RESUMEN
In 2012, the International Council for Standardization in Hematology (ICSH) published recommendations for the identification, quantitation, and diagnostic value of schistocytes. In the present review, the impact of these recommendations is evaluated. This work is based on citations in peer-reviewed papers published since 2012. The first 2012 ICSH Recommendations have also been revised to incorporate newly published data in the literature and current best laboratory practice. Recommended reference ranges have been proposed for healthy adults and full-term neonates of 1% or less schistocytes. More than 1% of morphologically identified schistocytes on the blood film are considered suspicious for thrombotic microangiopathy. For preterm infants, a normal level of 5% or less is recommended. The fragment red cell count (FRC) generated by some automated hematological analyzers provides a valuable screening tool for the presence of schistocytes. Specifically, the absence of FRCs can be used as a valuable parameter to exclude the presence of schistocytes on the blood film. The validity and usefulness of microscope schistocytes and automated FRCs, respectively, are discussed in the context of the laboratory diagnostic tests used for thrombotic microangiopathies.
Asunto(s)
Eritrocitos/patología , Microangiopatías Trombóticas/diagnóstico , Adulto , Recuento de Eritrocitos , Humanos , Recién Nacido , Recien Nacido Prematuro , Valores de Referencia , Microangiopatías Trombóticas/sangre , Microangiopatías Trombóticas/patologíaAsunto(s)
Leucemia Mieloide Aguda/complicaciones , Enfermedad de Wolman/complicaciones , Adulto , Médula Ósea/patología , Femenino , Humanos , Cariotipo , Leucemia Mieloide Aguda/diagnóstico , Leucemia Mieloide Aguda/genética , Leucemia Mieloide Aguda/patología , Mutación Puntual , Enfermedad de Wolman/diagnóstico , Enfermedad de Wolman/genética , Enfermedad de Wolman/patología , Enfermedad de WolmanRESUMEN
INTRODUCTION: Morphological assessment of the blood smear has been performed by conventional manual microscopy for many decades. Recently, rapid progress in digital imaging and information technology has led to the development of automated methods of digital morphological analysis of blood smears. METHODS: A panel of experts in laboratory hematology reviewed the literature on the use of digital imaging and other strategies for the morphological analysis of blood smears. The strengths and weaknesses of digital imaging were determined, and recommendations on improvement were proposed. RESULTS: By preclassifying cells using artificial intelligence algorithms, digital image analysis automates the blood smear review process and enables faster slide reviews. Digital image analyzers also allow remote networked laboratories to transfer images rapidly to a central laboratory for review, and facilitate a variety of essential work functions in laboratory hematology such as consultations, digital image archival, libraries, quality assurance, competency assessment, education, and training. Different instruments from several manufacturers are available, but there is a lack of standardization of staining methods, optical magnifications, color and display characteristics, hardware, software, and file formats. CONCLUSION: In order to realize the full potential of Digital Morphology Hematology Analyzers, pre-analytic, analytic, and postanalytic parameters should be standardized. Manufacturers of new instruments should focus on improving the accuracy of cell preclassifications, and the automated recognition and classification of pathological cell types. Cutoffs for grading morphological abnormalities should depend on clinical significance. With all current devices, a skilled morphologist remains essential for cell reclassification and diagnostic interpretation of the blood smear.
Asunto(s)
Hematología , Procesamiento de Imagen Asistido por Computador , Microscopía , Programas Informáticos , HumanosAsunto(s)
Células Precursoras de Granulocitos/patología , Leucemia Promielocítica Aguda/diagnóstico , Anciano de 80 o más Años , Antígenos CD/análisis , Antineoplásicos/uso terapéutico , Trióxido de Arsénico/uso terapéutico , Células Precursoras de Granulocitos/efectos de los fármacos , Humanos , Leucemia Promielocítica Aguda/sangre , Leucemia Promielocítica Aguda/tratamiento farmacológico , Leucemia Promielocítica Aguda/patología , Masculino , Megacariocitos/patología , Tretinoina/uso terapéuticoRESUMEN
BACKGROUND: In transfusion-dependent anaemias, while absolute serum ferritin levels broadly correlate with liver iron concentration (LIC), relationships between trends in these variables are unclear. These relationships are important because serum ferritin changes are often used to adjust or switch chelation regimens when liver magnetic resonance imaging (MRI) is unavailable. OBJECTIVES AND METHODS: This post hoc analysis of the EPIC study compared serum ferritin and LIC in 317 patients with transfusion-dependent thalassaemia before and after 1 yr of deferasirox. RESULTS: Serum ferritin responses (decreases) occurred in 73% of patients, 80% of whom also have decreased LIC. However, 52% of patients without a serum ferritin response did decrease LIC and by >1 mg Fe/g dw (median 3.9) in 77% of cases. Absolute serum ferritin and LIC values correlated significantly only when serum ferritin was <4000 ng/mL (r = 0.59; P < 0.0001) and not at higher levels (≥4000 ng/mL; r = 0.19). Serum ferritin response was accompanied by decreased LIC in 89% and 70% of cases when serum ferritin was <4000 or ≥4000 ng/mL, respectively. CONCLUSIONS: As serum ferritin non-response was associated with LIC decrease in over half of patients, use of liver MRI may be particularly useful for differentiating true from apparent non-responders to deferasirox based on serum ferritin trends alone.
