Biomedical subjects

C Breymann

Publications and source records attributed to C Breymann.

28 records · Page 2Linked to original sources

PubMed1998

[Effect of continuous intravenous tocolysis with beta 2-mimetics and magnesium sulfate on erythropoietin level].

14 pregnant women receiving continuous intravenous tocolysis for threatened miscarriage were studied for an effect of beta 2-mimetics on erythropoiesis in humans. After tocolytic therapy for 48 h, the hematokrit fell by 14%; conversely erythropoietin levels rose by 88.7%. Increased erythropoiesis was reflected in increased reticulocyte (and reticulocyte subpopulation) counts. There was a significant correlation between cumulative tocolytic dose and erythropoietin elevation at 48 h. The hypervolemia evidenced by the decreased hematocrit was due to the increased oral fluid intake and fluid retention, and was the presumed main cause of the elevated erythropoietin levels. This effect could enhance understanding of the control of erythropoietin secretion. A similar mechanism may account for the increase in erythropoietin levels in pregnancy.

Adult↗

PubMed1996

Optimal timing of repeated rh-erythropoietin administration improves its effectiveness in stimulating erythropoiesis in healthy volunteers.

We studied the effect of recombinant human erythropoietin (rhEPO) on erythropoiesis when given at different time intervals to healthy adults. 15 volunteers were randomly selected to receive rhEPO (2 x 300 U/kg) and parenteral iron (2 x 200mg) either within a 24 h or 72 h interval. Controls received parenteral iron only. Maximum EPO levels were found 24 h after the first intravenous injection (day 1) with a mean value of 364 and 390 U/l for the rhEPO-treated groups. When second rhEPO administration was after 72 h (group III), volunteers showed significantly higher absolute reticulocyte counts and a higher percentage of young RNA-rich reticulocytes (HFR ratio) over several days compared to those who received rhEPO within a 24 h interval (group II). Both rhEPO-treated groups showed an increase in the mean reticulocyte cell volume. Reticulocyte haemoglobin concentration was inversely correlated with the increasing cell size with a nadir on day 8. Reticulocyte haemoglobin content showed a significant decrease in group II after day 5. Serum ferritin levels showed an inverse pattern to the rate of erythropoiesis. After an initial rise, the serum ferritin decrease was most pronounced in group III. Contrary to previous reports with oral iron supplementation, functional iron deficiency was not seen during rhEPO stimulation, due to parenteral iron administration. Our data suggest that the time has interval between repeated administrations of rhEPO has an important influence on its pharmacodynamics. rhEPO given within an interval of 72 h was more effective in stimulating erythropoiesis than administration within 24 h interval for the same total dose.

Adult↗

PubMed1996

Use of recombinant human erythropoietin in combination with parenteral iron in the treatment of postpartum anaemia.

The authors compared the effect of recombinant human erythropoietin (rhEPO) in combination with iron with that of iron therapy only in the treatment of postpartum anaemia. Ninety patients (30 patients/group) received either rhEPO (300 U kg-1, i.v. or s.c., once) and iron (parenteral and oral), or iron therapy only. Erythropoiesis was assessed by haemoglobin and haematocrit increase, absolute reticulocyte counting and reticulocyte flow cytometry. Ferrokinetics was assessed by serum ferritin, transferrin and transferrin saturation measurements. There was no difference before therapy for baseline haematological values or iron status. Patients with endogenous EPO levels below 145 mU mL-1 had a significant benefit from intravenous rhEPO administration with highest haematocrit and haemoglobin levels 4 and 14 days after therapy. rhEPO-treated groups showed a higher absolute reticulocyte count 1 and 4 days after therapy and an elevated percentage of high fluorescent reticulocytes (HFRs). Parenteral iron therapy caused a significant increase of ferritin and transferrin saturation, while transferrin concentration decreased. Ferritin and transferrin levels were lowest after i.v. administration of rhEPO, 1 and 4 days after therapy. C-reactive protein concentration was highest in patients who underwent caesarean section until the end of the observation period. A single dose of rhEPO in combination with iron was more effective in treating postpartum anaemia than iron therapy only, in patients who had low EPO levels despite peripartal blood loss. Postpartum low endogenous EPO levels might be a consequence of inhibiting inflammatory cytokines that are released after spontaneous or operative deliveries.

Anemia↗

PubMed1995

rhEPO treatment of postpartum anemia.

