Abstract

BACKGROUND AND OBJECTIVE
Both high and low lymphocyte counts at birth have been associated with adverse outcomes. However, the validity of defining a lymphocyte count as "abnormal" depends on having an accurate reference range. We established a reference range for neonatal lymphocyte counts by using multihospital data and used this to assess previously reported relationships between abnormal counts and early onset sepsis (EOS), intraventricular hemorrhage (IVH), retinopathy of prematurity (ROP), periventricular leukomalacia, and birth asphyxia.
METHODS
We first created a data set that excluded counts from neonates with diagnoses previously associated with abnormal lymphocyte counts. Then the complete data (counts excluded plus included in the reference range) were used to test associations between abnormal counts and EOS, IVH, ROP, periventricular leukomalacia, and outcomes after birth asphyxia.
RESULTS
Lymphocyte counts were retrieved from 40 487 neonates, 10 860 of which were excluded from the reference range. A count >95th percentile was associated with EOS (2.07; 95% confidence interval [CI]: 1.80-2.38) and IVH ≥grade 3 (2.93; 95% CI: 1.83-4.71). A count <5th percentile was associated with EOS (odds ratio:1.24; 95% CI: 1.04-1.48), IVH ≥grade 3 (3.23; 95% CI: 1.95-5.36), and ROP ≥stage 3 (4.80: 95% CI: 2.38-9.66). Among 120 meeting criteria for birth asphyxia, those with a low count and a high nucleated red cell count had higher mortality (37% vs 11%, P = .001), more transfusions (P = .000), and more neurology referrals (P < .01).
CONCLUSIONS
A reference range for lymphocytes can identify neonates with abnormal counts, which can be useful because these neonates are at higher risk for certain adverse outcomes.

Links

Publisher Full Text

Authors

Christensen RD, Baer VL, Gordon PV, Henry E, Whitaker C, Andres RL, Bennett ST

Institution

Women and Newborn’s Clinical Program, Intermountain Healthcare, Ogden, Utah 84403, USA. rdchris4@ihc.com

Source

Pediatrics 129:5 2012 May pg e1165-72

MeSH

Asphyxia Neonatorum
Cerebral Ventricles
Cross-Sectional Studies
Gestational Age
Hospital Mortality
Humans
Infant, Newborn
Infant, Premature, Diseases
Leukomalacia, Periventricular
Lymphocyte Count
Neonatal Screening
Outcome Assessment (Health Care)
Reference Values
Retinopathy of Prematurity
Retrospective Studies
Risk Factors
Sepsis
Statistics as Topic
Utah

Pub Type(s)

Journal Article

Language

eng

PubMed ID

22508916