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2.
Int J Lab Hematol ; 37(3): 304-25, 2015 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-25790109

RESUMO

INTRODUCTION: Hereditary spherocytosis (HS), hereditary elliptocytosis (HE), and hereditary stomatocytosis (HSt) are inherited red cell disorders caused by defects in various membrane proteins. The heterogeneous clinical presentation, biochemical and genetic abnormalities in HS and HE have been well documented. The need to raise the awareness of HSt, albeit its much lower prevalence than HS, is due to the undesirable outcome of splenectomy in these patients. METHODS: The scope of this guideline is to identify the characteristic clinical features, the red cell parameters (including red cell morphology) for these red cell disorders associated, respectively, with defective cytoskeleton (HS and HE) and abnormal cation permeability in the lipid bilayer (HSt) of the red cell. The current screening tests for HS are described, and their limitations are highlighted. RESULTS: An appropriate diagnosis can often be made when the screening test result(s) is reviewed together with the patient's clinical/family history, blood count results, reticulocyte count, red cell morphology, and chemistry results. SDS-polyacrylamide gel electrophoresis of erythrocyte membrane proteins, monovalent cation flux measurement, and molecular analysis of membrane protein genes are specialist tests for further investigation. CONCLUSION: Specialist tests provide additional evidence in supporting the diagnosis and that will facilitate the management of the patient. In the case of a patient's clinical phenotype being more severe than the affected members within the immediate family, molecular testing of all family members is useful for confirming the diagnosis and allows an insight into the molecular basis of the abnormality such as a recessive mode of inheritance or a de novo mutation.


Assuntos
Anemia Hemolítica Congênita/diagnóstico , Anemia Hemolítica Congênita/etiologia , Membrana Eritrocítica/metabolismo , Anemia Hemolítica Congênita/complicações , Eliptocitose Hereditária/diagnóstico , Membrana Eritrocítica/química , Humanos , Esferocitose Hereditária/diagnóstico
3.
Int J Lab Hematol ; 34(6): 594-604, 2012 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-22713122

RESUMO

INTRODUCTION: High-performance liquid chromatography (HPLC) is a method commonly used for the detection of hemoglobin (Hb) variants. In addition to providing precise quantitation of Hb A2 and Hb F, the reported retention time and peak shape of a high number of hemoglobin (Hb) variants are very helpful for presumptive identification. However, there is a scarcity of summarized data in the literature of the mobility of Hb variants on this method. METHODS: A total of 383 Hb variants were studied on the Bio-Rad Variant (™) Classic HPLC instrument. Hb variant identification used a number of methods, including confirmation by DNA sequencing in at least one case for all alpha and beta chain Hb variants. RESULTS: Retention time data and the number of occurrences of each Hb variant were obtained. This showed that rare Hb variants can have similar retention times to the five most common alpha or beta chain Hb variants. CONCLUSION: HPLC is a very powerful tool in the evaluation of Hb variants, particularly when combined with other methods. However, it should not be used as a stand-alone method for definitive identification of Hb variants.


Assuntos
Cromatografia Líquida de Alta Pressão/métodos , Hemoglobinas Anormais/análise , alfa-Globinas/análise , Globinas beta/análise , Variação Genética , Hemoglobinas Anormais/genética , Humanos , Reprodutibilidade dos Testes , Análise de Sequência de DNA , alfa-Globinas/genética , Globinas beta/genética
4.
Int J Lab Hematol ; 34(1): 14-20, 2012 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-21914140

RESUMO

Measurement of the Haemoglobin F in red cell haemolysates is important in the diagnosis of 뫧 thalassaemia, hereditary persistence of fetal haemoglobin (HPFH) and in the diagnosis and management of sickle cell disease. The distribution of Hb F in red cells is useful in the diagnosis of HPFH and in the assessment of feto-maternal haemorrhage. The methods of quantifying Hb F are described together with pitfalls in undertaking these laboratory tests with particular emphasis on automated high-performance liquid chromatography and capillary electrophoresis.


