JIA: Jejunoileal Atresia

Def: an obstruction of the middle region (jejunum) or distal region (ileum) of the small intestine.

The small intestine immediately proximal to the obstruction become enlarged or dialated. Impairing ability to absorb nutrients Impairing peristaltic movement of the small bowel

1) Definition of JIA and anatomic site that it occurs, noting subtypes of this malformation if applicable

JIA Type I: Mesenteric development and intestinal length are normal Mucosa and submucosa forms a web or

membrane within the intestinal lumen Windsock Effect

Increased pressure proximal to the obstruction causes the web to prolapse, pushing the web through the bowel distally

1) Definition of JIA and anatomic site that it occurs, noting subtypes of this malformation if applicable

JIA Type II: Mesenteric development and overall intestinal length is normal Small bowel is not a continuous lumen Proximal small bowel ends in bulbous blind pouch Distal small bowel is flattened Proximal and distal small bowel connected by

fibrous cord.

1) Definition of JIA and anatomic site that it occurs, noting subtypes of this malformation if applicable

Type IIIa: Similar to Type II Small V-shaped mesenteric defect is present, bowel length is shortened Proximal blind end is markedly dilated and

aperistaltic No fibrous cord connects the proximal and distal

small bowel

1) Definition of JIA and anatomic site that it occurs, noting subtypes of this malformation if applicable

Type IIIb: Similar to Type IIIa Significant mesenteric defect is present

Superior mesenteric artery is largely absent Small bowel supplied by a single ileocolic or right colic

artery Known as Christmas tree or apple peel deformity

Bowel wraps around a single perfusing artery

1) Definition of JIA and anatomic site that it occurs, noting subtypes of this malformation if applicable

Type IV: Multiple JIAs of any combination Types I – III

Appears as a string of sausages due to multiple lesions

Likely result of multiple ischemic insults or inflammatory process

1) Definition of JIA and anatomic site that it occurs, noting subtypes of this malformation if applicable

1) Definition of JIA and anatomic site that it occurs, noting subtypes of this malformation if applicable

Intrauterine vascular accident Necrosis of bowel segment Resorption of tissue IVAs caused by malrotation, volvulus (abnormal

twisting of SMA), gastroschisis, omphalocele All result in blood supply / gut segment separation

Duodenal Atresia is usually a failure to recanalize versus vascular insult of JIA

2) Embryologic cause of this malformation; how does the mechanism differ from duodenal atresia? When does this malformation occur?

Within the first day of life Vomiting green bile Bowel sounds absent in distal small intestine No meconium Abdominal distention

3) Describe the typical clinical patient presentation in JIA: symptoms, onset, age, physical exam findings.

Prenatally Ultrasonography will likely show excess amniotic fluid

(polyhydromnios) Intestines aren’t properly absorbing ingested amniotic fluid

First day of life Abdominal X-ray, with and w/o contrast enema

Stomach and proximal small bowel will appear dilated Distal small bowel will appear flattened

4) Describe the recommended method for diagnosing suspected JIA

5) Typical X-Ray findings in JIA

5) Typical X-Ray findings in JIA

Triple Bubble Presentation

Immediately a tube is placed orally into the stomach to evacuate excess fluid and gasses Prevents vomiting and aspiration Relieves GI discomfort

IV Fluids and Nutrients are provided until surgery is available

Surgical intervention is necessary to repair the bowel obstruction and blood supply

6) Initial stabilizing treatment versus definitive surgical treatment and prognosis in JIA.

After surgery, patients will have a feeding tube until bowel movements begin

Typical hospital stay post-surgery is a few weeks or until patient is nutritionally stable

Regular follow-up is required to check bowel development and function

6) Initial stabilizing treatment versus definitive surgical treatment and prognosis in JIA.

Types I, II, and IIIa have good prognosis Fairly normal small bowel length results in almost

normal bowel function

Types IIIb, IV is associated with complications Shortened small bowel is associated with short

gut syndrome and malabsorption

6) Initial stabilizing treatment versus definitive surgical treatment and prognosis in JIA.

References Sadler, TW. Langman’s Medical Embryology, 8th ed. 2000.

Intestinal Atresia, Stenosis, and Webs. May 1, 2006. http://www.emedicine.com/ped/topic3043.htm. Accessed Nov. 26, 2007.

Bowel Obstruction in the Newborn. June 15, 2004. http://www.emedicine.com/ped/topic2857.htm. Accessed Nov. 26, 2007.

Intestinal Atresia and Stenosis in Children. Nov. 27, 2007. http://www.chp.edu/centers/03x_lit_disease_15.php. Accessed Nov. 27, 2007

Intestinal Atresia – University of Michigan Pediatric Surgery. Apr. 23, 2007. http://surgery.med.umich.edu/pediatric/clinical/physician_content/a-m/intestinal_atresia.shtml. Accessed Nov. 26, 2007.

Intestinal Atresia and Stenosis, Cincinnati Children’s Hospital Medical Center. Apr. 2007. http://www.cincinnatichildrens.org/health/info/abdomen/diagnose/obstructions.htm. Accessed Nov 26, 2007.