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

NEC is one of the most common ,deadliest and enigmatic intestinal problems encountered mostly in premature infants. The precise pathophysiology of NEC is unclear ,but major factors thought to play an important role include an immature intestine ,an inflammatory response to intestinal microbes,enteral feedings and intestinal ischemia-reperfusion injury.Diagnosis of NEC is not easy clinically and up to now there is not a simple laboratory test to differentiate NEC at an early stage from other conditions in the neonate.

Arginine is the substrate for NO production in the gut and its deficiency may cause vasoconstriction and gut injury and thus predispose to NEC. In previous studies arginine supplementation was found to reduce the incidence of NEC in premature infants but more studies are needed for the use of arginine supplementation for the prevention of NEC.

The investigators aim is to measure the fecal calprotectin in very low birth weight (VLBW) infants during the first month of life as an inflammatory marker of the bowel and evaluate whether premature infants receiving arginine supplements had lower calprotectin values compared to the premature infants that did not .

The investigators hypothesize that arginine supplementation in preterm infants reduces the inflammation of the gut which will be shown by the lower fecal calprotectin values of the premature infants receiving arginine supplementation.

Inclusion Criteria:

• preterm neonates born at Alexandra hospital during the study period
• < 34 weeks gestational age
• < 1500gr birth weight

Exclusion Criteria:

• major congenital abnormalities
• inborn errors of metabolism
• parents not consent