Timeframe for Gastroenterology Referral with Significantly Elevated Faecal Calprotectin
A 67-year-old patient with significantly elevated faecal calprotectin indicating severe intestinal inflammation should be seen by gastroenterology urgently, ideally within 2 weeks, with endoscopy performed as soon as feasible thereafter. 1, 2
Rationale for Urgent Referral
Faecal calprotectin >250 μg/g strongly indicates active inflammatory disease requiring immediate investigation, and levels substantially above this threshold (as implied by "significantly elevated" in a symptomatic patient) suggest severe intestinal inflammation with a 95.4% likelihood of true moderate-to-severe endoscopic inflammation. 2, 3
Early endoscopy within 7-30 days is associated with significantly shorter symptom duration (19 vs 47 days) and reduced steroid treatment duration compared to delayed evaluation, making timely referral critical for patient outcomes. 3
The British Society of Gastroenterology recommends that patients with calprotectin levels >250 μg/g warrant urgent referral to gastroenterology for endoscopic assessment. 1
Clinical Context Determines Exact Timing
If Moderate-to-Severe Symptoms Present:
Urgent referral within 1-2 weeks is appropriate, as the combination of significant symptoms with markedly elevated calprotectin has only a 4.6% false positive rate for moderate-to-severe endoscopic inflammation. 2, 3
The American Gastroenterological Association suggests that in patients with moderate to severe symptoms and calprotectin >150 μg/g, treatment adjustment can proceed without initial endoscopy, though endoscopy remains essential for establishing diagnosis in treatment-naïve patients. 4
If Mild or No Symptoms:
Referral within 2-4 weeks is reasonable, though endoscopic assessment should still be prioritized over empiric treatment adjustment in patients with mild symptoms and elevated biomarkers. 4
In asymptomatic patients with known IBD and calprotectin >150 μg/g, there is a 22.4% false positive rate, but endoscopic evaluation should still be considered given the patient's age and need for definitive diagnosis. 2
Pre-Endoscopy Workup to Expedite Care
While awaiting gastroenterology appointment, the following should be completed:
Stool cultures and C. difficile testing to exclude infectious causes, as enteric infections can markedly elevate calprotectin. 3
Complete blood count to assess for anaemia and thrombocytosis indicating inflammation. 1
C-reactive protein (CRP) as a complementary inflammatory marker, though 20% of active Crohn's patients may have normal CRP. 1
Coeliac serology (tissue transglutaminase antibodies) to exclude coeliac disease. 1, 3
Urea and electrolytes to assess for dehydration and electrolyte abnormalities. 1
Critical Caveats
If alarm features are present (rectal bleeding with abdominal pain, change in bowel habit, weight loss, or iron-deficiency anaemia), referral via a suspected cancer pathway is required regardless of calprotectin level, with target assessment within 2 weeks. 1
NSAID use within the past 6 weeks can falsely elevate calprotectin, and this should be documented in the referral, though it should not delay urgent evaluation given the clinical context. 1
Faecal calprotectin is not specific for IBD and can be elevated in infectious gastroenteritis, colorectal cancer, microscopic colitis, and other inflammatory conditions, making endoscopic confirmation essential. 1, 2
Expected Endoscopic Approach
Complete colonoscopy with terminal ileum intubation is preferred over flexible sigmoidoscopy to assess the full extent of disease. 3
Multiple biopsies should be obtained even from normal-appearing mucosa to establish histologic diagnosis. 3
If Crohn's disease is suspected based on initial findings, cross-sectional imaging (MR enterography or CT enterography) may be needed to evaluate small bowel involvement. 1