Deficiencia de glucosa-6-fosfato deshidrogenasa eritrocitaria en Rosario / Erythrocyte glucose-6-phosphate dehydrogenase deficiency in Rosario / Deficiência de glicose-6-fosfato desidrogenase eritrocitária em Rosario

Se estudió la actividad enzimática (AE) de la enzima glucosa-6-fosfato deshidrogenasa eritrocitaria (G6PD) y la movilidad electroforética (ME) en una población de hombres y mujeres de la ciudad de Rosario (provincia de Santa Fe), Argentina y zona de influencia. Para la determinación de AE se utilizó la técnica cinética de Glock y McLean y para la electroforesis de la enzima, la técnica de M.C. Rattazzi y L.C. Bernini en acetato de celulosa. Los valores normales de actividad enzimática (AE) para hombres y mujeres adultos fueron de 8,1 ± 1,4 UI G6PD/g Hb. Se demostró que los valores de AE son independientes de la edad, sexo y concentración de hemoglobina. En todos los grupos etarios estudiados no se observaron diferencias significativas de AE con respecto a los adultos normales a excepción de los neonatos que presentaron un significativo aumento de la misma, lo cual está directamente relacionado con las características fisiológicas de los eritrocitos del recién nacido. Entre los 686 individuos estudiados se detectaron 2 pacientes deficientes de G6PD, lo que dio una prevalencia de 0,3% y el patrón electroforético correspondiente a esta población fue 98% (n: 672) para G6PD B y 2% (n: 14) para G6PD con movilidad rápida tipo A.

Enzymatic activity (EA) of erythrocyte glucose-6-phosphate dehydrogenase (G6PD) and electrophoretic mobility (EM) have been studied in a population of males and females in the city of Rosario and its area of influence. To determine EA, the Glock and McLean kinetic technique was used. Electrophoretic mobility assay was performed by M.C. Rattazzi and L.C. Bernini technique in cellulose acetate gel. Results demonstrated that the EA values in normal individual are independent of age, sex and hemoglobin values. The normal values of EA were: 8.1±1.4 IU of G6PD/g Hb. There were no significant differences in different age groups studied regarding healthy adults, except for neonatal group that yielded a significant EA increase which is directly related to the physiological characteristics of newborn erythrocytes. Two patients out of 686 individuals bearing G6PD deficiency were detected, corresponding to 0.3% prevalence. The electrophorectic mobility pattern was 98% (n: 672) for G6PD B, and 2% (n: 14) for G6PD A fast mobility variant.

Foi estudada a atividade enzimática (AE) da enzima glicose-6-fosfato desidrogenase eritrocitária (G6PD) e a mobilidade eletroforética (ME) numa população de homens e mulheres da cidade de Rosario, província de Santa Fe, Argentina e zona de influência. Para a determinação da AE foi utilizada a técnica cinética de GlocK e Mc Lean e para a eletroforese da enzima a técnica de M.C. Rattazzi e L.C. Bernini em acetato de celulose. Os valores normais de atividade enzimática (AE) para homens e mulheres adultos foram de 8,1 ± 1,4 UI G6PD/g Hb. Foi demonstrado que os valores da AE são independentes da idade, sexo e concentração de hemoglobina. Em nenhum dos grupos etários estudados foram observadas diferenças significativas de AE no que diz respeito aos adultos normais, com exceção dos neonatos que apresentaram um significativo aumento da mesma, o qual está diretamente relacionado com as características fisiológicas dos eritrócitos do recém-nascido. Entre os 686 indivíduos estudados foram detectados 2 pacientes deficientes de G6PD, o que deu uma prevalência de 0,3% e o padrão eletroforético correspondente a esta população foi de 98% (n: 672) para a G6PD B e 2% (n: 14) para G6PD com mobilidade rápida tipo A.

