Path: Congenital, Esophagus, Stomach

Question 1

absence of the esophagus (rare)

Answer 1

agenesis

Question 2

incomplete development of the esophagus

Answer 2

atresia

Question 3

usually associated with a fistula connecting the upper and lower esophageal pouches to a bronchus or the trachea

Answer 3

atresia

- occurs most commonly at or near the tracheal bifurcation

Question 4

what does intestinal atresia frequently involve?

Answer 4

duodenum

Question 5

incomplete form of atresia in which the lumen is markedly reduced in caliber as a result of fibrous thickening of the wall

Answer 5

stenosis

- can be acquired as a consequence of inflammatory scarring, such as chronic gastroesophageal reflux

Question 6

when incomplete formation of the diaphragm allows the abdominal viscera to herniate into the thoracic cavity

Answer 6

diaphragmatic hernia

Question 7

when closure of the abdominal musculature is incomplete and the abdominal viscera herniate into a ventral membranous sac

Answer 7

omphalocele

Question 8

similar to omphalocele, except it involves all of the layers of the abdominal wall, from peritoneum to the skin

Answer 8

gastroschisis

Question 9

where is the most common site of ectopic gastric mucosa?

Answer 9

inlet patch (upper third of the esophagus)

Question 10

found in the esophagus or stomach, like inlet patches, these nodules are most often asymptomatic but they produce damage and local inflammation

Answer 10

ectopic pancreatic tissue

Question 11

small patches of ectopic gastric mucosa in the small bowel or colon, may present with occult blood loss due to peptic ulceration of adjacent mucosa

Answer 11

gastric heterotopia

Question 12

blind outpouching of the alimentary tract that communicates with the lumen and includes all three layers of the bowel wall

Answer 12

true diverticulum

Question 13

what are the two most common forms of atresia?

Answer 13

• esophageal atresia

- imperforate anus (most common intestinal atresia), due to failure of cloacal diaphragm to involute

Question 14

what is the most common true diverticulum? where does it occur?

Answer 14

Meckel diverticulum, occurs in the ileum

Question 15

occurs as a result of failed involution of the vitelline duct, which connects the lumen of the developing gut to the yolk sac
- solitary diverticulum extends from the anti-mesenteric side of the bowel

Answer 15

Meckel diverticulum

Question 16

what are the “rule of 2’s” of Meckel diverticula?

Answer 16

• 2% of population
• present within 2 feet of the ileocecal valve
• are approx 2 inches long
• twice as common in males
• more often symptomatic by age 2

Question 17

the mucosal lining of Meckel diverticula may resemble what?

Answer 17

normal small intestine, but ectopic pancreatic or gastric tissue may also be present
- the latter may secrete acid, causing ulceration of adjacent small intestinal mucosa

Question 18

3-5 times more common in males, occurs one in every 300-900 live births

• monozygotic twins have 200-fold increased risk if one twin affected
• dizygotic twins have 20-fold increased risk
• Turner syndrome and trisomy 18 have increased risk
• erythromycin or azithromycin in the first 2 weeks of life has been linked to increased incidence

Answer 18

pyloric stenosis

Question 19

presents between the third and sixth weeks of life as new-onset regurgitation, projectile, non-bilious vomiting after feeding, frequent demands for refeeding

Answer 19

congenital hypertrophic pyloric stenosis

Question 20

when does pyloric stenosis present in adults?

Answer 20

• surgical splitting of the muscularis (myotomy)

- can be acquired as a consequence of antral gastritis or peptic ulcers close to the pyloris

Question 21

10% of cases occur in children with Down syndrome (genetic component present in nearly all cases)
- results when neural crest migration from cecum to rectum is arrested prematurely or when the ganglion cells undergo premature death

Answer 21

Hirschsprung disease (congenital aganglionic megacolon)

Question 22

what is the result of “aganglionosis” in megacolon?

Answer 22

the distal intestinal segment lacks both the Meissner submucosal and the Auerbach myenteric plexus
- coordinated peristaltic contractions are absent and functional obstruction occurs -> resulting in dilation proximal to the affected segment

Question 23

heterozygous LOF mutation in receptor tyrosine kinase RET account for majority of familial cases of what?

Answer 23

Hirschsprung disease

Question 24

how can ganglion cells be identified using immunohistochemical stains?

Answer 24

Ach

- they also have characteristic morphology in hematoxylin and eosin-stains

Question 25

what part of the GI tract is always affected in Hirschsprung disease?

