Successful percutaneous transluminal coronary angioplasty for acute myocardial infarction in von Willebrand's disease.

An elderly woman with mild von Willebrand's disease presented with acute myocardial infarction. Percutaneous transluminal coronary angioplasty, to mechanically disrupt the thrombus without anticoagulation, was successfully undertaken. Haemostatic cover was also avoided.

Acute Myeloid Leukaemia Following Matched Allogeneic Bone Marrow Transplantation for T-Cell Lymphoblastic Lymphoma.

It is now commonly acknowledged that cells from some acute leukaemias may bear both myeloid and lymphoid markers at diagnosis, or that relapse following initial treatment may occur, with blast cells phenotypically different from those seen at initial diagnosis. Patients showing evidence of bi-linear disease seem to carry a worse prognosis for cure. Here, a case of T-cell lymphoblastic lymphoma is reported, who relapsed with acute myeloblastic leukaemia, following allogeneic bone marrow transplantation. Early diagnosis of disease with lymphoid and myeloid features is therefore warranted, so that intensive treatment programmes may be offered, in anticipation of permanent cure.

Blood rheology and proliferative retinopathy in sickle cell-haemoglobin C disease.

Haematological and rheological (plasma and serum viscosity, whole blood viscosity, and erythrocyte filterability) factors were studied in 31 age-sex matched pairs of patients with sickle cell haemoglobin C disease with and without proliferative sickle retinopathy (PSR). Patients with PSR had significantly higher mean cell haemoglobin and lower Hb F levels on average than the matched controls, but the viscosity and erythrocyte filtration indices did not differ between the 2 groups. There was, therefore, no evidence of rheological differences between patients with and without PSR at the time of the study, although transient rheological abnormalities at the time of development of PSR could not be excluded. Prospective longitudinal studies of rheology before, during, and after the development of PSR would be necessary to detect such changes.

Leucocyte removal prior to study of erythrocyte deformability.

Positive-pressure and initial-flow-rate (Hémorhéomètre) methods for the study of erythrocyte filtration through 5 micron diameter pores are highly sensitive to the presence of contaminating leucocytes in the erythrocyte test suspension. A pre-filtration step, in which heparinised or EDTA-anticoagulated whole-blood was passed through a column of Imugard IG500 cotton wool, was therefore developed. This procedure removed contaminating platelets and leucocytes, but not erythrocyte sub-populations, and is likely to improve the sensitivity and specificity of erythrocyte filtration techniques.

Anticoagulants and erythrocyte filterability.

Positive-pressure and initial-flow-rate (Hémorhéomètre) filtration systems were used to study the deformability of erythrocytes from whole blood stored in EDTA or heparin. When all contaminating platelets and leucocytes were removed from the erythrocyte suspension there was no significant anticoagulant effect on erythrocyte filtration. Blood may therefore be stored in K2EDTA (1.5 mg/ml blood) or lithium heparin (15 IU/ml blood) for up to 6 hours at room temperature prior to measurement of erythrocyte filterability.

Preservation of deformability (filterability) of sickle cells by BW12C during progressive deoxygenation.

Venous blood from patients with sickle-cell disease in the steady state or in crisis was progressively deoxygenated in vitro to study the effect of BW12C, a new compound designed to stabilize haemoglobin in the oxy-conformation, on the deformability (filterability) of washed erythrocytes. At a final concentration of 1.5 mM, BW12C significantly increased erythrocyte deformability, compared with no added compound, at all levels of deoxygenation below normal arterial PO2. At concentrations of 3.0 and 5.0 mM, BW12C prevented any significant reduction of erythrocyte deformability, or increase in sickled cells, with deoxygenation down to PO2 values below the normal venous level. These in vitro results demonstrate the considerable potential, as an anti-sickling agent, of this novel compound.

Effect of alpha thalassaemia on the rheology of homozygous sickle cell disease.

A study of rheological determinants (plasma viscosity, whole-blood viscosity, and erythrocyte deformability) was made in 24 matched pairs of patients with homozygous sickle cell disease, with and without homozygous alpha-thalassaemia 2. Patients with coexisting alpha-thalassaemia showed a significant increase in erythrocyte deformability measured as filtration of washed erythrocytes through 5 micron diameter pores and also as viscosity of whole blood at high shear rate (230s-1) and standard haematocrit (0.45). This rheological advantage may explain the beneficial effect of alpha-thalassaemia 2 on haematological parameters and clinical events in homozygous sickle cell disease.

