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Biomedical subjects

R Lafuente

Publications and source records attributed to R Lafuente.

At least 19 recordsLinked to original sources
PubMed1990

Abnormal chromatin clumping in leucocytes: a clue to a new subtype of myelodysplastic syndrome.

We report 6 patients with myelodysplastic syndrome, all of whom showed a bizarre nuclear anomaly within the neutrophils that was characterized by extensive clumping of chromatin into large blocks separated by clear zones, generally associated with a lack of segmentation. Anaemia, thrombocytopenia, variable leucocyte counts with leucoerythroblastic picture, marrow hypercellularity with granulocytic hyperplasia and moderate dysplastic changes in erythroblastic and megakaryocytic lines were present at diagnosis. 2 patients had normal karyotypes and a 3 showed a deletion of chromosome 14. 5 out of 6 patients had pneumonia at diagnosis. The median survival was short (5 months) and haemorrhagic complications were the cause of death in 4 patients. The clinical features and the evolution of these and other reported cases suggest that the presence of abnormal chromatin clumping in leucocytes might be a clue to a new subtype of myelodysplastic syndrome.

Aged↗
PubMed1990

[Erythroid colonies derived from BFU-E from the bone marrow in a patient with type I congenital dyserythropoietic anemia].

The findings of in vitro culture of bone-marrow BFU-E from a patient with type I dyserythropoietic anaemia are reported, scarce data being seemingly available in the literature. The number of BFU-E in the culture was increased four-fold with respect to the normal values. The morphologic study of the colonies showed in all cases varying number of erythroblasts with internuclear bridges (5-20%). Upon ultrastructural examination of the colonies, a great number of erythroblasts exhibited morphologic alterations, spongy chromatin and internuclear bridges being commonest. These findings suggest that an alteration of the progenitor erythroid cells exists in type I dyserythropoietic anaemia, whereas the morphological defects appreciated show great variation in the progeny of each BFU-E.

Adult↗
PubMed1989

[Pseudohemopathy caused by rhabdomyosarcoma].

A 26-year-old male with a primary rhabdomyosarcoma of maxillary sinus is reported. The tumor was initially mistaken for an anaplastic Ki-1 positive anaplastic lymphoma in the histological preparation, owing to its high indifferentiation degree. After a smear study it was categorized as IEA, and chemotherapy of CHOP type was started; after two courses, local telecobalt therapy was given. After this was completed, the disease showed a progression, involving the bone marrow and resulting in clinical and cytological features consistent with acute leukemia. At that time we saw the patient for the first time. He is presently in complete remission after having started polychemotherapy of CVADIC type. After a commentary on the major study steps that led to the diagnosis, the crucial role of electron microscopy and, particularly, immunocytology for the correct identification of anaplastic tumors is emphasized.

Adult↗
PubMed1989

Circulating erythroid and megakaryocytic progenitors in polycythaemia vera and essential thrombocythaemia.

We studied the behaviour in culture of erythroid and megakaryocyte progenitor cells (BFU-E, CFU-MK) obtained from peripheral blood (PB) in 38 patients: 15 with essential thrombocythaemia, 3 with reactive thrombocytosis, 16 with polycythaemia vera and 4 with secondary polyglobulia. Clonal erythroid growth without added erythropoietin was observed in all patients with polycythaemia vera and in 5 out of 15 with essential thrombocythaemia, but in none of the patients with reactive thrombocytosis or secondary polyglobulia or in controls. When the CFU-MK were cultured without phytohaemagglutinin-stimulated medium (PHA-LCM), all patients with essential thrombocythaemia and 7 out of 16 with polycythaemia vera showed circulating CFU-MK but none of those with reactive thrombocytosis or secondary polyglobulia or controls did so. This study indicates that the growth in vitro of megakaryocytic and erythroid progenitors from such a readily available source as peripheral blood can be valuable in the diagnosis of certain borderline cases of thrombocytosis or erythrocytosis.

Cells, Cultured↗
PubMed1986

Acute nonlymphocytic leukemia (M7 subtype) with erythrocytic internalization.

A case of acute nonlymphocytic leukemia of megakaryocytic lineage or M7 with a conspicuous phenomenon of erythrocytic internalization present in nearly 3% of the leukemic megakaryocytic precursors (LMP) is reported. The phagocytosis was detected at light microscopy and ultrastructural levels. The erythrocyte might have reached the interior of the LMP through cytoplasmic vacuoles that are connected with the extracellular space and that can be considered rudimentary equivalents of the demarcation membrane system (DMS). Erythrocytic internalization is not a specific feature of the mononuclear phagocytic system and can be misleading in the classification of undifferentiated blast cells.

Bone Marrow↗
PubMed1986

Acquired refractory anaemia with excess of blasts of promegakaryoblastic type.

A case of acquired refractory anaemia with excess of blasts (RAEB) of the promegakaryoblastic type is described. The promegakaryoblastic origin was demonstrated by means of ultrastructural cytochemistry (platelet peroxidase) and immunological methods. The blasts were also 5'-Nucleotidase positive. After a stable course over 2.5 years the patient died from hematological failure, his marrow demonstrating a high degree of fibrosis.

Anemia, Refractory↗
PubMed1986

Platelet peroxidase of circulating thrombocytes in acquired refractory anaemias.

The platelet peroxidase (PPO) content of circulating thrombocytes was determined in 10 healthy controls and in 18 cases of acquired refractory anaemia (2 with refractory anaemia, 4 with sideroblastic refractory anaemia, 8 with refractory anaemia with excess of blasts, 3 with refractory anaemia in transformation and 1 with chronic myelomonocytic leukaemia). The thrombocytes of the controls were invariably PPO-positive. No peroxidase deficiency was found in the 4 patients with sideroblastic refractory anaemia. Of the remaining 14 cases PPO-positive and PPO-negative thrombocytes coexisted in 8. Only in 1 case of refractory anaemia with excess of blasts were circulating platelet peroxidase-positive micromegakaryocytes demonstrated. PPO deficiency seems to be an important dysthrombopoietic feature detectable only at an ultrastructural level.

Anemia↗