Jejunal Atresia: Symptoms, Types, Causes and Treatment

Jejunal atresia is a congenital condition that results in blockage or absence of a portion of the jejunum, the middle segment of the small intestine. This condition is a leading cause of intestinal obstruction in newborns, and while advances in surgical care have significantly improved outcomes, the disease remains a critical challenge for pediatric surgeons and neonatologists. Understanding its symptoms, types, causes, and treatments is vital for healthcare professionals and families alike.

Symptoms of Jejunal Atresia

Jejunal atresia typically presents within the first days of life, often as a neonatal emergency. Early recognition of symptoms is crucial for timely intervention and improved prognosis.

Symptom	Onset	Key Features	Source(s)
Bilious vomiting	First days	Greenish vomit, often after feeds	7
Abdominal distension	Early	Swollen, firm abdomen	7
Failure to pass meconium	First 24 hours	No first stool, indicates obstruction	7
Feeding intolerance	Early	Refusal to feed, regurgitation	8

Table 1: Key Symptoms

Bilious Vomiting

One of the most classic and immediate symptoms of jejunal atresia is bilious vomiting. This occurs because the blockage prevents intestinal contents from passing, leading to a buildup that is regurgitated. The vomit is characteristically green due to the presence of bile, a marker that the obstruction is below the level of the stomach and duodenum 7.

Abdominal Distension

As the intestinal contents cannot move past the atretic segment, the abdomen becomes distended. This swelling is often visible and palpable, and it may worsen over time if not managed promptly 7.

Failure to Pass Meconium

Meconium is the first stool produced by newborns, typically passed within the first 24 hours. In jejunal atresia, the obstruction prevents this, so infants often fail to pass meconium or might pass only a small amount 7. This is a significant warning sign that warrants further investigation.

Feeding Intolerance

Infants with jejunal atresia may refuse to feed or vomit soon after feeding. They may become irritable, show little interest in eating, or have difficulty maintaining normal feeding patterns 8.

Types of Jejunal Atresia

Jejunal atresia is not a single disease but a group of related anatomic defects. Classifying these types helps guide treatment and predict outcomes.

Type	Anatomic Features	Clinical Impact	Source(s)
Type I	Mucosal web, intact bowel wall	Mildest, easiest to repair	1 7
Type II	Blind ends connected by fibrous cord	Moderate, isolated defect	1 7
Type IIIa	Complete separation, V-shaped mesenteric gap	More severe, potential for short bowel	1 7
Type IIIb ("Apple-peel")	Proximal atresia, distal bowel spirals around artery	High risk, short bowel syndrome	3 5
Type IV	Multiple atresias (string of sausages)	Most severe, high risk for malabsorption	1 7

Table 2: Major Types of Jejunal Atresia

Classic Classification and Morphology

Type I

• Description: The bowel is continuous but occluded by a mucosal web.
• Implications: Typically the least severe; resection or incision of the web restores continuity. Outcomes are generally excellent 1 7.

Type II

• Description: The two blind ends of the bowel are connected by a fibrous cord, but the mesentery is intact.
• Implications: Surgical correction involves resection and primary anastomosis, with favorable prognosis 1 7.

Type IIIa

• Description: Complete separation of the bowel with a defect in the mesentery, forming a V-shaped gap.
• Implications: More bowel loss and a higher risk of short bowel syndrome 1 7.

Type IIIb ("Apple-Peel" or "Christmas Tree" Atresia)

• Description: Proximal jejunal atresia with a large portion of the small intestine (usually ileum) coiled around a single artery, resembling an "apple peel" or "Christmas tree" 3 5.
• Implications: Associated with significant loss of bowel length and high risk for short bowel syndrome and nutritional complications 3 5.

Type IV

• Description: Multiple atresias along the small intestine, resembling a "string of sausages."
• Implications: Most severe form, often resulting in extensive bowel resection and lifelong nutritional challenges 1 7.

Complex and Variant Types

Recent literature describes further variants, such as Type IIIC, which involves unique anatomical arrangements but may have better outcomes with careful management 5. Complex atresias, including those associated with volvulus, colonic atresia, or distal "apple peel" appearances, are more challenging and may require advanced surgical techniques and multidisciplinary care 4.

Causes of Jejunal Atresia

Understanding why jejunal atresia occurs helps clinicians anticipate associated anomalies and counsel families.

