The report demonstrated the following: (1) the positive Cnm protein area/total tonsillar area rate was significantly higher in patients with IgAN than in the control (chronic tonsillitis) group; (2) Cnm protein existed in the tonsils, not in the glomerulus, in patients with IgAN; and (3) Cnm protein in the tonsils was associated with urinary protein in patients with IgAN [22]. Here, MTM1 is linked to Recurrent tonsillitis.