Table 5

Potential monitoring of patients with CD in clinical remission

QuestionMonitoring toolPrediction (95% CI)
Has mucosal healing been achieved?CRP ≤10 mg/l and faecal calprotectin ≤200 μg/gCDEIS ≤3 with a sensitivity of 78% and specificity of 58%57
What is the risk of relapse?Increased CRP
Increased faecal calprotectin

Mucosal healing at ileocolonoscopy (SESCD=0)
Relative risk of relapse increasing to 3–58*70–72
Clinical relapse over 1 year with a sensitivity of 43–90% and a specificity of 43–88% (depending on the threshold for faecal calprotectin)*67–69
69% of remission without steroids over the next 2 years (compared with 38% if no mucosal healing)19
What is the risk of abdominal surgery?Mucosal healing at ileocolonoscopy (at least partial)14% requiring abdominal surgery (vs 38% if absence of healing)4
What is the risk of relapse upon anti-TNF withdrawal?CRP ≥5 mg/l
Faecal calprotectin ≥300 μg/g
Absence of mucosal healing at ileocolonoscopy (CDEIS >0)
HR for relapse 2.5 (1.4–4.4)21
HR for relapse 3.2 (1.7–6.2)21
HR for relapse 1.8 (1.0–3.3)21
What is the risk of postoperative clinical recurrence?Endoscopic Rutgeerts score within 6–12 months after surgical resectioni0–i1: 10% of relapse at 8 years22
i2: 40% of relapse at 8 years22
i3–i4: 90% of relapse at 8 years22
  • *Increase in CRP and faecal calprotectin occurs within the 4–6 months before relapse.73

  • CD, Crohn's disease; CDEIS, CD Endoscopic Index of Severity; CRP, C-reactive protein; SESCD, Simplified Endoscopic Score of CD; TNF, tumour necrosis factor.