This analysis showed that the strongest parameter with a significant discriminative capacity for the development of acute respiratory failure (P/F < 300) was sST2, with an area under the curve (AUC) of 0.861 (p < 0.001), with respect to PESI score (AUC = 0.766, p = 0.005), CRP (AUC = 0.680, p = 0.054), creatinine (AUC = 0.572, p = 0.440), d-dimer (AUC = 0.422, p = 0.407), and serum lactate (AUC = 0.564, p = 0.491). This evidence concerns the gene CRP and acute respiratory failure.