Objective To evaluate longitudinally human β-defensins (hβD), fecal calprotectin and TNF-α in stools of preterm and term newborns, in relation to caesarean section versus vaginal delivery and gestational age.

Patients and Methods In stool samples of 37 preterm newborns (G1) (mean gestational age 31.25, 29 caesarean section, eight vaginal delivery) and 30 term newborns (G2) (mean gestational age 39.27, 20 caesarean section, 10 vaginal delivery) on days 15 and 30 hβD and TNF-α (pg/mg feces) (Immunodiagnostics) and fecal calprotectin (μ/mg feces) (Eurospital) were analysed. Statistical analysis: SAS. For repeated measures: analysis of variance test. Relation with gestational age: regression model.

Results Mean fecal calprotectin increased in G1 and G2 from day 15 (G1 185.84 ± 101; G2 227.29 ± 87, p<0.001) to day 30 (G1 201 ± 90; G2 287.11, p<0.001).The increase was higher in vaginal delivery with respect to caesarean section (p<0.01) and positively correlated with gestational age (p = 0.01). Mean TNF-α did not increase from day 15 (G1 47.04 ± 23; G2 35.82 ± 14) to day 30 (G1 53.60 ± 29; G2 34.59 ± 12) and was negatively correlated with gestational age (p<0.001). Mean hβD increased both in G1 and G2 from day 15 (G1 0.79 ± 0.3; G2 1.08 ± 0.6) to day 30 (G1 1.35 ± 1; G2 1.25 ± 1, p<0.001).

Conclusions hβD, fecal calprotectin and TNF-α are present in intestinal lumen in preterm and term newborns. Fecal calprotectin and hβD increase in the first month of life; fecal calprotectin is higher in term newborns and in vaginal delivery, perhaps influenced by intestinal colonisation. TNF-α is higher in preterms, and could represent a protective mechanism against intestinal infections.