Biomarkers for bile acid diarrhoea in functional bowel disorder with diarrhoea: a systematic review and meta-analysis.
There is no universally available laboratory test to diagnose bile acid diarrhoea (BAD).



To conduct a systematic review and meta-analysis to identify a biomarker for idiopathic BAD in patients with functional bowel disorder (FBD) with diarrhoea.



We searched multiple databases through 15 May 2015. Data were only available to estimate the diagnostic yield of each test (the prevalence of a positive test). Estimates were pooled across studies using the random effects model.



We included 36 studies, enrolling 5028 patients (24 using75selenium homotaurocholic acid test (75SeHCAT) retention of <10%, 6 using fasting serum C4, 3 using fasting serum fibroblast growth factor 19 (FGF19) and 2 based on total faecal bile acid (BA) excretion over 48 h). The diagnostic yields (and 95% CI) of abnormal tests were: 0.308 (0.247 to 0.377) for75SeHCAT retention (<10%), 0.171 (0.134 to 0.217) for serum C4, 0.248 (0.147 to 0.385) for serum FGF19 and 0.255 (0.071 to 0.606) for total faecal BA excretion over 48 h. The majority of the analyses were associated with substantial heterogeneity. Performance characteristics relative to a gold standard test could not be estimated.



Overall, the test with the highest diagnostic yield conducted in the largest number of studies was75SeHCAT retention, which is not widely available in many countries outside Europe and Canada. Using different diagnostic tests, 25% (average) of patients with lower FBD with diarrhoea has evidence of idiopathic BAD. These tests serve to identify idiopathic BAD among patients with FBD with diarrhoea. Further studies are required to appraise the performance characteristics of tests for idiopathic BAD.
Division of Gastroenterology, Department of Internal Medicine, Clinical Enteric Neuroscience Translational and Epidemiological Research (CENTER), Mayo Clinic, Rochester, Minnesota, USA.
Nelson
N
Valentin
Division of Gastroenterology, Department of Internal Medicine, Clinical Enteric Neuroscience Translational and Epidemiological Research (CENTER), Mayo Clinic, Rochester, Minnesota, USA.
Michael
M
Camilleri
Department of Internal Medicine, Allegheny General Hospital, Pittsburgh, Pennsylvania, USA.
Osama
O
Altayar
Division of Gastroenterology, Department of Internal Medicine, Clinical Enteric Neuroscience Translational and Epidemiological Research (CENTER), Mayo Clinic, Rochester, Minnesota, USA.
Priya
P
Vijayvargiya
Division of Gastroenterology, Department of Internal Medicine, Clinical Enteric Neuroscience Translational and Epidemiological Research (CENTER), Mayo Clinic, Rochester, Minnesota, USA.
Andres
A
Acosta
Division of Gastroenterology, Department of Internal Medicine, Clinical Enteric Neuroscience Translational and Epidemiological Research (CENTER), Mayo Clinic, Rochester, Minnesota, USA.
Alfred D
AD
Nelson
Division of Preventive Medicine, Department of Internal Medicine, Robert D and Patricia E Kern Center for the Science of Health Care Delivery, Mayo Clinic, Rochester, Minnesota, USA.
M Hassan
MH
Murad
D001647:Bile Acids and Salts / Q000378:metabolism*; D015415:Biomarkers / Q000378:metabolism; D002908:Chronic Disease; D003937:Diagnosis, Differential; D003967:Diarrhea / Q000175:diagnosis* / Q000209:etiology / Q000378:metabolism*; D019317:Evidence-Based Medicine; D006801:Humans; D043183:Irritable Bowel Syndrome / Q000150:complications / Q000175:diagnosis* / Q000378:metabolism*; D011237:Predictive Value of Tests; D012680:Sensitivity and Specificity
D001647:Bile Acids and Salts; D015415:Biomarkers
BILE ACID; DIARRHOEA; FUNCTIONAL BOWEL DISORDER; IRRITABLE BOWEL SYNDROME