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idiopathic eosinophilic colitis

Friday 3 October 2003

primary eosinophilic colitis

Definition: Idiopathic eosinophilic colitis is a rare inflammatory disease characterized by eosinophilic infiltration of the colon and peripheral blood eosinophilia.

Eosinophilic or allergic colitis has been described as a common entity, but its exact prevalence is unknown.

Walker-Smith, one of the pioneers in the study of gastrointestinal food allergy, stated that, since the last decade CMA has been occurring with different manifestations when compared to those observed in the 1970s and 1980s, when there was a predominance of enteropathy induced by the milk in the infants’ diet with infections by enteropathogenic Escherichia coli.

In this context, the epidemiological study performed in Brazil demonstrated that 20.6% of infants with known or suspected CMA had blood in the stool that might be the result of allergic or eosinophilic colitis.

Eosinophilic colitis is considered one of the presentations of primary gastrointestinal eosinophilic diseases. This group of diseases also includes:
- eosinophilic esophagitis,
- eosinophilic gastritis,
- eosinophilic gastroenteropathy.

The differential diagnosis of eosinophilic diseases must include causes that may result in secondary eosinophilic infiltration, such as certain intestinal parasites (Enterobius vermicularis, Strongyloides stercoralis, and Trichuris trichiura) and drugs (carbamazepine, rifampicin, gold, non-steroidal anti-inflammatory drugs, and tacrolimus).

It is also noteworthy that the clinical picture depends on the predominance of eosinophilic infiltration in the different layers of the intestine, that is, mucosal, muscularis, and serosa layers. There is a high association with atopy at all ages; however, in infants, the connection with food allergy is more frequently established.

Conversely, in adults, in addition to the adverse reaction to foods, other mechanisms lead the treatment to often include medicines in addition to elimination diet. Thus, the term "allergic colitis" can be used as a second alternative to denominate "eosinophilic colitis", in a more appropriate form for infants.


- In patients who underwent colonoscopy or rectosigmoidoscopy, areas of friability and erosive lesions of the mucosa have been shown.
- eosinophil infiltration (between 5 and 25 per high-power field) in 89.3% of patients. - foci of erythema,
- chronic inflammatory infiltrate with areas of activity (lymphocytes, plasma cells, eosinophils),
- signs of degeneration and regeneration of epithelial cells.

Open References

- Eosinophilic colitis in infants. Lozinsky AC, Morais MB. J Pediatr (Rio J). 2014 Jan-Feb;90(1):16-21. doi : 10.1016/j.jped.2013.03.024 PMID: 24131740 [Free]

- Diagnosing eosinophilic colitis: histopathological pattern or nosological entity?
Bates AW. Scientifica (Cairo). 2012;2012:682576. doi : 10.6064/2012/682576 PMID: 24278727 [Free]

Paywall references

- Primary Colonic Eosinophilia and Eosinophilic Colitis in Adults. Turner KO, Sinkre RA, Neumann WL, Genta RM. Am J Surg Pathol. 2016 Oct 27. PMID: 27792062