7 Critical Intussusception Symptoms You Should Never Ignore

Intussusception is a serious medical condition that occurs when one segment of the intestine telescopes or slides into an adjacent section, much like a collapsible telescope. This condition creates a blockage that prevents food and fluids from passing through, while also cutting off blood supply to the affected portion of the intestine. While intussusception can occur at any age, it is most common in infants and young children between 6 months and 3 years old. Recognizing the symptoms early is crucial, as prompt medical intervention can prevent serious complications including tissue death, perforation, and life-threatening infections.

Understanding the warning signs of intussusception can be lifesaving. This condition typically develops suddenly and requires immediate medical attention. Parents, caregivers, and adults should be aware of the characteristic symptoms that distinguish this emergency from common stomach issues. The following symptoms are the most important indicators of intussusception that should never be ignored.

1. Severe Intermittent Abdominal Pain

The hallmark symptom of intussusception is sudden, severe abdominal pain that comes and goes in waves. These episodes typically occur every 15 to 20 minutes and last for a few minutes each time.

In infants and young children: The pain manifests as sudden, intense crying episodes where the child may pull their knees up to their chest. Between these painful episodes, the child may appear relatively normal or lethargic. This cyclical pattern of distress followed by calm periods is highly characteristic of intussusception.

In older children and adults: The pain is described as cramping and colicky in nature, often starting suddenly and becoming progressively worse. The intermittent pattern may be less obvious in adults, but the severity and location of pain in the abdomen remain distinctive features.

The pain occurs because the telescoped intestine segment causes temporary blockage and stretching of the bowel wall. As the intestinal muscles contract in waves (peristalsis), they attempt to push contents through the blocked area, creating intense cramping sensations.

2. Currant Jelly Stools (Bloody, Mucoid Stools)

One of the most distinctive and alarming symptoms of intussusception is the passage of stools that resemble currant jelly—dark red or maroon in color with a mucus-like consistency. This symptom typically appears as the condition progresses.

The characteristic appearance occurs because:

• The blocked intestine becomes congested and inflamed
• Blood vessels in the intestinal wall are compressed, causing bleeding
• The intestinal lining produces excess mucus in response to the irritation
• Blood and mucus mix together, creating the jelly-like appearance

While this symptom is highly specific to intussusception, it may not appear immediately. In fact, currant jelly stools often develop several hours after the onset of other symptoms. The absence of this sign does not rule out intussusception, especially in the early stages. However, when present, it should prompt immediate emergency medical evaluation as it indicates that blood supply to the intestine is compromised.

3. Vomiting

Vomiting is a common and early symptom of intussusception that occurs in the majority of cases. The vomiting associated with this condition has specific characteristics that help distinguish it from simple gastroenteritis or other stomach bugs.

Progression pattern: Initially, the vomiting may bring up stomach contents and food. As the condition progresses and the intestinal obstruction worsens, the vomit may become bilious (greenish-yellow in color due to bile). In severe cases, if the blockage is complete and prolonged, the vomit may eventually have a fecal odor, indicating that intestinal contents are backing up significantly.

Frequency and timing: Vomiting episodes often coincide with or follow the waves of abdominal pain. The child or adult may vomit repeatedly, leading to dehydration if not addressed promptly.

The vomiting occurs because the telescoped intestine creates a blockage that prevents normal passage of digestive contents. The body attempts to expel the backed-up material through vomiting. This symptom, combined with decreased fluid intake due to pain and nausea, can quickly lead to dehydration, especially in young children.

4. Abdominal Distension and Swelling

As intussusception progresses, the abdomen may become visibly swollen, distended, or bloated. This physical change occurs due to the accumulation of gas, fluids, and intestinal contents above the point of obstruction.

Physical characteristics:

• The abdomen appears larger than normal and may feel tight or tense when touched
• The swelling is usually generalized across the entire abdomen
• The distended abdomen may be tender to touch, causing increased discomfort
• In some cases, a sausage-shaped mass may be felt in the abdomen, representing the telescoped intestine segment

Healthcare providers examining patients with suspected intussusception often palpate (feel) the abdomen carefully. In approximately 60-85% of cases, they can detect an elongated, sausage-shaped mass, typically in the right upper abdomen or the middle of the abdomen. This mass represents the intussuscepted bowel segment itself.

The distension develops because the obstruction prevents gas and digestive contents from moving through the intestinal tract normally. As material accumulates proximal to (before) the blockage, the affected bowel segments stretch and expand, creating visible swelling.

5. Lethargy and Weakness

Children with intussusception often exhibit unusual sleepiness, extreme tiredness, or decreased responsiveness that is disproportionate to what would be expected from a simple stomach illness. This lethargy is a concerning sign that should not be dismissed.

