- or hemolytic disease of the newbornAnemia in an infant, caused when a pregnant woman produces antibodies to an antigen in her fetus's red blood cells.An Rh-negative woman (see Rh blood-group system) with an Rh-positive fetus whose ABO blood group (see ABO blood-group system) matches hers is likely to have an immune reaction after the first such pregnancy, which sensitizes her when fetal red blood cells enter her bloodstream, usually during labour. If blood typing shows incompatibility, an anti-Rh antibody injection given to the mother after the birth can destroy the fetal red cells, thus preventing trouble in a future pregnancy. If amniocentesis detects products of blood destruction, Rh-negative blood transfusions to the fetus before birth or exchange transfusion after it may save the baby's life. ABO incompatibilities are more common but usually less severe.
* * *also called hemolytic disease of the newborntype of anemia in which the red blood cells (erythrocytes (erythrocyte)) of a fetus are destroyed in a maternal immune reaction resulting from a blood group incompatibility between the fetus and its mother. This incompatibility arises when the fetus inherits a certain blood factor from the father that is absent in the mother. Symptoms of erythroblastosis fetalis range from mild to severe; death of the fetus or newborn sometimes results.Two blood group systems, Rh (Rh blood group system) and ABO (ABO blood group system), primarily are associated with erythroblastosis fetalis. The Rh system is responsible for the most severe form of the disease, which can occur when an Rh-negative woman (a woman whose blood cells lack the Rh factor) conceives an Rh-positive fetus. Sensitization of the mother's immune system (immunization) occurs when fetal red blood cells that carry the Rh factor (an antigen in this context) cross the placental barrier and enter the mother's bloodstream. They stimulate the production of antibodies (antibody), some of which pass across the placenta into fetal circulation and lyse, or break apart, the red blood cells of the fetus ( hemolysis).It is rare for a mother to become sensitized during the course of her first Rh-positive pregnancy because the amount of fetal Rh antigen that enters maternal circulation is insufficient to cause sensitization; usually only during labour will exposure be significant. However, because Rh sensitivity is likely to develop during labour, the risk of the disease developing in subsequent Rh-positive pregnancies increases. The risk can be reduced if the mother receives injections of Rh immunoglobulin, which destroys fetal red blood cells in her bloodstream, during her first pregnancy. The fetus also is protected from Rh hemolytic disease if an ABO blood group incompatibility exists concurrently; protection is conferred by ABO antibodies, which destroy fetal blood cells in the maternal circulation before the mother develops Rh sensitivity. Fetal-maternal incompatibilities within the ABO blood group alone are more common than those of the Rh type, but the immune reaction is usually much less severe, unless the fetus is type A and the mother type O.The severity of erythroblastosis fetalis varies depending on the degree of hemolysis. Symptoms include anemia, with the presence of many immature red blood cells (erythroblasts) in the circulation; jaundice, resulting from a buildup of bilirubin (a breakdown product of hemoglobin from red blood cells); and an enlarged liver and spleen. In its mildest form, the disease manifests only as slight anemia with no other complications; in its most extreme form, the fetus dies in utero. Hydrops fetalis, which is characterized by extreme edema (abnormal accumulation of serous fluid) and congestive heart failure, is the most severe form of the disease in newborns. Usually the infant dies, unless an exchange transfusion (blood transfusion) in which the Rh-positive blood of the infant is replaced by Rh-negative blood is successful. A complication of erythroblastosis fetalis is kernicterus, which is caused by deposition of bilirubin in the brain. Hearing loss, mental retardation, or death may result. Nevertheless, many procedures are available to avert these consequences. If it is determined that the fetus is at risk for erythroblastosis fetalis, amniocentesis can be used to measure bilirubin concentrations and predict the severity of the disease. If levels are elevated, intrauterine transfusions of Rh-negative blood can be given until premature delivery can be induced. These measures, together with the use of Rh immunoglobulin, have almost eliminated the incidence of erythroblastosis fetalis in developed countries.
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erythroblastosis fetalis — erythroblastosis fetalis. См. эритробластоз плода. (Источник: «Англо русский толковый словарь генетических терминов». Арефьев В.А., Лисовенко Л.А., Москва: Изд во ВНИРО, 1995 г.) … Молекулярная биология и генетика. Толковый словарь.
erythroblastosis fetalis — erythroblastosis fe·ta·lis fi tal əs n a hemolytic disease of the fetus and newborn that is characterized by an increase in circulating erythroblasts and by jaundice and that occurs when the system of an Rh negative mother produces antibodies to… … Medical dictionary
erythroblastosis fetalis — noun A medical condition where an rh negative mothers antibodies attack the red blood cells of an rh positive fetus. See Also: erythroblastosis, erythroblastosis neonatorum, hemolytic disease … Wiktionary
erythroblastosis fetalis — noun Etymology: New Latin, fetal erythroblastosis Date: circa 1934 a hemolytic disease of the fetus and newborn that occurs when the system of an Rh negative mother produces antibodies to an antigen in the blood of an Rh positive fetus which… … New Collegiate Dictionary
erythroblastosis fetalis — noun severe anemia in newborn babies; the result of Rh incompatibility between maternal and fetal blood; typically occurs when the child of an Rh negative mother inherits Rh positive blood from the father; can be diagnosed before birth by… … Useful english dictionary
erythroblastosis fetalis — Severe haemolytic disease of the neonate as a result of transplacental passage of maternal antibodies mainly directed against Rhesus blood group antigens … Dictionary of molecular biology
erythroblastosis fe|tal|is — «fih TAL ihs», erythroblastosis of the fetus: »Erythroblastosis fetalis occurs in about 10 per cent of the cases when an Rh negative mother is pregnant with an Rh positive baby (New York Times). ╂[< New Latin erythroblastosis fetalis fetal… … Useful english dictionary
fetalis — see ERYTHROBLASTOSIS FETALIS, HYDROPS FETALIS … Medical dictionary
erythroblastosis neonatorum — erythroblastosis ne·o·na·to·rum .nē ə nə tōr əm n ERYTHROBLASTOSIS FETALIS … Medical dictionary
erythroblastosis — [fi tal′ise rith΄rō blas tō′sis] n. 1. the appearance of immature, nucleate red blood cells in the circulating blood 2. a disease of the developing fetus and newborn infant, characterized by a hemolytic anemia and jaundice and caused by an… … English World dictionary