Postpartum hemorrhage is a continuing problem occurring in 5-10% of all deliveries. Due to recent problems with blood transfusion, heterologous blood is nowadays restricted to life-threatening indications. As a consequence the clinician is faced with many patients suffering from overt symptoms of anemia. We therefore investigated the effect of recombinant human erythropoietin (rhEPO) in combination with adequate iron supplementation as an alternative for blood transfusion in postpartum anemia. In a pilot study we could show that rhEPO can enhance the effect of endogenous erythropoietin on erythropoiesis. These data could be confirmed in a larger randomized trial. In another study we could show that rhEPO given s.c. is as effective as i.v. Measurement of the iron stores, however, demonstrated low values at the end of pregnancy indicating that iron is a limiting factor for erythropoiesis in postpartum anemia. In a next study i.v. iron combined with rhEPO showed a greater increase in Hb compared to i.v. iron alone. The chosen dose of i.v. iron, however, was too small as shown by the low ferritin levels. We concluded from these previous studies that rhEPO enhances endogenous erythropoiesis, but so far the effect was only slight (ca 1 g/dl within 14 days); all treated patients developed overt iron deficiency in terms of low ferritin levels despite oral and i.v. iron supplementation; no major side-effects were seen. A further study in healthy non pregnant volunteers demonstrated an effect on erythropoiesis lasting for 3-4 days after a single dose of 300 U/kg rhEPO.(ABSTRACT TRUNCATED AT 250 WORDS)

Anemia↗

PubMed1995

Recombinant human erythropoietin and parenteral iron in the treatment of pregnancy anemia: a pilot study.

Our aim was to correct severe iron deficiency anemia during pregnancy by using a combination therapy of recombinant human erythropoietin and parenteral iron. Eleven anemic pregnant women were treated once weekly until a hemoglobin value of 11.0 g/dl was reached. Red blood cell production was monitored by reticulocyte flow cytometry and hemoglobin increase. Iron status was assessed by serum ferritin values and transferrin saturation values. 8/11 patients showed an immediate response, noted by a continuous increase of reticulocytes, high fluorescent reticulocyte ratio and hemoglobin levels. Three patients who had lower serum ferritin values, low transferrin saturation and a lower reticulocyte count before treatment showed little response. The combination of rhEPO and parenteral iron is effective in stimulating erythropoiesis and in treating certain pregnancy anemias. This therapy could be an alternative for patients refusing blood transfusions or who are resistant to iron alone. Poor response to the treatment can be due to insufficient iron supplementation during therapy with rhEPO or due to factors that inhibit erythropoiesis during pregnancy, such as undetected infections.

Anemia↗

PubMed1994

rh-erythropoietin stimulates immature reticulocyte release in man.

The pharmacodynamics of single intravenous dosing with recombinant human erthropoietin (rhEPO) was investigated in eight healthy volunteers (150 U/kg, n = 2; 300 U/kg, n = 6) with respect to reticulocyte subdivisions (by fluorescence flow cytometry) and serum ferritin over 6.5 d. The present study shows that bolus rhEPO injection produces an immediate release of high and middle fluorescence (immature) reticulocytes with a high RNA content from the marrow into the circulation, whereas the low fluorescence (more mature) reticulocytes were at first not affected. Serum ferritin decreased markedly within 24 h, reaching a nadir 50% of baseline after 120 h (5 d), with no increase in haemoglobin. Our data suggests that rhEPO triggers premature expulsion of immature reticulocytes from the bone marrow into the circulation independent of its effect in stimulating erythropoiesis and that rhEPO has an effect on serum ferritin concentration which in this dynamic situation is dependent not only on the iron stores.

Bone Marrow↗

PubMed1994

rHuEPO in the treatment of postpartum anemia: subcutaneous versus intravenous administration.

The aim of this study was to determine whether single-shot therapy with recombinant human erythropoietin (rHuEPO) is as effective as divided dosing in postpartum anemia for both subcutaneous and intravenous administration. In a randomized prospective study we treated 95 women with postpartum anemia (Hb < 10 g/dl) within 72 h after delivery with rHuEPO (total dose 300 U/kg body weight) and oral iron supplementation in four treatment groups: group A rHuEPO 150 U/kg s.c. once daily for two consecutive days; group B rHuEPO 150 U/kg i.v. once daily for two consecutive days; group C rHuEPO 300 U/kg s.c. once only; group D rHuEPO 300 U/kg i.v. once only. No significant intergroup differences were found in the mean increase of hemoglobin (P = 0.93 for a difference of 1 g/dl). The mean increase in the single-shot groups was 3 g/dl in 14 days. There was a significant reduction of iron stores in all groups. We conclude that single-shot rHuEPO 300 U/kg body weight corrects anemia just as effectively as divided doses on both intravenous and subcutaneous administration. The overall increase in Hb is only slight but preliminary results indicate that the effect can be enhanced by administrating iron intravenously and by an interval therapy with high-dose rHuEPO.

