Prevalence of, and predictors of, bile acid diarrhea in outpatients with chronic diarrhea: A follow-up study

Risk of cancer in patients with bile acid diarrhoea: a Danish nationwide matched cohort study

OBJECTIVE

Bile acid diarrhoea is a common cause of chronic diarrhoea. Increased levels of potentially carcinogenic bile acids in faeces, theoretically, may increase the risk of colorectal cancer in particular, but the long-term disease course is unknown. We aimed to investigate the overall and site-specific cancer risk in bile acid diarrhoea.

DESIGN

Adult patients with bile acid diarrhoea were identified using nationwide Danish registries from 2003 to 2020 by a diagnostic gold-standard 75-selenium tauroselcholic acid procedure followed within 6 months by sequestrant prescription. The risk of overall and site-specific cancers in cases with bile acid diarrhoea was compared with sex, age and comorbidity-adjusted matched controls. A competing risk model estimated cumulative incidence functions and cause-specific HRs.

RESULTS

We identified 2260 patients with bile acid diarrhoea with a mean follow-up of 5.5 years (SD 4.2). The overall cancer risk was increased by an HR of 1.32 (95% CI 1.12 to 1.54). The risk of site-specific cancer was increased in 3 of 10 cancer groups: haematological, HR 2.41 (1.36 to 4.02); skin, HR 1.33 (1.01 to 1.71); and male genital cancers, HR 1.85 (1.11 to 2.92). No increased risk of colorectal cancer was detected in patients with bile acid diarrhoea, HR 0.73 (0.34 to 1.63).

CONCLUSIONS

Bile acid diarrhoea was associated with an increased overall risk of cancer, especially haematological cancers, but the risk of colorectal cancer was not increased. The lack of a diagnostic code for bile acid diarrhoea and potential residual confounding are limitations, and the findings should be replicated in other cohorts.

Diagnosis and treatment of post-cholecystectomy diarrhoea

The incidence of cholecystitis is relatively high in developed countries and may usually be attributed to gallstones, the treatment for which involves complete surgical removal of the gallbladder (cholecystectomy). Bile acids produced following cholecystectomy continue to flow into the duodenum but are poorly absorbed by the colon. Excessive bile acids in the colon stimulate mucosal secretion of water and electrolytes leading, in severe cases, to diarrhoea. Bile acid diarrhoea (BAD) is difficult to diagnose, requiring a comprehensive medical history and physical examination in combination with laboratory evaluation. The current work reviews the diagnosis and treatment of BAD following cholecystectomy.

Prevalence and impact of Rome IV versus Rome III irritable bowel syndrome in patients with inflammatory bowel disease

BACKGROUND

Irritable bowel syndrome (IBS)-type symptoms are common in inflammatory bowel disease (IBD), but few studies have examined the prevalence and impact of IBS-type symptoms in IBD according to Rome IV criteria.

METHODS

We collected demographic, symptom (Rome III, Rome IV, and clinical disease activity indices), psychological (anxiety, depression, and somatization), and quality of life data from 973 IBD patients. Medical records were reviewed to document disease type, extent/location, behavior, medical therapy, and antidepressant or opioid use. We compared characteristics of individuals with no IBS-type symptoms, Rome III IBS-type symptoms, and Rome IV IBS-type symptoms.

KEY RESULTS

In total, 302 (31.0%) patients met the Rome III criteria for IBS, and 172 (17.7%) met Rome IV criteria. Those with IBS-type symptoms were younger, more likely to be female, and had higher rates of antidepressant (p = 0.006) or opioid use (p = 0.001). Rome IV IBS-type symptoms were associated with symptoms of mood disorders, flare of disease activity, and lower quality of life scores (p < 0.001 for all analyses). Compared with Rome III criteria, those with Rome IV IBS-type symptoms had significantly higher rates of anxiety (p < 0.001), depression (p = 0.002), and somatization (p < 0.001), lower quality of life scores (p < 0.001) and were more likely to have CD (p = 0.011), with ileal distribution (p = 0.006).

