“…These complications may occur simultaneously or sequentially over the disease course. They are thought to derive from dysregulated innate and adaptive cellular activation responses due to underlying pathogenetic mechanisms that affect the maintenance of tolerance(14,15,16). As a consequence, lung complications in this group are more severe than those of the �irst group and encompass, in addition to bronchiectasis, interstitial and parenchymal lung disease (ILD).These two distinct clinical phenotypes likely result from distinct genetic defects causing CVID, falling broadly into two categories: those that almost exclusively affect B cell development, differentiation, activation, and/or survival, such as genes encoding for the cluster of differentiation 19, 20, 21, or 27 (�irst group), and those that control/affect crosstalk between B and T cells (i.e mutations in LRBA, CTL-4, NFKB1, NFKB2, PIK3CD, STAT3), causing immune dysregulation ultimately leading to ILD (second group)…”