Bilateral retinal artery occlusion due to mitral valve prolapse.

We report a case of bilateral retinal artery occlusion due to mitral valve prolapse. Most patients with retinal ischaemia in whom it is found have not been previously known to have it. Since it is a common condition it would seem essential that it be included in the differential diagnosis of amaurosis fugax and retinal artery occlusion if future ischaemic events are to be prevented. All patients with retinal ischaemia should have a full cardiovascular examination supplemented by echocardiography.

The M1 Kegworth aircraft disaster: experience in three hospital blood transfusion laboratories and the regional transfusion centre.

Eighty-eight survivors of an aircraft accident on the M1 motorway were taken to three major hospitals, two of which were teaching hospitals, in the immediate vicinity. We describe the effects of this on the three blood transfusion and haematology laboratories concerned and on the regional transfusion centre, describe how the work was processed, and list the lessons learnt.

What happens to the microspherocytosis of hereditary spherocytosis in folate deficiency?

The case is presented of an elderly man in whom hereditary spherocytosis (HS) had been diagnosed many years previously. He also had diverticulitis and was referred because of increasing anaemia (Hb 7.7 g/dl). He was suffering from diarrhoea and anorexia, and was taking a very poor diet. Serum investigations showed low folate and vitamin B12 levels. His blood film, despite the history of HS, showed very few spherocytes, and the red cell osmotic fragility curve was virtually normal. Instead, the blood film showed normocytes and oval macrocytes, mostly with normal central pallor. He was treated with vitamin B12 injections and folic acid tablets. On this treatment, the Hb rapidly rose, the macrocytosis disappeared, the film appearances reverted to the classical picture of HS with large numbers of microspherocytes, and the osmotic fragility curve to the picture of markedly increased fragility typical of HS.

C-reactive protein levels in neutropenic patients with pyrexia.

This study describes the experience of a clinical haematology unit in dealing with pyrexial episodes in 62 patients. Serum C-reactive protein levels were serially estimated and proved to be useful in following the course of the illness. No significant difference could be demonstrated in the C-reactive protein levels of those patients with bacteriologically proven illnesses, those in whom a clinically evident infection was present, and those with a 'pyrexia of unknown origin'. However, those patients in whom disease activity was thought to be responsible for the pyrexia had significantly lower C-reactive protein levels compared with those patients who had a septicaemic illness.

Chronic T cell lymphocytosis: a review of 21 cases.

Twenty-one patients are described with a proliferation of morphologically mature T lymphocytes. The clinical course was chronic in most, and splenic enlargement the main clinical finding; skin involvement and lymphadenopathy were rare. The mean lymphocyte count at presentation was 8 X 10(9)/1 (range 0.75-24 X 10(9)/1). Nineteen of these patients showed some form of cytopenia (18 neutropenia, two red cell aplasia, eight thrombocytopenia) and one had hypogammaglobulinaemia. Seven patients had long-standing arthropathy serologically proven to be rheumatoid arthritis and these had previously been considered to have Felty's syndrome. Five of the group have died (three with an aggressive course), but most have remained stable for prolonged periods with a slow increase in peripheral lymphocyte count and marrow infiltration. Spontaneous regression was never observed but in two patients a prolonged remission was achieved by chemotherapy. The lymphocytes were morphologically and phenotypically homogeneous at presentation and remained so post-splenectomy; they contained azurophilic granules, stained with acid phosphatase but weakly or not at all with alpha napthyl acetate esterase. Membrane phenotyping shows the majority of the cells to be E+, Fc gamma+, OKT3+, OKT8+. Most cells do not stain with OKT1-like reagents and a significant number express HLA-Dr. From these and other reported cases it is clear that this condition represents a distinct entity resulting from the expansion of a subset of cytotoxic/suppressor T cells--the question of the benign or neoplastic nature of the disease remains open. Using T cell-specific antisera and E-rosetting techniques, a small percentage of CLL cases have been shown to be of T-cell origin (TCLL) (Dickler et al, 1973; Lille et al, 1973). Estimates of the percentage vary but in most series T-CLL has been diagnosed in less than 5% (Brouet & Seligmann, 1981), and this is supported by date from the M.R.C. Leukaemia Unit which found T-CLL in only 1.5% of 600 cases of CLL examined by marker studies (D. Catovsky, unpublished). Amongst the published reports of T-CLL a variety of clinical and morphological entities have been described including T prolymphocytic leukaemia (TPLL) (Brouet et al. 1975) and adult T cell disease in Japanese (Uchiyama et al, 1977) and West Indian Caribbean groups (ATLL) (Catovsky et al, 1982). In the original series of Brouet & Seligmann (1981) the group was defined as presenting in middle age with marked hepatosplenomegaly, some lymphadenopathy, skin involvement and with an aggressive disease course; peripheral blood and marrow lymphocytosis were variable.(ABSTRACT TRUNCATED AT 400 WORDS)

