What is Mesenteric Adenitis?
Mesenteric adenitis is a condition where lymph nodes in the abdomen become swollen and inflamed, causing belly pain that can feel very similar to appendicitis, but it goes away on its own without surgery. 1, 2
Understanding the Basics
Think of lymph nodes as tiny filters throughout the body that help fight infections. In the abdomen, there's a curtain-like structure called the "mesentery" that holds the intestines in place, and it contains many of these lymph nodes. 2
- When these lymph nodes get irritated and swell up, it's called mesenteric adenitis 2
- This typically happens in children, teenagers, and young adults 2
- The condition is self-limiting, meaning it resolves completely on its own without any treatment beyond comfort measures 2
What Does It Feel Like?
The symptoms can be confusing because they mimic appendicitis:
- Pain in the right lower part of the belly (the same area where appendix pain occurs) 1, 3
- Fever (sometimes up to 104°F or 40°C) 4
- Sometimes diarrhea or vomiting 1, 4
- The pain typically lasts longer before families seek medical care (average 2-3 days) compared to appendicitis 1
How Common Is It?
Mesenteric adenitis is actually very common—it accounts for about 1 in 5 cases where children come to the emergency room with suspected appendicitis but turn out not to have it 3. This makes it one of the most frequent alternative diagnoses when appendicitis is suspected. 1
How Is It Diagnosed?
- Ultrasound is the main way doctors diagnose this condition 2, 3
- The ultrasound shows 3 or more swollen lymph nodes (each at least 8mm in size) in the belly, with a normal-looking appendix 2, 3
- Blood tests show less dramatic changes than appendicitis—white blood cell counts are lower and there's more of a specific type of white blood cell called lymphocytes 1
What Causes It?
The condition is usually triggered by a viral or bacterial infection, though often no specific germ is identified 2. In some cases, bacteria like Salmonella can be the cause. 4
How Long Does It Last?
This is important for families to understand:
- About half of children recover within 2 weeks 5
- The other half may have symptoms that come and go for 3 to 10 weeks 5
- Complete recovery always occurs without any lasting problems 2
What's the Treatment?
The treatment is supportive care only—meaning rest, staying hydrated, and pain medication like acetaminophen or ibuprofen 2. No antibiotics or surgery are needed in most cases. 2
Key Reassurance Points
- This is NOT appendicitis and does NOT require surgery 2
- Your child will recover completely with no long-term effects 2
- The swollen lymph nodes are simply the body's immune system responding to an infection 2
- Even though symptoms may persist for several weeks in some children, this doesn't mean anything is seriously wrong 5