Assuntos
Hemoglobina Fetal/análise , Talassemia/diagnóstico , Álcalis , Cromatografia Líquida de Alta Pressão/métodos , Eletroforese Capilar/métodos , Citometria de Fluxo/métodos , Humanos , Imunodifusão/métodos , Desnaturação Proteica , Reprodutibilidade dos Testes , Sensibilidade e Especificidade , Manejo de Espécimes/métodos
5.
Int J Lab Hematol ; 34(1): 1-13, 2012 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-21974826

RESUMO

Although DNA analysis is needed for characterization of the mutations that cause ß-thalassaemia, measurement of the Hb A(2) is essential for the routine identification of people who are carriers of ß-thalassaemia. The methods of quantitating Hb A(2) are described together with pitfalls in undertaking these laboratory tests with particular emphasis on automated high-performance liquid chromatography and capillary electrophoresis.


Assuntos
Hemoglobina A2/análise , Talassemia beta/diagnóstico , Cromatografia Líquida de Alta Pressão/métodos , Eletroforese Capilar , Heterozigoto , Humanos , Valores de Referência , Reprodutibilidade dos Testes , Sensibilidade e Especificidade , Manejo de Espécimes/métodos , Terminologia como Assunto , Talassemia beta/genética
7.
Leukemia ; 24(7): 1283-9, 2010 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-20485371

RESUMO

The 2008 World Health Organization (WHO) criteria were used to identify 88 consecutive Mayo Clinic patients with 'myelodysplastic syndrome with isolated del(5q)' (median age 74 years; 60 females). In all, 60 (68%) patients were followed up to the time of their death. Overall median survival was 66 months; leukemic transformation was documented in five (5.7%) cases. Multivariable analysis identified age >or=70 years (P=0.01), transfusion need at diagnosis (P=0.04) and dysgranulopoiesis (P=0.02) as independent predictors of shortened survival; the presence of zero (low risk), one (intermediate risk) or >or=2 (high risk) risk factors corresponded to median survivals of 102, 52 and 27 months, respectively. Janus kinase 2 (JAK2), thrombopoietin receptor (MPL), isocitrate dehydrogenase 1 (IDH1) and IDH2 mutational analysis was performed on archived bone marrows in 78 patients; JAK2V617F and MPLW515L mutations were shown in five (6.4%) and three (3.8%) patients, respectively, and did not seem to affect phenotype or prognosis. IDH mutations were not detected. Survival was not affected by serum ferritin and there were no instances of death directly related to iron overload. The current study is unique in its strict adherence to WHO criteria for selecting study patients and providing information on long-term survival, practical prognostic factors, baseline risk of leukemic transformation and the prevalence of JAK2, MPL and IDH mutations.


Assuntos
Cromossomos Humanos Par 5/genética , Isocitrato Desidrogenase/genética , Janus Quinase 2/genética , Mutação/genética , Síndromes Mielodisplásicas/genética , Receptores de Trombopoetina/genética , Adulto , Idoso , Idoso de 80 Anos ou mais , Transformação Celular Neoplásica , Deleção Cromossômica , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Síndromes Mielodisplásicas/mortalidade , Síndromes Mielodisplásicas/patologia , Reação em Cadeia da Polimerase , Prognóstico , Taxa de Sobrevida , Organização Mundial da Saúde
8.
Int J Lab Hematol ; 32(3): 307-11, 2010 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-19765111

RESUMO

Laboratory identification of hemoglobin (Hb) variants can involve multiple techniques. The use of semi-automated instruments that perform gel electrophoresis and staining, such as the SPIFE 3000 electrophoresis system, can greatly reduce the labor required for these commonly used techniques. We performed a comparison of the method involved in SPIFE 3000 system with those of manual gel electrophoresis. A total of 22 540 samples were analyzed using the SPIFE 3000, and compared with mobilities on cellulose acetate and citrate agar gels using standard manual methods. The results were compared using relative electrophoretic mobilities (REM). Of the 191 Hb variants identified, only 13 had REM that differed from manual electrophoresis when analyzed using the SPIFE 3000 system. One variant (Hb O-Indonesia) showed different mobility on both acid and alkaline gels, two (Hb E, Hb Sunshine Seth) on alkaline gel only, and 10 (Hbs N-Baltimore, N-Seattle, O-Arab, Shelby, Summer Hill, Tak, Hasharon, M-Iwate, Q-Iran, and Setif) on acid gels only. The SPIFE 3000 semi-automated electrophoresis system produces similar results when compared with those of standard manual electrophoresis methods.


