The combination of three independent predictors of positive hemolysis test results—mean corpuscular hemoglobin concentration (MCHC), red blood cell volume distribution width (RDW-CV), and reticulocyte count (RET)%—can be utilized to help improve detection of ABO-hemolytic disease of the fetus and newborn (HDFN), according to findings from a retrospective case-control study conducted in China and recently published in Frontiers in Pediatrics.
Among patients with ABO-HDFN, diagnostic criteria include the following:
- Incompatibility between the mother and the newborn
- Clinical manifestations of neonatal bilirubin abnormalities
- Serologic confirmation of the presence of hemolytic antibodies with the use of three hemolysis tests
Because the hemolysis tests are qualitative, however, false-negative results may be reported. To date, no methods are available to identify which ABO-incompatible neonates who have negative hemolysis test results have undetected low levels of blood group antibodies or to establish whether these low levels of antibodies can cause severe hemolysis.
In an effort to aid in the recognition and management of infants with neonatal jaundice, the researchers sought to evaluate the likelihood of low-level blood group antibody-mediated hemolysis in ABO-incompatible newborns in whom three negative hemolysis tests were reported. They explored the differences in clinical data and laboratory indicators associated with ABO-HDFN among three separate groups of patients as well.
Read more about the testing and diagnosis of HDFN
A total of 892 children with jaundice who were hospitalized in the Neonatology Department of Fujian Maternity and Child Health Hospital, located in Fuzhou, Fujian, China, between June 2020 and May 2023 were enrolled in the study. The participants were divided into three groups, according to maternal and newborn ABO blood type compatibility, as well as their serologic diagnosis of HDFN:
- Group I: ABO compatible; three negative hemolysis tests (n=264)
- Group II: ABO incompatible; three negative hemolysis tests (n=250)
- Group III: ABO incompatible; three positive hemolysis tests (n=378)
All participants were full-term infants with a birth weight of >2500 grams and a gestational age of >37 weeks. The enrolled children all underwent three hemolysis tests to investigate the cause of their jaundice.
Results of the study showed that the frequency of ABO incompatibility was statistically significantly higher among female participants compared with male participants. Additionally, the participants in group II exhibited significantly higher levels of MCV, RDW-SC, alanine aminotransferase (ALT), lactate dehydrogenase, alkaline phosphatase (ALP), and bile acid (BA) than those in group I. No statistically significant differences in MCV, ALT, ALP and BA levels, however, were reported between groups II and III.
MCHC of >359.5 g/L, RDW-CV of >15.95%, and RET of >4.235% were all identified as being independent predictors of positive hemolysis test results (P <.001). In fact, MCHC plus RDW-CV plus RET% produced an area under the curve (AUC) of 0.841.
“[T]he changes in liver function caused by hemolysis must be monitored,” the authors explained. “The combination of these predictors [MCHC, RDW-CV, RET%] can help improve the detection of ABO-HD[F]N and facilitate the management of jaundice,” they concluded.
