This study, thanks to its multicenter design, will clarify the role(s) of sPLA2 and its pathway modulators in several paediatric and neonatal forms of lung injury. In fact, enough evidence is available to indicate sPLA2, or at least some of its subtypes, as a key point in the pathophysiology of certain critical respiratory diseases. Inflammation is a complex process and is essential in many of these conditions: sPLA2 might be the main crossroad between inflammation and surfactant catabolism. Since this latter is surely an important component of some clinical situations, sPLA2 is worth to be studied in its metabolic and genetic issues, trying to correlate them to the clinical pictures.