From the Guidelines
Necrotizing enterocolitis (NEC) is graded using Bell's staging criteria, which helps guide management based on disease severity, and the most recent evidence suggests that prevention strategies, including the use of probiotics, are crucial in reducing the risk of NEC in preterm infants. The grading of NEC is as follows:
- Stage I (suspected NEC) presents with mild systemic illness, feeding intolerance, and minimal radiographic findings, requiring bowel rest, broad-spectrum antibiotics (typically ampicillin, gentamicin, and metronidazole or clindamycin) for 3-5 days, and close monitoring 1.
- Stage II (definite NEC) shows moderate systemic illness with pneumatosis intestinalis on imaging, requiring NPO status for 7-14 days, parenteral nutrition, and antibiotics for 10-14 days.
- Stage III (advanced NEC) presents with severe illness, metabolic acidosis, hypotension, and pneumoperitoneum, requiring immediate surgical consultation, fluid resuscitation, vasopressor support if needed, and possible surgical intervention including peritoneal drainage or laparotomy with bowel resection.
Clinical presentation varies from subtle feeding intolerance and abdominal distention to severe sepsis with respiratory failure and shock. Management principles include:
- Prompt cessation of feeds
- Gastric decompression
- Fluid resuscitation
- Antibiotics
- Correction of coagulopathy and electrolyte abnormalities
- Careful monitoring of laboratory values and serial abdominal examinations
Prevention strategies include:
- Preferential use of human milk
- Standardized feeding protocols
- Probiotics in high-risk infants, with the most recent evidence suggesting that combinations of Lactobacillus spp and Bifidobacterium spp, or B animalis subsp lactis, or L reuteri, or L rhamnosus, are beneficial in reducing the risk of NEC in preterm infants 1
- Judicious antibiotic use
NEC primarily affects premature infants due to intestinal immaturity, altered microbiome, and impaired mucosal barrier function, which together lead to intestinal inflammation and injury. The survival rate for NEC is close to 95% unless NEC involves the entire bowel, which occurs approximately 25% of the time and is associated with a mortality rate of 40%–90% 1. Nonoperative management of NEC is successful approximately 70% of the time, and peritoneal drainage may be used instead of immediate operation when bowel perforation occurs in very low birth weight neonates 1.
From the Research
Grading of Necrotizing Enterocolitis (NEC)
- NEC is typically graded using Bell's staging, which takes into account clinical and imaging manifestations 2
- The grading system helps clinicians to determine the severity of the disease and guide treatment decisions
Clinical Presentation of NEC
- NEC is characterized by inflammatory disease of the gastrointestinal tract, with symptoms ranging from transient feed intolerance to life-threatening complications such as septicemia and disseminated intravascular coagulation 3
- Clinical features may include pneumatosis intestinalis, fixed bowel loop, pneumoperitoneum, and abdominal wall erythema 3
- The disease predominantly affects premature neonates, but can also occur in term neonates 3
Management of NEC
- Medical management includes broad-spectrum antibiotics, gut rest, and total parental nutrition 4
- Surgical intervention is typically reserved for severe cases, such as those with intestinal perforation 4
- The use of additional antibiotics providing anaerobic coverage, such as metronidazole, may be considered in patients with surgical NEC 5
- There is no clear evidence-based consensus on empiric antibiotic strategies or surgical timing, and well-conducted, appropriately sized comparative trials are needed to make evidence-based recommendations 5
- In patients with NEC without perforation, medical management may be associated with a lower mortality rate compared to surgical intervention 3
- The surgical management of NEC may involve peritoneal lavage, bowel resection with enterostomy formation, or primary anastomosis of bowel in limited NEC 4