Isoantibodies, prevalence and risk factors in two hospitals in Mexico / Isoanticuerpos, prevalencia y factores de riesgo en dos hospitales de México

Background: Erythrocyte isoimmunization or alloimmunization is a late complication of transfusion, in which antibodies against erythrocyte antigens other than the ABO system are developed. Its prevalence is variable, groups of patients with low prevalence (2%) and others of high risk with more than 50% have been described. These antibodies can have serious clinical repercussions in transfused patients. Objective: To know the prevalence of erythrocyte isoimmunization, the risk factors for its development and the types of antibodies developed in the user population of two hospitals in Mexico. Methods: Retrospective study. The database of the Blood Bank and the Transfusion Service of two hospitals was analyzed for the search of transfused patients who developed isoantibodies from 2012 to 2016, analyzing their background to determine the risk factors, prevalence and type of antibodies. Results: An isoimmunization prevalence of 0.97% was found in 5 years; the main antibodies found were: anti-E, anti-K, anti-C, anti-Dia, anti-c, anti-D and anti-Fya. The associated risk factors for the development of isoimmunization were: transfusion history, pregnancy and female sex, as a finding it was found that group O is a protective factor. Conclusions: Erythrocyte alloimmunization in the population studied corresponded to a low prevalence. The main antibodies found were against Rh, Kell and Diego system antigens, with a different distribution than published in other international series. No previous report was found about the finding on group O as a protective factor for isoimmunization.

Introducción: la isoinmunización o aloinmunización eritrocitaria es una complicación tardía de la transfusión, en la cual se desarrollan anticuerpos contra antígenos eritrocitarios diferentes al sistema ABO. Su prevalencia es variable, se han descrito grupos de pacientes con baja prevalencia (2%) y otros de alto riesgo con más del 50%. Estos anticuerpos pueden tener repercusiones clínicas graves en los pacientes transfundidos. Objetivo: conocer la prevalencia de la isoinmunización eritrocitaria, los factores de riesgo para su desarrollo y los tipos de anticuerpos desarrollados en la población usuaria de dos hospitales en México. Métodos: estudio retrospectivo. Se analizó la base de datos del banco de sangre y del servicio de transfusión de dos hospitales para la búsqueda de pacientes transfundidos que desarrollaron isoanticuerpos del año 2012 al 2016, analizando sus antecedentes para determinar los factores de riesgo, prevalencia y tipo de anticuerpos. Resultados: se encontró una prevalencia de isoinmunización del 0.97% en 5 años; los principales anticuerpos encontrados fueron: anti-E, anti-K, anti-C, anti-Dia, anti-c, anti-D y anti-Fya. Los factores de riesgo asociados para el desarrollo de isoinmunización fueron: antecedentes transfusionales, embarazo y el sexo femenino, como hallazgo se encontró que el grupo O es un factor protector. Conclusiones: la aloinmunización eritrocitaria en la población estudiada correspondió a una prevalencia baja. Los principales anticuerpos encontrados fueron contra antígenos del sistema Rh, Kell y Diego, con una distribución diferente a lo publicado en otras series internacionales. No se encontró reporte previo acerca del hallazgo sobre el grupo O como factor protector para isoinmunización.

[Severe hyperbilirubinemia in newborns, risk factors and neurological outcomes]. / Hiperbilirrubinemia severa en Recién Nacidos, factores de riesgo y secuelas neurológicas.