Adult↗

PubMedDate not supplied

Induction of fetal hemoglobin synthesis with recombinant human erythropoietin in anemic patients with heterozygous beta-thalassemia during pregnancy.

OBJECTIVE: Recombinant human erythropoietin (rhEPO) increases fetal hemoglobin synthesis in nonpregnant thalassaemic patients. We used rhEPO in 4 pregnant patients with heterozygous beta-thalassemia and anemia to study its effect on erythropoiesis, F cell production, and HbF synthesis. METHODS: Patients were treated with a combination therapy of rhEPO and iron. The effect on HbF synthesis was assessed by the percentage of F reticulocytes, F cells, and total HbF, erythropietis by reticulocyte count, and hemoglobin measurements and iron status by ferritin levels, transferrin saturation, and percentage of hypochromic red cells. RESULTS: RhEPO caused an increase of F reticulocytes (1.5 to 10.5 fold), F cells (5.0 to 7.7 fold), and HbF (1.4 to 2.2 fold). All patients showed an increase of young, immature reticulocytes and had elevated reticulocytes at the end of therapy. Hemoglobin increased with a range from 0.3 to 1.5 g/dL. Transferrin saturation and ferritin levels were normal at the end of the study. There was an increase of the percentage of hypochromic red cells, indicating functional iron deficiency after rhEPO administration despite supplemental iron. CONCLUSIONS: RhEPO stimulates both HbF synthesis and erythropoiesis in pregnant patients with heterozygous beta-thalassemia and anemia. Since it is known that high HbF levels ameliorate thalassemia symptoms in nonpregnant patients, use of rhEPO for the treatment of severe anemia in thalassaemic patients during pregnancy might be further evaluated.

Adult↗

PubMedDate not supplied

[Two-stage delivery after spontaneous rupture of fetal membranes and delayed abortion of the first twin in conservative management].

INTRODUCTION: 1-2% of all twin pregnancies are complicated by premature contractions, leading to premature rupture of membranes before 26 weeks of pregnancy. In this situation, a decision is required to either actively induce premature delivery or to initiate expectant management. Maternal and fetal risks regarding perinatal mortality and morbidity and the benefits of pregnancy prolongation have to be weighted against each other. CASE REPORT: We present delayed deliveries of two I-Parae with dichorionic twin pregnancies, achieved by in vitro fertilisation. In both cases, spontaneous membrane rupture and miscarriage of the leading fetus occurred prior to 20 gestational weeks. As signs of infection were missing initially, we adopted a conservative, expectant management. In both cases, the pregnancies could be prolonged to more than 30 weeks' gestation. DISCUSSION: In the absence of additional risk factors, expectant, conservative management of multiple pregnancies after loss of one fetus can lead to pregnancy prolongation of 91 and 96 days, respectively. The gained gestational age of the remaining fetus and the healthy mother-child pairs are discussed under perinatal, economical and psychological aspects.

Abortion, Spontaneous↗

PubMedDate not supplied

Unexplained elevated serum hCG is associated with raised amniotic fluid erythropoietin levels in second-trimester pregnancies.

OBJECTIVE: This study was designed to investigate the association between the concentrations of maternal serum hCG and amniotic fluid erythropoietin during the second trimester of pregnancy. METHODS: In a prospective case-control study, 42 consecutive singleton pregnancies showing unexplained elevated serum hCG concentrations (>2.0 multiples of the median, MoM) in Down's syndrome screening and 27 control pregnant women undergoing midtrimester amniocentesis because of a previous cytogenetic abnormality were studied. RESULTS: The mean amniotic fluid erythropoietin concentration in the study group was 1.8 (range 0.61-8.7) MoM, whereas it was 1.1 (range 0.71-3. 96) MoM in the controls (p = 0.035). A significantly increasing relationship (p < 0.05) was found between the concentrations of maternal serum hCG and amniotic fluid erythropoietin. CONCLUSIONS: The results of the current study revealed in vivo the association between elevated hCG and amniotic fluid erythropoietin levels which, in turn, supports the concept of early placental damage. The underlying pathology seems to be sufficient to cause an erythroblastic response.

Adult↗