Saam Dilmaghani, Camille Lupianez-Merly, Joelle BouSaba, Priya Vijayvargiya, Irene Busciglio, Monique Ferber, Paula Carlson, Leslie J Donato, Michael Camilleri
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引用次数: 0
Abstract
Background and aims: Diagnosis of bile acid diarrhea (BAD) has been based on 48-hour fecal BA excretion; serum 7αC4 (C4) has been used to screen for BAD. Optimal diagnostic cutoffs for C4 and biochemical measurements in a single stool sample are unknown. We sought to examine the relationship between total BA concentration (TBAc) and percent primary BA (%PBA) in a single stool sample and serum C4 in patients with and without BAD and explore performance characteristics of stool consistency and biochemical (serum C4 and single-stool BA) parameters for diagnosis of BAD compared with gold standard 48-hour fecal BA.
Methods: Based on data from patients with BAD, irritable bowel syndrome with diarrhea (IBS-D), and healthy control subjects, we assessed correlations among stool and serum measurements. Machine learning models (based on data from 30 patients with BAD, 8 patients with IBS-D, and 26 healthy control subjects) were trained on 25 bootstrapped random samples, the superior model was identified, and optimal cutoffs of biological measurements to diagnose BAD were summarized.
Results: There were correlations between serum C4 and %PBA (R = 0.284, P < .001), and between %PBA and TBAc (R = 0.49, P < .001). Using a %PBA of 1.05% (25th percentile in BAD), the %PBA distinguished BAD from IBS-D (odds ratio, 3.06; 95% confidence interval, 1.35-7.46; P = .01). The multivariate logistic regression model had superior balance of variance and bias. Optimal cutoffs for predicting BAD using logistic regression were 4.5% PBA (P = .023) and 1.88 μmol/g TBAc (P = .016). Serum C4 >24 ng/mL and PBA >4.6% individually had 57% and 75.8% positive predictive value, respectively, but together had a 90.1% positive predictive value. Stool consistency was less informative.
Conclusions: New diagnostic cutoffs based on serum C4 and single-stool TBAc and % PBA provide potential alternatives for diagnosing BAD. Further validation is warranted.
期刊介绍:
Clinical Gastroenterology and Hepatology (CGH) is dedicated to offering readers a comprehensive exploration of themes in clinical gastroenterology and hepatology. Encompassing diagnostic, endoscopic, interventional, and therapeutic advances, the journal covers areas such as cancer, inflammatory diseases, functional gastrointestinal disorders, nutrition, absorption, and secretion.
As a peer-reviewed publication, CGH features original articles and scholarly reviews, ensuring immediate relevance to the practice of gastroenterology and hepatology. Beyond peer-reviewed content, the journal includes invited key reviews and articles on endoscopy/practice-based technology, health-care policy, and practice management. Multimedia elements, including images, video abstracts, and podcasts, enhance the reader's experience. CGH remains actively engaged with its audience through updates and commentary shared via platforms such as Facebook and Twitter.