The problem of comparative analysis of birth prevalence of congenital cardiovascular malformations.

A number of published papers have dealt with the comparison of birth prevalences of congenital cardiovascular malformation (CCVMs). The feasibility of meaningful intercountry comparison was explored during the visiting fellowships to Dr Andrew Czeizel of Charlotte Ferencz and Dr Francine Lys. Data from three Hungarian studies, one USA and one Belgian study are presented here for selected CCVMs. Differential perinatal and diagnostic circumstances which lead to possible causes of bias involve four main domains: study population, ascertainment of cases, categorization of CCVMs and diagnostic definitions. Unique features are highlighted as a descriptive framework which will promote the comparability of epidemiologic data from various regions.

Subclassification of acute lymphoblastic leukaemia in children: analysis of the reproducibility of morphological criteria and prognostic implications.

Stained smears of aspirated bone marrow obtained at time of diagnosis from 223 children with acute leukaemia were reviewed independently by three observers in a double-blind fashion in order to assess the reproducibility and clinical significance of the French-American-British Cooperative Group Classification. In 170 cases of acute lymphoblastic leukaemia (ALL), triple agreement of 69.4% was reached in the subclassification into L1, L2, and L3 types. The closest degree of agreement between two observers was 86.8%. In children with blasts classified as L1, 57 OF 61 patients (93.4%) remained in haematological remission after 12 months, as compared with 14 of 20 (70%) in children whose blasts were typed as L2 morphology, a difference which was statistically significant (P less than 0.05). There was no difference when these groups were compared after 24 or 36 months. Children older than 7 years had an increased incidence of L2 type (P less than 0.05). We conclude that although there may be significant variation in individual interpretations of the criteria utilized for classification, blast morphology may nevertheless be a useful prognostic factor.

Sickle cell syndromes. I. Hemoglobin SC-alpha-thalassemia.

Hematologic and globin synthesis studies were performed in a black American family in which the genes for alpha-thalassemia and hemoglobins (Hb) S and C were segregating. The following distribution of these abnormalities was found: father, sickle cell trait + alpha-thalassemia; mother, HbC trait + alpha-thalassemia, propositus, HbSC + alpha-thalassemia; older sibling, alpha-thalassemia trait; and younger sibling, hemoglobin H disease. The child with HbSC-alpha-thalassemia demonstrated more severe anemia and a more hemolytic picture than is typical of HbSC disease. Her erythrocytes exhibited decreased osmotic fragility in comparison with HbSC erythrocytes, but had an indistinguishable oxygen equilibrium curve and 2, 3-diphosphoglycerate (2, 3-DPG) level. Erythrocyte sickling in the patient, however, was significantly reduced, with less than 35% sickle forms observed at nearly complete oxygen desaturation. The sibling with hemoglobin H disease exhibited 26% Bart's (gamma4) hemoglobin at birth, a level comparable with that seen in infants with HbH disease in Far Eastern populations. At age 5 months typical findings of mild hemoglobin H disease appeared, with HbH making up 6.5% of the total hemoglobin.

Evaluation of Fagara zanthoxyloides root extract in sickle cell anemia blood in vitro.

An aqueous extract was prepared from roots of Fagara zanthoxyloides and examined for evidence of an antisickling effect in vitro. Addition of 25 mg/ml of the extract to fresh blood samples from sickle anemia subjects produced no change in the blood oxygen dissociation curves, and approximately equal percentages of sickled cells were observed at comparable oxygen saturation levels in the presence or absence of the extract. These observations fail to confirm previous reports describing an antisickling effect of root extracts of Fagara zanthoxyloides.