THE RELATIONSHIP BETWEEN NEONATAL
LEUKEMOID REACTION AND CHRONIC LUNG DISEASE IN LOW-BIRTH-WEIGHT INFANTS
Zanardo V, Savio V, Franzoi M
Department of Pediatrics,
Padua University, Padua, Italy
Objective:
Leukemoid reaction (LR) in low-birth-weight infants is a rare, recently
documented phenomenon, implicated in the sequence of multiorgan
inflammatory diseases of preterm infants. The aim of the present research
was to establish whether a neonatal LR is related to chronic lung disease
(CLD) of prematurity development.
Methods:
The design was a retrospective study of all premature infants (born <31
weeks’ gestation) admitted to the neonatal intensive care unit (NICU) over
a period of 3 years, from January 1998 to December 2000. The infants who
developed CLD formed the study group, while the remainder without pulmonary
sequelae, matched for gestational age, formed the control group. LR was
considered a white blood cell (WBC) count > 40000/mm3.
All those identified had a standardized evaluation consisting of karyotype
analysis, bacterial cultures, TORCH, and serial complete blood cell counts
until LR remitted.
Results:
Five of 50 CLD infants studied demonstrated WBC counts >
40000/mm3, with an incidence of 10%, while no control preterm
infants presented neonatal LR; the estimated number difference is
statistically significant (Bayesian statistics, p<0.001). There was
no other significant association demonstrated between maternal or neonatal
variables and LR, including chorioamnionitis, sepsis and the use of antenatal
steroids.
Conclusion:
Our findings provide further data for the identification of prematures
exposed to proinflammatory cytokines in utero; the injury responsible for
CLD in a subset of prematures may begin with a transient LR.