Gene/Protein Disease Symptom Drug Enzyme Compound
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Query: UMLS:C0002871 (anemia)
 52,094 document(s) hit in 31,850,051 MEDLINE articles (0.00 seconds)

A 40-year-old woman with acute myeloid leukemia in first remission developed pure red cell aplasia after a T cell-depleted ABO-incompatible bone marrow transplant from her HLA-identical sister. She remained transfusion-dependent for 11 months despite conversion of the ABO blood group to donor type, and titers of anti-donor isohemagglutinin being undetectable. Treatment with erythropoietin resulted in rapid improvement of the anemia with no further need for transfusions up to 21 months post-transplant. This case suggests that erythropoietin may provide effective therapy for pure red cell aplasia after ABO-incompatible bone marrow transplantation without the additional risks of further immunosuppression.
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PMID:Successful treatment of pure red cell aplasia after major ABO-incompatible T cell-depleted bone marrow transplantation with erythropoietin. 946 87

This review has two objects: a brief recapitulation of the biological background of erythropoietin (EPO), and a review of its clinical utilization in hematology. EPO, both in its naturally occurring and recombinant form (rH-EPO), is a single chain glycoprotein with an approximate molecular weight of 30.000 to 34.000 kD. Its heavy glycosilation is essential for its activity in vivo, since asialoEPO is readily cleared by the heptic asialoglycoprotein receptor. This impedes the recombinant molecule's synthesis in biologic cultures other than mammalian cells (Chinese hamster's ovary cells), and inevitably increases costs. If in vitro glycosilation of E. coli-derived rH-EPO could be achieved, the clinical utilization of the product would be considerably enhanced, most especially when very high doses are necessary, as discussed later. There is no antigenic diversity between natural and recombinant EPO, so that out of the enormous clinical experience only one single case of immunization has been recorded. Almost paradoxically there are however three published cases of pure red cell aplasia (PRCA) caused by immunization against autologous EPO. It is now established that in adults EPO is synthetized in renal peritubular interstitial cells, although some residual activity remains in the liver. Hypoxia results in a rapid induction of EPO expression, although the role of the oxygen sensor system is still debated. Cellular targets are notoriously erythroid progenitors and precursors (BFU-E, CFU-E, early and intermediate erythroblasts). The global erythropoietic activity resulted in various effects (proliferation, differentiation, survival), but most probably each single effect is integrated with and complementary of the others. The utilization of rH-EPO in hematologic diseases came much later than its dramatic success in renal anemia. A variety of tools useful for assessing the possible beneficial effects of rH-EPO in clinical hematology has been proposed, among which a low level of endogenous EPO is a good predictor for therapeutic success. 'Hemopathic' anemia can be subdivided into three categories: patients with normal erythropoiesis due to inadequate EPO production (anemia of prematurity), patients with depressed but nonclonal erythropoiesis (chemotherapy, lymphoid malignancies such as multiple myeloma-MM and chronic lymphatic leukemia-CCL) and patients with at least partially clonal anemia, such as paroxysmal nocturnal hemoglobinuria (PNH), hemoglobinopaties, myelodysplastic syndromes (MDS) and others. Results in the first category of patients are, as expected, prompt and satisfactory with physiologic doses. Although therapeutic strategy for MM is moving fast to curative intents, the utilization of rH-EPO is indicated for the control of anemia in conservatively-treated patients. In the third category the most important and controversial area is MDS. Significant erythropoietic results are generally obtained in about 20% of patients; however, the association with G-CSF has considerably enhanced the response rate. In the field of bone marrow transplantation there is an inadequate production of endogenous EPO in the allogeneic setting, and randomized studies have shown the benefits of rH-EPO in this situation. However, the most important results have been obtained in post-major-ABO incompatible PRCA, when the removal of the recipient's isohemagglutinins does not resolve the anemia. High and very high doses of rH-EPO (even over 500 UI/kg/day for 2-4 weeks) may resolve this occasionally quite refractory condition. Although extremely expensive, this treatment may be life-saving when an otherwise successful allogeneic transplant is at the risk of failure because of this relatively uncommon but severe immunohematologic complication.
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PMID:[Erythropoietin: biochemical characteristics, biologic effects, indications and results of use in hematology]. 948 78

