Clinical Trial Details
— Status: Recruiting
Administrative data
| NCT number |
NCT05434949 |
| Other study ID # |
2022LAB126 |
| Secondary ID |
|
| Status |
Recruiting |
| Phase |
|
| First received |
|
| Last updated |
|
| Start date |
February 13, 2023 |
| Est. completion date |
February 2025 |
Study information
| Verified date |
January 2024 |
| Source |
The Royal Wolverhampton Hospitals NHS Trust |
| Contact |
R Gama |
| Phone |
01902307999 |
| Email |
rousseau.gama[@]nhs.net |
| Is FDA regulated |
No |
| Health authority |
|
| Study type |
Observational
|
Clinical Trial Summary
Chronic diarrhoea is common and often believed to result from irritable bowel syndrome (IBS).
However, up to 50% of patients with an IBS diagnosis may have something called Bile Acid
Diarrhoea (BAD) instead. BAD is easily treatable however diagnosis currently relies on a
complex test involving two full body scans. The aim of the study is therefore to investigate
whether a simple laboratory test, that can be done on a single blood sample, would be
appropriate instead. This laboratory test is called 7aC4.
In order to determine whether 7aC4 could be a good test for BAD, it needs to be determined
whether eating a meal can alter the levels of 7aC4. The aim of this study is to measure 7aC4
at several time points before and after eating a meal, to see what effect this has on 7aC4
levels.
Description:
Chronic diarrhoea is common and largely due to irritable bowel syndrome (IBS). IBS is
reported to affect about 11% of the UK population. About half these patients are believed,
however, to have bile acid diarrhoea (BAD). There are, therefore, more than one million
patients with BAD in the UK. BAD is caused by small bowel malabsorption of bile acids (BA)
and increased BA in the large intestine cause diarrhoea. Once diagnosed, the treatment of BAD
is simple and effective. BAD, however, is often not diagnosed because of a lack of easily
available and reliable diagnostic methods.
In the UK, the radiolabelled 23-seleno-25-homotaurocholic acid test (SeHCAT) is the
gold-standard diagnostic method. The SeHCAT is performed by oral administration of a
radiolabel, followed by two full-body scans, one week apart, to assess retention of BA. A low
retention time indicates BAD. SeHCAT, however, is expensive, inconvenient to the patient,
exposes the patient to radiation and has limited availability. A simple laboratory biomarker
for the diagnosis of BAD is, therefore, desirable.
Proposed diagnostic laboratory biomarkers for BAD include measurement of faecal BA and serum
7a-hydroxy-4-cholesten-3-one (C4). C4, an intermediate in the BA synthesis pathway, is the
common precursor for the primary BAs. It is, therefore, utilised as a biomarker of BA
synthesis. Serum C4 increases in BAD, as BA synthesis increases to compensate for the
increased faecal BA loss. C4 measurement requires a single serum sample for analysis by
liquid chromatography tandem mass spectrometry (LC-MS/MS). There is, however, limited data
comparing its diagnostic accuracy to the SeHCAT scan. Furthermore, pre-analytical variables
which may affect C4, include cholesterol lowering medication, diurnal variation and effects
of food intake require clarification to optimise conditions for sample collection before its
introduction into routine laboratory use. Literature suggests both diurnal variation and
post-prandial response can influence C4 levels, however there is limited information on
whether this is primarily a post-prandial response, or due to diurnal variation. This study
aims to compare pre- and post-prandial C4 levels, controlled for diurnal variation.