Answer 25

the rectum, but the length of additional segments varies widely

Question 26

how does Hirschsprung disease present in the immediate postnatal period?

Answer 26

failure to pass meconium | - obstruction or constipation follows, often with visible, ineffective peristalsis

Question 27

what are the major threats to life in Hirschsprung disease

Answer 27

enterocolitis, fluid, and electrolyte disturbances, perforation, and peritonitis

Question 28

what is the primary mode of treatment of Hirschsprung disease?

Answer 28

surgical resection of the aganglionic segment, followed by anastomoses of the normal proximal colon to the rectum

Question 29

how does acquired megacolon happen?

Answer 29

Chagas disease, obstruction by neoplasm or inflammatory stricture, toxic megacolon complicating ulcerative colitis, visceral myopathy, or in association with functional psychosomatic disorders

Question 30

what develpps from the cranial portion of the foregut and is recognizable by the third week of gestation?

Answer 30

esophagus

Question 31

high amplitude contractions of the distal esophagus that are due to loss of the normal coordination of inner circular layer and outer longitudinal layer smooth muscle contractions

Answer 31

nutcracker esophagus

Question 32

repetitive, simultaneous contractions of the distal esophageal smooth muscle

Answer 32

diffuse esophageal spasm

Question 33

what is present in many patients with nutcracker esophagus or diffuse esophageal spasm?

Answer 33

lower esophageal sphincter spasm

Question 34

esophageal dysmotility may result in development of small diverticulae where?

Answer 34

immediately above the lower esophageal sphincter

Question 35

impaired relaxation and spasm of the cricopharyngeus muscle after swallowing can result in increased pressure within the distal pharynx and development of what?

Answer 35

Zenker diverticulum | - are uncommon, but typically develop after age 50 and may reach several centimeters in size

Question 36

fibrous thickening of the submucosa and is associated with atrophy of the muscularis propria as well as secondary epithelial damage

Answer 36

esophageal stenosis | - due to inflammation and scarring that may be caused by chronic gastroesophageal reflux, irradiation, or caustic injury

Question 37

idiopathic ledge-like protrusions of mucosa that may cause obstruction - typically occur in women older than 40 and can be assoc with gastroesophageal reflux, chronic graft v. host disease, or blistering skin diseases

Answer 37

esophageal mucosal webs

Question 38

what might accompany webs in the upper esophagus?

Answer 38

iron-deficiency anemia, glossitis, and cheilosis (spoon nails) as part of the Paterson-Brown_Kelly or Plummer-Vinson syndrome

Question 39

semi-circumfrential lesions that protrude less than 5mm, have a thickness of 2-4mm, and are composed of a fibrovascular connective tissue and overlying epithelium

Answer 39

esophageal webs

Question 40

what is the main symptom of esophageal webs?

Answer 40

nonprogressive dysphagia associated with incompletely chewed food

Question 41

circumferential, thicker, and include mucosa, submucosa and occasionally hypertrophic muscularis propria

Answer 41

esophageal rings aka Schatzki rings

Question 42

what are esophageal rings called when they present in the distal esophagus, above the gastroesophageal junction, and are covered by squamous mucosa?

Answer 42

A rings

Question 43

what are esophageal rings called when they present at the squamocolumnar junction of the lower esophagus, and may have gastric cardia-type mucosa on their undersurface?

Answer 43

B rings

Question 44

triad of incomplete LES relaxation, increased LES tone, aperistalsis of the esophagus

Answer 44

achalasia

Question 45

what are the symptoms of achalasia?

Answer 45

dysphagia for solids and liquids, difficulty belching, and chest pain

Question 46

does achalasia warrant surveillance endoscopy?

Answer 46

no, there is not considered great enough risk for esophageal cancer

Question 47

what is the result of distal esophageal inhibitory neuronal (ganglion cell) degeneration?

Answer 47

primary achalasia

Question 48

what does primary achalasia lead to?

Answer 48

increased tone, inability to relax the LES, and esophageal aperistalsis - degenerative changes in the extraesophageal vagus nerve or the dorsal motor nucleus of vagus nerve

Question 49

Trypanosoma cruzi infection causes destruction of the myenteric plexus, failure of peristalsis, and esophageal dilation

Answer 49

secondary achalasia due to Chagas disease

Question 50

the association of HSV1 infection, linkage of immunoregulatory gene polymorphisms, and occasional coexistence of Sjogren syndrome, or autimmune thyroid suggests what?

Answer 50

achalasia may also