Tumor necrosis factor inhibitors are effective and recommended in treating patients with coexisting spondyloarthritis (SpA) and ulcerative colitis (UC); however, the evidence of their superiority over other drugs is insufficient.1 Although Janus kinase inhibitors (JAKi) have shown effectiveness in treating UC and psoriatic arthritis, there are no reports of treating coexisting SpA and UC with JAKi monotherapy.

A 37-year-old male patient with a 1-year history of UC, treated with salazosulfapyridine (1500 mg/day), presented with persistent pain in the neck, both elbows, and ankle joints. Blood tests revealed anemia, with a hemoglobin level of 9.7 mg/dL, and elevated C-reactive protein (CRP) at 12.06 mg/dL; no specific autoantibodies were detected. Cervical magnetic resonance imaging (MRI) showed spondylitis with erector spinae muscle inflammation around the vertebral columns (Figure 1A), and ultrasound showed synovitis and enthesitis in both elbows, wrists, and ankle joints. Additionally, colonoscopy confirmed active and severe status of left side colitis (Figure 1C). We diagnosed the patient with coexisting peripheral and axial SpA and UC. Given the active and severe state of his UC, peripheral SpA, and axial SpA, we initiated treatment with the JAKi upadacitinib at 45 mg/day. After 6 weeks of treatment, blood tests showed normalized levels of hemoglobin and CRP. MRI showed resolved SpA inflammation (Figure 1B), ultrasound showed resolved arthritis, and colonoscopy showed healing ulcers (Figure 1D).

Cervical MRI showed (A) spondylitis with erector spinae muscle inflammation around the vertebral columns (arrows) before treatment, and (B) resolved spondylitis inflammation (arrows) after treatment. (C) Colonoscopy revealed ulcerative colitis on the left side with UCEIS2 of 8. (D) After treatment, colonoscopy showed healed ulcers and a decrease in UCEIS to 0. MRI: magnetic resonance imaging; UCEIS: Ulcerative Colitis Endoscopic Index of Severity.

As our case demonstrates, JAKi may be an effective and useful choice for the treatment of coexisting SpA and UC.