Assuntos
Eletroforese/instrumentação , Eletroforese/métodos , Hemoglobinas/análise , Variação Genética , Humanos
10.
Br J Haematol ; 130(1): 36-42, 2005 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-15982342

RESUMO

Translocations involving IGH are common in some lymphoid malignancies but are believed to be rare in chronic lymphocytic leukaemia (CLL). To study the clinical utility of fluorescence in situ hybridization (FISH) for IGH translocations, we reviewed 1032 patients with a presumptive diagnosis of CLL. Seventy-six (7%) patients had IGH translocations. Pathology and clinical data were available for the 24 patients evaluated at the Mayo Clinic. Ten (42%) patients had IGH/cyclin D1 fusion and were diagnosed with mantle cell lymphoma (MCL). The immunophenotype was typical of MCL in three of these patients and atypical for MCL in seven patients. One patient had biclonal disease with typical MCL and CLL with IGH/BCL-2. Eleven (46%) patients had IGH/BCL-2 fusion including the patient with biclonal disease. Two of these patients had leukaemic phase follicular lymphoma and nine patients had CLL. The median progression-free survival of patients with CLL and IGH/BCL-2 translocation was 20.6 months. The two patients with IGH/BCL-3 fusion (one of these also had IGH/BCL-11a) had rapid disease progression. The IGH partner gene was not identified in two patients. We conclude that use of an IGH probe in FISH analysis of monoclonal B-cell lymphocytosis improves diagnostic precision and could have prognostic value in patients with CLL.


Assuntos
Genes de Imunoglobulinas , Cadeias Pesadas de Imunoglobulinas/genética , Interfase , Leucemia Linfocítica Crônica de Células B/diagnóstico , Sondas de Oligonucleotídeos , Translocação Genética , Proteína 3 do Linfoma de Células B , Ciclina D1/genética , Diagnóstico Diferencial , Citometria de Fluxo , Genes bcl-2 , Humanos , Imunofenotipagem , Hibridização in Situ Fluorescente , Leucemia Linfocítica Crônica de Células B/genética , Leucemia Linfocítica Crônica de Células B/imunologia , Linfoma de Células B/diagnóstico , Linfoma de Células B/genética , Linfoma de Célula do Manto/diagnóstico , Linfoma de Célula do Manto/genética , Proteínas Proto-Oncogênicas/genética , Fatores de Transcrição
11.
J Clin Pathol ; 57(6): 637-40, 2004 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-15166271

RESUMO

AIMS: To evaluate the technique of multiple displacement amplification (MDA) for whole genome amplification from small volume blood samples before sequencing in a clinical test to identify haemoglobin gene mutations. METHODS: Phage phi29 DNA polymerase was used to perform MDA, starting with either 1 micro l of blood or 1 ng of previously isolated blood DNA from 23 patients. The amplified products were then evaluated using a clinical test that involves sequencing the haemoglobin genes to detect mutations. The results were compared with the current clinical test method that uses genomic DNA isolated using column based technology. RESULTS: The MDA technique produced large quantities (theoretically approximately 2 mg) of DNA. The amplification procedure was extremely easy and took about four hours (less than one hour of hands on technician time and three hours for amplification). When MDA products were used in the same clinical test protocol as genomic DNA isolated using column technology, there was 100% concordance for detection of a variety of point mutations in the alpha1, alpha2, and beta globin genes. CONCLUSIONS: The MDA technique is useful for overcoming the problem of insufficient genomic DNA in clinical specimens requiring haemoglobin gene sequencing and could be useful for other clinical applications.


