Review for 10.1186/1471-230X-10-40 (2010)

Reviewer's report
Title:Prevalence of liver fibrosis and risk factors in a general population using
non-invasive biomarkers (FibroTest)
Version: 1Date:8 March 2010
Reviewer: Jerome Guechot
Reviewer's report:
In this pilot study Poynard and col. have evaluated the feasibility of using
Fibrotest® (a serum multivariate test developed by some of these authors) as a
non invasive marker for the screening of liver fibrosis in the general population
and used it to estimate the prevalence of liver fibrosis.
Transient elastography with Fibroscan® (a device using ultrasound to measure
liver stiffness) was used as a confirmation test.
This study is timely and important considering that treatments of fibrosing liver
diseases are possible and since it can be speculated that liver fibrosis could be
easily diagnosed with the non invasive methods recently described.
In fact, there are different questions posed in the paper: 1/ Is the Fibrotest® valid
for a fibrosis screening? 2/ When assessed by FT, what is the prevalence of liver
fibrosis in the general population? 3/ What could be the best strategy to used in a
large population screening of liver fibrosis?
Discretionary Revisions
The methods are well described. However exclusion criteria have to be
developed since 33 patients were excluded because of non interpretable FT.
This number is small when compared to the number of included subjects but is
not negligible compared to the 209 subjects with presumed fibrosis.
Consumption of liver toxic drugs can be a cause of liver fibrosis. However no
data about drugs consumption was given.
The characteristics of the screened population are largely described and
compared to the characteristics of the French population. Information about the
prevalences of Gilbert’s syndrome, hemolysis, and acute inflammation have to be
considered since these situations have a risk of false positive or false negative
FT. Furthermore the high risk profile of false FT (0.4%) is not negligible
compared with the observed fibrosis prevalence (2.8%).
When the patients with presumed fibrosis were reinvestigated they had a second
FT, the concordance between the two FT could be more detailed.
In this study the observed prevalence of cirrhosis was 0.3%, however the authors
does not discuss if it is effectively the prevalence in the French population over
40 years of age?
The authors show that there were only one third of subjects with liver fibrosis who
had ALT greater than 50 IU/L. In ALT oriented strategy, the choice of this cutoff is
not discussed and is surprising since the upper normal values were 26 IU/L in
women and 35 IU/L in men, and the “viral hepatitis oriented strategy” is defined in
methods with an ALT level above normal.
The observation that the use of CDT might be used as marker of alcohol
consumption instead of self-reported alcohol consumption is not only original as
claimed by the author but also unexpected. So this point might be more
discussed: Were the self-reported alcohol consumptions well completed using a
validated method? What about the use of GGT or MCV?
In the discussion, the authors discard other “non-patented” fibrosis biomarkers
because “the diagnostic performance of FT is superior”. However they have not
been evaluated in general population. So, some data using APRI (or others
simple and low-cost biomarkers) compared with FT might be interesting in the
studied population.
Level of interest: An article of importance in its field
Quality of written English: Acceptable
Statistical review: Yes, but I do not feel adequately qualified to assess the
statistics.
Declaration of competing interests:
I declare that I have no competing interests