Mesenteric adenitis or mesenteric lymphadenitis is inflammation of the mesenteric lymph nodes in the RIF. It is important as it is a commonly misdiagnosed as acute appendicitis. It is also most common in children and adolescents (just like acute appendicitis).
Pathophysiology
Bacteria and viruses access intestinal lymphatics and multiply in the mesenteric lymph nodes leading to enlarged yet soft lymph nodes. There may be necrosis and pus of these lymph nodes.
It may also present with ileocolitis which may mean that it is secondary to a primary pathogen.
Causative agents
- EBV + other viruses (maybe even Covid-19)
- Yersinia enterocolitica - most common in Europe, NA, and Australia.
- Helicobacter jejuni
- Campylobacter jejuni
- Salmonella spp.
- Shigella spp.
- Mycobacterium tuberculosis
😷 Presentation
⭐️ RIF pain similar to acute appendicitis.
🔍 Investigations
Imaging
CT or USS may identify enlarged lymph nodes in the RIF region. We may also see ileal thickening and we should also see a normal appendix.
🧰 Management
It is typically self-limiting.