[Sprue-like enteropathy due to olmesartan: a case report]

Immunopathogenesis of olmesartan-associated enteropathy

BACKGROUND

Olmesartan-associated enteropathy (OAE) is characterised by diarrhoea, nausea, vomiting, abdominal pain, weight loss and severe sprue-like enteropathy, all of which are resolved after discontinuation of olmesartan medoximil.

AIM

To determine the mechanistic similarities of OAE with coeliac sprue.

METHODS

Duodenal biopsies were extracted from OAE patients before (n = 11) or after (n = 17) discontinuation of olmesartan medoxomil (on or off olmesartan medoxomil). There were seven 'on/off' paired samples. Formalin-fixed biopsies were stained for CD8, CD4, FoxP3, IL-15R and psmad 2/3. Caco2 cells (human colonic epithelial line) were treated with olmesartan medoxomil and stained for IL-15, IL-15R and ZO-1.

RESULTS

In the 'on olmesartan medoxomil' duodenal biopsies, a significant increase in the numbers of CD8+ cells and the number of cells that are FoxP3+ (a regulatory T-cell marker) are present in the duodenum as compared to the duodenal biopsies from patients who discontinued olmesartan medoxomil. IL15R expression is also increased with olmesartan medoxomil use. Evaluation of the effect of olmesartan medoxomil upon Caco-2 cells demonstrated that IL15 expression is increased in response to olmesartan medoxomil treatment. Further, ZO-1, a tight junction protein, is disrupted in olmesartan medoxomil-treated Caco-2 cells.

CONCLUSIONS

Olmesartan-associated enteropathy shares many features with coeliac disease, including symptoms and immunopathogenic pathways, such as increased numbers of CD8+ cells and corresponding overexpression of IL15 by epithelial cells. Taken together, the treatment of epithelial cells with olmesartan medoxomil induces a response by intestinal epithelial cells that is similar to the innate effects of gluten upon the epithelium of coeliac patients.

Sprue-like enteropathy due to olmesartan

A case of spue-like enteropathy due to olmesartan is reported to draw attention to this disease, given the high frequency of use of this drug and the difficulty of diagnosis if the entity if it is not known. In his journal one case was published as Clinical Note in 2014 and we wish to emphasize the importance of knowledge about this relatively new entity.

A Case of Severe Sprue-Like Enteropathy Associated With Valsartan

Olmesartan sprue-like enteropathy is an adverse drug reaction that mimics the appearance of celiac disease and is related to the use of olmesartan. We present the case of a 71-year-old female with severe enteropathy attributed to celiac disease for 5 years that improved only after valsartan cessation. This is the first case associating valsartan with sprue-like enteropathy.