Biomedical subjects

A López Borrasca

Publications and source records attributed to A López Borrasca.

At least 19 recordsLinked to original sources

PubMed1992

Development of acute leukaemia after idiopathic myelofibrosis.

AIMS: To determine the characteristics of blastic transformation of idiopathic myelofibrosis. METHODS: The clinical and haematological features, as well as the morphological characteristics of blast cells, were analysed in nine adults with blast transformation. RESULTS: Most of the patients were male and had enlarged spleens and livers. Five of the patients had normal platelet counts, while all had pronounced anaemia and a moderate degree of leucocytosis. The duration of the acute phase was usually short: 16 (SD 8) weeks. Most myeloid cell lineages--granulocytic, monocytic, and megakaryocytic--were similarly distributed. One patient also had a hybrid (lymphoid-myeloid) phenotype. The morphological assessment of blast cells agreed with immunophenotyping in five out of the nine cases. The onset of the blastic phase was not related to previous treatment. CONCLUSIONS: A pluripotential stem cell with preferential myeloid commitment would be the target cell of blast transformation in idiopathic myelofibrosis. Our immunophenotypic data do not support the concept of a preferential association between megakaryocytic lineage and the acute transformation of idiopathic myelofibrosis. The absence of previous treatment in some cases suggests that this kind of evolution is part of the natural history of idiopathic myelofibrosis.

Acute Disease↗

PubMed1991

[Clinico-hematological characteristics of acute transformation of chronic myeloproliferative syndromes].

BACKGROUND: The aim of the present study was to analyze the blastic transformation occurring during chronic myeloproliferative diseases (CMPD) and to establish the differences between them. METHODS: The clinical and hematological characteristics of 54 patients in blastic crisis (BC) of a CMPD were analyzed: 40 chronic myelogenous leukemias (CML), 9 idiopathic myelofibroses (IMF), 4 polycythemia vera (PV), and one essential thrombocythemia (ET). The results were analyzed by the BMDP statistical program. RESULTS: The BC of CML appeared in younger patients (p less than 0.05). Only in this group did some patients achieve complete remission. Moreover, in this BC a greater incidence of visceromegalies and leukocytoses were observed. The BC of the IMF patients led to marked anemia (p less than 0.01) and bone marrow infiltration (p less than 0.05); these leukemias were more frequent in males and began with lymphadenopathies and visceromegalies. The transformations of PV were preceded by a longer chronic phase and had a lower incidence of visceromegalies and a nearly normal hemoglobin count value. The patient with acute leukemia secondary to ET did not display visceromegalies but did have anemia, leukopenia and a normal platelet count. None of the four groups responded to therapy, and their survival was short. CONCLUSIONS: Blast transformations of different myeloproliferative disorders have their own idiosynchratic clinical and hematological characteristics, some of these may be related to the chronic phase of disease.

Age Factors↗

PubMed1991

Acute leukemia after a primary myelodysplastic syndrome: immunophenotypic, genotypic, and clinical characteristics.

We studied the nature of blast cells in 41 patients with acute leukemia following a previous primary myelodysplastic syndrome (MDS) by a combined multiparameter analysis including morphologic, immunophenotypic, and molecular genetic (Igs, T-cell receptor (TCR)-beta, -gamma, and -delta and the major breakpoint cluster region [M-bcr]) investigations. In addition, the clinical and hematologic characteristics according to the immunophenotype of blast cells were analyzed. Our results show that, although the granulocytic and/or monocytic lineages are those most commonly involved in these acute leukemias, other cell components, including the megakaryocytic and lymphoid, may be present (12% and 15% of the cases, respectively). Moreover, both morphologic and phenotypic studies show the frequent coexistence of two or three cell populations. Interestingly, in all cases the lymphoblastic component constantly displayed an early B phenotype (CD19+, CD10-, TdT+). Upon analyzing whether the type of MDS conditioned any differences in the immunophenotype of blast cells, we observed that, although the lymphoid lineage may be involved in all MDS subgroups, some differences emerge within the myeloid leukemic transformations. Thus, the refractory anemias with excess of blasts (RAEB) and RAEB in transformation displayed a significantly higher incidence of myeloblastic and megakaryoblastic transformations, while in the RA, RA with ring sideroblasts and chronic myelomonocytic leukemia, the granulo-monocytic phenotype predominated. In addition, our results show that the clinical and hematologic characteristics of these patients may be partially related to the immunophenotype of the blast cells. Ig heavy chain gene rearrangements were found in two of 19 patients analyzed (11%), one with a hybrid leukemia (lymphoid-myeloid) and the other with a granulo-monocytic phenotype. Two other hybrid transformations analyzed were in germline configuration. Gamma and delta gene rearrangements were found in 21% and 37% of these acute transformation, respectively. The TCR-beta and M-bcr were in germline configuration in all 19 cases studied. In summary, immunophenotype and molecular studies point to a pluripotent stem cell with preferential myeloid commitment as the target cell of leukemias following a primary MDS.

Acute Disease↗

PubMed1991

[Antibodies against hepatitis C virus in hemophiliacs: correlation with peripheral blood lymphocyte populations].