INTRODUCTION: Hyperbilirubinemia is highly prevalent in newborns, with risk of neurological invol vement with bilirubinemia higher than 20 to 25 mg/dl. This progression is preventable with early de tection and treatment. OBJECTIVE: To describe the incidence and associated factors in hospitalized pa tients with hyperbilirubinemia higher than 20 mg/dl, and the follow-up of symptomatic cases during hospitalization. PATIENTS AND METHOD: Retrospective study of patients with severe hyperbilirubine mia, between 2013 and 2016. Risk factors were evaluated, stratifying by bilirubin level, admission age, and gestational age. The data were compared with Fisher's exact test, chi-square test, and relative risk (RR) in an Excel database, with an alpha error of p <0.05. The data were obtained from the electronic discharge summary and the medical record of secondary level follow-up. RESULTS: During the studied period, out of 25,288 live newborns (NB), 593 were hospitalized due to hyperbilirubinemia higher than 20 mg/dl, one per each 42 live NB; and 59 with bilirubinemia higher than 25 mg/dl, one per each 428 live NB. Hyperbilirubinemia was more frequent in males, with RR 1.22 (95% CI 1.04-1.44), and in late preterm newborns, with RR 2.39 (95% CI 1.96-2.93) compared with term NB. In those admitted with more than four days, the main associated factor was excessive weight loss, whereas in the first three days was classic group incompatibility. Three of ten cases with acute encephalopathy persisted with neurological involvement, which means 11.8 per 100,000 live births. CONCLUSIONS: The main risk factors for developing severe hyperbilirubinemia were prematurity, excessive weight loss, classic group incompatibility, and male sex. These findings allow to focus attention on risk groups and decrease the probability of neurological damage.

Potential effect of using ABO-compatible living-donor liver transplantation.

Liver transplantation increased 1.84-fold from 1988 to 2004. However, the number of patients on the waiting list for a liver increased 2.71-fold, from 553 to 1500. We used a mathematical equation to analyze the potential effect of using ABO-compatible living-donor liver transplantation (LDLT) on both our liver transplantation program and the waiting list. We calculated the prevalence distribution of blood groups (O, A, B, and AB) in the population and the probability of having a compatible parent or sibling for LDLT. The incidence of ABO compatibility in the overall population was as follows: A, 0.31; B, 0.133; O, 0.512; and AB, 0.04. The ABO compatibility for parent donors was blood group A, 0.174; B, 0.06; O, 0.152; and AB, 0.03; and for sibling donors was A, 0.121; B, 0.05; O, 0.354; and AB, 0.03. Use of LDLT can reduce the pressure on our liver transplantation waiting list by decreasing its size by at least 16.5% at 20 years after its introduction. Such a program could save an estimated 3600 lives over the same period.

[Prevalence of immunohematologic tests at birth and the incidence of hemolytic disease in the newborn]. / Prevalência de marcadores imuno-hematológicos em recém-nascidos ao nascimento e em suas respectivas m es e incidência de doença hemolítica numa maternidade de São Paulo.

UNLABELLED: The administration of anti-D globulin to the mothers has decreased the incidence of Rh hemolytic disease but the improvement of technologic assays has made it possible to identify several hemolytics diseases of the newborn. BACKGROUND: To identify the prevalence of immunohematologic tests demonstrated by indirect (IC), direct (DC) and elution tests; to identify the incidence of hemolytic disease and its treatment (phototherapy and/or exchange transfusion) in neonates with hemolytic disease. This is a retrospective cohort-study performed from January 1st 1996 to July 1st 1998. METHODS: This is a descriptive study of the immunohematologic profile of 1698 mothers and their offsprings, as risk factors for developing hemolytic disease. The inclusion criteria were the positivity of the indirect (IC) and direct (DC) Coombs tests and elution tests. Based on the inclusion criteria three group of infants were analyzed: Group I was composed of 149 offsprings of Coombs-positive mothers (IC+) with antibodies associated with neonatal hemolytic disease. This group was further divided into two groups: Group I-A (IC+DC+) was composed of 83 Coombs-positive offsprings (DC+) of Coombs-positive mothers (IC+) and Group I-B (IC+DC-) was composed of 66 Coombs-negative offsprings (DC-) of Coombs-positive mothers (IC+); Group D was composed of 736 Coombs-positive offspring's of Coombs-negative mothers (IC-); and Group E was composed of 807 Coombs-negative and elution-positive offspring's of Coombs-negative mothers. RESULTS: This study shown that the overall prevalence of immunohematologic tests associated with hemolytic disease was 9.07% (3212/35429), 0.43% (154/35429) among offsprings of Coombs-positive mothers, 4.10% (1453/35429) among Coombs-positive infants, and 4.53% (1605/35429) among elution-positive infants. The overall incidence of hemolytic disease was 36.23% (613/1692), 33.56% (50/149) among offspring's of Coombs-positive mothers, 44.43% (327/736) among Coombs-positive infants, and 29.24% (236/807) among elution-positive infants. The overall incidence of phototherapy among infants with hemolytic disease was 36.23% (613/1692), 49.40% (41/83) in group I-A (IC+DC+), 13.64% (9/66) in group I-B(IC+DC-), 44.43% (327/736) in group D, and 29.24% (236/807) in group E. The overall incidence of exchange transfusion among infants with hemolytic disease was 0.88% (15/1692), 14.46% (12/83) in group I-A (IC+DC+), 0% (0/66) in group I-B (IC+DC-), 0.27% (2/736) in group D, and 0.12% (1/807) in group E. CONCLUSIONS: The results of this study allowed us to conclude that the overall prevalence of immunohematologic tests associated with hemolytic disease was 9.07% (3212/35429) and the overall incidence of hemolytic disease was 36.23% (613/1692) in this study-group. The highest incidences of hemolytic disease and phototherapy were observed among Coombs-positive offsprings of Coombs-positive mothers.