Asunto(s)
Benzoatos/uso terapéutico , Ferritinas/sangre , Quelantes del Hierro/uso terapéutico , Sobrecarga de Hierro/tratamiento farmacológico , Sobrecarga de Hierro/etiología , Hierro/metabolismo , Hígado/metabolismo , Talasemia/sangre , Talasemia/complicaciones , Triazoles/uso terapéutico , Adolescente , Adulto , Biomarcadores , Terapia por Quelación , Niño , Preescolar , Deferasirox , Femenino , Humanos , Sobrecarga de Hierro/diagnóstico , Masculino , Persona de Mediana Edad , Pronóstico , Curva ROC , Talasemia/terapia , Reacción a la Transfusión , Resultado del Tratamiento , Adulto JovenRESUMEN
AIMS: To correlate the presence or absence of a factor XI gene mutation with factor XI activity in patients with severe or partial reduction in factor XI. METHODS: Patients previously found to have reduced factor XI levels were recalled for repeat testing and factor XI genetic analysis. Also, during the 18 month study period, any routine patient found to have an isolated reduced or low normal factor XI level had factor XI genetic analysis. RESULTS: Twenty-two cases were studied and 11 with factor XI from <2 to 57 U/dL (reference 55-130 U/dL), were found to have a factor XI gene mutation. Gene sequencing identified 15 different mutations, with four patients found to be compound heterozygotes. One patient with no bleeding history had a novel polymorphism which family studies showed was not associated with his low factor XI. No factor XI gene abnormality was detected in 10 patients and they have either acquired causes of deficiency or factor XI levels in the lower portion of the normal range. CONCLUSION: Genetic analysis of the factor XI gene is important to confirm or exclude inherited causes of factor XI deficiency, especially when the reduction is mild.
Asunto(s)
Análisis Mutacional de ADN/métodos , Deficiencia del Factor XI/diagnóstico , Deficiencia del Factor XI/genética , Factor XI/genética , Mutación , Adulto , Anciano , Anciano de 80 o más Años , Coagulación Sanguínea , Niño , Deficiencia del Factor XI/sangre , Femenino , Tamización de Portadores Genéticos , Pruebas Genéticas , Heterocigoto , Humanos , Masculino , Valores de Referencia , Australia del SurRESUMEN
Patients with hematologic malignancies have increased risks of thromboembolism or bleeding. The commonest thrombotic complication is venous thromboembolism (VTE). Other thrombotic conditions occur in association with specific disorders, such as thrombotic thrombocytopenic purpura in hematopoietic stem cell transplantation and disseminated intravascular coagulation in acute promyelocytic leukemia. Clinical trials show that unfractionated heparin (UFH) and low molecular weight heparin (LMWH) are efficacious for VTE prophylaxis in cancer patients after major surgery or when hospitalized for acute medical illnesses. These findings in cancer patients are probably applicable to patients with hematologic malignancies, in whom there are very few studies. However, the effectiveness of anticoagulant VTE prophylaxis is not established in ambulatory patients with cancer except for multiple myeloma patients treated with thalidomide and chemotherapy. LMWH is widely used as initial treatment for VTE because it enables home therapy without laboratory monitoring, thereby improving the patient's quality of life. UFH is preferred in patients with high bleeding risks and renal impairment. In cancer patients, vitamin K antagonists for the long-term treatment of VTE are increasingly replaced by LMWH, which show superior efficacy. When prescribing anticoagulant prophylaxis or treatment to patients with hematologic malignancies, clinical benefits must be weighed carefully against the risks of bleeding.
