What chest X-ray finding is characteristic of transitional tachypnea?

Transitional tachypnea, also known as respiratory distress syndrome in the immediate newborn period, is typically caused by retained fetal lung fluid, particularly in infants delivered via cesarean section without prior labor. The chest X-ray findings that are characteristic of this condition include perihilar streaking, which refers to linear opacities that appear around the hilar regions of the lungs.

This specific finding correlates with the presence of pulmonary edema due to the fluid retention, leading to the characteristic appearance of streaking on the X-ray. As the fluid is gradually reabsorbed over the first few days after birth, the tachypnea usually resolves.

In contrast, other findings such as ground glass opacities are more associated with conditions like neonatal respiratory distress syndrome (NRDS) due to surfactant deficiency, while coarse infiltrates and nonspecific patchy infiltrates do not specifically point to transitional tachypnea and can be related to other underlying lung pathology. Thus, the identification of perihilar streaking is key in diagnosing transitional tachypnea and distinguishes it from other respiratory conditions in neonates.