Late hyporegenerative anemia in neonates with rhesus hemolytic disease

Abstract

This study was conducted to determine the risk factors of the late hyporegenerative anemia in Rh-isoimmunized infants. Data on 36 infants with rhesus hemolytic disease were analyzed. The mean gestational age and birth weight were 36 +/- 1.3 weeks and 2837 +/- 403 grams respectively. Twenty-seven infants (75%) received between 2 and 8 intravascular intrauterine blood transfusions. Fourteen infants (39%) required simple packed red blood cell transfusions and 11 infants (31%) required exchange blood transfusion in the immediate postnatal period. Thirty infants (83%) developed late anemia and required blood transfusions at a mean postnatal age of 43.3 +/- 15.7 days. Sixty-four percent of infants who had exchange blood transfusions did not develop late anemia, while 92% of infants who did not require exchange blood transfusion developed late anemia, and the difference was statistically significant (P = 0.035). Serum erythropoietin levels were determined in 8 infants immediately before simple transfusion for late anemia. The media serum erythropoietin level was 21.2 mU/ml, ranging between less than 10 to 114.2 mU/ml. We conclude that late hyporegenerative anemia is common among Rh isoimmunized infants, regardless of the intravascular intrauterine transfusion. Exchange blood transfusion was associated with less occurrence of late anemia.

Neonatal management and outcome in alloimmune hemolytic disease

“…Anemia in hemolytic disease is divided in early anemia (onset at birth up to 7 days of age) and late anemia. Late anemia occurs in 83% of neonates of a gestational age of 35 weeks or more with HDFN and is further split into 'late hyporegenerative anemia' and 'late anemia of hemolytic disease' [59]. Late hyporegenerative anemia is caused by depressed erythropoiesis and is characterized subsequently by low reticulocyte counts.…”

“…Late anemia of hemolytic disease is characterized by age-appropriate or elevated reticulocyte counts, reflecting an active bone marrow to compensate for the shortened erythrocyte survival. This form of late anemia is thought to be due to a combination of continuing hemolysis by remaining antibodies, shortened survival of transfused erythrocytes, natural decline of the hemoglobin level, and the expanding intravascular volume of the growing neonate [59,60].…”

“…Late anemia usually resolves by the third month of life; until then, erythrocyte transfusions may be necessary to treat postpartum anemia [59,61]. The mean postnatal age for a first topup transfusion in HDFN is 18 days (range 1-34) [62].…”

“…The mean postnatal age for a first topup transfusion in HDFN is 18 days (range 1-34) [62]. At least one top-up transfusion is reported to be required in 68-83% of neonates with HDFN [33,59,63]. Some neonates need up to six top-up transfusions in the first 3 months of life [62].…”

“…Some neonates need up to six top-up transfusions in the first 3 months of life [62]. In neonates that were treated with IUTs, the top-up transfusion rate is significantly higher (77-89%), than in neonates that were not treated with IUTs (27-67%) [33,59,63]. In the IUT group, the median number of top-up transfusions was 1 (range, 0-4), compared to 0 (range, 0-2) in non-IUT group (p < 0.01) [33].…”