Assuntos
Globinas/genética , Mutação Puntual , Sequência de Bases , Eletroforese em Gel de Ágar , Genoma Humano , Humanos , Dados de Sequência Molecular , Técnicas de Amplificação de Ácido Nucleico/métodos , Reação em Cadeia da Polimerase/métodos , Estudos Retrospectivos , Análise de Sequência de DNA
12.
Ann Hematol ; 80(3): 166-9, 2001 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-11320902

RESUMO

The absence of stainable iron in a bone marrow aspirate is widely considered to be diagnostic of iron deficiency anemia (IDA). We re-evaluated this concept by studying a cohort of 108 consecutive bone marrow specimens from an unselected series of patients who were seen at a hematology clinic and in whom iron stores were reported as being absent. A review of the pathologic reports revealed 19 inadequate specimens and 15 with decreased, but not absent, iron stores. Thus, only 74 of the 108 cases had been accurately reported. In 37 of these cases, adequate clinical and laboratory data were available and allowed further analysis. In 18 patients, careful review of patient history, physical examination, results of endoscopic procedures, and follow-up information failed to suggest the presence of IDA (group A). The review process in the remaining 19 patients suggested the possibility of IDA (group B). Significant differences between groups A and B were observed in serum ferritin (P = 0.001) and red blood cell mean corpuscular volume (P = 0.004). In contrast, the two groups did not differ significantly in hemoglobin concentration, serum iron, total iron-binding capacity, transferrin saturation, or erythrocyte sedimentation rate. These observations suggest that a pathology report of absent bone marrow hemosiderin may be inaccurate in more than 30% of cases and, even when accurate, may not necessarily signify the presence of IDA. Measurement of the serum ferritin level is needed to confirm a clinical diagnosis.


Assuntos
Anemia Ferropriva/diagnóstico , Medula Óssea/metabolismo , Ferro/metabolismo , Idoso , Anemia Ferropriva/sangue , Exame de Medula Óssea , Feminino , Ferritinas/metabolismo , Hemossiderina/metabolismo , Humanos , Masculino , Pessoa de Meia-Idade
13.
Mayo Clin Proc ; 76(3): 285-93, 2001 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-11243275

RESUMO

Hereditary disorders of erythrocytes are common in many areas of the world, including the Middle East. In some regions of the Middle East more than 10% of the population are carriers of a gene for one of these conditions. When patients from the Middle East seek medical care in the West, an unrecognized but clinically important erythrocyte disorder can result in serious complications during routine medical care, such as a drug-induced hemolytic crisis. This article reviews the most important and most common inherited red blood cell disorders in Middle Eastern patients, including glucose-6-phosphate dehydrogenase deficiency, the thalassemias, and sickle cell disorders. We discuss when to suspect such conditions, how to determine their presence, and how to avoid potential complications related to them. Although a detailed discussion of treatment of erythrocyte disorders is beyond the scope of this article, some general management principles are described.


Assuntos
Anemia Hemolítica Congênita/epidemiologia , Anemia Hemolítica Congênita/genética , Anemia Falciforme/epidemiologia , Anemia Falciforme/genética , Eritrócitos Anormais , Deficiência de Glucosefosfato Desidrogenase/epidemiologia , Deficiência de Glucosefosfato Desidrogenase/genética , Humanos , Oriente Médio/epidemiologia , Oriente Médio/etnologia , Talassemia/epidemiologia , Talassemia/genética
14.
Hemoglobin ; 25(4): 375-82, 2001 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-11791870

RESUMO

We report a novel mutation at alpha66(E15)Leu-->Pro (alpha2) (CTG-->CCG), that we have named Hb Dartmouth for the medical center at which the patients were cared for, in monozygotic twins who also inherited the Southeast Asian alpha-thalassemia-1 deletion. The mother, of Khmer ancestry, is heterozygous for alpha-thalassemia-1. The father, who is of Scottish-Irish ancestry, is a silent carrier of the codon 66 mutation. The twins had severe neonatal anemia requiring transfusion.


