Necrotising enterocolitis (NEC) is a serious complication of prematurity and strikes prematurely in all weight groups. The incidence has been almost unchanged during the latest decades suggesting a limited success with current diagnostic and preventative strategies. Researchers have been looking for novel diagnostic tools to lower the incidence of NEC. Researchers have suggested splitting up NEC in smaller entities to target the preventive strategies, yet no revolutionary tool has been presented. This review is a short overview of the latest knowledge concerning diagnostic strategies.