Spectrum and outcome analysis of marked neonatal hyperbilirubinemia with blood group incompatibility.
BACKGROUND
Blood group mismatch between a mother and newborn carries a substantial risk for neonatal hyperbilirubinemia and kernicterus. In the current study, we investigate the spectrum and outcome of marked neonatal hyperbilirubinemia with blood group incompatibility.


METHODS
We retrospectively assessed a cohort of 413 neonates with peak total serum bilirubin (TSB) values > or = 20 mg/dL between 1995 and 2007. Those with a gestational age< 34 weeks, birth weight < 2000 grams or G6PD deficiency were excluded. A total of 83 subjects with blood group incompatibility were enrolled. Neonates with unknown etiology of hyperbilirubinemia (except breast milk feeding) were selected as the controls (n = 168). Kernicterus referred to classic neurological signs after follow up for more than 1 year.


RESULTS
The clinical symptoms of acute bilirubin encephalopathy included apnea (2.4%), tachypnea (6.0%), fever (1.2%), irritability (2.4%), lethargy (4.8%), seizures (1.2%) and poor feeding (19.3%). Hyperbilirubinemia was more severe among babies with Rh incompatibility than those with ABO incompatibility. After double-volume exchange transfusion, the TSB levels significantly decreased from 25.8 3.5 to 17.6 4.0 mg/dL. Using logistic regression analysis, we found neonates with blood group incompatibility more often had a reticulocyte count> 7 %, a hemoglobin value< 13 g /dL and a peak TSB at age< 3 days old than the controls (p < 0.01). Furthermore, kernicterus was more common in neonates with blood group incompatibility (9.8 %) than in the controls (0.0%) (p< 0.01).


CONCLUSIONS
This survey depicts the clinical profiles of babies with marked neonatal hyperbilirubinemia with blood group incompatibility. Neonates with blood group incompatibility often develop early-onset, hemolysis-mediated hyperbilirubinemia. Our findings show they are at great risk of kernicterus.
Weng
Yi-Hao
YH
Division of Neonatology, Department of Pediatrics, Chang Gung Children's Hospital, Taipei, Chang Gung University College of Medicine, Taoyuan, Taiwan. yihaoweng@cgmh.org.tw
Chiu
Ya-Wen
YW
D000017:ABO Blood-Group System / Q000276:immunology; D001663:Bilirubin / Q000097:blood; D001724:Birth Weight; D001787:Blood Group Incompatibility; D001812:Blood-Brain Barrier; D003298:Coombs Test; D005260:Female; D006801:Humans; D007231:Infant, Newborn; D007567:Jaundice, Neonatal / Q000097:blood* / Q000209:etiology; D008297:Male; D012189:Retrospective Studies
D000017:ABO Blood-Group System; D001663:Bilirubin