Why lethargy occurs:

• Pain exhaustion: The repeated episodes of intense pain are physically and emotionally exhausting, particularly for infants and young children
• Dehydration: Vomiting and decreased fluid intake quickly lead to dehydration, causing weakness and drowsiness
• Compromised blood flow: When blood supply to the intestine is reduced, the body may respond with systemic symptoms including lethargy
• Developing shock: In severe cases, lethargy may indicate early shock due to fluid loss, pain, and compromised intestinal blood flow

Important distinction: While it’s normal for sick children to be somewhat tired, the lethargy associated with intussusception is often more profound. The child may be difficult to rouse, uninterested in their surroundings, or may alternate between extreme irritability during pain episodes and abnormal sleepiness between episodes.

In adults, this symptom manifests as profound fatigue, weakness, and a general feeling of being unwell that seems excessive for abdominal pain alone. This systemic response indicates that the body is under significant stress.

6. Loss of Appetite and Refusal to Eat

A sudden loss of interest in food or refusal to eat is a common symptom of intussusception, particularly noticeable in children who normally have good appetites.

In infants: Babies may refuse the breast or bottle, turn their head away from feeding, or may start feeding but then stop abruptly and cry. Some infants may be able to feed during the pain-free intervals but refuse food when experiencing abdominal cramping.

In children and adults: There is typically a complete loss of appetite with no interest in favorite foods. The thought of eating may increase nausea, and attempts to eat may trigger vomiting.

This symptom occurs for several reasons:

• The intestinal obstruction creates a sensation of fullness
• Nausea accompanies the abdominal pain
• The body instinctively avoids adding more material to an already blocked digestive system
• Pain and discomfort override hunger signals

While many illnesses can cause temporary loss of appetite, the combination of food refusal with other symptoms like intermittent severe pain and vomiting should raise concern for a more serious condition like intussusception.

7. Fever and Signs of Infection

Although not always present in the early stages, fever can develop as intussusception progresses, particularly if complications are beginning to occur.

Fever characteristics:

• May be low-grade initially but can become higher as the condition worsens
• Often develops several hours after the onset of other symptoms
• Presence of fever may indicate inflammation, ischemia (reduced blood flow), or early infection

Why fever develops: When the intestine is telescoped, blood supply to that section becomes compromised. Without adequate blood flow, the intestinal tissue becomes ischemic and may begin to die (necrosis). This tissue damage triggers an inflammatory response, and the body may develop fever as part of its immune reaction. If the intestinal wall becomes severely damaged or perforated, bacteria from the intestine can leak into the abdominal cavity, leading to peritonitis (infection of the abdominal lining) and sepsis.

Associated signs of serious complications:

• Rapid heart rate (tachycardia)
• Rapid breathing
• Increasing abdominal pain that becomes constant rather than intermittent
• Abdominal rigidity (the belly becomes very hard)
• Worsening lethargy or confusion

The development of fever in combination with other intussusception symptoms is particularly concerning and indicates that the condition may be advancing to a more dangerous stage requiring urgent surgical intervention.

Common Causes of Intussusception

Understanding what causes intussusception can help identify individuals who may be at higher risk. The causes differ somewhat between children and adults.

Causes in Infants and Young Children:

Idiopathic (Unknown Cause): In approximately 90% of cases in children, no specific cause is identified. The intussusception occurs spontaneously, possibly related to:

• Viral infections that cause swelling of lymphoid tissue in the intestinal wall (Peyer’s patches)
• Recent upper respiratory infection or gastroenteritis
• Normal variations in intestinal motility during development

Lead Points (Identifiable Triggers): In about 10% of pediatric cases, a specific anatomical abnormality serves as a “lead point” that triggers the telescoping:

• Meckel’s diverticulum: A congenital pouch in the small intestine
• Intestinal polyps: Growths in the intestinal lining
• Enlarged lymph nodes: Swollen lymphoid tissue due to infection
• Henoch-Schönlein purpura: An inflammatory condition affecting blood vessels
• Intestinal duplication: Congenital abnormalities where parts of the intestine are duplicated

Causes in Adults:

Intussusception in adults is rare and almost always has an identifiable structural cause (up to 90% of cases):

• Benign tumors: Lipomas, adenomas, or polyps in the intestinal wall
• Malignant tumors: Colorectal cancer or lymphoma
• Inflammatory bowel disease: Crohn’s disease or ulcerative colitis
• Post-surgical adhesions: Scar tissue from previous abdominal surgeries
• Celiac disease: In rare cases, chronic inflammation may contribute

Other Risk Factors:

• Age: Peak incidence is between 6 months and 3 years old
• Gender: Boys are affected slightly more often than girls (approximately 3:2 ratio)
• Previous intussusception: Children who have had one episode have a small risk of recurrence (5-10%)
• Cystic fibrosis: Children with this condition have a higher risk

Prevention of Intussusception

Because most cases of intussusception in children occur spontaneously without a clearly identifiable cause, prevention is generally not possible. However, there are some considerations regarding risk reduction and early detection:

Vaccination Considerations:

The rotavirus vaccine has been associated with a very small increased risk of intussusception, primarily in the first week after the first or second dose. However:

• The risk is extremely small (approximately 1-5 cases per 100,000 vaccinated infants)
• This small risk is far outweighed by the vaccine’s benefits in preventing severe rotavirus gastroenteritis
• Medical authorities including the CDC, WHO, and AAP continue to recommend rotavirus vaccination
• Parents should be aware of intussusception symptoms, especially in the week following vaccination

Early Recognition and Prompt Treatment:

While prevention may not be possible, the best approach to reducing complications is:

• Awareness: Parents, caregivers, and healthcare providers should be familiar with the classic symptoms
• Prompt medical evaluation: Any infant or child with severe intermittent abdominal pain, vomiting, and lethargy should receive immediate medical assessment
• Don’t delay: Early diagnosis and treatment significantly improve outcomes and reduce the need for surgical intervention

For Adults:

• Regular screening: Age-appropriate colorectal cancer screening can detect polyps and tumors before they cause intussusception
• Management of intestinal conditions: Proper treatment and monitoring of inflammatory bowel disease and other intestinal disorders
• Prompt evaluation of symptoms: Adults experiencing unexplained abdominal pain and other gastrointestinal symptoms should seek medical evaluation

Monitoring After Treatment:

For children who have experienced intussusception:

• Parents should be educated about recurrence risk and warning signs
• Follow-up care as recommended by healthcare providers
• Prompt attention to any recurring symptoms, particularly in the weeks to months following treatment

Frequently Asked Questions

How quickly do intussusception symptoms develop?

Symptoms typically develop suddenly and progress rapidly. The characteristic intermittent abdominal pain usually begins abruptly, and other symptoms like vomiting often appear within the first few hours. The condition requires prompt medical attention, ideally within 24 hours of symptom onset, to prevent serious complications.

Can intussusception resolve on its own?

In rare cases, particularly in young infants, intussusception may spontaneously reduce (resolve on its own). However, this cannot be relied upon, and the condition should always be treated as a medical emergency. Waiting for spontaneous resolution risks serious complications including intestinal perforation, tissue death, and life-threatening infection.

Is intussusception always painful?

Yes, pain is almost always present and is typically severe. The intermittent, colicky nature of the pain—coming in waves—is one of the most characteristic features. In infants who cannot verbalize pain, inconsolable crying, drawing up of the legs, and extreme fussiness indicate severe discomfort.

What is the difference between intussusception and a stomach virus?

While both conditions can cause vomiting and abdominal discomfort, intussusception has several distinguishing features: severe intermittent pain that comes in regular waves, currant jelly stools (not typically seen with viral gastroenteritis), a palpable abdominal mass, and more profound lethargy. Stomach viruses usually cause more constant, milder discomfort along with diarrhea, and symptoms gradually improve. If there’s any doubt, medical evaluation is essential.

At what age is intussusception most common?

Intussusception most commonly affects infants and children between 6 months and 3 years of age, with the peak incidence around 9-12 months. However, it can occur at any age, including in older children and adults, though this is less common.

How is intussusception diagnosed?

Diagnosis typically involves a combination of physical examination, medical history, and imaging studies. Ultrasound is often the first imaging test used, as it can show the characteristic “target sign” or “doughnut sign” of telescoped intestine. Other imaging methods may include X-rays or CT scans. In some cases, an air or contrast enema is used for both diagnosis and treatment.

Can intussusception happen more than once?

Yes, recurrence is possible but relatively uncommon, occurring in approximately 5-10% of cases after successful treatment with enema reduction. Recurrence is more likely if there’s an underlying structural abnormality. Children who have had intussusception once should be monitored carefully, and parents should be especially vigilant for returning symptoms.

Should I go to the emergency room if I suspect intussusception?

Yes, absolutely. Intussusception is a medical emergency that requires immediate evaluation and treatment. If you notice symptoms such as severe intermittent abdominal pain (especially with leg drawing in infants), vomiting, bloody stools, or unusual lethargy, seek emergency medical care immediately. Early treatment significantly improves outcomes and may avoid the need for surgery.

Is surgery always necessary for intussusception?

Not always. In many cases, especially when diagnosed early, intussusception can be successfully treated with a non-surgical procedure called pneumatic or hydrostatic reduction (using air or fluid enema to push the telescoped intestine back into place). However, surgery becomes necessary if: the enema reduction is unsuccessful, there are signs of intestinal perforation or dead tissue, the condition has been present for an extended period, or there’s an underlying structural abnormality that needs correction.

What complications can occur if intussusception is not treated promptly?

Delayed treatment can lead to serious complications including intestinal perforation (a hole in the intestinal wall), peritonitis (abdominal infection), sepsis (body-wide infection), intestinal necrosis (tissue death), and in severe cases, death. The compromised blood supply to the telescoped intestine segment means that tissue damage can occur within hours, making prompt medical intervention critical.

References:

• Mayo Clinic – Intussusception
• National Center for Biotechnology Information – Intussusception
• Johns Hopkins Medicine – Intussusception
• Boston Children’s Hospital – Intussusception
• Centers for Disease Control and Prevention – Rotavirus