TNF and acute respiratory distress syndrome: were prevalent in bronchoalveolar lavage fluid from ARDS patients and were significantly correlated with serum TNF-α concentrations, a critical mediator of the septic stress reaction and a predictor of patient mortality (33), while the class Gammaproteobacteria included pathogens such as Escherichia coli and Klebsiella spp., which were normally found in small numbers but have the potential to overgrow and dominate the intestinal tract during dysbiosis (34).