title: Isotretinoin-induced inflammatory bowel disease in an adolescent.
abstract: OBJECTIVE
  To report a case of inflammatory bowel disease (IBD) associated with use of isotretinoin.
  
  
  METHODS
  17-year-old boy presented with new-onset rectal bleeding after completion of a five-month course of isotretinoin. A diagnosis of ulcerative colitis was made. His condition worsened despite therapy with 5-aminosalicylic acid, steroid retention enema, iron supplement, and prednisone. Five months after the onset of rectal bleeding, he had lost 11.4 kgand developed bilateral pitting edema of the hips and profound anemia. A subtotal colectomy and ileostomy was performed.
  
  
  CONCLUSIONS
  Rectal bleeding has been reported to occur during or up to several years after treatment with isotretinoin. The mechanism by which isotretinoin may induce IBD is unknown. Proposed mechanisms include inhibition of epithelial cell growth resulting in ulceration and inflammation of the gut mucosa, inhibition of glycoprotein synthesis affecting the integrity of the mucosal wall, and stimulation of kiler T cells, leading to epithelial cell injury and a resultant inflammatory response.
  
  
  CONCLUSIONS
  This case of probable isotretinoin-induced IBD suggests that patients with suspected IBD should be asked about current or past use of isotretinoin to improve documentation of this serious adverse event.
authors.affiliation: Pharmacy Department, London Health Sciences Centre, Ontario, Canada. denise.reniers@lhsc.on ca
authors.forename: D E
authors.initials: DE
authors.lastname: Reniers
authors.forename: J M
authors.initials: JM
authors.lastname: Howard
mesh_terms: D000152:Acne Vulgaris / Q000188:drug therapy*; D000293:Adolescent; D000328:Adult; D003093:Colitis, Ulcerative / Q000139:chemically induced / Q000601:surgery; D005260:Female; D006801:Humans; D015212:Inflammatory Bowel Diseases / Q000139:chemically induced*; D015474:Isotretinoin / Q000009:adverse effects*; D008297:Male; D015431:Weight Loss
chemical_list: D015474:Isotretinoin