Asunto(s)
Neoplasias Hematológicas/complicaciones , Tromboembolia/terapia , Anticoagulantes/uso terapéutico , Manejo de la Enfermedad , Hemorragia/etiología , Heparina de Bajo-Peso-Molecular/uso terapéutico , Humanos , Premedicación , Medición de Riesgo , Tromboembolia/etiologíaRESUMEN
BACKGROUND: Animal studies suggest that cell transplantation, including bone marrow-derived cells, can ameliorate left ventricular remodeling following myocardial ischemia. Clinical evaluation of the potential benefits of this approach is limited by the lack of safety and feasibility studies. We have assessed the safety and feasibility of intramyocardial transplantation of autologous bone marrow-derived cells in patients undergoing coronary artery bypass graft (CABG) surgery. METHODS AND RESULTS: Between December 2001 and May 2002 7 patients, scheduled for CABG, consented to the trial. All had CABG using hypothermic cardiopulmonary bypass (CPB) and cold cardioplegic arrest. An average of 21 10(6) (8.6 10(6) to 35.1 10(6)) nucleated cells, and 4.2 10(4) (2.5 10(4) to 8.1 10(4)) CD34+ cells were injected into the anterior-lateral wall of the left ventricle, after discontinuation of cardiopulmonary bypass. The end points to assess safety included death, massive bleeding, electrocardiographic or biochemical evidence of myocardial infarction, ventricular dysrhythmia, myocardial perfusion, ventricular function, and the patients' functional status. All patients recovered well without ventricular arrhythmia, bleeding, or other major peri-operative complications. The average intensive care unit (ICU) and hospital stay was 1 and 7 days, respectively. Repeat Technetium-99m myocardial perfusion stress imaging and echocardiography 6 weeks after surgery showed improvement in tissue perfusion, and an average improvement of left ventricular function of 13.5% +/- 11.54% (the mean pre- and post-operative left ventricular EF were 32.5% +/- 15.46% and 46% +/- 18.55%, respectively). Twenty-four hours Holter monitoring showed no significant arrhythmia, 3 months post-operatively. All patients with narrow QRS complex showed no evidence of late potential, on signal-averaged electrocardiogram. At 4 to 9 months after surgery patients were in NYHA functional class "I". CONCLUSIONS: This early clinical experience shows that autologous bone marrow-derived cell transplantation into myocardium is feasible and relatively safe. Further clinical trials to assess the role of cell transplantation for myocardial repair are required.
Asunto(s)
Trasplante de Médula Ósea , Puente de Arteria Coronaria , Enfermedad Coronaria/cirugía , Anciano , Trasplante de Médula Ósea/efectos adversos , Circulación Coronaria , Enfermedad Coronaria/diagnóstico , Enfermedad Coronaria/fisiopatología , Ecocardiografía , Electrocardiografía , Electrocardiografía Ambulatoria , Estudios de Factibilidad , Corazón/diagnóstico por imagen , Humanos , Persona de Mediana Edad , Periodo Posoperatorio , Cintigrafía , Tecnecio , Trasplante Autólogo , Resultado del Tratamiento , Función Ventricular IzquierdaRESUMEN
Virtual microscopy is the simulation of microscopy over a computer network. A virtual slide is a giant digital image file of a glass slide that can be displayed, panned, zoomed, and focused in a virtual slide viewer on a computer screen. Virtual slides represent a revolutionary advance over glass slides. They are easy to file, store, retrieve, annotate, and mark and can be preserved indefinitely. Furthermore, they are easy to duplicate and distribute and can be integrated into electronic patient records. Large virtual slides can be readily transmitted to users over a standard broadband connection. With the recent introduction of viewers that can focus virtual slides, virtual microscopy can simulate all the functions of real microscopy. Virtual microscopy has significant advantages over real microscopy in education and in proficiency testing. In education, virtual microscopy enables "anytime, anywhere" learning and has been favorably received by students and teachers. In proficiency surveys, all users view the same image, virtual slides are easy to distribute, and the slides do not deteriorate. Potential applications for hematology proficiency surveys include blood and bone marrow morphology, differential cell counts, cytochemistry and immunocytochemistry, detection of malarial parasites, and other tests. Virtual microscopy enables proficiency surveys of critical clinical parameters, such as the bone marrow blast count, and implementation of "locate and identify" exercises. It is conceivable that with the next generation of technological developments, virtual microscopy can be extended to diagnostic applications. Important goals are to minimize slide file size without loss of relevant detail, to establish diagnostic equivalence, and to automate virtual slide capture with high throughput for integration into laboratory information systems. Key factors that will drive implementation include user-friendliness, cost, data storage requirements, and throughput speed. Implementation may have constructive effects on teaching and learning, the peer-to-peer consultative process, and diagnostic accuracy and performance.