Cause/Mechanism	Description	Typical Result	Source(s)
Intrauterine vascular accident	Disruption of blood flow during fetal life	Bowel necrosis & atresia	2 6 7 9 11
Intrauterine intussusception	Bowel telescopes into itself in utero	Segmental loss, atresia	6 8 9
Volvulus in utero	Twisting of intestine disrupts blood flow	Segmental necrosis, atresia	6 10
Genetic predisposition	Rare/familial cases documented	May have recurrence	1

Table 3: Causes and Mechanisms

Vascular Disruption: The Leading Theory

The most widely accepted explanation for jejunal atresia is a vascular accident during fetal life. This event interrupts the blood supply to a segment of the developing intestine, causing tissue death and subsequent atresia. Experimental models have replicated this by ligating mesenteric vessels in animal fetuses, producing atresia identical to that seen in humans 2 7 11. Apple-peel or "Christmas tree" atresia is particularly associated with a large mesenteric defect, resulting from a more extensive vascular injury 3 5.

Intussusception and Volvulus

Occasionally, the bowel may telescope into itself (intussusception) or twist (volvulus) during fetal development. These events also compromise blood flow and can lead to segmental atresia 6 8 9. While intrauterine intussusception is rare, it is a documented mechanism, especially in certain types of atresia 6 9.

Other Contributing Factors

• Cystic lymphangioma: Rarely, local masses such as cystic lymphangioma may compress mesenteric vessels, causing atresia 10.
• Genetic factors: Although most cases are sporadic, familial clustering suggests a possible genetic susceptibility in rare instances 1.

Treatment of Jejunal Atresia

Treatment of jejunal atresia is a surgical emergency but has evolved significantly, leading to excellent survival rates in most cases.

Intervention	Approach/Technique	Special Considerations	Source(s)
Resection & primary anastomosis	Remove atretic segment, join ends	Most common, high success	7 11 15
Tapering or plication of dilated bowel	Reduce size of dilated proximal segment	Prevents functional obstruction	12 14
Bowel-lengthening procedures	For short bowel syndrome	Needed in complex/multiple atresias	4
Parenteral nutrition	IV nutrition post-op or for short bowel	Essential for recovery, growth	3 4 15
Multidisciplinary management	Neonatology, nutrition, surgery	For complex or high-risk cases	4 15

Table 4: Treatment Options

Surgical Management

Resection and Primary Anastomosis

The standard treatment is resection of the atretic segment(s) and primary end-to-end anastomosis of healthy bowel ends. This approach restores bowel continuity and is associated with high survival rates when performed promptly and expertly 7 11 15.

Tapering, Plication, and Jejunoplasty

In cases where the proximal bowel is excessively dilated, tapering or plication (folding and suturing) may be performed to reduce the diameter and improve function 12 14. These procedures help prevent postoperative functional obstruction and preserve bowel length, which is especially important in patients at risk for short bowel syndrome.

Complex and Multiple Atresias

When multiple atresias or extensive bowel loss occurs (Type IV, apple-peel), more advanced techniques such as bowel-lengthening procedures may be necessary. These are often performed in specialized centers and require multidisciplinary expertise 4.

Nutritional Support and Postoperative Care

Parenteral Nutrition

Total parenteral nutrition (TPN), administered via intravenous infusion, is often required postoperatively—especially in cases of short bowel syndrome or when enteral feeding is not immediately possible. Advances in TPN have greatly improved the outlook for affected infants, enabling normal growth and development despite significant bowel loss 3 4 15.

Multidisciplinary Approach

Complex cases benefit from a team that includes pediatric surgeons, neonatologists, gastroenterologists, and nutritionists. Early diagnosis, prompt surgical intervention, and expert nutritional support are key factors in improved survival and outcomes 4 15.

Management of Complications

• Adhesive intestinal obstruction: Sometimes occurs post-surgery, requiring careful monitoring or further intervention 4.
• Short bowel syndrome: Managed with specialized nutritional support and, in select cases, bowel-lengthening surgery 3 4 15.
• Sepsis and infection control: Critical in the early post-operative period 7.

Conclusion

Jejunal atresia remains a significant neonatal surgical emergency, but contemporary advances in surgical and nutritional management have transformed outcomes. Early recognition and a systematic, multidisciplinary approach are essential in optimizing survival and long-term health.

Key Points:

• Early symptoms include bilious vomiting, abdominal distension, failure to pass meconium, and feeding intolerance.
• Classifications of jejunal atresia (Types I-IV and variants) guide prognosis and surgical planning.
• Primary causes involve intrauterine vascular accidents, with rare contributions from intussusception, volvulus, or local compressive lesions.
• Treatment centers on surgical correction, supported by advanced nutritional care, and is often highly successful in specialized settings.
• Complex cases require individualized, multidisciplinary management to address challenges like short bowel syndrome and postoperative complications.

Awareness and early intervention remain the cornerstones of successful management for infants born with this challenging yet increasingly treatable condition.