Deficiencia de glucosa-6-fosfato deshidrogenasa eritrocitaria en Rosario / Erythrocyte glucose-6-phosphate dehydrogenase deficiency in Rosario / DeficiÛncia de glicose-6-fosfato desidrogenase eritrocitária em Rosario

Se estudió la actividad enzimática (AE) de la enzima glucosa-6-fosfato deshidrogenasa eritrocitaria (G6PD) y la movilidad electroforética (ME) en una población de hombres y mujeres de la ciudad de Rosario (provincia de Santa Fe), Argentina y zona de influencia. Para la determinación de AE se utilizó la técnica cinética de Glock y McLean y para la electroforesis de la enzima, la técnica de M.C. Rattazzi y L.C. Bernini en acetato de celulosa. Los valores normales de actividad enzimática (AE) para hombres y mujeres adultos fueron de 8,1 ± 1,4 UI G6PD/g Hb. Se demostró que los valores de AE son independientes de la edad, sexo y concentración de hemoglobina. En todos los grupos etarios estudiados no se observaron diferencias significativas de AE con respecto a los adultos normales a excepción de los neonatos que presentaron un significativo aumento de la misma, lo cual está directamente relacionado con las características fisiológicas de los eritrocitos del recién nacido. Entre los 686 individuos estudiados se detectaron 2 pacientes deficientes de G6PD, lo que dio una prevalencia de 0,3% y el patrón electroforético correspondiente a esta población fue 98% (n: 672) para G6PD B y 2% (n: 14) para G6PD con movilidad rápida tipo A.(AU)

Enzymatic activity (EA) of erythrocyte glucose-6-phosphate dehydrogenase (G6PD) and electrophoretic mobility (EM) have been studied in a population of males and females in the city of Rosario and its area of influence. To determine EA, the Glock and McLean kinetic technique was used. Electrophoretic mobility assay was performed by M.C. Rattazzi and L.C. Bernini technique in cellulose acetate gel. Results demonstrated that the EA values in normal individual are independent of age, sex and hemoglobin values. The normal values of EA were: 8.1±1.4 IU of G6PD/g Hb. There were no significant differences in different age groups studied regarding healthy adults, except for neonatal group that yielded a significant EA increase which is directly related to the physiological characteristics of newborn erythrocytes. Two patients out of 686 individuals bearing G6PD deficiency were detected, corresponding to 0.3% prevalence. The electrophorectic mobility pattern was 98% (n: 672) for G6PD B, and 2% (n: 14) for G6PD A fast mobility variant.(AU)

Foi estudada a atividade enzimática (AE) da enzima glicose-6-fosfato desidrogenase eritrocitária (G6PD) e a mobilidade eletroforética (ME) numa populaþÒo de homens e mulheres da cidade de Rosario, província de Santa Fe, Argentina e zona de influÛncia. Para a determinaþÒo da AE foi utilizada a técnica cinética de GlocK e Mc Lean e para a eletroforese da enzima a técnica de M.C. Rattazzi e L.C. Bernini em acetato de celulose. Os valores normais de atividade enzimática (AE) para homens e mulheres adultos foram de 8,1 ± 1,4 UI G6PD/g Hb. Foi demonstrado que os valores da AE sÒo independentes da idade, sexo e concentraþÒo de hemoglobina. Em nenhum dos grupos etários estudados foram observadas diferenþas significativas de AE no que diz respeito aos adultos normais, com exceþÒo dos neonatos que apresentaram um significativo aumento da mesma, o qual está diretamente relacionado com as características fisiológicas dos eritrócitos do recém-nascido. Entre os 686 indivíduos estudados foram detectados 2 pacientes deficientes de G6PD, o que deu uma prevalÛncia de 0,3% e o padrÒo eletroforético correspondente a esta populaþÒo foi de 98% (n: 672) para a G6PD B e 2% (n: 14) para G6PD com mobilidade rápida tipo A.(AU)

[Hemolytic anemia due to hemoglobin Evans in an Argentinean family]. / Anemia hemolítica causada por hemoglobina Evans en una familia argentina.