Asunto(s)
Hematología/métodos , Interfaz Usuario-Computador , Hematología/tendencias , Humanos , Procesamiento de Imagen Asistido por Computador , Programas InformáticosRESUMEN
Human DCs (dendritic cells) express surface CD83 upon activation. Comparing the surface induction of CD83 with the upregulation of CD40, CD80 and CD86 during LPS (lipopolysaccharide)-induced DC maturation showed that CD83 induction occurred more rapidly. Despite the lack of CD83 on immature DCs, it was detected in these cells by Western blotting and flow cytometry. Indirect immunofluorescence revealed CD83 inside immature DCs in perinuclear regions. CD83 was absent on monocytes and macrophages, but it was detected inside these cells and found to be rapidly surface-expressed upon LPS-induced activation. Whereas CD83 expression on activated DCs was sustainable, its expression on monocytes and macrophages was transient. Optimal interleukin-4 co-stimulation during DC generation from monocytes was found to be essential for stable CD83 surface expression. CD83 was detected as 37 and 50 kDa forms in transfected 293T cells. Macrophages and immature DCs expressed the 37 kDa form, whereas mature DCs predominantly expressed the 50 kDa form. In monocytes, CD83 was detected as a 22 kDa detergent-insoluble form. The rapid CD83 surface induction on DCs and macrophages was blocked by brefeldin A, but not by cycloheximide, showing that fresh CD83 synthesis was not essential. Tunicamycin inhibited the expression of the 50 and 37 kDa CD83 forms, and also blocked CD83 surface expression on DCs and macrophages. PNGase F (peptide N-glycosidase F) digestion reduced the 37 and 50 kDa CD83 forms to 28 kDa. In summary, monocytes, macrophages and immature DCs contain preformed intracellular CD83, and its rapid surface expression upon activation is post-translationally regulated in a process involving glycosylation.
Asunto(s)
Diferenciación Celular , Células Dendríticas/citología , Células Dendríticas/metabolismo , Regulación de la Expresión Génica , Inmunoglobulinas/metabolismo , Macrófagos/metabolismo , Glicoproteínas de Membrana/metabolismo , Monocitos/metabolismo , Antígenos CD/metabolismo , Diferenciación Celular/efectos de los fármacos , Membrana Celular/efectos de los fármacos , Membrana Celular/metabolismo , Núcleo Celular/efectos de los fármacos , Núcleo Celular/metabolismo , Células Cultivadas , Células Dendríticas/efectos de los fármacos , Detergentes/farmacología , Regulación de la Expresión Génica/efectos de los fármacos , Glicosilación , Humanos , Inmunoglobulinas/química , Interleucina-4/farmacología , Espacio Intracelular/efectos de los fármacos , Espacio Intracelular/metabolismo , Lipopolisacáridos/farmacología , Macrófagos/citología , Macrófagos/efectos de los fármacos , Glicoproteínas de Membrana/química , Peso Molecular , Monocitos/citología , Monocitos/efectos de los fármacos , Transporte de Proteínas/efectos de los fármacos , Solubilidad , Regulación hacia Arriba/efectos de los fármacos , Antígeno CD83RESUMEN
Siglecs are sialic acid binding Ig-like lectins mostly expressed in the haemopoietic and immune systems. Amongst the 11 human siglecs, there are eight proteins highly related to CD33 which have biochemical features of inhibitory receptors, containing two conserved tyrosine-based inhibitory motifs. Five of these (CD33/siglec-3, -5, -7, -9 and -10) are expressed on circulating monocytes. Here we show that monocytes cultured to differentiate into macrophages using either GM-CSF or M-CSF retained expression of these siglecs and their levels were unaffected following stimulation with LPS. In comparison, monocyte-derived dendritic cells down-modulated siglec-7 and -9 following maturation with LPS. Plasmacytoid dendritic cells in human blood expressed siglec-5 only. On monocytes, siglec-5 was shown to mediate rapid uptake of anti-siglec-5 (Fab)2 fragments into early endosomes. This suggests, in addition to inhibitory signalling, a potential role in endocytosis for siglec-5 and the other CD33-related siglecs. Our results show that siglecs are differentially expressed on mononuclear phagocytes and dendritic cells and that some can be modulated by stimuli that promote maturation and differentiation.
