1/24. Hemoglobin S/O(Arab): thirteen new cases and review of the literature.Hemoglobin S/O(Arab) (Hb S/O(Arab)) is a rare compound heterozygous hemoglobinopathy characterized by the presence of two variant beta-globin chains: beta6Glu --> Val (Hb S) and beta121Glu --> Lys (Hb O(Arab)). The diagnosis of Hb S/O(Arab) requires electrophoresis on both cellulose acetate and citrate agar, since Hb O(Arab) co-migrates with Hb C at alkaline pH and close to Hb S at acidic pH. To date only case reports and small series of patients with Hb S/O(Arab) have been described. To better characterize the clinical and laboratory aspects of this unusual disorder, we reviewed the Duke University Medical Center experience. We identified 13 African-American children and adults with Hb S/O(Arab) ranging in age from 2.7 to 62.5 years. All patients had hemolytic anemia with a median Hb of 8.7 gm/dL (range 6.1-9.9 gm/dL), and a median reticulocyte count of 5.8% (range 1.2-10.3%). The peripheral blood smear typically showed sickled erythrocytes, target cells, polychromasia, and nucleated red blood cells. All 13 patients have had significant clinical sickling events including acute chest syndrome (11), recurrent vasoocclusive painful events (10), dactylitis (7), gallstones (5), nephropathy (4), aplastic crises (2), avascular necrosis (2), leg ulcers (2), cerebrovascular accident (CVA) (1), osteomyelitis (1), and retinopathy (1). Four patients have died, including two from pneumococcal sepsis/meningitis at ages 5 and 10 years, one of acute chest syndrome at age 14 years, and one of multiorgan failure at age 35 years. We conclude that Hb S/O(Arab) disease is a severe sickling hemoglobinopathy with laboratory and clinical manifestations similar to those of homozygous sickle cell anemia.- - - - - - - - - - ranking = 1keywords = hemolytic (Clic here for more details about this article) |
2/24. Hb Mont Saint Aignan [beta128(H6)Ala-->Pro]: a new unstable variant leading to chronic microcytic anemia.Hb Mont Saint-Aignan [beta128(H6)Ala-->Pro] is a mildly unstable variant, associated with hemolytic anemia, marked microcytosis and increased alpha/beta biosynthetic ratio (1.55 versus 1.1 /- 0.1 in the control). The abnormal chain was isolated by selective precipitation with isopropanol and the structural modification determined by protein chemistry methods (reversed phase high performance liquid chromatography and mass spectrometry). Possible mechanisms underlying the beta( )-thalassemia-like expression of this variant are discussed.- - - - - - - - - - ranking = 1keywords = hemolytic (Clic here for more details about this article) |
3/24. A double heterozygous hemoglobin. Hemoglobin OIndonesia and hemoglobin DPunjab in an individual.During surveys for abnormal hemoglobins in iran, an individual was found to have four electrophoretically distinct hemoglobins. The abnormality was found only in the father of the propositus, in two of the father's sisters, and in three brothers and sisters of the propositus. Investigations revealed that the four hemoglobin components are the result of a double heterozygosity between an alpha-chain variant (Hb OIndonesia) and a beta-chain variant (Hb DPunjab). The presence of the abnormal hemoglobins was not associated with hemolytic disorders or obvious clinical symptoms.- - - - - - - - - - ranking = 1keywords = hemolytic (Clic here for more details about this article) |
4/24. Allogeneic bone marrow transplantation in a child with hemoglobinopathy olmsted.The authors describe the first successful bone marrow transplant for the treatment of hemoglobinopathy Olmsted in a boy who presented with severe transfusion-dependent hemolytic anemia and jaundice at age 4 months. He received bone marrow from an HLA-identical sibling with normal hemoglobin electrophoresis after conditioning with busulfan, cyclophosphamide, and antithymocyte globulin when he was 18 months old. The posttransplant course was uneventful. Two years after transplantation the patient has a normal hemoglobin level without evidence of hemolysis. dna analysis shows 100% chimerism of donor cell origin, confirming full engraftment with normal hematopoietic cells.- - - - - - - - - - ranking = 1keywords = hemolytic (Clic here for more details about this article) |
5/24. Hb Leslie, an unstable hemoglobin due to deletion of glutaminyl residue beta 131 (H9) occurring in association with beta0-thalassemia, HbC, and HbS.A new unstable hemoglobin, Hb Leslie, has been observed in three generations of a georgia family. The propositus, a 42-yr-old black veteran with hemolytic anemia and splenomegaly, has a hemoglobin variant with an electrophoretic mobility similar to that of hemoglobin F. The variant comprises about 85% of the total hemoglobin and was isolated by chromatography. Chemical analysis has identified the abnormality as a deletion of the glutaminyl residue in position 131 (H9) of the beta-chain. Deletion of this critical residue which participates in the alpha1beta1 contact causes decreased stability of the hemoglobin without significant changes in functional properties or morphologic abnormalities in the erythrocyte. family studies revealed hemoglobin Leslie occurring in combination with beta0-thalassemia, HbS, and HbC. All persons with the various Hb Leslie combinations, including the propositus, have no clinical manifestations other than anemia. In some the anemia is fully compensated. There is no history of drug-associated hemolysis.- - - - - - - - - - ranking = 1keywords = hemolytic (Clic here for more details about this article) |
