Neonatal necrotizing enterocolitis

Abstract

Neonatal necrotizing enterocolitis (NEC) is a highly lethal disease of the newborn infant, which has aroused great interest in the past decades. It is characterized by ischemic necrosis of the intestinal wall, frequently leading to perforation and death. Unlike most neonatal emergencies, it is acquired and can be successfully treated without operation in most cases. The etiology is still obscure and is considered to be multifactorial. Intestinal ischemia, infections, cow's milk, and hyperosmolar feeding are among the impotant factors associated with the pathogenesis of NEC in the newborn. Many other factors are also related to the occurrence of this disease but some of them are still controversial. The general opinion is that requiring a background of mucosal ischemia and damage; the presence of both intestinal bacteria and enteric feedings appear to be significant etiologic factors. The important pathologic lesion is the mucosal damage and necrosis involving mostly the ileum and colon except the duodenum. Perforations usually occur in the ileocecal region where the intestinal wall is extremely thin. Necrotizing enterocolitis in the newborn mostly affects the low-birth-weight infants, although its occurrence in full-terms has also been reported. Clinically, it is characterized by abdominal distension, hemato chezia, and pneumatosis intestinalis. Abdominal roentgenography is by far the most specific and sensitive test for confirming the diagnosis. In the attempt to make an early diagnosis it was suggested that an increased concentration of fecal reducing substances using the Clinitest method has an obvious merit in the detection of clinical manifestations in 'at risk' babies. In spite of a better treatment and management, the mortality remains considerably high. An early and aggressive therapy which demands an acute awareness of the significant symptom complexes, particularly in prematures, is of utmost importance if the mortality is to be improved. Medical treatment is the method of choice which includes nasograstric suction, intravenous fluid therapy, and systemic antibiotic for at least a 10-day period. With the improvement of medical treatment and management, there seems to be less and less patients requiring surgical intervention. Many trials have been conducted in the prevention of either intestinal perforation or of the incidence of neonatal-necrotizing enterocolitis. All these await ongoing studies since a definite conclusion still cannot be obtained. Due to the relatively high incidence of low-birth-weight infants in developing countries, the possibility of necrotizing enterocolitis in the neonatal emergency cases has to be always taken into account.