Pleural effusions in the neonate.

Purpose of Review: This review highlights the pathophysiological mechanisms, incidence, clinical features, as well as the diagnosis and treatment of pleural effusions in the neonate.
Recent Findings: Pleural effusions are rare except in hydropic neonates. Elevated pleural fluid/serum immunoglobulin G ratio may be a diagnostic marker for congenital chylothorax in utero. Chylothorax may be congenital or acquired. Hydrothoraces may appear at any time during the neonatal period and are related to infectious and noninfectious aetiologies. Haemothorax is defined as the presence of blood in the pleural space. Parenteral nutrition leakage may occur in a newborn with a venous central catheter leading to an effusion that looks like a chylothorax. The value of elevated pleural fluid N-terminal pro-brain natriuretic peptide levels as a marker of congestive heart failure is not yet established in neonates. More recently, in cases of chylothorax that did not resolve with drainage and bowel rest, the use of somatostatin or its analogue octreotide has been described with success. If conservative management fails after 5 weeks, surgical intervention is indicated.
Summary: Clinicians must be aware of the wide range of disorders causing pleural effusions, the different types and clinical presentations, differential diagnosis, and how to treat each specific case.