[Blood group frequencies and ABO and RhD incompatibilities in La Paz, Baja California Sur, Mexico]. / Frecuencias de grupos sanguíneos e incompatibilidades ABO y RhD, en La Paz, Baja California Sur, México.

OBJECTIVE: To determine genic and phenotypic frequencies and predict the risk of incompatibility and maternal alloimmunization in the population of La Paz. MATERIAL AND METHODS: This descriptive study evaluated 1809 voluntary blood donors attending in 1998 the Hospital General de Zona of Instituto Mexicano del Seguro Social (Zone General Hospital of the Mexican Institute of Social Security) in La Paz, Baja California Sur, Mexico. Blood donors were typified by tube agglutination. The gene frequencies were estimated assuming equilibrium conditions, and incompatibilities and alloimmunization were statistically assessed with the chi 2 test. RESULTS: Percent frequencies were as follows: blood group O, 58.49%; A, 31.40%; B, 8.40%; AB, 1.71%; RhD, 95.36%; and RhD negative, 4.64%. Genic frequencies were: i, 0.7648; IA, 0.1821; IB, 0.0519; D, 0.7845; and d, 0.2155, respectively. Incompatibilities between couples and mother-child were 0.3023 and 0.1685 for ABO, 0.0442 and 0.0364 for RhD, and 0.0134 and 0.0061 for double incompatibility, respectively. The probability of maternal alloimmunization was estimated at 0.0309. CONCLUSIONS: The O and RhD groups were the most common in La Paz, although frequencies were among the lowest in Mexico, contrary to the case of A and RhD negative groups. The probabilities of maternal alloimmunization and of incompatibilities were also high. Ancestral white, black, and indigenous groups admixed in the northwestern part of Mexico; after migrating to Baja California Sur the admixture of the population probably became similar to that of the remainder of the northwestern area.

Frecuencias de grupos sanguíneos e incompatibilidades ABO y RhD, en La Paz, Baja California Sur, México / Blood group frequencies and ABO and RhD incompatibilities in La Paz, Baja California Sur, Mexico