Assuntos
Anemia Neonatal/genética , Hemoglobinas Anormais/genética , Talassemia alfa/genética , Adulto , Substituição de Aminoácidos , Anemia Neonatal/etiologia , Camboja/etnologia , Análise Mutacional de DNA , Saúde da Família , Feminino , Hemoglobinas Anormais/efeitos adversos , Humanos , Recém-Nascido , Masculino , Mutação Puntual , Gêmeos , Reino Unido/etnologia
15.
Am J Clin Pathol ; 113(6): 831-7, 2000 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-10874884

RESUMO

We identified 24 cases of multiple myeloma with the t(11;14)(q13;q32). In 22 cases, the t(11;14)(q13;q32) was part of a complex karyotype, and in 2 cases it was an isolated abnormality. All patients had clinical and laboratory features consistent with multiple myeloma. The median degree of plasma cell involvement in the bone marrow was 60%, and in 10 cases, the plasma cells had a lymphoplasmacytoid appearance. Of the 24 cases, 21 had intermediate or high proliferative rates based on labeling index studies. Immunohistochemical studies performed on all bone marrow biopsy specimens showed strong cyclin D1 nuclear positivity in 19 cases. There also was strong cyclin D1 nuclear positivity found in 6 of 30 additional cases without the t(11;14)(q13;q32) demonstrated by routine cytogenetics. The t(11;14)(q13;q32) in multiple myeloma results in overexpression of the cyclin D1 protein, which can be demonstrated by immunohistochemical stain. The cyclin D1 stain results in the additional cases of multiple myeloma suggest that the t(11;14)(q13;q32) may be more common than previously thought and may be missed by routine cytogenetics, particularly if the proliferative rate is low.


Assuntos
Cromossomos Humanos Par 11 , Cromossomos Humanos Par 14 , Mieloma Múltiplo/genética , Translocação Genética/genética , Adulto , Idoso , Ciclina D1/metabolismo , Feminino , Humanos , Técnicas Imunoenzimáticas , Masculino , Pessoa de Meia-Idade , Mieloma Múltiplo/metabolismo , Mieloma Múltiplo/patologia
16.
Leuk Lymphoma ; 39(3-4): 391-5, 2000 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-11342320

RESUMO

Conventional cytogenetic analysis is limited in the evaluation of plasma cell disorders because, relative to normal hematopoietic elements, plasma cells divide slowly. Moreover, it is difficult to know whether abnormal metaphases originate from malignant plasma cells or myeloid cells harboring other abnormalities. We studied a patient with primary systemic amyloidosis who had previously been treated with an alkylating agent. Bone marrow cells were analyzed by cytoplasmic-immunoglobulin fluorescent staining combined with fluorescent in situ hybridization (cIg-FISH). Both chromosome enumeration probes for chromosome 1 and 7 and loci-specific probes for the short and long arm of chromosome 7 were used. Cytogenetic analysis disclosed the following abnormality: +der(1;7)(q10;p10). On cIg-FISH, the myeloid cells had fusion signals between chromosome enumeration probes for chromosomes 1 and 7, whereas plasma cells had the normal appearance of two pairs of signals. There was a second clone of abnormal myeloid cells with monosomy of chromosome 7. The bone marrow did not show any evidence of myelodysplasia. Interphase cIg-FISH is a useful technique for assigning the lineage of chromosomal abnormalities in plasma cell disorders.


Assuntos
Amiloidose/tratamento farmacológico , Antineoplásicos Alquilantes/efeitos adversos , Células Mieloides/metabolismo , Translocação Genética/genética , Amiloidose/genética , Antineoplásicos Alquilantes/administração & dosagem , Deleção Cromossômica , Cromossomos Humanos Par 1 , Cromossomos Humanos Par 7 , Análise Citogenética , Feminino , Humanos , Hibridização in Situ Fluorescente , Pessoa de Meia-Idade , Monossomia , Células Mieloides/patologia , Plasmócitos/metabolismo
17.
Leuk Lymphoma ; 35(5-6): 599-605, 1999 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-10609798

