Gene/Protein Disease Symptom Drug Enzyme Compound
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Query: UMLS:C0002895 (sickle cell disease)
 11,747 document(s) hit in 31,850,051 MEDLINE articles (0.00 seconds)

The present study was carried out to determine the evidence of alloimmunization against red blood cells in 364 patients transfused in our center over a period of 4 years (1990-1993). Among these patients, 127 were thalassemic and 182 had sickle cell disease (SCD). In 55 control patients, who received blood matched for the ABO, Rhesus and Kell antigen systems from the outset of transfusion, no immunization was detected. However, in the study group, who initially received blood matched only for ABH and Rh D antigens, the frequency of alloimmunization was 7.76% (24/309). Only one antibody was detected in 15 patients (62.5%) and two or more in 9 patients (37.5%). Alloimmunization concerned the Rhesus system in 58.82% of cases and the Kell system in 26.47%, while the frequency of immunization was significantly lower in patients of less than 5 years as compared to those in the age range 5-10 years (p < 0.001).
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PMID:Red cell alloantibodies in patients with haemoglobinopathies. 789 31

This prospective study was designed to provide the frequencies of the haemoglobin genotypes, ABO and Rh blood groups and their effects on the haematocrit values among pregnant women in Port Harcourt. One hundred and eighty (180) pregnant women at their first clinic attendance and in their first pregnancy (parity - 0) participated in this study. The overall frequencies obtained for ABO and Rh blood groups were: 26.67% for group A, 18.33% for B, 2.22% for AB and 52.78% for O. Rh D positive was 95.56% while Rh D negative was 4.44%. The frequencies of haemoglobin genotypes were 70.00% for HbAA, 29.44% for HbAS and 0.56% for HbSS. HbAC and SC did not occur in this study population. The mean haematocrit value was 34.64%. This was found to be independent of the ABO and Rh blood groups (P > 0.05). On the other hand, haemoglobin genotypes were found to exert significant effects on the haematocrit values (F = 8.01, P = 0.0005). No significant relationship was found to exist between age and the haematocrit values. (F = 0.91, P > 0.05). Since pregnancy in sickle cell disease is associated with morbidity, proper antenatal monitoring and counselling will be necessary to prevent fatal outcomes.
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PMID:An assessment of the clinical utility of routine antenatal screening of pregnant women at first clinic attendance for haemoglobin genotypes, haematocrit, ABO and Rh blood groups in Port Harcourt, Nigeria. 1662 95

Red blood cell (RBC) transfusion is a key treatment of patients with sickle cell disease (SCD) but remains complicated by RBC immunization. In the present study, we evaluated the effects of antigen matching for Rh D, C, and E, and K and transfusion from African American donors in 182 patients with SCD. Overall, 71 (58%) chronic and 9 (15%) episodically transfused patients were alloimmunized. Fifty-five (45%) chronic and 7 (12%) episodically transfused patients were Rh immunized. Of 146 antibodies identified, 91 were unexplained Rh antibodies, one-third of which were associated with laboratory evidence of delayed transfusion reactions. Fifty-six antibodies occurred in patients whose RBCs were phenotypically positive for the corresponding Rh antigen and 35 in patients whose RBCs lacked the antigen and were transfused with Rh-matched RBCs. High-resolution RH genotyping revealed variant alleles in 87% of individuals. These data describe the prevalence of Rh alloimmunization in patients with SCD transfused with phenotypic Rh-matched African American RBCs. Our results suggest that altered RH alleles in both the patients and in the donors contributed to Rh alloimmunization in this study. Whether RH genotyping of patients and minority donors will reduce Rh alloimmunization in SCD needs to be examined.
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PMID:High prevalence of red blood cell alloimmunization in sickle cell disease despite transfusion from Rh-matched minority donors. 2392 36

Rh alloimmunization remains a challenge for patients with sickle cell disease (SCD) despite transfusion of serologic Rh C, E, and K antigen-matched red cells. Inheritance of altered RH alleles contributes to the prevalence of Rh antibodies after blood transfusion in patients with SCD and explains approximately one-third of cases. The remainder seem to be stimulated by altered Rh proteins on African American donor red cells. Matching patients with donors on the basis of RH genotype may mitigate Rh alloimmunization, but the feasibility and resources required are not known. We compared RH allele frequencies between patients with SCD (n = 857) and African American donors (n = 587) and showed that RH allele frequencies are similar. Overall, 29% of RHD and 53% of RHCE alleles are altered in patients and African American donors. We modeled RH genotype matching compared with serologic Rh D, C, and E, along with K antigen matching, and found that approximately twice the number of African American donors would be required for RH genotype vs Rh serologic matching at our institution. We demonstrated that African American donor recruitment is necessary to maintain an adequate supply of C-, E-, and K-negative donor units to avoid depleting the Rh-negative (RhD-) blood supply. Our results suggest that prophylactic RH genetic matching for patients with SCD is feasible with a donor pool comprised primarily of African-Americans and would optimize the use of our existing minority donor inventory. The current cost of RH genotyping all minority donors and management of the data remain limiting factors.
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PMID:RH genotype matching for transfusion support in sickle cell disease. 3021 39