PADI4 and bacterial infectious disease: PADs are associated with a range of bacterial infections, including their role in endotoxic shock, also relating to pulmonary dysfunction [32,36] and sepsis [33,34], where PADI4 levels have been associated with ICU (intensive care unit) mortality [35], as well as in antibiotic resistance, where roles for PAD2 and PAD4 have been described [39].