JAK inhibitor, a new player for treatment-refractory microscopic colitis

Journal article

Informed consent has been obtained. Rheumatoid arthritis was diagnosed and treated conventionally with steroids, nonsteroidal inflammatory drugs and methotrexate. A decreased vascular colonic pattern was observed during endoscopy while histologic evaluation showed both an increased number of inflammatory cells within the lamina propria and increased intraepithelial CD3 positive lymphocytes revealing a diagnosis of LC.Nonsteroidal therapy was reduced when the diagnosis of LC was made. She was not receiving any other medication. Budesonide and systemic corticosteroids (prednisolone up to 20 mg/day) had no effect on the diarrhea. After 12 months, anti-TNF therapy was started for her rheumatoid arthritis but this also had no impact on the diarrhea. Diarrhea persisted, with a substantial effect on her quality of life, as did LC, confirmed histologically (no fewer than 5 procedures over 4 years), until her rheumatoid arthritis lost response to anti-TNF therapy. To offer better control of the rheumatoid condition, she was then switched to upadacitinib (UPA), a selective Janus kinase inhibitor-1 (JAK 1) inhibitor (15 mg once daily) and unexpectedly, her diarrhea resolved within days. Endoscopic evaluation 5 months after UPA initiation revealed a normal mucosa and complete normalization of the histologic lesions. Sixteen months after initiation, the patient remains free of diarrhea and continues UPA 15 mg/day. The etiology and pathophysiology of MC are not well understood but MC shows a T-helper 1 (Th1) mucosal cytokine profile. Interferon- (IFN-) is the dominant cytokine in CC, but TNF- in LC, together with increased mRNA levels of interleukin (IL)-8 and IL-15. 5There is also evidence of a mixed.

Authors: Druez, A; Travis, S; Rahier, J-F

• Publication status: Published
• Peer review status: Peer reviewed
• Publisher: Korean Association for the Study of Intestinal Diseases
• Journal: Intestinal Research
• Volume: 21
• Issue: 3
• Pages: 411-412
• Publication date: 2023-07-03
• DOI: 10.5217/ir.2023.00030
• EISSN: 2288-1956
• ISSN: 1598-9100
• Language: English
• Keywords: Inflammatory bowel disease; Microscopic colitis; Disease; Gastroenterology; Medicine; Colitis; Refractory (planetary science); Internal medicine