CONCLUSIONS AND INFERENCES

Rome IV IBS-type symptoms are associated with increased psychological co-morbidity, lower quality of life scores, and higher rates of antidepressant or opioid use. This is a cohort potentially at risk of adverse clinical outcomes and should be a focus for future research.

Bile Acid Diarrhea in Adults and Adolescents

BACKGROUND

Bile acids are central to enterohepatic signaling pathways activated through natural receptors, farnesoid X receptor [FXR mediates synthesis of fibroblast growth factor-19 (FGF-19)], and G protein-coupled bile acid receptor 1 (GPBAR1, also known as TGR5). Although bile acid diarrhea (BAD) is more commonly encountered in ileal resection or disease, there is evidence documenting "idiopathic" BAD in about 20% of adolescents and 30% of adults presenting with chronic, non-bloody diarrhea often attributed to irritable bowel syndrome. Mechanism(s) leading to increased hepatic synthesis and colonic bile acid levels in "idiopathic" BAD include reduced synthesis of FGF-19 by the ileal mucosa, or genetic variation in hepatocyte proteins klotho β and FGF receptor 4 (FGFR4) that mediate negative feedback of bile acid synthesis.

PURPOSE

The objective of this review is to summarize the diagnosis of BAD in adults and adolescents. In addition to ⁷⁵ SeHCAT retention for diagnosis of BAD, studies have validated fasting serum 7αC4 and FGF-19, respectively, by-product and inhibitor of hepatic bile acid synthesis, as well as fecal bile acid measurements. These assays are widely available through reference laboratories, and they are being simplified (eg, measurement of primary fecal bile acids in a random stool sample). BAD has also been identified as a co-factor contributing to persistent diarrhea in other diseases in remission including inflammatory bowel disease, microscopic colitis, celiac disease, and neuroendocrine tumors. In summary, advances in diagnosis of BAD provide opportunities for generalists and pediatric and adult gastroenterologists to provide targeted treatment for BAD presenting as chronic non-bloody diarrhea.

Downregulation of Serum and Distal Ileum Fibroblast Growth Factor19 in Bile Acid Diarrhoea Patients

BACKGROUND

Bile acid diarrhoea or BAD is a common but little recognised cause of chronic diarrhoea. Few of these patients in China have been diagnosed due to a lack of diagnostic options.

AIMS

To clarify the diagnostic value of serum fibroblast growth factor19 (FGF19) in BAD patients.

METHODS

We reported on 60 chronic diarrhoea patients and 80 healthy volunteers (HV). Based on the 90th percentile levels of serum 7a-hydroxy-4-cholesten-3-one (C4) of HV, these patients were divided into BAD group (C4 ≥ 90th) and non-bile acid diarrhoea group (NBAD, C4 < 90th). Serum FGF19 in the two clinical groups and HV group were compared, as was distal ileum FGF19 in clinical groups. The diagnostic value of serum FGF19 for BAD was evaluated.

RESULTS

The 90th percentile of serum C4 in HV group was 65.87 ng/ml. Serum FGF19 concentrations in BAD group (Median 69.28 pg/ml; n = 23) were significantly lower than those in HV (Median 122.18 pg/ml; n = 80) and NBAD (Median 129.57 pg/ml; n = 29) groups. FGF19 mRNA of the distal ileum in BAD group, was lower than that in NBAD group, P = 0.002. The rate of FGF19 protein low expression of distal ileum in BAD and NBAD group were 78.3% and 48.3%, P = 0.027. Using an ROC curve, statistical analysis yielded a threshold FGF19 concentration of 117.3 pg/ml (AUC, 0.906; 91.3% sensitivity, 79.3% specificity) for a clinical diagnosis of BAD.

CONCLUSIONS

Serum and distal ileum expression of FGF19 significantly decreased in BAD patients. The suggested clinical ranges for serum FGF19 < 117.3 pg/ml has high sensitivity and specificity for BAD patients with a normal structural and histological ileum.

