Chronic myelomonocytic leukemia associated with hereditary pyruvate kinase deficiency and multiple acquired erythrocyte abnormalities.

A congenital erythrocyte pyruvate kinase (PK) deficiency was found in a 72-year old female patient with chronic myelomonocytic leukemia (CMML). Erythrocyte PK deficiency was associated with an increase in the activity of hexokinase, 6-phosphogluconate dehydrogenase and glutathione peroxidase in erythrocytes as well as a decrease in acetylcholinesterase, glutathione reductase and glucosephosphate isomerase activities. The enzymatic abnormalities were accompanied by alterations in hemoglobin and in i antigen content of erythrocyte membrane. In addition, bone marrow ultrastructural studies showed dyshemopoietic changes in all blood cell lines and especially in erythroblasts. The present findings confirm the close relationship between CMML and acquired dyserythropoietic syndromes and constitute a new observation of the infrequent association of hereditary erythrocyte enzymopathies and leukemia. A survey of the literature is presented.     

Red cell adenylate kinase deficiency: molecular study of 3 new mutations (118G>A, 190G>A,and GAC deletion) associated with hereditary nonspherocytic hemolytic anemia

We report here 2 patients with chronic nonspherocytic hemolytic anemia (CNSHA) and severe red blood cell (RBC) adenylate kinase (AK) deficiency. One of these patients, a boy of Spanish origin, exhibited a neonatal icterus and splenomegaly and required blood transfusions until the age of 2 years. The other patient was a white, American infant born to parents who were first cousins; he also presented with neonatal icterus and anemia. In neither case was psychomotor impairment observed. The first patient was found to be a compound heterozygote for 2 different missense mutations, 118G>A(Gly40Arg) and 190G>A(Gly64Arg) (cDNA sequence first described by Matsuura et al, 1989). The second patient was homozygous for an in-frame deletion (GAC) from nucleotide (nt) 498 to 500 or nt 501 to 503 of the cDNA sequence, predicting deletion of either aspartic acid (Asp) 140 or 141. The crystal structure of porcine cytosolic AK was used as a molecular model to investigate how these mutations may affect enzyme structure and function.     

Recombinant alpha-2b-interferon may restore natural-killer activity in patients with B-chronic lymphocytic leukemia.

In nine patients with CLL treated with chlorambucil followed by alpha-2b-interferon (alpha 2b-IFN), T, B and natural killer (NK) cells and NK activity were studied before entering the study, after chlorambucil treatment, and after administration of alpha 2b-IFN. When considered as a whole, basal NK activity was lower in CLL patients than in controls (21.0% +/- 10.9 versus 40.2% +/- 17.4, p less than 0.001); however, when considered individually, four out of nine patients had normal NK activity at diagnosis. Chlorambucil did not increase global NK activity (21.7% +/- 7.1), whereas alpha 2b-IFN did so (44.3% +/- 19.1). After alpha 2b-IFN only one of seven patients studied had low NK activity. Previously increased absolute counts of CD2+, CD4+, CD8+, CD16+, CD57+ lymphocytes were reversed with chlorambucil treatment to normal levels, while after this therapy CD11b+ and CD19+ cells decreased without reaching normal values. During alpha 2b-IFN therapy, an increase up to normal levels in the percentage of CD16+ (2.7% +/- 3.4 versus 7.7% +/- 6.5, p = 0.04) and CD57+ (3.0% +/- 3.0 versus 8.1% +/- 6.2, p = 0.020) lymphocytes was observed whereas the absolute number of CD19+ B-cells further decreased (5.2 x 10(9)/l +/- 2.5 vs 3.8 x 10(9)/l +/- 2.3), albeit not significantly.     

