Mesenteric Adenitis

Mesenteric adenitis is a difficult diagnosis to make, but it is always a diagnosis of exclusion. There isn't much FOAMEd that I can find on mesenteric adenitis, and the trusty sunflower book doesn't actually say a lot about it. It lumps mesenteric adenitis with non-specific abdominal pain, and says NSAP is less severe than appendicitis, often accompanied by an URTI with cervical lymphadenopathy.

Pathophysiology
- Self-limiting illness
- Often affects the lymph nodes in the right lower quadrant only

- Pathogens are thought multiply in mesenteric lymph nodes. On gross pathology, lymph nodes are enlarged and soft. On microscopy, there is non-specific hyperplasia and when suppurative, there is necrosis and pus.

Mesenteric adenitis has a number of causes:
    variety of viruses
    Yersinia enterocolitica (Europe, North America and Australia)
    Helicobacter jejuni
    Campylobacter jejuni
    Salmonella spp
    Shigella spp

Treatment and prognosis
Self-limiting, and typically abates over the course of a few weeks.

Interestingly, when mesenteric adenitis (or appendicitis) occurs in childhood or adolescence, there is a significantly reduced risk of ulcerative colitis later in life.

Differential diagnosis
The clinical differential includes:
    acute appendicitis
        lymph nodes are generally smaller and fewer
        appendix is abnormal
    intussusception
    Meckel's diverticulitis

http://radiopaedia.org/articles/mesenteric-adenitis

Any #FOAMPed pearls or tips on mesenteric adenitis vs appendicitis? There's an apparent dearth of relevant FOAMEd! http://t.co/Skl5MUoM4U
— Charlotte Davies (@OneLongPlait) March 29, 2014