During hospitalisation, patients with pneumonia had significantly higher IL-10 (4.42 (3.89-4.95), <i>p</i> > 0.001) and neutrophil oxidative burst capacity (1.52 (0.96-2.09), <i>p</i> > 0.001) at day 1, CYFRA21-1 at day 2 (0.43 (0.10-0.76), <i>p</i> = 0.01), IL-6 at day 3 (3.11 (2.66-3.55), <i>p</i> > 0.001) and day 5 (0.57 (0.05-1.09), <i>p</i> = 0.03) and CRP at day 4 (1.87 (1.51-2.24), <i>p</i> > 0.001), day 5 (1.38 (1.03-1.72), <i>p</i> > 0.001), day 6 (0.74 (0.42-1.06), <i>p</i> > 0.001) and day 7 (0.87 (0.12-1.63), <i>p</i> = 0.02). Here, CRP is linked to susceptibility to pneumonia measurement.