For 2 AAE-C1-INH patients (P1 and P2), the diagnosis of MGUS (IgM κ and IgG λ) was made shortly after symptoms’ onset, while the male patient (P1) developed an indolent B-cell-lymphoma 3 years after the first symptoms of AAE-C1-INH began. Here, SERPING1 is linked to acquired angioedema.