 7.4 +/- 3 years) were examined. Three patients were splenectomized and the rest were nonsplenectomized. They were divided into 3 groups. Group A:5 nonsplenectomized and 3 splenectomized patients had high transfusion rates with subcutaneous desferrioxamine injections. Five patients in group B received only high transfusion whereas in 5 patients in group C the levels pretransfusion Hb were maintained between 6-7 g/dl. The mean blood consumption in the nonsplenectomized groups were 220 +/- 25.3, 221 +/- 59 and 175.4 +/- 45.4 ml/kg/year in groups A, B and C, respectively. In group A, the mean blood requirement was 40% higher in the nonsplenectomized group. In the high transfusion regimen the spleen size did not increase and serum aspartate aminotransferase showed a striking fall in the majority of cases. The absolute increases in serum ferritin were 843.2 +/- 395, 861 +/- 252 and 1,262 +/- 440 ng/ml in groups A, B and C, respectively. These data demonstrated that high transfusion with desferrioxamine injection could improve the clinical well being of the patients.

Autoimmune haemolytic anemia in children: A review of 17 cases.

Seventeen children with autoimmune haemolytic anaemia (AIHA) seen at the Department of Paediatrics, Siriraj Hospital during 1977 to 1986 were analysed. The patients were devided into 2 groups, acute and chronic types, according to their response to treatment. In acute type (3 cases) the disease occured within the first year of life, with abrupt onset and severe clinical symptoms but dramatic response to prednisolone. In chronic type (14 cases), the disease appeared mostly at 9-11 years of age, associated with underlying diseases such as systemic lupus erythematosus, thalassaemia or Hodgkin’s disease and poorly responded to prednisolone. Two patients died, from septicaemia in one case and from the uncontrolled underlying disease in another case.