[Neonatal leukemoid reaction caused by prenatal corticoid administration?]

Area of Science:

• Neonatal Medicine
• Pediatric Hematology
• Perinatology

Background:

• Leukemoid reactions, characterized by extremely high white blood cell counts, are rare in neonates.
• Distinguishing reactive leukocytosis from leukemia is crucial in the neonatal period.
• Preterm infants are susceptible to various physiological challenges.

Observation:

• A preterm infant presented with a significant leukemoid reaction, peaking at 112,000 leukocytes/microliter on day 4.
• Leukocyte counts normalized by the second week of life without specific intervention.
• Extensive investigations ruled out common causes of neonatal leukocytosis.

Findings:

• The transient leukemoid reaction in this preterm infant normalized spontaneously.
• No underlying infectious, malignant, or genetic cause for the leukocytosis was identified.
• Maternal administration of corticosteroids to prevent respiratory distress syndrome was noted.

Implications:

• This case suggests a possible association between maternal corticosteroid exposure and neonatal leukemoid reactions.
• Further research is warranted to explore the mechanisms linking antenatal corticosteroids to transient neonatal leukocytosis.
• Clinical vigilance is advised for preterm infants born to mothers receiving corticosteroids, monitoring for similar hematological changes.