Development of an abbreviated symptom score for the neonatal abstinence syndrome.

OBJECTIVE: We sought a shortened MOTHER neonatal abstinence syndrome (NAS) and Finnegan score that would retain comparable performance characteristics of the full instrument. STUDY DESIGN: Retrospective cohort. RESULTS: In total, 124,170 MOTHER NAS scores between August 2007 and May 2016 from 775 infants (≥36 weeks) were examined. Classification and regression tree model identified the most important subsets of the scored variables. A 9-element shortened scale yielded >90% sensitivity and specificity to predict clinical endpoints based on the full 19-element MOTHER NAS score. Conversion of the data sets to the Finnegan score, and applying the same procedure resulted in a nine-element score with similar performance characteristics. CONCLUSION: Shortened scoring instruments were identified with the high-predictive power for clinical endpoints based on the 19-element full MOTHER NAS score. There was no substantial variation in performance for age, supporting the current practice of utilizing a single scoring tool regardless of postnatal age.

Transfer of antibodies directed to paternal major histocompatibility class I antigens from pregnant mice to the developing fetus.

The placental transmission of antibodies directed toward paternal MHC Class I antigens to the developing fetus was studied to assess their effect on the expression of MHC antigens during fetal development and on the development of immune function. 125I-monoclonal anti-paternal MHC antibodies injected i.v. into pregnant mice on day 15 of gestation were efficiently transferred to the fetus within 24 hr in a dose-dependent manner. Biochemical studies on the transferred radioactivity showed that intact antibodies accumulated in the fetus for up to 3 days after antibody injection. During the same period, antibodies were eliminated from the maternal system. The transfer and accumulation of anti-MHC antibodies were independent of the MHC haplotype of the fetus. The pathway of antibody transfer and the localization of transmitted antibodies in the fetus were studied by autoradiographic analysis of the entire fetoplacental unit 24 hr after the injection of anti-paternal MHC antibodies. Our results indicate that antibodies are transferred by way of the placenta and yolk sac, and reach the fetus predominantly via the circulation. Within the embryo proper, the highest levels of antibody were found in the order of blood greater than thymus greater than fetal liver. Most other fetal organs, with the exception of brain and cartilage, showed antibody accumulation, but to a lesser extent. This pattern of antibody distribution over different tissues was similar for allogeneic and syngeneic fetuses. These findings demonstrate that various fetal tissues, including developing lymphoid cells can be directly exposed to the maternally transmitted anti-MHC antibodies, with possible functional consequences on the development of the fetal immune system.