Unstable hemoglobins are structural variants of the hemoglobin molecule, mostly originated by single amino-acid replacement in some globin chains. These changes affect molecule stability, leading to loss of solubility, precipitation, and cellular lysis. Patients carrying these unstable hemoglobins may present mild to severe chronic hemolytic anemia. Hemoglobin Evans is an unstable variant originated by replacement of valine with methionine at position 62 of the α-globin chain. We have identified this variant in a girl with an acute hemolytic crisis associated to pharyngitis, as well as in two of her family members. This is the third case of hemolytic anemia due to hemoglobin Evans reported in the literature.

Compound heterozygosity of Hb Q India (α64 (E13) ASP→HIS) and -α3,7 thalassemia. First report from Argentina / Heterocigosis de la Hb Q India (α64 (E13) ASP →HIS) y -α3,7 thalassemia. Primer informe desde Argentina

Hemoglobine (Hb) Q-India is an innocuous αglobin variant: α64 Asp → His. DNA sequencing studies have shown that the Hb Q India mutation is GAC → CAC in codon 64 of the α1 gene. Hb Q-India is a well-known hemoglobin variant in South-East Asia but only isolated case reports exist in literature to describe this rare entity in the rest of de world. The variant has been found with various forms of αand ß thalassemia. This hemoglobin has the same electrophoretic mobility as Hb S. We report, for the first time, the identification of Hb Q-India in an Argentinian woman (her parents came from Gibraltar), referred to our laboratory bearing a mild microcytic hypocromic anemia; a co-inherited α+ thalassemia (-α3.7 th) was also found.

La hemoglobina (Hb) Q India es una hemoglobina anormal e inocua que afecta la cadena α de esta. Los análisis de secuencia han demostrado que la mutación se encuentra en el codon 64 GAC → CAC del gen α1. Si bien es una variante muy conocida en el sudeste asiático, solo se han reportado pocos casos en el resto del mundo. Esta hemoglobina anormal se ha encontrado asociada con diversas formas de α y ß talasemia y su posición electroforética es idéntica a la de la Hb S. Reportamos, por primera vez, la identificación de la Hb Q India en una mujer Argentina (cuyos padres procedían del Peñón de Gibraltar), enviada a nuestro laboratorio por padecer de anemia microcítica hipocrómica, en la que se encontró también la coexistencia de α+ talasemia (-α3,7 th).

Anemia hemolítica causada por hemoglobina evans en una familia argentina / Hemolytic anemia due to hemoglobin evans in an Argentinean family

Las hemoglobinas inestables son variantes estructurales de lamolécula de hemoglobina originadas, en su mayoría, por sustitucionespuntuales de aminoácidos en alguna de las cadenas de globina. Estos cambios afectan la estabilidad de la molécula,causan pérdida de la solubilidad y precipitación dentro del eritrocito, lo cual provoca su destrucción acelerada. Desde el punto de vista clínico, las hemoglobinas inestables puedenpresentar anemia hemolítica crónica de gravedad variable.La hemoglobina Evans es una hemoglobina inestable causadapor la sustitución de valina por metionina en la posición 62 de la cadena de alfa globina. Hemos identificado esta variante en una niña con crisis hemolítica aguda asociada a faringitis y en dos miembros de su grupo familiar. Éste es el tercer caso de anemia hemolítica congénita causada por hemoglobina Evans comunicado en la bibliografía mundial.

Unstable hemoglobins are structural variants of the hemoglobin molecule, mostly originated by single amino-acid replacement in some globin chains. These changes affect molecule stability, leading to loss of solubility, precipitation, and cellular lysis. Patients carrying these unstable hemoglobins may present mild to severe chronic hemolytic anemia. Hemoglobin Evans is an unstable variant originated by replacement of valine with methionine at position 62 of the αa-globin chain. We have identified this variant in a girl with an acute hemolytic crisis associated to pharyngitis, as well as in two of her family members. This is the third case of hemolytic anemia due to hemoglobin Evans reported in the literature.

