Dynamic change of fecal calprotectin in very low birth weight infants during the first month of life

Background: Calprotectin is a cytosolic component of neutrophils. Fecal calprotectin (FC) level is a useful marker for exacerbation of inflammatory bowel disease in children. FC may be a useful marker for necrotizing enterocolitis (NEC).

Objective: To determine normal baseline levels of FC and observe dynamic changes of FC levels over the first postnatal month in very low birth weight (VLBW) infants.

Methods: FC levels of 14 VLBW infants (gestational age 23-30 weeks, birth weight <or=1,500 g) were serially measured in the first postnatal month. Demographics, feeding regimens, antibiotic use, laboratory and x-ray results, and maternal information were recorded. We assessed how FC levels changed over time, varied with nutritional source and differed between sick versus well infants.

Results: FC levels were not related to gestational age or feedings regimen. FC levels tended to decrease with increasing age (p = 0.121) and feeding volumes (p = 0.179). FC levels differed between 'well' and 'sick' infants (122.8 +/- 98.9 vs. 380.4 +/- 246.3 microg/g stool, p < 0.001). FC >350 microg/g stool was noted with signs of gastrointestinal injury, such as bloody stool and bowel perforation. FC levels decreased after initiation of treatments in sick infants who recovered.

Conclusions: FC levels may be a marker for early diagnosis and resolution of gastrointestinal illnesses in VLBW infants. Its utility for early diagnosis and assessment of resolution of NEC should be studied in a larger cohort of VLBW infants.