Hemoglobin E levels in double heterozygotes of hemoglobin E and SEA-type alpha-thalassemia.

Coinheritance of alpha-thalassemia and hemoglobin E (Hb E) is prevalent in Thailand, where the gene frequencies of thalassemia and hemoglobinopathies are high. Hb E carriers with, concomitant inheritance of alpha-thalassemia 1 are known to have a lower level of Hb E. In this study, we reviewed the Hb E levels in Hb E carriers, who either had or did not have Southeast Asian (SEA)-type alpha-thalassemia, in order to seek a Hb E level that may be used as a predictor for concomitant alpha-thalassemia carrier status. The Hb E levels as measured by microcolumn chromatography in 844 Hb E carriers detected during a prenatal screening program for severe thalassemia at Chiang Mai University Hospital were reviewed. Hb E levels ranged from 12.3-35.0% (23.3 +/- 3.1%) in 751 Hb E carriers without SEA-type alpha-thalassemia and from 11.6-32.0% (17.0 +/- 3.7%) in 93 concomitant Hb E and SEA-type alpha-thalassemia carriers. The difference was significant (p < 0.01). However, the absence of SEA-type alpha-thalassemia could not be predicted by the higher Hb E level alone, as 3% of double heterozygotes demonstrated a level of more than 25%. Our study confirms a lower Hb E level in double heterozygotes with Hb E and SEA-type alpha-thalassemia. Nevertheless, the difference does not provide sufficient discriminatory power for the reliable exclusion of alpha-thalassemia status.

Hematological and molecular characterization of beta-thalassemia/Hb Tak compound heterozygote.

We report a case of beta-thalassemia/Hb Tak compound heterozygote. The 7 year-old Thai boy presented with plethora since birth. Hemoglobin electrophoresis showed a major band between Hb A2 and Hb F and absent Hb A. DNA sequencing study demonstrated an AC insertion at the terminal codon of the beta-globin gene. The clinical feature of polycythemia reflected a high oxygen affinity of Hb Tak.

Outcome of intracranial hemorrhage in infants with congenital factor VII deficiency.

The outcome of 8 episodes of intracranial hemorrhage in 7 patients (4 males, 3 females) with congenital factor VII deficiency was evaluated. Their levels of factor VII clotting activity (FVII:C) were less than 1 per cent (n = 3) and ranged from 1.7 to 2.3 per cent (n = 4). The onset varied from the first week (n = 2), first month (n = 3), and at the ages of 6, 11 and 12 months (n = 3). The replacement therapy of 10 ml/kg of fresh frozen plasma (FFP) every 6-12 hours for 5-7 days was given to 6 patients. Only one craniotomy for the removal of hematoma was performed. The seventh patient experienced two episodes of bleeding. First, she received 20 microg/kg of recombinant factor VIIa (rFVIIa) every 6 hours for 4 days (1,200 microg) followed by FFP in one episode. Second, a craniotomy for the removal of a 7 cm diameter hematoma was performed by giving 20 microg/kg of rFVIIa every 6 hours for 12 days (9,600 microg) followed by FFP in another episode. As a result of these treatments, 2 died and 5 survived with sequelae, except for one who received rFVIIa. The sequelae included seizure disorder (n = 1) and hydrocephalus (n = 3). Subsequently, the surviving patients received 15 ml/kg of lyophilized fresh plasma every 3-5 days as prophylactic treatment. In conclusion, rFVIIa in the dose of 20 microg/kg every 6 hours has been shown to be effective in controlling intracranial hemorrhage in patients with congenital factor VII deficiency.