The value of detecting surface and cytoplasmic antigens in acute myeloid leukaemia

The immunophenotype of leukaemia cells from 60 patients with acute myeloid leukaemia (AML) was analysed with the APAAP technique using a panel of anti-myeloid and lymphoid associated monoclonal antibodies (McAb). Cells from all cases, including three with negative cytochemical features, were labelled by at least one of the anti-myeloid McAb CD13, anti-myeloperoxidase (anti-Mpo), and/or CD14. The most sensitive marker was CD13, since it was positive in 90% of cases. In two out of three AML cases defined as M0-AML, CD13 was expressed in the cytoplasm but not on the membrane; in these three cases peroxidase (Mpo) was not detected by conventional cytochemistry, but could be demonstrated in all of them using the McAb anti-Mpo. The simultaneous expression of CD14 and CD68 McAb was often confined to the M4 and M5 FAB AML subtypes (92% cases) as compared to the others: M1, M2, M3 (18% cases). Lymphoid antigens were rarely positive (TdT+: 13%, CD7+: 15%, CD19+: 5%) and none of the AML cases were CD3+ or CD10+. By contrast, CD4 was expressed in blasts from 44% of cases and this was not restricted to AML with a monocytic component (M4, M5) but also found in other subtypes. There were no significant differences in the clinical or prognostic features according to the positivity or negativity with TdT and CD4. By contrast, expression of CD7 was associated with refractoriness to the treatment or short complete remission duration, although the number of patients is too small to draw firm conclusions. Our findings support the clinical and diagnostic relevance of immunophenotypic studies in AML.     

Congenital methemoglobin-reductase (cytochrome b5 reductase) deficiency associated with mental retardation in a Spanish girl.

Methemoglobinemia and mental retardation associated with NADH-diaphorase deficiency was found in a 2-year-old girl of Spanish origin. She showed no NADH-diaphorase activity in either erythrocytes or leukocytes, but electrophoretic studies of the hemolysate showed traces of an enzyme with normal mobility. Cytochrome b5 reductase activity was also found to be absent in the leukocytes of the propostius. Intermediate NADH-diaphorase activity was found in erythrocytes and leukocytes in her parents and her sister in accordance with the autosomal recessive mode of inheritance of this enzymopathy. The relationship between a generalized cytochrome b5 reductase deficiency and the progressive neurological involvement in our patient is discussed briefly.     

Acquired amegakaryocytic thrombocytopenic purpura associated with immunoglobulin deficiency

Acquired amegakaryocytic thrombocytopenic purpura (AATP) is a haematological disorder characterized by severe thrombocytopenia due to an immunologically induced absence of megakaryocytes in an otherwise normal-appearing bone marrow. A 57-year-old male with a 6-month history of rectal and cutaneous bleeding is reported. Platelet count was 10 X 10(9)/l, while other haematological values were within the normal range, except for the presence of hypogammaglobulinaemia with decreased IgA and IgG. Both platelet median volume and half-life span were normal, and antiplatelet IgG determinations were negative. Bone marrow aspiration and biopsy showed no megakaryocytes, with a normal appearance of erythroblastic and granulopoietic series. An in vitro culture for megakaryocytic progenitor cells did not show any growth of megakaryocyte colonies. No inhibitory effect on the growth of normal marrow megakaryocytic colonies was observed when serum and lymphocytes of the patient were added. Following 4 weeks of prednisone therapy, the platelet count rose to 127 X 10(9)/l and the bone marrow aspirate showed some megakaryocytes. The possible pathogenetic mechanisms of this entity are discussed.     

Molecular Heterogeneity of β-Thalassemia Alleles in Spain and its Importance in the Diagnosis and Prevention of β-Thalassemia Major and Sickle Cell Disorders

In the last 20 years, migratory flows have changed the pattern of β-thalassemia (β-thal) mutations in Catalonia and have also increased β^S prevalence, either alone or in association with β-thal alleles. Characterization of the β gene is needed for genetic counseling for β-thal major and also for sickle cell diseases. The purpose of this study was to investigate the current distribution pattern of β‐thal mutations. Seventy nine individuals were characterized at the molecular level. As a first step, frequent mutations in the Mediterranean region were screened and when none of these mutations were identified, the β-globin gene was sequenced. Screening for common mutations allowed the characterization of 60 individuals. In the remaining 19 cases, 11 different mutations were identified. β-Thalassemia heterogeneity in Spain has markedly increased, leading to the requirement of including new methods for genetic diagnosis. Prevention of β-thal major and sickle cell disease are necessary since their prevalence in Spain is increasing dramatically.