Aregeneratoric anemia (AA) occurs rarely after ABO-incompatible allogeneic peripheral blood stem cell transplantation (alloPBSCT), and its management is generally difficult. Here, we present a 31-year-old white man with myelodysplastic syndrome who developed AA after receiving stem cells from his human leukocyte antigen (HLA) identical, but ABO-incompatible sibling. Because his anti-A antibody titers were high, therapy with conventional doses of erythropoietin and prednisolone failed to treat the AA. Following 8 cycles of plasma exchange and higher doses of erythropoietin and prednisolone as well as danazol administration, anti-A titers decreased, and his anemia improved significantly. In conclusion, to treat and obtain a low titer of antibodies in a patient with AA following an ABO-incompatible alloPBSCT, higher doses of erythopoietin and corticosteroids associated with plasma exchange have to be used.
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PMID:Treatment of aregeneratoric anemia following an ABO-incompatible allogeneic peripheral blood stem cell transplantation: a case report. 1042 29

We evaluated the use of a semi-automated processing technique to salvage red blood cells from pediatric bone marrow donors to minimize the risk of severe anemia following bone marrow harvest and ABO incompatibility in the recipient. Sixty healthy, HLA-matched, pediatric donors of bone marrow hematopoietic cells with a median age 8.0 years (2-19) were studied. Thirteen of the donor-recipient pairs were ABO incompatible. There were 60 recipients with a median age of 8.6 years (2 months to 20.8 years). Bone marrow was harvested under general anesthesia, filtered in the operating room and then transferred to the stem cell laboratory for processing. Samples were obtained for cell count, CD34+ quantification, colony assay, viability, and bacteriologic cultures before and after processing. The cells were processed in a semi-automated closed system (Stericel, Terumo) by density gradient separation with Ficoll-Hypaque and then washed. Two aliquots were obtained: one containing the mononuclear cell layer to be infused to the recipient and the other the washed red cells to be infused to the donor. The median volume harvested was 608 +/- 40.42 ml (278-1409), while the final volume infused was 174 +/- 10.75 ml (30.2-380) P < 0.0001, representing a decrease of 72% of the volume infused. The nucleated cell count harvested was 1.6 x 10(10) +/- 0.1 (0.56-3.2), while the count infused was 6.9 x 10(9) +/- 0.1 (0.12-5.4) P < 0.0001. The median mononuclear cell count (MNC) per kg harvested was 0.67 x 10(8) +/- 0.05 (0.18-2.0) vs an infused cell number of 1.3 x 10(8) MNC/kg +/- 0.1 (0.6-33.6) P < 0. 0001. The CD34+ cells harvested were 2.8 x 10(6)/kg +/- 0.1 (0.25-10.2) vs an infused number of 6.0 x 10(6)/kg +/- 0.5 (0.84-31.0) P < 0.0001. The viability before and after processing was 99%. Red cell salvage performed in a semi-automated closed system is safe and reduces the risk of post-bone marrow harvest anemia in pediatric donors, decreases the volume infused into the donor and enriches the mononuclear and CD34+ cell population, without affecting hematopoietic reconstitution.
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PMID:Red cell salvage and reinfusion in pediatric bone marrow donors. 1046 27

Two siblings born 6 years apart presented with similar findings of hepatosplenomegaly, dermal hematopoiesis, hemoglobinuria, and increased platelet consumption, but only moderate anemia and normal serum bilirubin. ABO incompatibility was identified, and other causes were excluded. A review of the current understanding of mechanisms that promote and prevent antibody-mediated hemolysis in the fetus is reviewed. Due to the low ratio of observed to expected significant clinical events among ABO incompatible mother-infant pairs, and the multiplicity of mechanisms that diminish hemolysis, we speculate that severe ABO hemolytic disease of the newborn occurs when there is a specific failure in one of these preventive mechanisms.
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PMID:ABO hemolytic disease of the newborn: a unique constellation of findings in siblings and review of protective mechanisms in the fetal-maternal system. 1077 97

