Gastro & Abdominal Wall (Stats)

Esophageal atresia — incidence and associations

Incidence: 1:5,000 on the ultrasound slide; another slide states 1:3,000-4,500 births. 80-90% have a distal TEF. Associated with T13, T18, T21, VACTERL, and other GI/cardiac defects.

Duodenal atresia — incidence and associations

Incidence: 1:10,000. About 30% associated with T21; 50% have other congenital anomalies; cardiac defects in 34%; 65% have a karyotypic abnormality or associated malformation.

Jejunal atresia — important statistics

No incidence number provided in the slides. Atresia accounts for about 95% of jejunoileal obstructions; stenosis accounts for the remaining 5%.

Anorectal atresia — incidence and associations

Incidence: 1:1,500-5,000 live births. 3-4% associated with T18 or T21. Other defects, mainly urogenital, vertebral, and CNS anomalies, occur in up to 70%.

Hirschsprung disease — incidence and key association

Described as rare; no specific incidence provided. Congenital absence of ganglion cells causes impaired peristalsis and megacolon. Newborn may fail to pass meconium within 48 hours.

VACTERL association — incidence and statistics

Incidence: 1:10,000-40,000 newborns. Usually at least 3 features. 50-80% have TEF. About 90% of cases are sporadic.

Echogenic bowel — incidence and associations

Found in 1-4% of second-trimester pregnancies. Associated with CF, T21, swallowed blood, viscous meconium, bowel perforation, and decreased water content.

Cystic fibrosis — incidence and inheritance

Incidence: 1:3,500 live births. Autosomal recessive; both parents carriers = 25% affected, 50% carrier, 25% neither. Associated with echogenic or dilated bowel/meconium ileus.

Cystic fibrosis — carrier frequency

About 1:19 Americans are carriers. Slide populations: European Caucasian/Ashkenazi Jewish 1:29; Hispanic American 1:46; African American 1:61; Asian American 1:90.

Fetal abdominal calcifications — liver incidence

Liver calcifications are identified in 1:1,750 second-trimester ultrasound examinations. Isolated hepatic calcifications generally have a favorable outcome and need no intervention.

Ovarian cysts — incidence and associations

Most common fetal abdominal cyst. Incidence: 1:2,600. Occurs in female fetuses, usually in the third trimester, especially after 28 weeks. Most resolve spontaneously.

Choledochal cysts — types and statistics

There are 5 types. Type I is the most common, accounting for 80-90%, and is the only form described as prenatally diagnosed in the slides.

Intestinal duplication cyst — incidence and associations

No incidence or associated-anomaly percentage provided. Located in the middle abdomen near the intestine; appears as an intestinal wall-like structure.

Mesenteric cyst — incidence and associations

Described as rare; no specific incidence provided. Can occur anywhere from duodenum to rectum and may extend into the retroperitoneum. Usually requires surgical removal.

Gastroschisis — incidence and associations

Incidence: 1:2,000. Associated anomalies are rare. Bowel may become ischemic or die; intestinal obstruction may occur. Increased MSAFP: 4-5 MoM.

Omphalocele — incidence and associations

Incidence: 1:4,000. Associated anomalies in about 50%. T13/T18 in 33%; Beckwith-Wiedemann syndrome in 7%. Check the heart; cardiac anomalies are emphasized in the slides.

Umbilical hernia — incidence and associations

No incidence or associated-anomaly statistics provided. Intestine herniates through a small opening near the umbilicus; covered by skin and typically small.

Meckel diverticulum — important facts

No incidence provided. Most common midgut malformation. Remnant of the proximal yolk stalk; appears as a fluid-filled finger-like sac about 5 cm long projecting from the ileum.

Pentalogy of Cantrell — incidence and associated defects

Prevalence: 5.5 per 1 million neonates. Includes 5 defects: omphalocele, anterior diaphragmatic hernia, sternal cleft, ectopia cordis, and intracardiac defect.

Limb-body wall complex — incidence and associations

Incidence: 1:14,000. Severe body-wall defects, short or absent umbilical cord, eviscerated organs adherent to amnion/placenta, severe scoliosis, and limb defects. Amniotic bands may be present in only half of cases.