Quantitative changes in faecal microflora preceding necrotising enterocolitis in premature neonates.

Quantitative studies of faecal bacterial flora were carried out during the week preceding the clinical onset of 12 episodes of neonatal necrotising enterocolitis. There were considerable quantitative changes in the faecal flora preceding the clinical onset of both definite and possible episodes of necrotising enterocolitis. There was a decline in the numbers of some species from up to 72 hours before the clinical onset of the disease. Enterobacteriaceae were isolated from samples collected during the 48 hours preceding the clinical onset of all four definite episodes of necrotising enterocolitis. These were 'new' isolates in two episodes, and considerably increased numbers in another. The changes that we found are probably the result of changes in intraluminal conditions that precede the clinical onset of necrotising enterocolitis.