Case Report
Copyright ©The Author(s) 2016. Published by Baishideng Publishing Group Inc. All rights reserved.
World J Gastrointest Pharmacol Ther. Nov 6, 2016; 7(4): 579-583
Published online Nov 6, 2016. doi: 10.4292/wjgpt.v7.i4.579
Osteonecrosis of both knees in a woman with Crohn's disease
Mara Barbosa, José Cotter
Mara Barbosa, José Cotter, Department of Gastroenterology, Hospital da Senhora da Oliveira, Rua dos Cutileiros, Creixomil, 4835-044 Guimarães, Portugal
Author contributions: The authors made equal contributions to the study; Barbosa M drafted the manuscript; Cotter J critically reviewed the manuscript.
Institutional review board statement: This study was reviewed and approved by Hospital da Senhora da Oliveira Institutional Review Board.
Informed consent statement: Written informed consent was obtained from the patient described in this case report.
Conflict-of-interest statement: Mara Barbosa and José Cotter certify that they have no conflit-of-interest.
Open-Access: This article is an open-access article which was selected by an in-house editor and fully peer-reviewed by external reviewers. It is distributed in accordance with the Creative Commons Attribution Non Commercial (CC BY-NC 4.0) license, which permits others to distribute, remix, adapt, build upon this work non-commercially, and license their derivative works on different terms, provided the original work is properly cited and the use is non-commercial. See: http://creativecommons.org/licenses/by-nc/4.0/
Correspondence to: Mara Barbosa, MD, Department of Gastroenterology, Hospital da Senhora da Oliveira, Creixomil, 4835-044 Guimarães, Portugal. maraisabelbarbosa@net.sapo.pt
Telephone: +351-933-112632 Fax: +351-253-513592
Received: April 11, 2016
Peer-review started: April 13, 2016
First decision: July 20, 2016
Revised: August 7, 2016
Accepted: September 13, 2016
Article in press: September 15, 2016
Published online: November 6, 2016
Processing time: 202 Days and 14.5 Hours
Abstract

Osteonecrosis is a very rare complication of Crohn’s disease (CD). It is not clear if it is related to corticosteroid therapy or if it occurs as an extraintestinal manifestation of inflammatory bowel disease. We present the case of a patient with CD who presented with osteonecrosis of both knees. A 22 years old woman was diagnosed with CD in April 2012 (Montreal Classification A2L1 + L4B3p). She was started on prednisolone (40 mg/d), azathioprine (100 mg/d) and messalazine (3 g/d). In July 2012, due to active perianal disease, infliximab therapy was initiated. In September 2012, she had a pelvic abscess complicated by peritonitis and an ileal segmental resection and right hemicolectomy were performed. In December 2012 she was diagnosed with bilateral septic arthritis of both knees with walking impairment. She was treated with amoxicillin-clavulanic acid, started a physical rehabilitation program and progressively improved. However, then, bilateral knee pain exacerbated by movement developed. Magnetic resonance imaging showed multiple osseous medullary infarcts in the distal extremity of the femurs, proximal extremity of the tibiae and patellas and no signs of subchondral collapse, which is consistent with osteonecrosis. The patient recovered completely and maintains therapy with azathioprine and messalazine. A review of the literature is also done.

Keywords: Osteonecrosis; Knee; Inflammatory bowel disease; Crohn’s disease; Magnetic resonance imaging

Core tip: Although very rare, osteonecrosis is a devasting event that can occur in Crohn’s disease (CD). We present the case of a 22 years old woman with CD who was diagnosed with osteonecrosis of both knees. As we demonstrate with this report, awareness of risk factors, such as corticosteroid therapy and inflammatory bowel disease activity, is crucial to establish the diagnosis of this inflammatory bowel disease rheumatological complication. Prompt treatment is recommended. A review of the literature is also presented.