Necrotising enterocolitis (NEC) is a severe gastrointestinal disease with a mortality of 20–40%, affecting predominantly premature neonates.¹ In the early phase of the disease NEC continues to present a diagnostic challenge for the attending clinician. The signs and symptoms are often non-specific, including gastrointestinal problems such as abdominal distension and feeding intolerance, which are also among the most prevalent presenting features of neonatal sepsis.² The diagnosis is further hampered by the limited diagnostic accuracy of the laboratory and radiological tests currently in use.^3,4

Histopathologically, NEC is characterised by intestinal coagulative or ischaemic necrosis, starting at the mucosa and extending into the submucosa and muscularis externa.¹ We sought a non-invasive test to find evidence of enterocyte cell death in infants with gastrointestinal symptoms suspicious of NEC, in order to differentiate NEC from other neonatal diseases that present with abdominal signs.

Intestinal fatty acid binding protein (I-FABP) has been reported to be a useful plasma marker for early enterocyte cell death.^5,6 The small (14–15 kDa) cytosolic I-FABP is specifically present in mature enterocytes of small and large intestine and is released as soon as cell membrane integrity is compromised. I-FABP is present in very small amounts in the plasma of healthy individuals, probably representing the normal turnover of enterocytes, but levels …