From the Guidelines
A very high calprotectin level in a patient with diarrhea strongly indicates active intestinal inflammation, most commonly inflammatory bowel disease (IBD) such as Crohn's disease or ulcerative colitis. According to the most recent and highest quality study, a threshold value of 50 μg/g for fecal calprotectin is recommended to optimize sensitivity for IBD 1. However, levels above 250 μg/g are considered significantly elevated, with values exceeding 1000 μg/g suggesting severe active inflammation 1. This finding warrants prompt referral to a gastroenterologist for further evaluation, including colonoscopy with biopsies to confirm the diagnosis and determine the extent and severity of inflammation.
Some key points to consider in the management of a patient with a very high calprotectin level and diarrhea include:
- The need for distinction between IBD and infectious causes of diarrhea, as treatment approaches differ significantly
- The potential use of antidiarrheal medications like loperamide for mild symptoms, though these should be avoided if severe inflammation is suspected due to risk of toxic megacolon
- The importance of stool cultures and other infectious workup to rule out infectious causes
- The role of calprotectin in reflecting the underlying pathophysiology of IBD, which involves immune dysregulation leading to mucosal damage and inflammation in the intestinal tract 1.
It's crucial to prioritize the patient's morbidity, mortality, and quality of life when managing a very high calprotectin level and diarrhea, and to base management decisions on the most recent and highest quality evidence available 1.
From the Research
Very High Calprotectin Level in Diarrhea
A very high calprotectin level in a patient with diarrhea can indicate several things:
- Inflammatory bowel disease (IBD) should be suspected in any patient presenting with chronic or recurrent abdominal pain and diarrhea, as stated in the study 2.
- Elevated fecal calprotectin levels are associated with intestinal inflammation, and the level of calprotectin can correlate with the degree of inflammation, as mentioned in the studies 3, 4, 5.
- A very high calprotectin level can suggest active inflammation in the gastrointestinal tract, which may require further testing, such as colonoscopy, to confirm the diagnosis, as recommended in the study 4.
- The level of calprotectin can also be used to monitor disease activity and predict disease relapse in patients with IBD, as discussed in the studies 2, 5.
Clinical Spectrum of High Fecal Calprotectin Levels
The clinical spectrum of patients with high fecal calprotectin levels can include:
- Diarrhea, abdominal cramps, and weight loss, which were the most common complaints noted in patients with high fecal calprotectin levels, as reported in the study 6.
- IBD patients tend to have higher fecal calprotectin levels compared to normal subjects, as shown in the study 6.
- The level of calprotectin can vary among patients with different diagnoses, and it can be used to distinguish between inflammatory and non-inflammatory gastrointestinal conditions, as mentioned in the studies 3, 4, 5.
Interpretation of Fecal Calprotectin Levels
The interpretation of fecal calprotectin levels can be as follows:
- Levels <50 µg/g to 100 µg/g: quiescent disease is likely, and therapy should be continued, as suggested in the study 4.
- Levels >100 µg/g to 250 µg/g: inflammation is possible, and further testing is required to confirm inflammation, as recommended in the study 4.
- Levels >250 µg/g: active inflammation is likely, and strategies to control inflammation should be initiated, as suggested in the study 4.