An Overview on Relation between Lactate Dehydrogenase and Transient Tachypnea of The Newborn

Abstract

Background: Transient tachypnea of the newborn (TTN) is a self-limited respiratory condition commonly seen in term and late preterm neonates, typically occurring within the first few hours of life. It is characterized by rapid breathing due to delayed clearance of fetal lung fluid, leading to mild-to-moderate respiratory distress. TTN is usually benign but can be difficult to distinguish from more severe respiratory conditions in the early neonatal period. Lactate dehydrogenase (LDH) is a cytoplasmic enzyme found in most body tissues, including the lungs, and is released into the bloodstream in response to cellular damage or increased metabolic stress. Elevated serum LDH levels have been proposed as a potential biomarker of pulmonary inflammation or injury, which may be present even in non-severe neonatal respiratory conditions. Several studies have explored the relationship between LDH levels and neonatal respiratory diseases, including TTN. Some findings suggest that neonates with TTN may exhibit elevated LDH levels compared to healthy newborns, likely reflecting transient pulmonary stress or fluid retention in the alveoli. However, LDH levels in TTN are generally lower than those observed in more serious conditions like neonatal pneumonia or respiratory distress syndrome (RDS). Thus, LDH may help in differentiating TTN from other causes of neonatal respiratory distress, although its utility remains adjunctive and not diagnostic on its own. Understanding this relationship could assist clinicians in early risk stratification, reduce unnecessary antibiotic use, and guide further investigations when managing newborns presenting with tachypnea.