Effect of alpha thalassaemia on the rheology of homozygous sickle cell disease

A study of rheological determinants (plasma viscosity, whole-blood viscosity, and erythrocyte deformability) was made in 24 matched pairs of patients with homozygous sickle cell disease, with and without homozygous x-thalassaemia. Patients with coexisting x-thalassaemia showed a significant increase in erythrocyte deformability measured as filtration of washed erythrocytes through 5 um diameter pores and also as viscosity of whole blood at high shear rate (230s-1) and standard haematocrit (0.45). This rheological advantage may explain the beneficial effect of x-thalassaemia 2 on haematological parameters and clinical events in homozygous sickle cell disease (AU)

Erythrocyte deformability in sickle-cell crisis.

A serial study of erythrocyte deformability, plasma viscosity, and whole-blood viscosity has been made during 10 sickle-cell vaso-occlusive crises. The peak serum lactate dehydrogenase level was used to confirm the duration of crisis and the rheological changes were compared with 19 estimations made on the same patients when asymptomatic. Erythrocyte deformability, measured by filtration of washed erythrocytes through polycarbonate filters of 5 microgram pore size, was significantly reduced on day 1 of crisis and, in one additional patient, this occurred 24 h before the onset of pain. There was no increase in irreversibly-sick-led-cell counts and plasma- and blood-viscosity did not increase significantly until day 5 of crisis, in parallel with the acute-phase rise in plasma fibrinogen. Measurement of erythrocyte filterability is therefore a valuable technique for investigating the pathogenesis of the early stages of sickle-cell crisis.

Histiocytic medullary reticulosis following acute lymphoblastic leukemia.

A 2-year-old male with acute lymphocytic leukemia died with histiocytic reticulosis 19 weeks later. A comparison with previously reported cases is made, and the relationship of ALL and HMR is discussed.

Efficiency of haematological screening tests for detecting disease.

A new "intermediate' reference (normal) range for the erythrocyte sedimentation rate has been compared with published "low' and "high' reference ranges in a study of 354 hospital patients. The "intermediate' range showed superior balance between sensitivity and specificity in the detection of disease-induced plasma protein abnormalities and and gave a test efficiency of 81.9%; this reference range can therefore be recommended for routine use in the diagnostic laboratory. Four other screening tests (whole-blood viscosity, plasma viscosity, zeta sedimentation ratio, and C-reactive protein level) were compared in the same 354 patients. Whole-blood viscosity proved to be unsuitable as a screening test (efficiency 44.8%) but the three other tests showed good balance between sensitivity and specificity and gave a test efficiency of 74.4-79.7%.

Platelet hyperactivity in sickle-cell disease: a consequence of hyposplenism.

Platelet function was measured on 29 occasions in 16 adult patients in the asymptomatic steady state of sickle-cell anaemia. There was a significant increase in platelet number and micro-aggregate formation, and a lower aggregation threshold with adenosine diphosphate, compared with 23 healthy controls. Similar changes were found, however, in 12 splenectomised patients without sickle-cell diseases. The platelet hyperactivity of the sickle-cell steady state therefore reflects an increased circulating population of young, metabolically active platelets resulting from previous autosplenectomy.

Congenital dyserythropoietic anaemia with unusual cytoplasmic inclusions.

A case of congenital dyserythropoietic anaemia is described which appears to be at variance with the accepted classification. The morphological findings are of normoblastic hyperplasia with marked cytoplasmic vacuolation. Electron microscopy shows these to be myelin figures in all stages of erythroid differentiation.

Absorption, excretion, and utilization of an intramuscular iron-poly (sorbitol-gluconic acid) complex, Ferastral.

An iron-poly (sorbitol-gluconic acid) complex (Ferastral) labelled with 59Fe was administered by intramuscular injection to clinically and haematologically normal male volunteers. Urinary excretion of radioactivity was measured for the first 48 hours following injection, and was 2%-10% of the administered dose. Disappearance of radioactivity at the site of injection and accumulation of radioactivity in the liver, spleen, and sacrum were measured by external scintillation counting. Plasma radioactivity was measured at intervals for four days and red cell incorporation of 59Fe reached levels of 29%-57.5%. An unexpected finding was that the highest levels of urinary excretion of radioactivity did not coincide with the highest levels of plasma radioactivity.