Search PubMed⌕ Search

Biomedical subjects

E A Letsky

Publications and source records attributed to E A Letsky.

At least 37 records · Page 2Linked to original sources
PubMed1991

The effect of intrauterine intravascular blood transfusion on iron metabolism in fetuses with Rh alloimmunization.

Fetal plasma ferritin concentrations were measured in 43 normal fetuses at 18-36 weeks and in 78 blood samples collected before transfusion from 23 fetuses with Rh alloimmunization. Among controls, there was a significant correlation between fetal serum ferritin and gestational age (r = 0.39, P = .009), consistent with an increase in fetal storage of iron during normal pregnancy. In Rh-alloimmunized fetuses, the ferritin concentration was above the reference range in 63% of the samples. Before the first transfusion, the fetal ferritin concentration was increased compared with controls (mean multiples of the mean = 2.6, range 1-26) and showed a negative correlation with fetal hematocrit (r = -0.43, P less than .05), suggesting that the worse the fetal anemia, the higher the iron store. Serial transfusions were associated with further increase in serum ferritin, which correlated primarily with the total volume of blood transfused. Three fetuses had plasma serum ferritin concentrations above 1 mg/L, a level compatible with a diagnosis of iron overload in children. These observations suggest that there is a potential risk of iron overload in Rh-alloimmunized fetuses undergoing intrauterine blood transfusion.

Blood Transfusion, Intrauterine↗
PubMed1990

Continuing controversy in alloimmune thrombocytopenia: fetal hyperimmunoglobulinemia fails to prevent thrombocytopenia.

Two patients with severe alloimmune thrombocytopenia were managed by weekly intrauterine platelet transfusions at 25 to 36 weeks. In one patient high-dose immunoglobulin was also administered weekly to the mother, and high maternal and fetal immunoglobulin levels were achieved. Fetal platelet counts were similar in both patients. The only variable that affected fetal platelet concentration was the posttransfusion platelet count from the previous transfusion.

Blood Transfusion, Intrauterine↗
PubMed1989

Fetal macrocytosis in association with chromosomal abnormalities.

Mean red cell volume (MCV) was determined in 264 fetuses between 15-41 weeks. After exclusion of anemic, hypoxic, and chromosomally abnormal fetuses, the MCV in 208 umbilical venous samples was shown to decrease with gestation (r = 0.64; P less than .001), and a normal range was constructed by linear regression analysis. An elevated MCV was found in both fetuses with triploidy, in four of five with monosomy X, and in four of ten with trisomies 18 or 21. The MCV was similarly raised in four of five fetuses with gross anomalies in whom cytogenetic cultures had failed. Significant correlations were found in chromosomally abnormal fetuses between the elevation in MCV and both the nucleated red cell (r = 0.69; P less than .01) and reticulocyte counts (r = 0.57; P less than .05). There was a similar correlation with nucleated red cells in 16 severely anemic fetuses with Rh disease, 12 of whom had a raised MCV. Elevation in MCV was unrelated to hypoxia. Macrocytosis had a sensitivity of 71% and a specificity of 95% in the second trimester for predicting an abnormal karyotype in nonanemic fetuses (kappa index 0.60). Fetal MCV may provide clinically useful information while one awaits culture results. We suggest that karyotyping be considered in fetuses undergoing blood sampling for other indications in whom the MCV is raised.

Anemia↗
PubMed1988

Consequences of fetomaternal haemorrhage after intrauterine transfusion.

Fetomaternal haemorrhage was studied after 68 consecutive fetal intravascular transfusions performed in 20 patients with Rh isoimmunisation. alpha Fetoprotein concentration was assayed in maternal blood taken before, and immediately after each transfusion and three and 24 hours later. An increase of 50% or more in the concentration in any of the samples after transfusion was considered to indicate fetomaternal haemorrhage. Fetal alpha fetoprotein concentration in blood sampled before transfusion was also assayed and the amount of fetomaternal haemorrhage calculated. Fetomaternal haemorrhage occurred in 21 of 32 patients with an anterior placenta and in six of 36 with a posterior or fundal placenta. The mean estimated volume of haemorrhage was 2.4 ml, which was on average equal to 3.1% of the total fetoplacental blood volume. When the volume of fetomaternal haemorrhage at the first transfusion was greater than 1 ml there was a greater increase in maternal Rh (D) antibody titres and a greater fall in fetal packed cell volume. Sampling of fetal blood should not be routinely done early in patients with Rh isoimmunisation, and intrauterine transfusion should be delayed as long as possible. Sampling sites other than the placental cord insertion reduces the risk of fetomaternal haemorrhage.