Asunto(s)
Antígenos CD/metabolismo , Antígenos de Diferenciación Mielomonocítica/metabolismo , Células Dendríticas/metabolismo , Lectinas/metabolismo , Macrófagos/metabolismo , Monocitos/citología , Fagocitos/metabolismo , Antígenos CD/sangre , Antígenos de Diferenciación Mielomonocítica/sangre , Diferenciación Celular , Citometría de Flujo , Humanos , Modelos Biológicos , Lectina 3 Similar a Ig de Unión al Ácido Siálico , Lectinas Similares a la Inmunoglobulina de Unión a Ácido SiálicoRESUMEN
Cold agglutinin disease (CAD) is a hemolytic anemia due to anti-red cell autoantibodies that are reactive at cold temperatures. In the elderly, it may be associated with underlying B-cell lymphoma, usually a lympho-plasmacytic lymphoma variant. We report a case of CAD in an elderly Indonesian female, which was associated with a B-cell lymphoma that showed a histologic appearance consistent with large-cell lymphoma. Cytogenetic analysis revealed the presence of trisomies 3 and 12, which have been reported previously in B-cell lymphoma associated with CAD. In addition, a t(8;22) was found in 24 out of 28 metaphases. Translocation (8;22) is associated with Burkitt lymphoma or acute lymphoblastic lymphoma, French-American-British subtype L3. It has not been previously reported in B-cell lymphoma asssociated with CAD, and could represent a blastic transformation of the underlying B-cell lymphoma.
Asunto(s)
Anemia Hemolítica Autoinmune/genética , Aberraciones Cromosómicas , Cromosomas Humanos Par 22/genética , Cromosomas Humanos Par 8/genética , Linfoma de Células B/genética , Translocación Genética/genética , Anciano , Linfoma de Burkitt/genética , Análisis Citogenético/métodos , Femenino , Humanos , Linfoma de Células B Grandes Difuso/genéticaRESUMEN
OBJECTIVE: Hyperdiploidy of 51-65 chromosomes is associated with a good prognosis in childhood B-lineage acute lymphoblastic leukemia (ALL). Blasts from childhood ALL patients with a hyperdiploid karyotype have a tendency to apoptosis when cultured on stromal layers in vitro. In this study, we apply a novel method to investigate the relationship between apoptosis and hyperdiploidy in lymphoblasts of childhood ALL. MATERIALS AND METHODS: The DNA content of individual ALL blasts in Feulgen-stained archival bone marrow smears can be determined by static cytometry. TUNEL (TdT-mediated dUTP-biotin nick end labeling) detects the DNA degradation associated with apoptosis. We performed TUNEL in situ sequential to DNA ploidy analysis in archival bone marrow smears from 12 patients with childhood ALL. RESULTS: Five patients were diploid and seven were hyperdiploid (51-65 chromosomes) by conventional cytogenetic analysis. In the five diploid cases, the percentage of TUNEL-positive blasts ranged from 1.0% to 1.3%; in the seven hyperdiploid cases, the percentage of TUNEL-positive blasts ranged from 3.6% to 9.0%. Comparing TUNEL and corresponding Feulgen images, we found that apoptotic blasts were predominantly of high DNA ploidy in both diploid and hyperdiploid cases. The mean DNA value of apoptotic blasts was larger than that of the total blast population in each case. CONCLUSIONS: The results demonstrate an increased incidence of spontaneous apoptosis in situ of hyperdiploid blasts in ALL bone marrow and indicate that this phenomenon is not restricted to in vitro cultures. The findings provide a possible rationale for the good prognosis associated with hyperdiploid childhood ALL.
Asunto(s)
Apoptosis/genética , Médula Ósea/patología , Ploidias , Leucemia-Linfoma Linfoblástico de Células Precursoras/patología , Apoptosis/fisiología , Linfoma de Burkitt/genética , Linfoma de Burkitt/patología , Preescolar , Análisis Citogenético , Diploidia , Femenino , Humanos , Etiquetado Corte-Fin in Situ , Incidencia , Lactante , Masculino , Leucemia-Linfoma Linfoblástico de Células Precursoras/genética , PronósticoRESUMEN
Medical laboratories in Singapore subscribe to External Quality Assurance Schemes run by the Licensing and Accreditation Unit of the Ministry of Health, Singapore, as well as a number of foreign medical laboratory quality assurance institutions. Through these organisations, a comprehensive range of laboratory tests are externally monitored for quality assurance at regular intervals in all medical laboratories. In recent years, an increasing number of local quality assurance schemes have been implemented, and an increasing number of laboratories have gained accreditation by foreign quality assurance institutions. The respective roles of these quality assurance activities are discussed.