From the Guidelines
Necrotizing enterocolitis (NEC) presenting as an incarcerated inguinal hernia is a rare but serious condition that requires immediate surgical intervention, with a clinical presentation that includes abdominal distension, bloody stools, and bilious emesis, and may mimic an incarcerated inguinal hernia. The clinical presentation of NEC that mimics an incarcerated inguinal hernia is characterized by:
- Increased episodes of apnea and bradycardia
- Abdominal distension
- Bloody stools
- Bilious emesis
- Portal venous gas may also be present
- The abdomen may become focally erythematous
- Signs of sepsis, such as thrombocytopenia and neutropenia, may also be present; acidosis may also occur if there is bowel ischemia 1. When encountering this presentation, prompt surgical exploration is necessary with careful reduction of the hernia and assessment of bowel viability. The surgical approach typically involves laparotomy to fully evaluate the extent of intestinal involvement, resection of necrotic bowel segments, and possible creation of a temporary ostomy depending on the severity. Postoperatively, the patient should receive broad-spectrum antibiotics (such as ampicillin, gentamicin, and metronidazole or piperacillin-tazobactam) for 7-14 days, bowel rest with parenteral nutrition, and close monitoring for complications including perforation, sepsis, and short bowel syndrome. This condition occurs when intestinal ischemia and inflammation characteristic of NEC develop within herniated bowel loops, typically in premature infants. The pathophysiology involves a combination of mechanical obstruction from the hernia, compromised blood supply, and bacterial invasion of the intestinal wall. Early recognition is critical as the mortality rate is significant, especially in premature infants. Following the acute management, long-term follow-up should include monitoring for recurrent hernia, intestinal strictures, and nutritional status. It's worth noting that the guidelines for the management of acute abdomen in immunocompromised patients, such as those with neutropenic enterocolitis, recommend a non-operative approach with broad-spectrum antibiotics and bowel rest, reserving surgery for cases with signs of perforation or ischemia 1.
From the Research
Clinical Presentation of Necrotizing Enterocolitis (NEC)
The clinical presentation of NEC can be non-specific and may mimic other surgical conditions, including an incarcerated inguinal hernia. Some of the clinical features of NEC include:
- Superficial mucosal ulceration, submucosal edema, and hemorrhage in the early stages of the disease 2
- Transmural necrosis and bowel perforation in advanced cases 2, 3
- Non-specific symptoms such as feed intolerance, abdominal distension, and vomiting 4
- Pneumatosis intestinalis, fixed bowel loop, pneumoperitoneum, and abdominal wall erythema may also be present 4
NEC Mimicking Incarcerated Inguinal Hernia
There are cases where NEC has been reported to occur after the repair of an incarcerated inguinal hernia, suggesting that surgical stress may be a contributing factor to the development of NEC 5, 6. In these cases, the clinical presentation of NEC may be similar to that of an incarcerated inguinal hernia, making diagnosis challenging.
- A case report described a preterm infant who developed NEC after herniotomy for an incarcerated inguinal hernia, highlighting the importance of considering NEC as a potential cause of clinical deterioration in the postoperative period 6
- Another study reported a case of postoperative NEC following emergency repair of an incarcerated inguinal hernia in an older infant, demonstrating that NEC can occur in older infants as well 5