Blood Transfusion, Intrauterine↗
PubMed1983

Thalassaemia intermedia in Cyprus: the interaction of alpha and beta thalassaemia.

Restriction endonuclease analysis has been performed on the alpha and beta globin gene clusters of 57 Cypriots homozygous for beta thalassaemia, 30 with the transfusion dependent form of the condition (thalassaemia major) and 27 who are less severely affected (thalassaemia intermedia). There was a significant difference in the incidence of alpha thalassaemia between the two groups: 14/27 of the patients with thalassaemia intermedia also had deletion forms of alpha thalassaemia, while only 4/30 of the patients with thalassaemia major were similarly affected. Thus in Cypriot patients who are homozygous for beta thalassaemia the co-inheritance of alpha thalassaemia is an important factor in determining the clinical course.

Adolescent↗
PubMed1982

Survival and desferrioxamine in thalassaemia major.

A small randomised trial and observation of all patients homozygous for beta-thalassaemia in Britain born in or before 1963 indicated that those patients who had received average weekly doses of more than 4 g of desferrioxamine over the previous few years were less likely to die in the near future than were patients of similar ages who had received less, or no, desferrioxamine.

Adolescent↗
PubMed1978

Prevention of iron loading in transfusion-dependent thalassaemia.

Urinary iron excretion after single intramuscular (i.m.) bolus injections or 12 h subcutaneous (s.c.) infusions of desferrioxamine (D.F.) was determined in sixteen homozygous beta-thalassaemia patients whose ages ranged from 10 months to 23 years. At all ages the s.c. infusions resulted in greater iron loss than identical i.m. doses. With doses of 0.5-1 g of D.F. as s.c. infusions eight out of nine children aged less than 6 years with a total transfusion iron load of less than 10 g excreted sufficient iron to achieve iron balance. These results suggest that iron loading in transfusion-dependent thalassaemics may be preventable by the use of an appropriate chelation regimen started early in life.

Adolescent↗
PubMed1976

Hemolysis following correction of double-outlet right ventricle.

A 41/2-year-old child developed a severe degree of intravascular hemolysis within 24 hours after intraventricular correction of double-outlet right ventricle with a Dacron patch. The child developed jaundice, with a serum bilirubin of 4.3 mg. per cent. The hematocrit value fell from 47 to 25 per cent and the reticulocyte count rose to 22 per cent. The hemolysis diminished after 3 weeks and completely disappeared after 6 weeks. We presume that the hemolysis was due to turbulence caused by a long, curved patch and that its disappearance coincided with the endothelialization of the patch. The child is well 3 years after the operation.

Anemia, Hemolytic↗
PubMed1974

Long-term chelation therapy in thalassaemia major: effect on liver iron concentration, liver histology, and clinical progress.

A prospective trial of continuous chelation therapy in children with homozygous thalassaemia on a high transfusion regimen was started in April 1966. The effect of treatment on iron concentration in the liver and on hepatic histology was examined in 49 biopsy specimens obtained from nine chelator-treated patients and nine control patients between April 1966 and April 1973.Chelation therapy was associated with a significant reduction in liver iron concentration, and by the end of the trial the values for the two groups showed no overlap. A similar difference was seen in the amount of hepatic fibrosis, which showed little or no change in the chelator-treated patients but was progressive in the controls.No major clinical differences were seen, probably because both groups included several older children who were heavily loaded with iron at the start of the trial. Among the younger patients, however, puberty was delayed in four of five controls but in only one of four chelator-treated children. Prepubertal growth rate was significantly greater in the chelator-treated patients than in the controls.

Biopsy↗
PubMed1974

Serum ferritin in children with thalassaemia regularly transfused.

A controlled trial of continuous chelation therapy in regularly transfused children with homozygous beta-thalassaemia has been in progress at the Hospital for Sick Children since April 1966. In the sixth and seventh years of the trial the effect of this treatment on iron overload has been assessed by estimating serum ferritin levels and liver iron concentrations in both chelator-treated and control groups. When compared with non-chelated controls, results of both these estimations were invariably lower in the chelated group. However, all the results in both groups were very high, and fell within the ranges observed in untreated idiopathic haemochromatosis. A close correlation was found between serum ferritin levels and liver iron concentrations in these children, indicating that serum ferritin is a valuable alternative to liver iron concentration in the assessment of visceral iron overload, even when massive tissue siderosis is present.

Blood Transfusion↗