Checking for elevated fecal calprotectin (FC) levels in patients with spondyloarthritis (SpA), accompanied by an endoscopic and/or radiological study may help in diagnosing inflammatory bowel disease (IBD) among these patients, Zulema Plaza, PhD, MSc, said during her presentation at the ACR Convergence on November 12.

Dr Plaza is with the Fundacion Española de Reumatología in Madrid, Spain.

For the cross-sectional, multicenter, observational EISER study, Dr Plaza and colleagues recruited 559 patients with SpA, all older than 18 years of age. The mean age was 52.2 years; mean age at diagnosis was 42 years; mean time of disease evolution was 12.3 years; and 51% were men. Patients treated with biologics and systemic steroids in the past 30 days were not included, according to Dr Plaza.

FC levels were determined using the Quantum Blue rapid test. Patients with FC ≥80 µg/g underwent an endoscopic study by the gastroenterologist.

The most frequent form of SpA detected was radiographic axial spondyloarthritis (axSpA-r) at 37.0%, followed by peripheral PsA (35.8%).

The study revealed FC≥80 µg/g to be more frequent among patients with axSpA compared to patients with PsA (53% vs 47%) Within the axSpA cohort, FC≥80 µg/g was more prevalent among the axSpA-r group vs axSpA-nr group (80% vs 20%)

Overall, “10.0% of the patients had a family history of IBD and 14.6% had clinical manifestations compatible with IBD; the most common clinical manifestations were asthenia (50.0%), abdominal pain (15.6%) and chronic diarrhea (14.1%),” Dr Zulema said.

The pathological findings after colonoscopies revealed mostly aphthous ulcers (65.9%), superficial ulcers (20.5%), and mucosal erythema (13.6%), mainly located in terminal ileum. Of the 23 patients diagnosed with IBD, 22 had Crohn's disease and 1 had unclassifiable IBD.

Reference:
Plaza Z. 0495: Prevalence of undiagnosed inflammatory bowel disease in patients with spondyloarthritis: EISER study. Presented at: American College of Rheumatology Convergence. November 12, 2023. San Diego.