Meckel's Diverticulum in a Five-Day-Old Neonate: An Unusual Case.

Meckel's diverticulum is a congenital anomaly of the gastrointestinal tract. We report the case of a five-day-old male infant who presented to the pediatric emergency department with lethargy, feeding refusal, grunting, bilious vomiting, and abundant bowel movements. Upon observation, he was hypotonic, jaundiced, and poorly perfused, with cool extremities and a soft abdomen. He was admitted to the neonatal intensive care unit, underwent nasogastric tube insertion, and was placed on nothing by mouth. The imaging studies were not conclusive. Subsequently, he progressed to metabolic acidosis. Due to suspicion of an acute surgical abdomen, he was transferred to a hospital with pediatric surgery capabilities. On day seven of life, he was diagnosed with Meckel's diverticulum complicated by enteritis on exploratory laparotomy and underwent a segmental enterectomy with primary anastomosis. The patient was also diagnosed with late-onset sepsis caused by extended-spectrum beta-lactamase (ESBL)-negative Escherichia coli,and subsequent evaluation revealed a patent foramen ovale with a left-to-right shunt. During hospitalization, the patient remained hemodynamically stable, afebrile, and without respiratory distress, maintaining normal bowel and bladder functions. On the second day of hospitalization in the inpatient ward, the patient achieved full feeding autonomy. He was discharged on postoperative day 17. This case highlights that bilious vomiting in a neonate must always be considered a surgical emergency until proven otherwise. Prompt transfer to a pediatric surgery center can be lifesaving, particularly in geographically isolated regions. Although Meckel's diverticulum is a rare entity in the neonate, it should remain in the differential diagnosis when initial imaging is non-diagnostic. Furthermore, despite the challenge of concurrent late-onset sepsis, targeted antibiotic therapy and appropriate clinical management led to the complete resolution of the infection caused by an ESBL-negative E. coli strain, ultimately resulting in an excellent postoperative outcome.