Soluble urokinase plasminogen activator receptor suPAR as a marker for inflammation in pediatric inflammatory bowel disease

Abstract

Objective. In inflammatory bowel disease (IBD), more means to monitor early therapeutic response are needed. In pediatric IBD, blood inflammatory markers erythrocyte sedimentation rate (ESR) or C-reactive protein (CRP) may be low in 10 to 20% of patients with severe disease. Recently, soluble urokinase plasminogen activator receptor (suPAR) was described as a potential blood inflammatory marker in adult IBD. Methods. We tested the performance of suPAR by the start of therapy with glucocorticoids (n = 19) or TNF-α-antagonist (n = 16) in pediatric IBD (Crohn's disease n = 19, ulcerative colitis (UC) n = 16). Results. The levels of suPAR were low in both patient groups studied. There was no difference in the values regarding the presence of Crohn's disease or ulcerative colitis. Thus, all analyses were performed on the entire sample set. Glucocorticoid therapy, however, resulted in a significant decline in suPAR levels from a median of 3.06 to 2.54 ng/ml (p < 0.01). In contrast, TNF-α-antagonist had no effect. The suPAR levels did not associate with ESR or CRP or fecal calprotectin (FC). Conclusions. In pediatric IBD, the suPAR levels in blood are low and do not reflect the level of intestinal inflammation assessed with FC. The introduction of corticoids, however, results in a decline of suPAR levels in blood but not reflect therapeutic response to TNF-α-antagonist. Thus, suPAR is of limited value in assessing systemic inflammatory responses in pediatric IBD.

Key Words::

• children
• colitis
• Crohn's disease
• inflammatory biomarkers
• ulcerative

Acknowledgements

Ms Anna Lindahl and Mr Leevi Haapanen are thanked for assistance in organizing the patient data. The study was supported by the Finnish Pediatric Research Foundation Helsinki (KLK), Clinical Graduate School in Pediatrics and Obstetrics/Gynecology, University of Helsinki (HR) and University Central Hospital Research Fund (KLK).

Declaration of interest: Finnish Pediatric Research Foundation Helsinki (KLK), Clinical Graduate School in Pediatrics and Obstetrics/Gynecology, University of Helsinki (HR) and University Central Hospital Research Fund (KLK). There is no conflict of financial interest.