What does a fecal calprotectin level of 192 signify?

Fecal Calprotectin of 192 μg/g: Interpretation and Management

What This Level Means

A fecal calprotectin of 192 μg/g falls in the intermediate range (100-250 μg/g) and indicates probable intestinal inflammation requiring further evaluation with either repeat testing or gastroenterology referral, depending on your symptom severity. 1

This level is:

• Above the standard cutoff of 50 μg/g used to rule out inflammatory bowel disease (IBD), making IBD significantly more likely than irritable bowel syndrome (IBS) 2
• Below the 250 μg/g threshold that strongly correlates with active endoscopic inflammation and typically requires treatment intensification 2, 3
• In the "gray zone" where approximately 8% of patients will develop IBD over 12 months, compared to only 1% in those with levels <50 μg/g 2

Immediate Next Steps Based on Your Symptoms

If You Have Moderate to Severe Symptoms

Urgent gastroenterology referral for colonoscopy is warranted. 1 Moderate to severe symptoms include:

• Rectal bleeding with abdominal pain 1
• Significant weight loss 1
• Frequent diarrhea (>6 stools daily) 1
• Severe abdominal pain 1

At this calprotectin level with moderate-severe symptoms, there is a 95.4% probability of finding moderate to severe endoscopic inflammation. 3

If You Have Mild or Minimal Symptoms

Consider repeat calprotectin testing in 2-3 weeks to determine if the elevation is persistent or transient. 1 If the repeat test shows:

• <100 μg/g: Treat as IBS in primary care 1
• Persistently 100-250 μg/g: Refer to gastroenterology for routine evaluation 1
• >250 μg/g: Urgent gastroenterology referral 1

If You Have Alarm Features

Immediate referral via suspected cancer pathway is required regardless of calprotectin level. 1 Alarm features include:

• Rectal bleeding 1
• Iron-deficiency anemia 1
• Unintentional weight loss 1
• Change in bowel habit (age >40) 1

Essential Baseline Testing Before Gastroenterology Referral

Complete these tests in primary care: 1

• Complete blood count (assess for anemia, thrombocytosis indicating inflammation)
• Urea and electrolytes (assess for dehydration, electrolyte abnormalities)
• C-reactive protein (complementary inflammatory marker, though 20% of active Crohn's patients may have normal CRP)
• Celiac screen (tissue transglutaminase antibodies to exclude celiac disease)
• Stool culture (to exclude infectious causes of inflammation)

What Could Be Causing This Elevation

Most Likely: Inflammatory Bowel Disease

At 192 μg/g, IBD (Crohn's disease or ulcerative colitis) is the most probable diagnosis. 2, 4 The sensitivity for detecting endoscopically active IBD at the 50 μg/g cutoff is 90.6%, and your level is nearly 4 times higher. 1

Other Important Causes to Consider

Calprotectin is not specific for IBD and can be elevated in: 2, 1

• Colorectal cancer (colonoscopy will evaluate for this)
• Infectious gastroenteritis (stool culture will help exclude this)
• NSAID use within the past 6 weeks (can falsely elevate levels)
• Microscopic colitis
• Hemorrhoids (can cause false elevation due to local bleeding and inflammation) 1

Critical Caveats

NSAID Use

If you have taken NSAIDs (ibuprofen, naproxen, aspirin) in the past 6 weeks, repeat testing after NSAID cessation is appropriate, as NSAIDs can falsely elevate calprotectin. 1

Specificity Limitations

While calprotectin at this level has moderate specificity (66%) for detecting active endoscopic inflammation, clinical judgment must override biomarkers when alarm features are present. 5, 1

Not Sensitive for Cancer

Calprotectin is not sensitive enough to exclude colorectal cancer, which is why alarm features require cancer pathway referral regardless of calprotectin result. 1

What to Expect at Gastroenterology

The gold standard evaluation will likely include: 1

• Ileocolonoscopy with biopsies to diagnose IBD, assess disease extent and severity, and differentiate Crohn's disease from ulcerative colitis
• Cross-sectional imaging (MRI or CT enterography) may be needed to assess small bowel involvement and complications such as strictures, fistulas, or abscesses

Bottom Line

Your calprotectin of 192 μg/g indicates probable intestinal inflammation that requires further investigation. The urgency depends on your symptom severity: urgent referral for moderate-severe symptoms, repeat testing or routine referral for mild symptoms, and immediate cancer pathway referral for any alarm features. 3, 1 Complete the baseline blood and stool tests while awaiting gastroenterology evaluation, and avoid NSAIDs if possible. 1