MUC1 and COVID-19: Also, in non-COVID-19 group CT score was higher in patients with KL-6 > 400 U/mL patients than in patients with KL-6 ≤ 400 U/mL patients, although this difference was not statistically significant (5.00, IQR:1.75–8.00 versus 3.50, IQR:2.00–6.50, p-value 0.716) (Fig. 5b).