A 4-week-old infant is brought to the emergency department by his parents with violent vomiting. It started about 3 days ago and has slowly gotten worse. He vomits after most feedings but seems to keep some formula down. His mother notes that he is eager to feed between episodes and seems to be putting on weight. Other than an uncomplicated course of chlamydia conjunctivitis, the infant has been healthy. He was born at 39 weeks gestation via spontaneous vaginal delivery. He is up to date on all vaccines and is meeting all developmental milestones. The physical exam is significant for a palpable mass in the right upper quadrant. What is the first-line confirmatory diagnostic test and associated finding?

Abdominal ultrasound; elongated pyloric channel and muscle hypertrophy

Barium upper GI series; GE junction and portion of the stomach in thorax

Air enema; filling defect and coil spring sign

Barium upper GI series; bird beak sign and corkscrewing

Abdominal X-ray; ‘double bubble’ sign

A 52-year-old man comes to the physician because of a 3-month history of upper abdominal pain and nausea that occurs about 3 hours after eating and at night. These symptoms improve with eating. After eating, he often has a feeling of fullness and bloating. He has had several episodes of dark stools over the past month. He has smoked one pack of cigarettes daily for 40 years and drinks 2 alcoholic beverages daily. He takes no medications. His temperature is 36.4°C (97.5°F), pulse is 80/min, and blood pressure is 110/70 mm Hg. Abdominal examination shows epigastric tenderness with no guarding or rebound. Bowel sounds are normal. Which of the following treatments is most appropriate to prevent further complications of the disease in this patient?

Amoxicillin, clarithromycin, and omeprazole

Intravenous vitamin B12 supplementation

Fundoplication, hiatoplasty, and gastropexy

Distal gastrectomy with gastroduodenostomy

A 4700-g (10.3-lb) male newborn is delivered at 37 weeks' gestation to a 30-year-old woman, gravida 2, para 1. Apgar scores are 7 and 8 at 1 and 5 minutes, respectively. The newborn appears pale. Temperature is 37°C (98.6°F), pulse is 180/min, and blood pressure is 90/60 mm Hg. Examination in the delivery room shows midfacial hypoplasia, infraorbital creases, and a large tongue. The right side of the body is larger than the left. Abdominal examination shows that the abdominal viscera protrudes through the abdominal wall at the umbilicus; the viscera are covered by the amniotic membrane and the peritoneum. The liver is palpated 2–3 cm below the right costal margin. Fingerstick blood glucose concentration is 60 mg/dL. Ultrasonography of the abdomen shows enlarged kidneys bilaterally. In addition to surgical closure of the abdominal wall, which of the following is the most appropriate next step in management?

Serial abdominal ultrasonography

Serum 17-hydroxyprogesterone measurement

A 28-year-old male presents to his primary care physician with complaints of intermittent abdominal pain and alternating bouts of constipation and diarrhea. His medical chart is not significant for any past medical problems or prior surgeries. He is not prescribed any current medications. Which of the following questions would be the most useful next question in eliciting further history from this patient?

"Can you tell me more about the symptoms you have been experiencing?"

"Does the diarrhea typically precede the constipation, or vice-versa?"

"Is the diarrhea foul-smelling?"

"Please rate your abdominal pain on a scale of 1-10, with 10 being the worst pain of your life"

"Are the symptoms worse in the morning or at night?"

Congenital abdominal wall defects

👶 Belly's Big Debut

Two major ventral wall defects from failed embryologic closure. The key difference is the presence or absence of a protective sac covering the herniated viscera.

Feature	Gastroschisis	Omphalocele
Location	Right of umbilicus	Midline, through umbilicus
Covering	Absent; bowel exposed	Sac (amnion, peritoneum)
Cord	Normal abdominal insertion	Inserts onto the sac
Etiology	Vascular insult	Failure of gut to return
Anomalies	Rare; bowel atresia	Common (>50%); cardiac, trisomies

👶 Pathology - Why It Pops Out

Omphalocele: Failure of lateral body wall folds to fuse.
- Herniation of abdominal contents through the umbilical ring.
- Contents are covered by a sac (peritoneum & amnion).
Gastroschisis: Full-thickness defect lateral to the umbilicus (usually right).
- Likely due to a vascular accident (e.g., involution of the right omphalomesenteric artery).
- Bowel herniates with no covering sac, exposed to amniotic fluid.

⭐ Omphalocele is a midline defect often associated with other midline defects (cardiac) and chromosomal abnormalities (Trisomies 13, 18).

Embryology of Gastroschisis and Omphalocele

👶 Clinical Manifestations - The Great Divide

Feature	Omphalocele	Gastroschisis
Location	Midline, failure of umbilical ring closure. Defect >4 cm.	Paraumbilical (right > left), likely vascular insult. Defect <4 cm.
Covering Sac	✅ Present (amnion, peritoneum), shiny, gray.	❌ Absent; bowel directly exposed to amniotic fluid.
Contents	Bowel, liver, spleen.	Usually only midgut loops, stomach. Liver is rare.
Cord Insertion	At the apex of the sac.	Normal, lateral to the defect.
Bowel Appearance	Protected, normal.	Inflamed, edematous, matted, thickened ("peel").
Maternal AFP	↑	↑↑ (significantly higher due to exposed bowel).
Associated Anomalies	Common (~50-70%); cardiac, trisomies (13, 18).	Rare (~10-15%); intestinal atresia/stenosis.

🛠️ Management - The Fix-It Plan

Immediate Stabilization (Both):

Cover defect with sterile, saline-soaked gauze & plastic wrap.
IV fluids for resuscitation & broad-spectrum antibiotics.
NG/OG tube for decompression.
Maintain temperature in a radiant warmer.

Surgical Strategy: Goal is tension-free closure.

Gastroschisis: Urgent repair. If primary closure isn't feasible, a silo is placed for staged reduction.
Omphalocele: Repair after full anomaly workup. Staged repair or "paint and wait" technique for giant defects.

Gastroschisis silo placement and reduction

⭐ Gastroschisis is a surgical emergency due to exposed, inflamed bowel. Omphalocele repair is often delayed to evaluate for severe associated anomalies (e.g., cardiac defects, Beckwith-Wiedemann), which dictate overall prognosis.

⚡ Biggest Takeaways

Gastroschisis is a full-thickness defect right of the umbilicus with no covering sac; bowel is exposed and inflamed.

Omphalocele is a midline defect where herniated viscera (often including liver) are covered by a sac.

Omphalocele is highly associated with other anomalies (cardiac, trisomies 13/18, Beckwith-Wiedemann).

Gastroschisis is typically an isolated defect, resulting from a vascular accident.

Both present with elevated maternal serum AFP.

Initial management involves sterile wrapping, fluid resuscitation, and NG tube decompression.