Abnormal Lymphocytes (abnormal + lymphocyte)

Distribution by Scientific Domains
Medical Sciences100%

Selected Abstracts

Clonally rearranged T-cell receptor , chain genes in HTLV-I carriers with abnormal, non-flower-like, lymphocytes

EUROPEAN JOURNAL OF HAEMATOLOGY, Issue 4 2005
Maria M. Sales
Abstract:,Background:,The diagnosis of Adult T-cell leukemia/lymphoma ATLL subtypes in human T-lymphotropic virus type I (HTLV-I) carriers based in morphology and immunophenotype of lymphocytes can be challenger. We propose that polymerase chain reaction (PCR) amplification of the rearranged TCR gene in HTLV-I healthy carriers would be a convenient method for establishing the nature of the circulating T lymphocytes in asymptomatic HTLV-I carriers, presenting only mild and inconclusive signals of deviation from normality. Methods:,Using PCR, we analyzed the genetic recombination pattern of the T-cell , -chain receptor gene (TCR - ,) in order to identify clonal expansion of peripheral blood T lymphocytes in 17 HTLV-I-positive healthy carriers and in nine normal HTLV-I-negative blood donors. To evaluate the performance of PCR in detection of clonality, we also analyzed 18 patients with post-thymic/mature T-cell malignancies presenting circulating abnormal lymphocytes. Results:,Seven of the 17 HTLV-I positive individuals presented circulating abnormal lymphocytes; monoclonal or oligoclonal expansion of T-cells was detected in five of the 17 HTLV-I-positive individuals, all of them presenting abnormal lymphocytes. Clonal expansion was not detected in any of the negative controls or in any of the 12 remaining healthy carriers. All patients in the positive control group tested positive by PCR and Southern blots. Southern blots were negative for all 17 healthy carriers. Conclusions:,PCR amplification of segments of rearranged TCR- , is reliable for allowing early detection of small populations of clonal T cells in blood samples from asymptomatic HTLV-I carriers, providing an additional alert in the follow-up of carriers with abnormal circulating lymphocytes. [source]

Quality counts: new parameters in blood cell counting

INTERNATIONAL JOURNAL OF LABORATORY HEMATOLOGY, Issue 3 2009
C. BRIGGS
Summary Recently several parameters have been introduced to the complete blood count such as nucleated red blood cells, immature granulocytes; immature reticulocyte fraction, immature platelet fraction and red cell fragments as well as new parameters for detection of functional iron deficiency. Leucocyte positional parameters, which may diagnose specific diseases (e.g. differentiate between abnormal lymphocytes in leukaemia and viral conditions and may also detect malarial infection) are now available. At this time they are only used for research; however, generally such parameters later become reportable. One manufacturer's routine analyser allows measurement of cells by flow cytometry using monoclonal antibodies. Currently, there are no accredited external quality assessment schemes (EQAS) for these parameters. For a number of parameters, on some instruments, there is no internal quality control, which brings into question whether these parameters should be used for clinical decision making. Other more established parameters, such as mean platelet volume, red cell distribution width and the erythrocyte sedimentation rate do not have EQAS available. The UK National EQAS for General Haematology held a workshop earlier this year in 2008 to discuss these parameters. Participants were asked to provide a consensus opinion on which parameters are the most important for inclusion in future haematology EQAS. [source]

Diagnostic performance of the variant lymphocyte flag of the Abbott Cell-Dyn 4000 haematology analyser

INTERNATIONAL JOURNAL OF LABORATORY HEMATOLOGY, Issue 1 2004
J. J. M. L. Hoffmann
Summary Background: In addition to differential cell counts, modern haematology analysers generate suspect flags if abnormal cells are detected. Reports on validation of suspect flags are scarce. We have routine experience with the Abbott Cell-Dyn 4000 analyser for over 5 years and have previously demonstrated the utility of the blast flag. Here we report a similar study on the performance of the analyser's Variant Lymphocyte (VL) flag. Aim of the study: Evaluation of the diagnostic performance of the Cell-Dyn 4000 VL flag, as compared with lymphocyte morphology in blood smears. In addition, we investigated the usefulness of the numerical VL flag confidence index as provided by the analyser. Materials and methods: All samples generating a VL flag were reviewed over a 5-month period. We also reviewed smears from patients with known lymphoid disorders, even if the analyser did not flag the sample. Two experienced investigators assessed lymphocyte morphology independently. Results: In total, 187 samples were included in the study, of which 183 had a VL flag and four had not. Of the 183 flagged samples, 83 appeared to have abnormal lymphocyte morphology and 100, normal lymphocyte morphology. The sensitivity of the VL flag for detecting abnormal lymphocytes was 0.95 and the positive predictive value was 0.44. Using ROC analysis of the VL flag confidence index, the area under the ROC curve was 0.58 (95% confidence interval 0.50,0.65). Conclusions: The Cell-Dyn VL flag has reasonable sensitivity but a high false-positive rate. In addition, its performance is insufficient for detecting clinically relevant abnormal lymphocytes. As the VL flag appeared to rely mainly on numerical criteria, it has no added value over numerical criteria defined by the laboratory. [source]

Cutaneous T-cell lymphoma

JOURNAL OF THE EUROPEAN ACADEMY OF DERMATOLOGY & VENEREOLOGY, Issue 2 2003
EA Kotz
ABSTRACT Cutaneous T-cell lymphoma (CTCL) is a neoplasm of helper T cells whose first manifestations usually appear in the skin. The various forms of CTCL are distinguished by both clinical features and histopathology. Early on, the diagnosis may be difficult to establish because of its numerous, and often non-specific, clinical presentations. Further, the pathological findings of early lesions may lack the diagnostic features observed in well-developed or advanced disease. The diagnosis of CTCL must be considered in any patient with a chronic, therapy-resistant condition of the skin. In patients with non-specific histological findings, a high index of suspicion and multiple biopsies may eventually lead to a diagnosis of CTCL. Once the diagnosis of CTCL is established, accurate staging is essential both for its effect on treatment decisions and for its prognostic value. In general, CTCL is a chronic, slowly progressive disease with a long evolution. The development of tumours is a poor prognostic sign, as is erythroderma. The Sezary syndrome is a distinct form of erythrodermic CTCL that is characterized by exfoliative erythroderma, lymphadenopathy, lymphocytosis, intense pruritus, and circulating large, abnormal lymphocytes (Sezary cells). When death does occur, it is most often due to septicemia. Treatment of CTCL must be tailored to the individual patient. The most commonly employed treatment options are photochemotherapy and topical chemotherapy. [source]