Therapeutic erythrocytapheresis (TEA) has been used in different diseases such as polycythemia vera (PV), secondary erythrocytosis or hemochromatosis as a process of the less cumbersome but more expensive phlebotomy. TEA is preferred in emergency conditions such as thrombocytosis or in conditions such as porphyria cutanea tarda (PCT) or erythropoietic porphyria when plasma exchange (PEX) is often combined with TEA to reduce extracellular levels of uroporphyrin which contribute to plasma hyperviscosity. TEA is often combined with drug therapy that varies from etoposide in PV to EPO and desferoxamine which are used to mobilize and reduce iron stores in hemochromatosis. Benefits from this combination may be more long lasting than expected. Nonetheless for TEA, there is no standard protocol and, clinical experience with this therapy remains highly anecdotal. Therapeutic red cell-exchange (TREX) has been used with much interest over the years, starting with the management of hemolytic disease of the newborn and later used to correct severe anemia in thalassemia patients thereby preventing iron overload. It has also been used for the management of complications of sickle cell disease such as priapism, chest syndrome, stroke, retinal, bone, splenic and hepatic infarction or in preparation for surgery by reducing HbS to less than 30%. Automated apheresis has also favored the use of TREX in conditions such as paroxysmal nocturnal hemoglobinuria and aniline poisoning, arsenic poisoning, Na chlorate intoxications and CO intoxications, hemoglobinopathies, autoimmune hemolytic anemia, reactions due to ABO incompatibility, in preparation for ABO incompatible bone marrow transplantation or for preventing anti-D immunization after the transfusion of D(+) cells to D(-) recipients. Another field of application has been in the emergency management of intraerythrocytic parasite infections such as malaria and babesiosis. Application of TREX may be wide but its real use remains limited. In our personal experience, in 16 years, only 167 TREX procedures have been carried out in a total of 13,747 therapeutic procedures. This represents only 1.21% of the total.
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PMID:Clinical application of therapeutic erythrocytapheresis (TEA). 1083 21

Red blood cell (RBC) transfusions are frequently used in the management of patients with chronic renal failure (CRF) undergoing hemodialysis for dialysis-related anaemia. Consequently, they are subject to all hazards associated with repeated transfusions, such as red cell alloimmunization. A retrospective study was performed to estimate the frequency of alloimmunization against red cell antigens in multitransfused CRF patients. A total of 81 patients (67 males & 14 females) with CRF were studied who received a mean of 8.5 units of RBC matched for ABO & Rh(D) antigens only. Using standard techniques (indirect antiglobulin test, enzyme, polyethylene glycol, and low ionic strength solution), we observed a RBC alloimmunization rate of 9.8% (8/81). Nine alloantibodies were detected in 8 patients, and most (88%) involved antigens in the Rhesus & Kell systems. No correlation was observed with the alloantibody formation & number of units transfused. The calculated risk of 1.3% observed in the present study, suggests that renal failure patients are not at a higher risk of red cell alloimmunization than the general population.
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PMID:Red cell alloimmunization in multi-transfused chronic renal failure patients undergoing hemodialysis. 1086 87

HIV transmission is the greatest single risk of blood transfusion today. The World Health Organization estimated in late 1900 that 8-10 million persons worldwide were HIV seropositive. In Africa, 10% of adult and 25% of early childhood HIV infections are believed to be caused by contaminated transfusions. 90% of patients transfused with contaminated blood will become infected. The other serious infectious risks of transfusion are hepatitis B, malaria, and syphilis. Accidents and complications of transfusion can be avoided if transfusions are limited to absolute indications, clinical examinations of donors are thorough, the blood group is reliably determined, and testing of blood for HIV is reliably conducted. Transfusions not formally indicated are now formally contraindicated. The vital risk if the patient is not transfused must be assessed before the transfusion is done, as should the risk of transmitting infection through the transfusion. When emergencies occur in isolated areas, the donor is often a family member or person accompanying the patient. The blood of the donor as well as of the patient must be typed. The medical history and clinical examination of the donor to exclude contraindications must be thorough. The physical contraindications to blood donation are infectious disorders and especially AIDS, a history of untreated syphilis or jaundice, and recent malaria. Blood should never be donated by persons with fever, jaundice, cutaneous lesions suggesting syphilis or AIDS, clinical anemia, or cardiac insufficiency. Pregnant women and children under 15 should not donate blood. Aseptic conditions must be maintained during all handling of the blood. ABO and rhesus grouping and testing for HIV infection must be done in all cases. ELISA tests are most often used for blood screening, but the rapid tests developed a few years ago are equally reliable and more suited to isolated medical facilities or those that perform few transfusions. Because the tests give false positive results in a significant proportion of cases, they should be repeated before a positive result is reported. The results of an HIV test, whether positive or negative, should only be reported to the donor if information on the consequences of a positive test has been provided and consent to the test has been obtained, the screening test results have been confirmed by a diagnostic test, and the seropositive individual can receive medical follow-up and counselling. Prevention of syphilis transmission can be achieved by limitation of indications for transfusion, selection of low risk donors, clinical examination of donors, use of blood stored for 72 hours at 4 degrees celsius or lower, use of screening tests, and prophylactic administration of antibiotics. Clinical examination and a careful medical history are the main tools for preventing hepatitis B transmission. Systematic prophylaxis against malaria following national protocols is recommended.
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PMID:[Transfusion practice in isolated areas: prevention of HIV transmission]. 1228 4