OBJECTIVE: To determine genic and phenotypic frequencies and predict the risk of incompatibility and maternal alloimmunization in the population of La Paz. MATERIAL AND METHODS: This descriptive study evaluated 1809 voluntary blood donors attending in 1998 the Hospital General de Zona of Instituto Mexicano del Seguro Social (Zone General Hospital of the Mexican Institute of Social Security) in La Paz, Baja California Sur, Mexico. Blood donors were typified by tube agglutination. The gene frequencies were estimated assuming equilibrium conditions, and incompatibilities and alloimmunization were statistically assessed with the chi 2 test. RESULTS: Percent frequencies were as follows: blood group O, 58.49; A, 31.40; B, 8.40; AB, 1.71; RhD, 95.36; and RhD negative, 4.64. Genic frequencies were: i, 0.7648; IA, 0.1821; IB, 0.0519; D, 0.7845; and d, 0.2155, respectively. Incompatibilities between couples and mother-child were 0.3023 and 0.1685 for ABO, 0.0442 and 0.0364 for RhD, and 0.0134 and 0.0061 for double incompatibility, respectively. The probability of maternal alloimmunization was estimated at 0.0309. CONCLUSIONS: The O and RhD groups were the most common in La Paz, although frequencies were among the lowest in Mexico, contrary to the case of A and RhD negative groups. The probabilities of maternal alloimmunization and of incompatibilities were also high. Ancestral white, black, and indigenous groups admixed in the northwestern part of Mexico; after migrating to Baja California Sur the admixture of the population probably became similar to that of the remainder of the northwestern area.

Prevalence and lack of clinical significance of blood group incompatibility in mothers with blood type A or B.

PURPOSE: To examine the prevalence and clinical significance of blood group incompatibility in infants whose mothers have blood type A or B. METHODS: We prospectively analyzed cord blood samples from 4996 consecutive love-born infants for blood type, hematocrit, and results of direct antiglobulin (Coombs) test (DAT) and indirect Coombs test (ICT). OUTCOME MEASURES: Erythrocyte sensitization was determined by positive DAT or ICT results. Significant hyperbilirubinemia (> or = 224 mumol/L (12.8 mg/dl) and mean cord hematocrits were compared between mother-infant pairs with ABO incompatibility and positive DAT or ICT results and those with negative Coombs test results. RESULTS: Of all births, 6.9% (343/4996) were of infants who had ABO incompatibility and had been born to mothers with blood type B or A; 44 (13%) of 343 infants had a positive antiglobulin test result, of whom 43 had a positive ICT result only. Type A or B mothers were 5.5 times less likely to have sensitization than type O mothers; A-B, B-A, A-AB, and B-AB mother-infant pairs with a positive antiglobulin test result had mean cord hematocrits and rates of significant hyperbilirubinemia similar to those of corresponding pairs whose antiglobulin tests both showed negative results. Infants with a positive DAT result had lower mean cord hematocrits than infants with negative results on both antiglobulin tests or on a positive ICT result only. Significant hyperbilirubinemia was more frequent in infants with a positive DAT result than in infants with negative results on both antiglobulin tests or a positive ICT result only. CONCLUSION: Sensitization is much rare when the mother has blood type A or B than when she has blood type O, as demonstrated by the antiglobulin test. The incidence of significant hyperbilirubinemia and lower cord hematocrit is not increased by sensitization when the mother has type A or B.

Evoluçäo clínica e laboratorial de crianças ictéricas com possibilidade de incompatibilidade sanguínea materno-fetal pelo sistema ABO, nascidas no Hospital das Clínicas de Ribeiräo Preto / Clinical and laboratorial course in children with jaundice with of maternal-fetal blood incompatibility by ABO system, born at the Hospital das Clínicas of Ribeiräo Preto

O presente estudo apresenta a evoluçäo clínica e laboratorial de crianças nascidas no Hospital das Clínicas da Faculdade de Medicina de Ribeiräo Preto (HCFMRP) com possibilidade de isoimunizaçäo materno-fetal pelo sistema ABO. Foram incluídas no trabalho 87 crianças que apresentaram icterícia, foram submetidas a fototerapia e tiveram seguimento ambulatorial completo. Estas crianças provieram de um total de 480 nascimentos ocorridos no ano de 1983 em que as mäes eram do tipo O e os recém-nascidos do tipo A ou B. Foram estudados as condiçöes de nascimento, os valores preditivos do teste de Coombs direto do sangue do cordäo, da pesquisa de hemolisina no sangue materno e do tempo de aparecimento da icterícia no diagnóstico da gravidade do quadro e a evoluçäo ambulatorial. As condiçöes de nascimento das crianças participantes do estudo foram semelhantes às do grupo-controle e da populaçäo geral. A maior gravidade do quadro näo foi associada a nenhum dos parâmetros testados (Coombs direto positivo, pesquisa de hemolisina positiva, icterícia precoce e tipo sangüíneo da criança A ou B). O seguimento das crianças demonstrou ser desnecessário o acompanhamento sistemático de seus níveis de hemoglobina. Conlui-se que o manejo das crianças com possibilidade de incompatibilidade ABO näo deve diferir do de outras crianças ictéricas. A monitoragem contínua e cuidadosa da bilirrubina plasmática nestas crianças tem mostrado ser o único meio prático de indicar a gravidade do caso

