Hypersensitivity to 5-ASA suppositories

Recurrent Eosinophilic Pneumonia Associated with Mesalazine Suppository in a Patient with Ulcerative Colitis

Mesalazine suppositories are widely used to treat ulcerative colitis and have a guaranteed safety profile, but although rare, they can cause pulmonary toxicity. A 35-year-old woman with ulcerative colitis was diagnosed to have acute eosinophilic pneumonia after 29 days of oral mesalazine use and improved after mesalazine and corticosteroid were withdrawn. Reintroduction of mesalazine suppositories resulted in acute eosinophilic pneumonia recurrence after 28 days. Mesalazine re-administration (even via a different route) in patients with a history of mesalazine-induced eosinophilic pneumonia should be undertaken cautiously, because eosinophilic pneumonia may recurrence.

Acute eosinophilic pneumonia related to a mesalazine suppository

It has been well known that mesalazine can cause the interstitial lung disease, such as Bronchiolitis obliterans with organizing pneumonia (BOOP), Non-Specific Interstitial Pneumonia (NSIP), or eosinophilic pneumonia. 5-Aminosalicylic acid (5-ASA), mesalazine, and sulfasalazine are important drugs for treating inflammatory bowel disease. Topical products of these limited systemic absorption and have less frequent side effects, therefore suppository form of these drugs have been used more than systemic drug. Most cases of measalzine-induced lung toxicity develop from systemic use of the drug. A 30-year-old woman had an interstitial lung disease after using mesalazine suppository because of ulcerative colitis. The lung biopsy demonstrated eosinophilic pneumonia combined with BOOP. She was recovered after stopping of mesalazine suppository and treatment with systemic steroid.

Pitfalls in the interpretation of nonneoplastic mucosal biopsies in inflammatory bowel disease

This review provides a summary of common diagnostic problems encountered by both pathologists and gastroenterologists when evaluating patients with diarrhea and in whom inflammatory bowel disease (IBD) is suspected. The two most common forms of IBD, ulcerative colitis (UC) and Crohn's disease (CD), may, in certain settings, show overlapping endoscopic and pathologic features, potentially resulting in diagnostic confusion. For instance, some cases of UC may show unusual CD-like features, such as rectal sparing, discontinuous disease, aphthous ulceration, ileal or extracolonic involvement, and granulomatous inflammation, all of which may be evident in mucosal biopsy specimens. CD may also present as a diffuse, superficial pancolitis with ileal sparing that mimics the endoscopic and histologic appearance of UC. Furthermore, other forms of colitis, such as microscopic colitis, diverticulitis, diversion colitis, and nonsteroidal anti-inflammatory drug (NSAID)-induced colonic injury may also show IBD-like changes in mucosal biopsies. The potential diagnostic pitfalls faced by physicians, as well as features that aid in the distinction among these entities, are discussed in detail in this review.