Elevated urinary orosomucoid excretion as a novel biomarker in Crohn's disease.

BACKGROUND: Laboratory markers are essential tools in the follow-up of patients with Crohn's disease (CD). Our aim was to investigate urinary concentrations of orosomucoid in relation to the inflammatory activity of CD and to compare it with clinical indices and conventional laboratory parameters.

MATERIALS AND METHODS: Blood and urine samples of 86 patients (55 adults and 31 children) with CD and 68 healthy individuals (38 adults and 30 children) as controls were analyzed. Patients were categorized according to their clinical scores (Harvey-Bradshaw Index (HBI) or Pediatric Crohn's Disease Activity Index (PCDAI)). Urinary orosomucoid (u-ORM) was determined by automated immune turbidimetric assay and values were referred to urinary creatinine (u-ORM/u-CREAT, mg/mmol).

RESULTS: U-ORM/u-CREAT values were 7 times higher in children with active CD (0.50 vs. 0.07 mg/mmol, p<0.001) and 2 times higher in adults (0.32 vs. 0.14 mg/mmol, p=0.01) compared with patients with inactive disease. U-ORM/u-CREAT showed good correlation with conventional inflammatory markers (hs-CRP, serum ORM; p<0.01) and activity indices (HBI, p=0.018; PCDAI, p<0.001). U-ORM/u-CREAT had similar discriminative performance to hs-CRP and serum ORM in the differentiation of active from inactive pediatric CD patients.

CONCLUSIONS: Our findings suggest that u-ORM/u-CREAT might serve as a valuable additional marker in the follow-up of CD patients, especially in children for whom the non-invasive sampling is a further advantage. This article is protected by copyright. All rights reserved.