Minor blood group hemolytic disease is extremely rare, since the overall potency of minor blood groups in inducing antibodies is significantly lower when compared with that of Rh (D) antigen. We hereby report a very rare case of severe neonatal anti-E hemolytic disease due to E minor blood group incompatibility. A term newborn born to a 27-year-old, gravida 3, para 3 mother was referred due to a high and increasing serum bilirubin level despite phototherapy on the 4th day of life. On admission physical examination was normal except for the jaundice, and results of the laboratory investigation demonstrated a moderate-to-severe anemia (hemoglobin 7.8 g/dl) and a severe hemolytic hyperbilirubinemia (serum total and indirect bilirubin levels 36 mg/ dl and 32.8 mg/dl, respectively; reticulocyte count 15%; and a positive direct antiglobulin test). As there was no apparent cause of the hemolytic disease such as Rh or ABO incompatibilities, further investigation (a positive indirect antiglobulin test and a positive irregular anti-E antibody in both the patient and mother, and minor blood group antigen profiles in family members compatible with E minor blood group isoimmunization) revealed the presence of anti-E hemolytic disease due to E minor blood group incompatibility. Two exchange transfusions with a 12-hour-interval were performed with minor blood group compatible fresh whole blood, and the patient was discharged in a healthy condition on the 10th postnatal day. If the most common causes of severe neonatal hemolytic disease such as Rh and ABO incompatibilities cannot be demonstrated in a newborn with significant hemolytic hyperbilirubinemia, anti-E hemolytic disease should strongly be considered in differential diagnosis. It should be kept in mind that a very severe from of minor group antibody hemolytic disease characterized by anemia and severe hyperbilirubinemia many exchange transfusions may be encountered during the course of the disease.
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PMID:Hemolytic disease of the newborn due to isoimmunization with anti-E antibodies: a case report. 1240 39

This review summarizes state-of-the-art and emerging techniques in the antenatal diagnosis of fetal anemia and hemoglobinopathies. Fetal anemia may result from hemolytic disease, hemorrhage, suppression of erythropoiesis, infection (eg, parvovirus B19), or trauma. The clinical laboratory plays an essential role in the evaluation of these disorders by way of the use of various hematologic, biochemical, serologic, cytometric, and molecular genetics methods. Hemoglobinopathies are the most common class of single gene disorders worldwide. The authors have used the example of homozygous alpha-thalassemia major (Hb Barts disease) as a paradigmatic case for antenatal hemoglobinopathy screening. Perhaps the most familiar indication for hematologic screening in pregnancy is HDFN, most commonly in pregnancies previously sensitized to the RhD antigen. All pregnant women, regardless of their past medical or obstetric history or previous antibody screens, should have ABO/Rh blood typing and a red cell antibody screen performed at the first prenatal visit. Long-established methods for assaying FMH (KB method), microcytosis (hemogram with red cell indices), and blood group incompatibility (direct antigen test, serologies) remain critical for rapid, sensitive diagnosis. Analysis of fetal free DNA in maternal plasma holds the promise for rapid, ultrasensitive, and noninvasive detection of many fetal hematologic disorders.
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PMID:Testing for hematologic disorders and complications. 1284 47


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