Prevalence and clinical features of bile acid diarrhea in patients with chronic diarrhea

OBJECTIVE

Bile acid diarrhea is a form of chronic diarrhea caused by excessive bile reaching the colon. Conditions involving the terminal ileum and cholecystectomy are predisposing factors but an idiopathic form of bile acid diarrhea has also been described. In this study we aimed to evaluate the prevalence of bile acid diarrhea in patients consecutively evaluated for chronic diarrhea in an Outpatient Gastroenterology Clinic.

METHODS

Medical records of all patients admitted for chronic diarrhea (>4 weeks) between June 2018 and April 2019 were retrospectively reviewed. Bile acid diarrhea was suspected in patients with ileal disease, cholecystectomy or post-prandial diarrhea. Patients' age at diagnosis, sex, presenting symptoms, results of main test and examinations, final diagnoses and date of last follow-up visit were also collected. Exclusion of chronic diarrhea of other causes and a 6-month clinical improvement with cholestyramine treatment confirmed the diagnosis of bile acid diarrhea.

RESULTS

In total, 139 patients aged 46 ± 20 years (76 women and 63 men) were included. Diarrhea due to an organic cause was diagnosed in 16 patients. A clinical response to cholestyramine persisting for more than 6 months led to a diagnosis of bile acid diarrhea in 39 (aged 52 ± 19 years) out of the remaining 123 patients with functional forms of diarrhea. Therefore, the prevalence of bile acid diarrhea was 28.1% (95% confidence interval 19.9%-38.4%) in patients with chronic diarrhea.

CONCLUSIONS

Bile acid diarrhea is a very common, yet under-recognized cause of chronic functional diarrhea. A therapeutic trial of cholestyramine is a valid diagnostic strategy.

Biochemical Diagnosis of Bile Acid Diarrhea: Prospective Comparison With the 75Seleno-Taurohomocholic Acid Test

INTRODUCTION

The diagnosis of bile acid diarrhea is often missed because the availability of the seleno-taurohomocholic acid (SeHCAT) test is limited. We aimed to compare the biomarkers 7α-hydroxy-4-cholesten-3-one (C4) and fibroblast growth factor 19 (FGF19) with the SeHCAT test.

METHODS

Patients with chronic diarrhea without intestinal resection referred for SeHCAT were prospectively recruited for this diagnostic accuracy study. Blood was sampled at fasting and after a stimulation meal with chenodeoxycholic acid. SeHCAT retention ≤10% defined bile acid diarrhea and >10% defined miscellaneous diarrhea. Receiver operating characteristics (ROC) were analyzed with SeHCAT as the gold standard. www.clinicaltrials.gov (NCT03059537).

RESULTS

Patients with bile acid diarrhea (n = 26) had mean C4 of 30 ng/mL (95% confidence interval: 19-46) vs 8 (7-11; P < 0.001) in the miscellaneous diarrhea group (n = 45). Area under the ROC curve (ROCAUC) for C4 was 0.83 (0.72-0.93). C4 < 15 ng/mL had 85% (74%-96%) negative predictive value; C4 > 48 ng/mL had 82% (59%-100%) positive predictive value. Twenty patients had C4 values 15-48 ng/mL, of whom 11/20 had SeHCAT ≤10%. Median fasting FGF19 was 72 pg/mL (interquartile range: 53-146) vs 119 (84-240) (P = 0.004); ROCAUC was 0.71 (0.58-0.83). Stimulated FGF19 responses did not differ (P = 0.54).

DISCUSSION

We identified C4 thresholds with clinically useful predictive values for the diagnosis of and screening for bile acid diarrhea in patients with chronic watery diarrhea. Further validation of the cutoff values with the placebo-controlled effect of sequestrant therapy is warranted (see Visual Abstract, Supplementary Digital Content 2, http://links.lww.com/AJG/B603).