High CRP or CRP–albumin ratio on admission predicts risk of steroid-refractory ASUC

An elevated C-reactive protein (CRP) or CRP–albumin ratio on admission is significantly associated with the risk of steroid-refractory disease in patients with acute severe ulcerative colitis (ASUC), suggests a Singapore study.

Furthermore, those with hypoalbuminaemia on admission and using biologics at presentation have greater odds of requiring colectomy in the first year after admission for ASUC.

“Patients with ASUC who have elevated CRP or CRP–albumin ratio on admission should be considered at risk for steroid-refractory disease,” the researchers said. 

This retrospective cohort study involved 58 admissions for ASUC among 47 patients between August 2002 and January 2022. The researchers assessed serum biomarkers measured on admission and examined the primary outcomes, namely the need for rescue therapy during the same admission and colectomy within 1 year of admission.

Rescue therapy with infliximab was administered in 20 (34.5 percent) of the 58 admissions, while colectomy was performed within 1 year for nine (15.5 percent) of the admissions. [Singapore Med J  2025;66:449-445]

An elevated CRP of >30 mg/L (relative risk [RR], 1.63), a CRP–albumin ratio of >0.85 (RR, 1.63), and a composite factor of both CRP >30 mg/L and age ≥60 years (RR, 2.37) significantly correlated with the need for rescue therapy.

Moreover, hypoalbuminaemia ≤25 g/L (RR, 4.35) and the use of biologics at presentation (RR, 1.54) were predictive of requiring colectomy within 1 year of admission, but a CRP of ≥80 mg/L appears to confer protective benefits (RR, 0.70).

Systemic inflammation

“CRP is a marker of systemic inflammation and is often elevated in ASUC,” the researchers said. “A raised CRP of >100 mg/L had a positive predictive value of 80 percent to 100 percent for deep ulcers in active ulcerative colitis.” [Dig Liver Dis 2023;55:1194-1200]

To predict corticosteroid failure in ASUC, the Oxford criteria use a CRP of >45 mg/L at day 3 to indicate an elevated risk, while the ADMIT-ASC index uses a CRP of ≥100 mg/L. [Gut 1996;38:905-910; Gut 2023;72:433-442]

In another study conducted by French researchers Le Baut and colleagues, a scoring system was developed to identify patients at high risk for colectomy within 1 year of admission for ASUC. This novel system used a CRP of >30 mg/L measured on the day of admission as a predictive factor. [Clin Gastroenterol Hepatol 2021;19:1602–1610.e1]

“In our study, we found that a CRP of >30 mg/L was significantly associated with corticosteroid failure and the need for rescue therapy, but not colectomy,” the researchers said. 

“It was surprising that an even higher CRP of >80 mg/L showed a protective rather than prognostic impact on the need for colectomy. We postulate that the prognostic impact of CRP on the need for colectomy may be variable, depending on other factors such as advanced age and poor nutritional status,” they added.

Moreover, a very high CRP level may have resulted in earlier escalation of therapy, thus reducing the odds or requiring colectomy, according to the researchers. 

“We did not find any significant association between CRP level and either age or albumin level in our study,” they said.