RESUMEN
AIM: Ulcerative colitis (UC) is one of the major forms of chronic relapsing inflammatory bowel diseases. The ability to identify type, severity and responsiveness to therapy of UC using laboratory parameters has long been the aim of clinical studies. The aim of this study was to assess the relation betweenplasma viscosity (PV) and disease activity and response to medical treatment in patients with UC. MATERIAL AND METHODS: The study included 105 patients with UC and 42 healthy volunteers. Blood samples were assessed for PV, erythrocyte sedimentation rate (ESR), high sensitive C-reactive protein (hs-CRP), D-dimer, and fibrinogen. RESULTS: Patients with UC were grouped according to disease activity, i.e. active (n= 59) and remission (n= 46). PV was higher in those with active UC compared with those with UC in remission or healthy subjects. It was significantly higher in both UC refractory to steroid compared to UC responsive to steroid (p< 0.001) and UC refractory to cyclosporine compared to UC responsive cyclosporine (p= 0.003). IncreasedSimple Clinical Colitis Activity Index (SCCAI), Endoscopic Grading Scale (EGS), and Histological Disease Activity (HAD) scores were significantly associated with higher PV in patients with UC. CONCLUSION: PV is a useful marker in predicting response to steroid or cyclosporine treatment in patients with active UC. It could be replaced by ESR or hs-CRP as a measure of the acute phase response in UC since it is sufficiently sensitive. These findings may help identify patients with active UC who will require colectomy. KEY WORDS: Biomarkers, Disease activity, Medical treatment, Steroid-refractory ulcerative colitis, Ulcerative colitis.