6/24. Hemoglobin Sabine [beta 91 (F7) Leu-->Pro]: occurrence in a Sardinian individual with hemolytic anemia and inclusion bodies.BACKGROUND. Hemoglobin (Hb) Sabine (beta 91 Leu-->Pro) is an unstable variant detected for the first time in a 16-year-old Scottish-English-German girl affected by moderately severe hemolytic anemia. A second case was described in a patient of Yugoslavian descent. We report another case of this Hb variant arising as a de novo mutation in a Sardinian patient. methods. Definition of the mutation was obtained by dna direct sequencing on amplified beta-globin gene, as well as by structural analysis of the hemoglobin variant. RESULTS AND CONCLUSION. The patient presented a moderately severe hemolytic anemia with red blood cell inclusion bodies. Hemoglobin electrophoresis showed that quantitatively the abnormal fraction represented 9% of the total Hb amount. beta globin gene analysis revealed a single nucleotide substitution, T-->C, at codon 91, which gives rise to a leucine-->proline substitution. Structural analysis of the variant confirmed the amino acid substitution (Leu-->Pro) predicted by dna sequencing.- - - - - - - - - - ranking = 6keywords = hemolytic (Clic here for more details about this article) |
7/24. A young girl with hemolytic anemia and elevated hemoglobin F.The non-immune, non-spherocytic anemias result from multiple potential etiologies. We report a 16-year-old girl, who was presented with a long-standing anemia and normal blood screening tests except an elevated hemoglobin F. Her diagnosis of unstable hemoglobinopathy was made only after gene sequencing of the beta-globin chain.- - - - - - - - - - ranking = 4keywords = hemolytic (Clic here for more details about this article) |
8/24. Haemoglobinopathy in pregnancy: diagnosis and treatment.Haemoglobinopathies differ in geographic prevalence but together are amongst the most common genetic disorders worldwide. Despite huge diagnostic progress, therapeutic options remain limited, with many treatments still at the experimental stage, no more so than in pregnancy: not only does the presence of a fetus subject treatments to greater limitations, but also any worsening of the anaemia as pregnancy progresses results in higher fetomaternal morbidity and mortality. Anaemia weakens the response to peripartum blood loss, with the risk of postpartum complications. Until recently the standard conventional therapy for severe anaemia was (repeated) blood transfusion, with its well-known risks. Recombinant human erythropoietin (rhEPO) can induce fetal haemoglobin and is a safer, if less immediately effective, alternative for the correction of anaemia in pregnant patients with haemoglobinopathy.- - - - - - - - - - ranking = 0.80922080706636keywords = anaemia (Clic here for more details about this article) |
9/24. Hb Bristol-Alesha presenting thalassemia-type hyperunstable hemoglobinopathy.Hemoglobin (Hb) Bristol-Alesha is caused by a GTG --> ATG mutation at codon 67 in the Hb beta chain, resulting in abnormal beta globin chains with mutated molecules from normal beta67 valine (Val) to beta67 methionine (Met) or beta67 aspartate (Asp). We describe a Japanese child with this rare hemoglobinopathy and a very unstable Hb molecule phenotype. The diagnosis of hemolytic anemia was made when the patient was 6 months of age. Development of marked splenomegaly necessitated red blood cell transfusions twice a month. After splenectomy when the patient was 4 years of age, laboratory findings of hemolytic anemia became more prominent. Specific abnormal Hb molecules initially were not detected, and the alpha/beta globin synthesis ratio was abnormal at 2.22. After splenectomy, we identified the presence of abnormal beta-globin chains with a beta67Val:beta67Met:beta67Asp molecule ratio of 74:11:15. We speculate that the high fraction of the beta67Met molecule in this patient, compared with that in previously reported cases, caused extreme Hb instability, which resulted in thalassemic hyperunstable hemoglobinopathy and very severe clinical findings.- - - - - - - - - - ranking = 2keywords = hemolytic (Clic here for more details about this article) |
10/24. Evaluation of pulse oximetry in anemia from hemoglobin-H disease.A patient with hemoglobin-H (Hb-H) disease developed an acute hemolytic crisis after treatment with trimethoprim and sulfamethoxazole. Despite her poor clinical condition and profound anemia (Hb, 2.7 g/dL), pulse oximetry continued to demonstrate a high O2 saturation percentage. Manipulation of beer's law shows that anemia theoretically should not affect pulse oximetry values. The literature describes the effects of dyshemoglobinopathies such as carboxyhemoglobinemia and methemoglobinemia on O2 saturation percentage measured by pulse oximetry, but the effect of genetic hemoglobinopathies on pulse oximetry values is largely unreported. Because most hemoglobinopathies do not significantly change the protein-heme electronic interaction, the values of O2 saturation percentage determined through pulse oximetry should remain clinically valid. Hb-H is an exception to this generalization; as in patients with carboxyhemoglobinemia, pulse oximetry measurements showing high O2 saturation percentage do not correspond to high levels of oxygen available for delivery to tissues.- - - - - - - - - - ranking = 1keywords = hemolytic (Clic here for more details about this article) |
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