Chapter 17: GIT- Congenital Abnorm-Atresia, Fistulae & Duplications

Question 1

Describe the GIT.

Answer 1

The gastrointestinal (GI) tract is a **hollow tube** extending **from the oral cavity to the anus** that
**consists of anatomically distinct segments,** including the _*esophagus, stomach, small intestine,
colon, rectum, and anus.*_

Each of these segments has unique, complementary, and highly integrated functions, which together serve to regulate the intake, processing, and absorption of
ingested nutrients and the disposal of waste products

Question 2

The regional variations in structure and
function are reflected in diseases of the GI tract, which often affect one or another segment
preferentially.

Accordingly, following consideration of several important congenital abnormalities,
the discussion will be organized anatomically. Disorders affecting more than one segment of the
GI tract, such as Crohn disease, will be discussed with the region that is involved most
frequently.

Question 3

Depending on both the nature and timing of the insult, a variety of developmental anomalies can affect the GI tract.

Importantly, because many organs develop simultaneously during embryogenesis, the presence of congenital GI disorders should prompt evaluation of other organs.

Some defects are commonly associated with GI lesions.

Question 4

To where can Atresia, fistulae, and duplications may occur along the GIT?

Answer 4

any part of the GI tract.

Question 5

If Atresia, fistulae, and duplications present within the esophagus, when are they discovered and why?

Answer 5

shortly after birth, usually because they cause regurgitation during feeding.

These must be corrected promptly, since they are incompatible with life.

Question 6

What is atresia of the esophagus?

Answer 6

Absence, or agenesis, of the esophagus is extremely rare, but atresia, in which development is
incomplete, is more common.

Question 7

Describe esophageal atresia.

Answer 7

thin, noncanalized cord replaces a segment of esophagus, causing a mechanical obstruction ( Fig. 17-1A ).

Proximal and distal
blind pouches connect to the pharynx and stomach, respectively.

Question 8

Atresia occurs most commonly where?

Answer 8

at or near the tracheal bifurcation and is usually associated with a fistula connecting the upper
or lower esophageal pouches to a bronchusor thetrachea (17–1B).

Question 9

Fistulae in the esophagus can lead to what?

Answer 9

• aspiration,
• suffocation,
• pneumonia, and
• severe fluid and electrolyte imbalances ( Fig. 17-1B,C).

Question 10

Esophageal atresia is associated with what?

Answer 10

• congenital heart defects,
• genitourinary malformations,
• and neurologic disease

Question 11

Which is more commonly affected by atresia, esophagus or intestine?

Answer 11

Intestinal atresia is less common than esophageal atresia

Question 12

Intestinal atresia is less common than esophageal atresia but frequently involves which segment?

Answer 12

the duodenum and is characterized by a segment of bowel lacking a lumen.

Question 13

Intestinal atresia is less common than esophageal atresia but frequently involves the duodenum and is characterized by what?

Answer 13

segment of bowel lacking a lumen.

Question 14

Answer 14

FIGURE 17-1 Esophageal atresia and tracheoesophageal fistula.

• A, Blind upper and lower esophageal segments.
• B, Blind upper segment with fistula between lower segment and trachea.
• C, Fistula between patent esophagus and trachea. Type B is the most common.

Question 15

What is stenosis?

Answer 15

Stenosis is an incomplete form of atresia in which the lumen is markedly reduced in caliber as a
result of fibrous thickening of the wall, resulting in partial or complete obstruction.

Question 16

Stenosis may involve any part of the GI tract, although the which are most often affected?

Answer 16

esophagus and small intestine

Question 17

What is the most common form of congenital intestinal atresia?

Answer 17

Imperforate anus,

Question 18

What is the reason for an imperforated anus?

Answer 18

is due to a
failure of the cloacal diaphragm to involute.

Question 19

What causes stenosis?

Answer 19

Stenosis can also be caused by inflammatory
scarring, as may occur with:

• chronic gastroesophageal reflux,
• irradiation,
• scleroderma, or
• caustic injury.

Question 20

What are congenital duplication cysts?

Answer 20

Congenital duplication cysts are saccular or elongated cystic masses that *contain redundant
smooth muscle layers.*

These may be present in the esophagus, small intestine, or colon.