Hb S-San Martin: a new sickling hemoglobin with two amino acid substitutions [ß6(A3)Glu→Val;ß105(G7)Leu→Pro] in an Argentinean family.

A new sickling hemoglobin (Hb) detected in an Argentinean family from San Martín, Buenos Aires, Argentina, is hereby described. Two mutations were identified on the same ß-globin gene resulting in a new variant named Hb San Martin. One mutation was found on exon 1, corresponding to Hb S [ß6Glu→Val, GAG>GTG] and the second one on exon 3 at ß105(G7)Leu→Pro, CTC>CCC. The replacement of leucine by proline will likely impair the structure breaking helix G and causing instability of the molecule and the clinical manifestations typical of unstable Hbs. The mutation at ß105 seemed to be a de novo one in our patients, arising on a previously mutated gene, due to the fact that Hb S is the most frequent structural variant.

[Severe hemolytic anemia due to hemoglobin Hammersmith]. / Anemia hemolítica grave causada por hemoglobina Hammersmith.

Most of the hemoglobin variants are the result of single amino acid replacement in one of the globin chains. In many cases, these hemoglobinopathies are harmless, while in others they determine alterations in the physical and chemical properties, raising clinical manifestations of variable severity. In the unstable hemoglobinopathies, the changes reduce solubility, inducing the formation of precipitates of denaturated hemoglobin (Heinz bodies), which damage the membrane and finally destroy the red blood cells prematurely. Up to now, more than 150 different unstable hemoglobins have been described; most of them cause chronic hemolysis, increased by infections or drugs. We report the clinical presentation of an unstable hemoglobin (hemoglobin Hammersmith) in a girl with severe hemolytic anemia, splenomegaly and red blood cell requirement.

Anticoagulante Lúpico: Sensibilidad de 19 reactivos comerciales de tiempo de tromboplastina parcial activado / Lupus Anticoagulant: Sensitivity of 19 commercial activated partial thromboplastin time reagents

El Anticoagulante Lúpico (AL) constituye una familia de inmunoglobulinas que interfieren las pruebas de coagulación dependientes de fosfolípidos. Hay una gran variedad de pruebas que permiten detectar y confirmar la presencia de AL en el plasma de un paciente. Sin embargo, el tiempo de tromboplastina parcial activado (TTPA) sigue siendo una de las pruebas más utilizadas para la detección de dicho inhibidor. Teniendo en cuenta la importancia clínica de su diagnóstico de laboratorio, se dicidió estudiar la sensibilidad, para detectar AL, de 19 reactivos comerciales de TTPA. Se obtuvieron varias conclusiones importantes: No se encontró relación entre sensibilidad y tamaño de los liposomas; tampoco con la uniformidad de los mismos. La fuente de fosfolípido y el tipo de activador no son suficientes para explicar las diferencias en sensibilidad de los reactivos. Finalmente, se encontró una correlación negativa entre la sensibilidad y la concentración total de fosfolípido del reactivo. A menor concentración de fosfolípido, mayor sensibilidad.

Lupus anticoagulants (LA) are immunoglobulins which interfere in in vitro phospholipid-dependent coagulation tests. Various methods have been proposed; however, activated partial thromboplastin time (APTT) is the most used screening test for lupus anticoagulant. Previous studies have shown that sensitivity to the lupus anticoagulant defect varies considerably with different APTT reagents. In view of the undoubted clinical importance of lupus anticoagulants, the sensitivity of 19 commercial APTT reagents has been evaluated. The study raises several important conclusions: No difference was found in sensitivity associated with a narrower distribution of liposomes' diameter, considering the latter as a marker of uniformity in phospholipid distribution. The source of the platelet substitute and the nature of the contact phase activator are unlikely to determine such varied sensitivity. Finally, a significant negative correlation between APTT sensitivity and total phospholipid concentration was found. The lower the phospholipid concentration, the higher the APTT sensitivity to AL.

