In a real-life setting, fecal calprotectin (FC) home testing performed well at predicting disease endoscopic activity in patients with inflammatory bowel disease (IBD) being treated with adalimumab.
The study published in the European Journal of Gastroenterology & Hepatology, could be a boon to patients and physicians employing the treat-to-target (T2T) strategy, which relies on disease monitoring through methods like endoscopy, histology, and serum and fecal biomarkers.
One goal of T2T is to identify patients who are asymptomatic in order to prevent or minimize flare-ups. Colonoscopy is the preferred approach for achieving this, but cost, risk, and patient reluctance limit its use. FC has gained attention in recent years, as it outperforms serum biomarkers in its correlation with clinical, endoscopic, and histological disease activity. Consecutive FC measurements predict disease relapse among asymptomatic patients with high specificity and sensitivity. There’s also evidence that it could be useful for perioperative monitoring.
FC is typically assessed in a lab, but the recent availability of smartphone-based tests has allowed patients to collect and test their stool at home. The method has been tested through clinical research, but real-world data have so far been lacking.
First Real-Life Results
In what they described as the first real-life study of its kind, researchers offered at-home FC testing every 4 months to all 72 current IBD patients taking adalimumab at the University Hospital of Heraklion, University of Crete, Irakleio, Greece; seven patients (10%) declined to take part in at-home FC testing. Of the remaining 65, the mean age was 42.3 years, and 58% were male; 89% had a diagnosis of Crohn’s disease. The mean disease duration was 13.3 years.
Abnormal FC values were confirmed with a follow-up test 1 month later, after which point a colonoscopy was scheduled to inform treatment modification. Twenty-four patients (37% of the population) had two positive tests, and 19 who were able underwent colonoscopy. Twelve patients (19%) underwent adalimumab dose intensification, 9 (14%) switched to a different biologic, and 2 (3%) had surgery.
The group of patients who required treatment modification had a significantly higher median FC concentration of 761 mcg/g (37% had values ≥ 1,000 mcg/g), compared with a median concentration of 108 mcg/g for those who did not have their dose modified (P < .0001). With a cutoff of 250 mcg/g, FC correctly identified a need for treatment with an area under the receiver operating characteristic curve (AUC) value of 0.90 (95% confidence interval, 0.80-0.96).
FC was significantly correlated to endoscopic activity (r = 0.543, P < .001), and patients with endoscopic disease had higher median FC concentrations (689 vs. 99 mcg/g; P < .001).
The researchers calculated that a cutoff value of FC levels greater than 413 mcg/g is optimal for predicting endoscopic disease, with a sensitivity of 75%, a specificity of 76%, a positive likelihood ratio of 3.12, and a negative likelihood ratio of 0.33.
Diabeteslike Home Monitoring for IBD?
"Home monitoring of disease activity and drug levels will be a paradigm shift in management of IBD, because it will place in the patient’s hands the opportunity to assess their disease activity and to have a better understanding of what’s going on when they have symptoms or concerns about their disease control," commented David Rubin, MD, who did not participate in the study.
He noted that patients are often unsure whether a new symptom is the beginning of another episode of IBD or something unrelated.
"One of the biggest challenges of having IBD is just the perception of loss of control of the disease and knowing when things are going to happen," said Rubin, a professor of medicine and the codirector of the digestive diseases center at the University of Chicago, and the chair of the scientific advisory committee for the Crohn’s & Colitis Foundation. "I often explain to people that using a tool like this would be similar to patients with diabetes checking their blood sugar – getting a feel for what’s actually happening closer to the time that it’s happening, rather than waiting for it to progress. I really think that the general idea of home monitoring is going to be a major advance in our field."
Although the new study proved the technique’s acceptability and efficacy, it isn’t without pitfalls, according to Rubin. False positives or negatives are a concern, and other factors might influence the results. For example, proton pump inhibitors can increase FC levels. Another concern is that some patients can become obsessed with their FC levels, and may want to test themselves at any sign of illness. They may develop unrealistic expectations about the impact of medications on their FC levels.
"That’s going to open up a whole dialogue with people, so that we all are on the same page about it. But I think that the benefits of having this far outweigh those potential risks," said Rubin.
The authors reported no conflicts of interest. Rubin has consulted for TECHLAB.
This article originally appeared on MDedge.com, part of the Medscape Professional Network.
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Cite this: At-Home Fecal Calprotectin Test for IBD Shows Real-World Efficacy - Medscape - Aug 24, 2021.