Los grupos sanguíneos ABO y Rh (D) en poblaciones de la Región Lagunera de México (Calculo de la frecuencia de incompatibilidad simple y doble en matrimónios y maternofetal) / ABO and Rh (D) blood groups in populations of the Laguna Region, Mexico. Estimate of simple and double incompatibility frequency in married subjects and maternal-fetal

Se determinaron los grupos sanguíneos de los sistemas ABO y Rh(D) en 9.351 personas que acudían a diferentes centros médicos de las ciudades de Torreon, Coahuila y Gomez Palacio, Durango en la Región Lagunera México; encontrándose los porcentajes siguientes para ABO: A, 26,37; B, 9,70; AB, 1,87; O, 62,06, y para Rh(D): Rh(D) +, 95,86 y Rh(D)-, 4,14. Con base en estas frecuencias se estimaron los porcentajes de matrimonios incompatibles siendo de 29,34 por ABO, 3,97 por Rh(D) y de 1,16 para ambos, y los porcentajes de incompatibilidad maternofetal siendo de 16,22 por ABO, 3,31 por Rh(D) y 0,54 para ambos. Se encontró que las frecuencias anteriores tanto de grupos sanguíneos como de incompatibilidad, eran intermedias a las informadas para poblaciones antecesoras, indígenas, mexicanos y españoles, y similares a lo encontrado en poblaciones mestizas del estado de Nuevo Leon, México

ABO and Rho(D) blood groups in IMSS population in the State of Nuevo León (estimation of simple and double incompatibility frequency in married couples and their offspring).

ABO and Rho (D) blood groups were studied in 61,023 people receiving medical care at the medical units or blood banks of the Instituto Mexicano del Seguro Social in the metropolitan area in the city of Monterrey, Nuevo León, so as to determine the genetical inheritance patterns that control these blood antigens, and that were used in the stimation of ABO and Rho (D) incompatibility in married couples and in births with maternal fetal incompatibility. It was found that IMSS populations, regardless of the medical units, can be considered as part of the same one and are different to those observed in blood banks. From the married couples, 28.58 percent were found to be incompatible with ABO and 7.15 percent with Rho (D); in 2.04 percent of cases, maternal fetal incompatibility had a ratio of 15.63 percent in the ABO group and 5.60 percent in the Rho (D) group. Double incompatibility was found in 0.88 percent of cases. The importance of these facts is stressed, considered as significant data for neonatologists and for those working in maternal fetal isoimmunization clinics.

Further evidence for a racial difference in frequency of ABO hemolytic disease.

The results of a Coombs test on each infant, age of onset of jaundice, and of maximum recorded serum indirect bilirubin concentration were statisically analyzed on 2,428 consecutive newborn infants who were Rh compatible with their mothers and who weighed 2.5 kg or more. The incidence of ABO isoimmune hemolytic disease was estimated by subtracting the frequency of each of these observations in ABO compatible infants from the corresponding frequency in ABO incompatible infants. This subtraction decreased the contribution of extraneous causes for jaundice and a positive Coombs reaction. As expected, these signs of hemolytic disease were found more often in ABO incompatible infants than in compatible infants. Whether detected by a positive Coombs reaction, jaundice in the first 24 hours, serum bilirubin concentrations over 10 mg/dl, or any combination thereof, the incidence of ABO disease was much higher in black neonates than in white ones. These findings indicate that early discharge of newborn infants from the hospital should not be authorized without specific assessments, especially when the infant is ABO incompatible and black.