New evidence of red blood cell rheological disorders in beta-thalassaemia minor.

Haemorheological parameters, such as red blood cell deformability, membrane elastic modulus and membrane surface viscosity in twenty one thalassaemia heterozygous patients (14 beta0/beta and 7 beta+/beta) were compared with normal individuals (n = 15). Parameters were measured applying a laser diffractometric method (ektacytometry). Thalassaemia erythrocytes showed statistically significant lower deformability and higher elastic modulus. Surface viscosity showed no significant differences in thalassaemia. Creep and recovery curves were registered by diffractometry. The normal recovery curve was fitted by a first order exponential decay function, expressing the fitting degree by the chi2 coefficient. The shape of the recovery curve in beta-thalassaemia patients (beta0/beta or beta+/beta) was significantly different from the control group. The possible mechanism of red blood cells abnormal rheological behaviour in beta-thalassaemia minor could be explained by a surface charge reduction. Our results enable us to conclude that the shape of the recovery curve (chi2 coefficient) could be considered as a marker that might be useful in beta-thalassaemia diagnosis.

Hematologic study of newborn umbilical cord blood

Hematological parameters in newborn umbilical cord blood samples (n=476), collected at the Hospital Provincial del Centenario, Rosario, were studied. They were divided into 3 groups: (I) full term newborns with weight according to gestational age; II) low weight and normal gestational age; (III) preterm newborns. The results were as follows: group (I) Hb: 15.5 + 1.1 g/dl; RBC: 4.66 + 0.33 x 1012/I; PCV:49 + 4.3 percent, MCV 105.1 + 5.3 fl; MHC: 33.2 + 1.2 pg. Decreased Hb concentration (p<0.05) and increased MCV (p<0.01) were observed in preterm newborns in comparison with normal ones, and a slight PCV increase and RBC values in low weight newborns compared to the control group (p<0.05). Erytrocyte morphology was normal as well as reticulocyte values in these samples. The electrophoretic pattern was (FA) with the following Hb F values 66.3 + 6.8 percent, and Hb A2 0.45 + 0.3 percent in group (I), with a significant increase of Hb F in 30-35 weeks preterm newborns. Group(I) values are considered as normal hematological parameters in newborns in our country, whereas MCV< 94.7 fl is considered as a neonatal microcytosis marker, consequently an alert to investigate alpha-thalassemia. There was no influence on Hb concentration due to maternal smoking habit. The present work could be of relevance for our region since up to the present time there are no similar records.

Hematologic study of newborn umbilical cord blood

Hematological parameters in newborn umbilical cord blood samples (n=476), collected at the Hospital Provincial del Centenario, Rosario, were studied. They were divided into 3 groups: (I) full term newborns with weight according to gestational age; II) low weight and normal gestational age; (III) preterm newborns. The results were as follows: group (I) Hb: 15.5 + 1.1 g/dl; RBC: 4.66 + 0.33 x 1012/I; PCV:49 + 4.3 percent, MCV 105.1 + 5.3 fl; MHC: 33.2 + 1.2 pg. Decreased Hb concentration (p<0.05) and increased MCV (p<0.01) were observed in preterm newborns in comparison with normal ones, and a slight PCV increase and RBC values in low weight newborns compared to the control group (p<0.05). Erytrocyte morphology was normal as well as reticulocyte values in these samples. The electrophoretic pattern was (FA) with the following Hb F values 66.3 + 6.8 percent, and Hb A2 0.45 + 0.3 percent in group (I), with a significant increase of Hb F in 30-35 weeks preterm newborns. Group(I) values are considered as normal hematological parameters in newborns in our country, whereas MCV< 94.7 fl is considered as a neonatal microcytosis marker, consequently an alert to investigate alpha-thalassemia. There was no influence on Hb concentration due to maternal smoking habit. The present work could be of relevance for our region since up to the present time there are no similar records. (AU)