Characteristics of the cell surface antigen, p72, associated with a variety of human tumours and mitogen-stimulated T-lymphoblasts.

The monoclonal antibody 791T /36, prepared against a human osteogenic sarcoma cell line, 791T , reacts with a variety of human tumours and also mitogen-stimulated PBMN cells. The target antigen as expressed upon 791T cells is a monomeric plasma membrane-associated glycoprotein with an apparent Mr of 72000. By quantitative flow cytofluorimetry, approx. 10(5) antibody molecules bound per cell to T-lymphoblasts induced with PHA or Con A, whereas only a few thousand antibody molecules bound per cell to unstimulated cells, so that the antigen may be classified as a lymphocyte activation antigen. On lymphoblasts, the 791T /36 again reacted with a protein with an apparent Mr of 72000. This antigen therefore has a dual role as a tumour marker and lymphocyte activation antigen which may be implicated in the regulation of cell proliferation.

Synthesis of procoagulant antihaemophilic factor in vitro.

The cells which produce the procoagulant part of antihaemophilic factor (factor VIII-C) in normal people have remained unknown. Normal blood leucocytes cultured in vitro with phytohaemagglutinin synthesised a procoagulant with the properties of factor VIII-C. The procoagulant was inhibited by human VIII-C inhibitor and itself absorbed human VIII-C inhibitor--properties which are regarded as specific for factor VIII-C. Unexpectedly, cultured leucocytes from haemophiliacs also synthesised the procoagulant in similar amounts. Possible explanations and implications of these findings are briefly considered.

Mononuclear cell-membrane "fluidity": a study in some haematological malignancies.

The polarization of fluorescence from diphenyl hexatriene embedded in the membranes of intact peripheral-blood mononuclear cells has been measured and used to assess the "microviscosity" or fluidity of the membrane. Cell preparations were examined from patients with various types of leukaemia and related conditions in which circulating primitive cells may occur. Significantly lower fluorescence polarization values were obtained in all samples from patients with chronic lymphocytic leukaemia, but normal results were obtained in cases of chronic granulocytic leukaemia, myelosclerosis, solid lymphomas and in acute leukaemias in remission. In relapsed acute leukaemia, fluorescence polarization indicated reduced "microviscosity" of the cell membrane when large numbers (greater than 10(9)/1) of primitive cells were present; normal "microviscosity" was indicated when less than 10(9)/1 primitive cells were present. However, exceptions occurred in both cases, and the technique failed to give warning of imminent relapse in one case. Our findings suggest that a reduction in "microviscosity" as indicated by this technique is not a general property of the blood leucocytes in all types of leukaemia, and that the technique cannot, at present, be regarded as an alternative method for detecting circulating primitive cells.

Comparison of uridine uptake at 24 hours with thymidine uptake at 72 hours in phytohaemagglutinin-stimulated cultures of pregnant and other subjects.

As a possible more rapid test of lymphocyte reactivity to phytohaemagglutinin (PHA) than the standard estimation of thymidine uptake after 72 hours (T72), uridine uptake after 24 hours (U24) was studied in a total of 96 individuals. No reliable correlation between the two estimations was found in 29 outpatients showing a wide range of reactivity to PHA nor in 30 healthy control subjects nor in 16 pregnant subjects. Conflicting reports have appeared in the literature as to whether lymphocyte reactivity to PHA is normal, depressed or enhanced in pregnancy. Our group of pregnant subjects showed a significant depression of both U24 (P less than 0-01) and T72 (P less than 0-02) results as compared to normal female controls. Cultures of semipurified lymphocytes prepared by gradient centrifugation on a further 21 normal control subjects showed no better correlation between U24 and T72 results than the above unpurified-leucocyte cultures.