RESUMO

The most common chromosomal translocation in multiple myeloma (MM) is t(11;14)(q13;q32). Here, we describe the clinical characteristics of patients with MM who have this translocation. We have identified 24 patients at our institution who had t(11;14)(q13;q32) as determined by standard cytogenetic analysis (CC). Seven patients had the translocation detected at the time of original diagnosis and 17 at the time of relapse. Median survival in all patients after original diagnosis was 43 months; median survival after the translocation was detected was 11.9 months. Four patients had a clinical diagnosis of plasma cell leukemia. Most patients had an elevated beta2-microglobulin (13/20 had >4 microg/ml). The bone marrow (BM) labeling index (LI) of patients, at the time of translocation detection, was elevated in most (median 1.4%, 17/23 patients had BMLI > or = 1%). Of the 24 patients, 19 (79%) died of disease progression and 5 (21%) were alive with disease at last follow-up. Lytic lesions, bone pain, or compression fractures eventually developed in all patients. Patients with MM who have t(11;14)(q13;q32) detected by standard cytogenetics seem to have an aggressive clinical course.


Assuntos
Cromossomos Humanos Par 11/ultraestrutura , Cromossomos Humanos Par 14/ultraestrutura , Mieloma Múltiplo/genética , Translocação Genética , Protocolos de Quimioterapia Combinada Antineoplásica/uso terapêutico , Biomarcadores Tumorais/análise , Contagem de Células Sanguíneas , Cálcio/sangue , Cromossomos Humanos Par 11/genética , Cromossomos Humanos Par 14/genética , Creatinina/sangue , Progressão da Doença , Seguimentos , Hemoglobinas/análise , Humanos , Leucemia Plasmocitária/genética , Leucemia Plasmocitária/mortalidade , Leucemia Plasmocitária/patologia , Mieloma Múltiplo/tratamento farmacológico , Mieloma Múltiplo/mortalidade , Mieloma Múltiplo/patologia , Células Neoplásicas Circulantes , Prognóstico , Análise de Sobrevida , Microglobulina beta-2/análise
18.
Blood ; 94(11): 3889-96, 1999 Dec 01.
Artigo em Inglês | MEDLINE | ID: mdl-10572105

RESUMO

This study evaluated the contributing roles of flow cytometric immunophenotyping of blood and bone marrow and immunohistochemical paraffin section staining of bone marrow biopsies in the staging of B-cell malignant lymphoma. Flow immunophenotyping was performed on a marrow specimen in 175 cases; a corresponding blood specimen was also immunophenotyped in 135 of these cases. Morphologic marrow involvement by lymphoma was found in 59 cases; flow immunophenotyping identified 54 cases with a monoclonal B-cell process: morphology-positive/flow-positive (n = 49), morphology-positive/flow-negative (n = 10), morphology-negative/flow-positive (n = 5), and morphology-negative/flow-negative (n = 111). The 10 morphology-positive/flow-negative cases included 5 follicular and 5 large-cell lymphomas with minimal marrow involvement. All 5 morphology-negative/flow-positive cases were from patients with large-cell lymphomas and bulky clinical disease. Because the blood contained the same B-cell clone in 2 of 2 morphology-negative/flow-positive cases studied, blood contamination of marrow may account for these findings. Blood flow cytometric immunophenotyping studies were positive in 32 cases; 30 had marrow involvement by morphology and were from patients with follicular, mantle cell, lymphoplasmacytic, small lymphocytic, or marginal zone lymphomas. From our results, we conclude that (1) bone marrow flow cytometric immunophenotyping is not a cost-effective replacement for good morphologic evaluation in lymphoma staging and that (2) a positive peripheral blood flow cytometric immunophenotyping study when performed in low-grade lymphomas correlates with marrow involvement.


Assuntos
Células Sanguíneas/imunologia , Células da Medula Óssea/imunologia , Imunofenotipagem , Linfoma de Células B/imunologia , Adulto , Idoso , Idoso de 80 Anos ou mais , Células Sanguíneas/patologia , Células da Medula Óssea/patologia , Feminino , Humanos , Linfoma de Células B/patologia , Masculino , Pessoa de Meia-Idade , Estadiamento de Neoplasias
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