PYLORIC DUPLICATION CYST IN NEWBORN MALE

Objectives: Enteric duplication cysts (EDCs) are rare congenital malformations formed during the embryonic development of the alimentary tract. EDCs have an incidence of 1 in 4500 births with a slight male predominance. Although EDCs can occur at any point throughout the gastrointestinal tract, they are most commonly reported in the ileum and only around 5-7% are of gastroduodenal origin. Limited literature exists surrounding pyloric duplication cysts, which are extremely rare subtypes.

Methods: We present an extremely rare case of pyloric duplication cyst in a 3-hour-old male diagnosed on prenatal ultrasound and successfully treated with surgical resection.

Results: Our patient was a 3-hour old male born at 35 5/7 weeks gestation who presented with a cystic abdominal mass initially detected on prenatal ultrasound (US). Abdominal US was performed after birth which showed a predominantly hypoechoic well-circumscribed mass in the right lower quadrant with probable trilaminar wall. The mass exhibited a small tubular connection that possibly communicated with existing bowel, suggesting an enteric duplication cyst. Patient was tolerating oral intake without obstructive symptoms and scheduled for surgical intervention. During diagnostic laparoscopy, a five centimeter (cm) mass was seen without liver involvement but potentially attached to the duodenum. A right upper quadrant transverse laparotomy was performed and the cyst was identified at the pylorus with the pylorus splayed but not obstructed by the cyst. The cyst was located at the anteroinferior pylorus, included a common wall, and was clearly proximal to the ampulla of vater. An intraoperative transcystic cholangiogram was performed to confirm that there were no communications with the biliary tree. The pyloric duplication cyst was resected en bloc with the pylorus and a primary hand sewn end-to-end gastroduodenostomy was performed. Final pathology confirmed an enteric duplication cyst with benign gastric tissue and duodenal mucosa without dysplasia or malignancy. The patient’s post-operative course was uncomplicated and patient tolerated oral intake prior to discharge. Patient is now home with family and doing well with appropriate weight gain at his follow-up appointment.

Conclusion: Although limited literature exists surrounding pyloric duplication cysts specifically, enteric duplication cysts are known to become symptomatic early in life and current results of surgical therapy are good. This rare case supports the concept of increased prenatal screenings for potentially earlier diagnoses of EDCs which resulted in earlier surgical treatment with hopes of prevention of future symptoms.