What Causes Lymph Nodes in Your Stomach to Swell?

September 24, 2025 •

4 min read

According to the Mayo Clinic, a viral infection is the most common cause of inflamed abdominal lymph nodes. This condition, known as mesenteric lymphadenitis, can lead to painful swelling in the area and is often linked to an infection like gastroenteritis. Understanding what causes lymph nodes in your stomach to swell is key to identifying its symptoms.

Quick Summary

Swollen abdominal lymph nodes, or mesenteric lymphadenitis, are typically triggered by infections, most commonly viral gastroenteritis. The body's immune response to an intestinal infection causes the lymph nodes in the abdomen to enlarge as they work to filter out invaders.

Key Points

Mesenteric Lymphadenitis Explained: Swollen lymph nodes in the stomach area, or mesentery, is a condition known as mesenteric lymphadenitis, most common in children and teens.
Infection is the Main Culprit: The most frequent cause is a viral infection, such as gastroenteritis (stomach flu), but bacterial infections can also be responsible.
Distinguishing from Appendicitis: Symptoms can resemble appendicitis, but mesenteric lymphadenitis is often less severe and typically resolves without intervention as the infection clears.
Watch for Warning Signs: Seek medical advice if abdominal pain is severe, persistent, or accompanied by high fever or unexplained weight loss, as these can signal a more serious issue.
Diagnosis Through Imaging: Doctors commonly use CT scans or ultrasound to confirm the diagnosis and rule out other abdominal conditions.
Treatment Targets the Cause: Treatment focuses on addressing the underlying infection or inflammatory condition, with supportive care often sufficient for viral causes.

What is Mesenteric Lymphadenitis?

Lymph nodes are an integral part of the lymphatic system, which plays a crucial role in your body's immune defense. While most people are familiar with swollen lymph nodes in the neck or groin, they are also found in the mesentery, the thin tissue connecting the intestines to the abdominal wall. When these abdominal lymph nodes become inflamed, the condition is called mesenteric lymphadenitis.

This condition can mimic other serious abdominal issues, such as appendicitis or intussusception, especially in children and teenagers, who are most commonly affected. However, unlike these more severe conditions, mesenteric lymphadenitis often resolves on its own as the underlying cause clears up. The key is to understand the triggers and recognize when a doctor's visit is necessary.

The Common Causes of Swollen Abdominal Lymph Nodes

Viral and Bacterial Infections

By far, the most frequent reason for abdominal lymph node swelling is an infection. The lymph nodes act as filters, trapping germs and housing immune cells to fight them off. When an infection is present in or near the intestines, the nearby lymph nodes naturally react by swelling.

Viral Gastroenteritis: Often referred to as the 'stomach flu,' this is a leading cause. The viral infection causes inflammation throughout the intestines, leading to the swelling of the mesenteric lymph nodes as they work overtime to combat the virus.
Bacterial Infections: Certain bacteria can also cause the condition. One such example is Yersinia enterocolitica, a bacterium that can be found in undercooked pork and can lead to severe abdominal symptoms and inflammation of the lymph nodes.

Other Inflammatory Conditions

Infections are not the only culprits. Other diseases that cause inflammation can also lead to mesenteric lymphadenitis.

Inflammatory Bowel Disease (IBD): Conditions like Crohn's disease and ulcerative colitis, which cause chronic inflammation of the digestive tract, can result in swollen abdominal lymph nodes.
Appendicitis: Inflammation of the appendix can sometimes cause nearby mesenteric lymph nodes to swell. In some cases, the pain from mesenteric lymphadenitis can be confused with appendicitis, requiring careful diagnosis.
Diverticulitis: This condition, where small pouches in the colon become inflamed or infected, can also cause swelling in surrounding lymph nodes.

Less Common but Serious Conditions

While less frequent, certain serious health issues can also cause abdominal lymph node swelling.

Cancer: Cancers of the lymphatic system (lymphoma) or metastasis from other gastrointestinal cancers can cause lymph nodes to enlarge significantly. These nodes may feel harder and may not be tender.
Autoimmune Diseases: Systemic conditions like lupus or rheumatoid arthritis, which cause widespread inflammation, can lead to lymph node swelling throughout the body, including the abdomen.

