KRT1 and infection: Why this relationship was not observed in the case of the triple infection could be explained by the relatively young age of patients belonging to this group compared to other groups (median = 3, min = 1, max = 14 year-old, in K1 + MAD20 + RO33, n = 155; versus median = 4, min = 0.4, max = 40 year-old in other groups, n = 570 Fig. 1c).