C-Reactive Protein: An Alternative Diagnostic Criterion to ESR for Severe Ulcerative Colitis

Researchers sought to identify the equivalent C-reactive protein cutoff for an erythrocyte sedimentation rate greater than 30 mm/h in severe UC.

A cutoff value for C-reactive protein (CRP) of 12 mg/L or greater was found to be a viable alternative to the erythrocyte sedimentation rate (ESR) component of the Truelove and Witts Criteria (TWC) for defining ulcerative colitis (UC) severity. The study findings were published in the Journal of Crohn’s and Colitis.

For the analysis, researchers included patients presenting with UC who satisfied the TWC at the Royal Brisbane and Women’s Hospital in Australia. Patient (n=163) records from 1997 to 2017 were used as the training cohort. For the validation cohort, researchers prospectively enrolled patients (n=128) between 2017 and 2020 or used records from 11 collaborating hospitals between 1997 and 2020. A confusion matrix approach was employed to assess for alternative diagnostic variables.

The training and validation cohorts had a median age of 33 (IQR, 25-43) and 29 (IQR, 22-45) years; 52% and 55% were men; disease duration was 2 (IQR, 1.2-9.2) and 0.2 (IQR, 0-3.0) years (P =6.2´10-11); and 86% and 60% were experiencing a disease relapse (P =1.1´10-6), respectively.

Levels of CRP were tested for their predictive value paired with the ESR cutoff of greater than 30 mm/h. The most accurate (82%) cutoff value was CRP over 12 mg/L with a positive predictive value (PPV) of 85%, negative predictive value of 63%, sensitivity of 95%, and specificity of 35%.

Using the new CRP cutoff for the training set changed the TWC categorization for 18% of patients. Overall, 15 additional patients were categorized as having severe UC, and 4 patients were downgraded to moderate disease.

No significant differences in the corticosteroid failure rate were observed for cohorts using either the ESR or CRP cutoffs among patients who met 2 (P =1), 2 (P =.71), or 4 or more (P =.88) criteria. Similarly, there were no differences in colectomy-by-discharge, fecal calprotectin levels, or Mayo endoscopic subscores for patient groups using the ESR or CRP cutoffs.

For the validation cohort, CRP of 12 mg/L or greater had a sensitivity of 94% and PPV of 83%.

The study may have been limited by its long duration, in which treatment of acute severe UC has advanced over the last 2 decades. The inclusion of patients from the late 1990s may have also introduced bias.

“This work may influence clinical practice by relegating ESR as an admission blood test in acute presentations of UC,” the study authors noted. “Utilizing the CRP-based criteria will improve accessibility to the clinical information required for a complete assessment of the TWC. This will enable a shorter turnaround time for critical decision-making regarding patient disposition and management.”

Disclosure: An author declared affiliations with industry. Please refer to the original article for a full list of disclosures.


Croft A, Lord A, Radford-Smith G. Markers of systemic inflammation in acute attacks of ulcerative colitis: What level of C-reactive protein constitutes severe colitis? J Crohns Colitis. Published online February 11, 2022. doi:10.1093/ecco-jcc/jjac014