The presence of antibodies (Abs) against hepatitis C virus (HCV) was analyzed in 26 haemophiliac patients; a prevalence of 38% was found in the total series and 56% in the treated patients. There were no cases with a positive serology among the three patients who had only received pasteurized factor. The frequency of detection of anti-HCV was higher in the patients who had a positive serology for HIV (67%) and hepatitis B virus (56%) than in the seronegative patients (24 and 29%, respectively). The patients with HCV Abs showed a decrease in the helper (CD4+) lymphocytic population, mainly due to the decrease in the helper inducer (CD4+/Leu8-) cells, such alterations being more evident in the patients who also were HIV+ who showed as well an increase in the T-cell activated lymphocytes (CD3+/la+) and a decrease in CD16+ natural killer cells. These results suggest that the lymphocytic alterations found in the patients with anti-HCV Abs are not specific and would rather be related to the presence or not of HIV infection.

Hemophilia A↗

PubMed1991

Heterogeneity of T cell lymphoblastic leukaemias.

Twenty eight out of 170 consecutive cases of acute lymphoblastic leukaemia (ALL) were examined. They were of T cell origin, with the following distribution: seven (28%) cases had pre-T or prothymic features; nine (36%) cases showed early thymocytic features, six (24%) had cortical features; and three (12%) had a "mature" phenotype. The remaining three cases could not be sub-classified. A striking finding was that pre-T ALL differed from intrathymic ALL not only in the absence of both E rosettes and intrathymic differentiation antigens, but also in the expression of two non-lineage specific antigens HLA-DR and CD10. Both antigens appear in the bone marrow from the very first stages of lymphoid differentiation, implying that the origin for pre-T ALL is bone marrow. A comparison of the clinical features of pre-T and thymic ALL showed that pre-T ALL disease showed a pattern more similar to non-T ALL disease: a lower incidence of mediastinal mass, absence of extrahaematopoietic disease, lower white cell counts and haemoglobin concentrations, and a higher incidence of bone pain. No obvious difference in response to treatment was apparent. The results show that T-ALL is not only a heterogeneous immunological group but also suggest that it may have different origins: bone marrow for pre-T ALL and the thymus for thymic ALL.

Adolescent↗

PubMed1991

[Phenotypic changes in refractory and relapse acute lymphoblastic leukemias].

Out of a group of 220 acute lymphoblastic leukaemias (ALL) with phenotypic study at diagnosis, 18 were selected on which sequential studies were performed due to relapse (15 cases) or to lack of achievement of complete remission (primary resistant ALL, 3 cases). The purpose of this study was to analyse the incidence and characteristics of the possible antigenic changes with regard to the diagnosis. Along with the classic markers, a panel comprised of 20 monoclonal antibodies against lymphoid and myeloid antigens was used. Major phenotypic changes (acquisition of myeloid antigens CD13 and CD33) were found only in one case amongst the relapsing ALL (7%). Seven other patients (47%) showed minor phenotyping changes, including: 1) acquisition or loss of antigens (2 cases); 2) changes in more then 50% of any antigen's expression (4 cases); 3) both (1 case). These results might suggest that antigenic changes are rather frequent in relapsing ALL; however, none of such changes modified in our experience the phenotypic diagnosis so any change of this last should be regarded as an exceptional event. The majority of these antigenic changes consisted of the loss of maturation antigens (CD20) or acquisition of early markers (TdT, HLA-DR) or activation markers (CD38); this would mean that the relapsing blast cells show a functional status of activation and proliferation, with a phenotype more immature than that of the diagnosis, thus explaining the poorer prognosis of the patients in relapse. No phenotypic changes were found in the primary resistant ALL, which may indicate the persistence of the original cell clone without any alteration.

Adult↗

PubMed1990

[Usefulness of the immunologic phenotype in the diagnosis of chronic lymphoproliferative syndromes with splenomegaly as the dominant clinical manifestation].

From a total number of 221 patients with leukaemic lymphoproliferative syndromes studied at the Hospital dos Capuchos, in Lisbon, seven patients whose cell morphology differed from that of "classical" lymphoproliferative syndromes were separated; marked splenomegaly without lymph node enlargement was present in all of them. Immunophenotypic studies confirmed B-cell origin of the lymphoproliferation in the seven patients. Small lymphocytes with mature appearance predominated in three of these cases, presenting as: a) the only cell population (with immunophenotype RR+, FMC7-, CD5+), b) along with a significant amount of prolymphocytes (RR+, CD5+, FMC7+), c) accompanying a population of cells with lymphoplasmacytoid differentiation (RR-, CD5-, CD38+, associated to serum monoclonal IgM). Those data strongly suggested that these three lymphoproliferative syndromes corresponded, respectively, to a classic B-cell chronic lymphocytic leukaemia, a chronic lymphocytic leukaemia with prolymphocytes, and an immunocytoma. In three other cases the morphology of the proliferating cells was intermediate between prolymphocytes and hairy cells (i.e., variant hairy cells) and they strongly reacted with monoclonal antibodies FMC7 and LeuM5 (CD11c), showing low positivity with antigens CD5 and CD25, in the absence of receptors for mouse red blood cells. The remaining B-cell lymphoproliferative syndrome studied had small centrocytes in peripheral blood, their phenotype being RR-, CD5+, FMC7+/-, CD10+ and CD38+, which suggested a centrofollicular lymphoma with leukaemic expression. In summary, the present study seems to confirm the heterogeneity of the chronic lymphoproliferative syndromes showing splenomegaly as an outstanding clinical feature. Immunophenotype along with cell morphology are important in the differential diagnosis, especially whenever splenectomy cannot be carried out, in order to choose the appropriate therapy.

Antigens, Differentiation↗

PubMed1989