When to See a Doctor

While most cases are mild and resolve on their own, it's important to know when to seek medical attention. Symptoms that should prompt a doctor's visit include:

Pain that is severe, persistent, or worsening.
High or prolonged fever.
Unexplained weight loss.
Loss of appetite or nausea.
Visible enlargement of lymph nodes in other areas, such as the neck or groin.
No improvement in symptoms within a few weeks.

Diagnostic and Treatment Approaches

Diagnosing mesenteric lymphadenitis typically starts with a physical exam and a review of your symptoms. A doctor will often use imaging tests to get a clearer picture of what's happening internally.

CT Scan: A computerized tomography (CT) scan is the most common and effective way to view enlarged abdominal lymph nodes and rule out other conditions.
Ultrasound: For children, an ultrasound may be used to see the lymph nodes without radiation exposure.
Blood Tests: These can help identify signs of infection or other inflammatory markers.

Treatment is directed at the underlying cause. If an infection is responsible, it will be treated with appropriate medication (e.g., antibiotics for bacterial infections). For viral cases, supportive care with rest, fluids, and over-the-counter pain relievers is often all that is needed. For more complex causes like IBD or cancer, a specialized treatment plan is required. For more information on inflammatory diseases, you can visit a reliable source like the National Institutes of Health.

Comparison of Common Causes


Feature	Viral Gastroenteritis	Bacterial Infection	Inflammatory Bowel Disease (IBD)	Lymphoma
Onset	Acute (often sudden)	Acute	Chronic or intermittent	Chronic
Symptoms	Abdominal pain, fever, diarrhea, vomiting	Abdominal pain, fever, severe diarrhea	Chronic diarrhea, pain, weight loss	Painless swelling, fever, weight loss
Associated Factors	Close contact with sick individuals	Contaminated food/water	Genetic and environmental factors	Unknown, can be associated with weakened immunity
Treatment	Supportive care (rest, fluids)	Antibiotics	Disease management with medication	Chemotherapy, radiation
Node Tenderness	Often tender	Often tender	Variable tenderness	Typically non-tender, firm

Conclusion

Understanding what causes lymph nodes in your stomach to swell is the first step toward finding relief. While an infection is the most common reason and often resolves on its own, it is important to be aware of the signs that may indicate a more serious condition. Always consult a healthcare professional for an accurate diagnosis, especially if symptoms are severe or persistent. Prompt medical evaluation ensures the correct treatment, ruling out conditions with similar symptoms and providing peace of mind.

Frequently Asked Questions

You can't feel these lymph nodes yourself, as they are located deep in the abdomen. The primary symptom is abdominal pain, which can be accompanied by fever, nausea, or diarrhea. A doctor can diagnose the condition using imaging tests like a CT scan.

Most cases of mesenteric lymphadenitis are not serious and are caused by a common viral infection that clears up on its own. However, persistent or severe swelling can indicate a more serious underlying condition, such as inflammatory bowel disease or, in rare cases, cancer, and should be evaluated by a doctor.

Stress does not directly cause lymph nodes to swell. While prolonged emotional stress can impact your immune system and potentially increase susceptibility to infections, the swelling itself is caused by the body's immune response to an infection or inflammation.

The fastest way to treat swollen lymph nodes is to address the underlying cause. For simple infections, rest, fluids, and over-the-counter pain relievers can help manage symptoms while the body fights the infection. There is no instant fix; the swelling will reduce as the infection clears.

Yes, it is possible to have mesenteric lymphadenitis without a fever. While fever is a common symptom, the absence of one does not rule out the condition. The main symptom is abdominal pain, which can vary in intensity.

Mesenteric lymphadenitis involves swelling of multiple lymph nodes in the mesentery, while appendicitis is inflammation of the appendix. Mesenteric lymphadenitis pain is often more widespread, whereas appendicitis pain is typically localized to the lower right abdomen and is usually more severe and constant. A CT scan is often used to differentiate between the two.

Yes, food poisoning, which is often caused by bacterial infections like Yersinia enterocolitica, can certainly cause mesenteric lymphadenitis. The infection in the gastrointestinal tract triggers the immune response that leads to swollen abdominal lymph nodes.