There are two types of steato-sis, defined by the size of these agebeen shown that only patients with biopsy-confirmed NASH willand gender- matched general population . However, it has(4) Why QUANTIFYfatty liver disease? developcirrhosis, liver failure and hepatocellular carcinoma .(8) intra-cytoplasmic fat deposits: macrovesicular steatosis, which As the clinical symptoms and signs of fatty liver diseases are is the most common, generally generally minimal –or even non-existent – the condition is The term non-alcoholic fatty liver disease covers a broad spectrumHistology grades the proportion of hepatocytes containing lipid vacuo- benign form, and the rarer, often often diagnosed via laboratory tests (elevated aminotransfe- of forms, degrees of severity and prognoses. These range fromles on a three to five point scale. This is a rather rough quantification serious form called microvesicu- rase values) or by its accidental discovery during an x-ray or non-progressive (non-alcoholic) fatty liver disease to progressivewhich only shows the proportion of affected hepatocytes but does not ultrasoundexamination(1, 8). Recent studies have concluded that (non-alcoholic) steatohepatitis which causes inflammation of the provideany information on the actual quantity of liver triglycerides .(3) lar steatosis. The two main causes of fatty liver disease are excessive alcohol consumption and obesity, but the condition is also asso-fatty liver disease and insulin-resistance could play a pivotal roleliver and which may subsequently lead to fibrosis and cirrhosis. TheFurthermore, it is impossible to distinguish between NASH and alcoholic inthe physiopathology of type 2 diabetes . By contrast, the(9) physician must therefore be able to identify patients with the pro-steatohepatitis (ASH) on the basis of histological findings, and alcohol ciated with other diseases such as diabetes, insulin resistance and hyperlipidemia. When combined, these conditions are collectivelymechanisms triggering progression from asymptomatic fattygressive form with a view to offering them regular monitoring and, abusecan only be ruled out by questioning the patient .(11) liver disease to steatohepatitisare still poorly understood . With(3) wherepossible, treatment . It is impossible to distinguish between(11) Ultrasound and CT will detect extensive steatosis, i.e. affecting more knownas metabolic syndrome (1-3), which can be diagnosed on the basis of both clinical and biological criteria. Fatty liver can also bedietary habits changing not just in the Western world but alsothe two on the basis of their clinical presentation and, until now,than 30% on histological grading, but a more refined quantification caused by malnutrition, use of certain medicinal products or as ain the emerging countries, the problem has global connotationstheir diagnosis using non-invasive methods (for instance, x-rays oris impossible. MRI is the only reliable means of quantifying fatty liver complication of surgery. Non- alcoholic fatty liver disease (NAFLD)and its serious consequences and the lack of viable therapeuticultrasound examinations) has not been feasible. At the present time,disease, but this examination tends to be used mainly in clinical trials is one of the primary reasons for seeking the services of a liver spe- alternativesmean that it is also a major public health concern .(2)histology is considered to be the reference method for the diagnosisand studies rather than in routine daily practice. In France, MRI is not cialist(4,5). «Pure», non-progressive steatosis is diagnosed if there isGrowing awareness of the major role played by fatty liver disease offatty liver . However, a liver biopsy is an invasive examination(5) yet ubiquitously available, and its cost prohibits its use as a means no inflammation, necrosis or fibrosis in the l iver. Liver inflammationas a risk factor for chronic liver damage is coupled with the needand its use in routine clinical practice for the diagnosis of what isof measuring fatty liver in routine clinical practice(3). None of these is a sign of non- alcoholic steatohepatitis (NASH) which can lead tofor a better understanding of the underlying physiopathological essentiallyan indolent disorder is questionable .(3)imaging methods (ultrasound, CT or MRI) measures the degree of l iver hepatic fibrosis and cirrhosis(5) mechanisms. Simple, effective diagnostic tools are urgently Histology is not an accurate means of measuring liver steatosis.inflammation or fibrosis(1) . . required. One such solution would be to set up clinical trials to test new and targeted treatmentmethods .(10) Epidemiological data The past few years have seen a considerable rise in the prevalenceof fatty liver disease in the general population, in both Western Interview with Prof. Victor de Ledinghen countries(5)and Asia(6, 7). This disease affects all races and all age Head of the Hepatogastroenterology and Gastrointestinal groups(4). In the USA, the estimated prevalence in the general Oncology Department at the Haut-Levêque hospital, population is 3 to 24%, with the condition affecting one third of the Bordeaux Pessac University Hospital adult population and 10% of children and teenagers(2, 4, 8). The incidence is also high in France, with 10 to 20% of the adult popu- Why bother quantifying prolonging the examination time. New software lation affected. The prevalence of fatty liver fatty liver disease? allows calculation of the extent of steatosis (by Fatty liver disease is a condition caused by themeasuring attenuation of the ultrasound signal) disease in the general population in Japan presence of excessive fat in the liver. In itself,at the same time as fibrosis (measuring theexaminations for patients with hepatitis C. is 14% and obesity is the most common co- it is not dangerous. However, patients withspeed with which a shock wave crosses the liverIf the examination is done for reasons unrelated factor(6). In China, the disease affects almost fatty liver disease run the risk of subsequentlytissue), using either the M or the XL probe placedto hepatitis C, it is therefore not reimbursed. It 21%of the adult population . It is more(7) developing inflammatory damage which mayon the skin, over the liver and perpendicular tois important to continue to develop its uses in common in men and its incidence rises with in turn cause fibrosis, cirrhosis and cancer. Thisthe skin. The procedure can be done either byother indications, such as diabetes, hypertension is known as metabolic steato pathy and is mainlya trained physician or by trained nursing staff.and obesity, so that the CNAM can reimburse age. In women, the incidence of fatty liver seen in diabetic and obese patients. It is theAs is the case for other imaging techniques, theexaminations performed in these other patient diseaserises steeply after menopause(2, 6, 7) results are interpreted by a doctor. groups. The examination costs almost 30 times . first stage of a disease that may later become It is very common in patients who have had serious. In medicine, the earlier a disease is less than a liver biopsy. Each of the geographical bariatric surgery (between 84 and 96%. diagnosed, the better it can be treated. If weWhat are the advantagesdepartments in France has at least one traditional can measure the steatosis, we will be able toover a biopsy? Fibroscan; some centres also have the equip- Twenty-five to 55% of these patients present with steatohepatitis, diagnose a potentially life- threatening condi-A biopsy is not to be taken lightly. It is anment required to measure both fibrosis and 34 to 17% with fibrosis and 2 to 12% with a combination of fibrosis tion at a very early stage. Fatty liver disease isinvasive examination that brings with it a highsteatosis. In the future, its use could be extended andcirrhosis . In the United States, the prevalence of liver biopsy-(2) also an aggravating factor in hepatitis C and arisk of complications, the main one beingto other diseases, such as alcohol dependency confirmedsteato hepatitis is about 3 to 5% . For patients with pure(8) risk factor for complications in patients under-haemorrhaging which can be fatal. A biopsywhich is the leading cause of liver damage in going a liver transplant. Once the diagnosis hascannot be repeated regularly, every three toFrance. As steatosis decreases with abstinence, steatosis, the prognosis is good and there is no risk of a negative six months for instance. It can’t even be donethis examination could be a valuable means outcome. Conversely, patients with steatohepatitis are liable to been reached and treatment started, measuring steatosis can also be a means of assessing treat-on an annual basis, and this makes it difficultof monitoring patients and their willingness to developfibrosis and even cirrhosis . The disease is potentially(5) ment efficacy. If there is less fatty liver, then theto monitor treatment efficacy. In addition, astop drinking. progressivein ten to 40% of patients . The severity of liver damage(1) treatment can be considered to be effective. Ifliver biopsy only evaluates about 1/50 thou- is known to increase with age and in patients with a high body mass this is not the case, then the treatment will have sandthof the liver, whilst the Fibroscan probe®What do you feel is most important evaluates1/500 of the liver, i.e. 100 timesth about CAP and its development? index (BMI), diabetes, hypertension, elevated triglycerides and/or to be modified. more liver tissue. In theory, the non-invasiveIt is important to point out that, before CAP insulin-resistance(2, 6, 7) Can you describe a Fibroscan®Fibroscan examination is therefore 100 times® was launched, the only way to diagnose stea- . examination? more representative than a liver biopsy. Moretosis was through conventional ultrasound. Major public health concern TheFibroscan provides a totally non-i nvasive,® reliable and risk-free, the examination can beQuantification was not possible at all. A liver user-friendly and painless means of measuringrepeated as often as needed.ultrasound will show that steatosis is present hepatic fibrosis. The Fibroscan uses Vibration only if it represents more than 30% of the liver Patients with fatty liver disease and concomitant obesity and Controlled Transient Elastography(VCTE) atTMHow is it currently being used andtissue. CAP is currently the only non-invasive diabetes have a 15 to 20% risk of developing NASH, which may 50 Hz to measure liver stiffness. A new method,are the examinations reimbursedexamination that genuinely quantifies steatosis. inturn develop into cirrhosis and cancer(2, 3). Insulin resistance Controlled Attenuation Parameter (CAPTM), hasby the national insurance systemIt is much more precise, which is very important and oxidative stress play an important role in the onset and beencoupled with the Fibroscan making it® in France? in terms of diagnosis and prognosis for patients. progressionof NAFLD . Morbidity and mortality are higher in(4) possible to measure – and above all quantifyAt the present time, the Caisse Nationale d’Assu- - hepatic steatosis for the very first time. Both pa-rance Maladie (CNAM) [France’s national health patients with non-alcoholic steatohepatitis who go on to present rameters are measured simultaneously; withoutinsurance body] only reimburses Fibroscan® with fibrosis and cirrhosis. Patients with NASH and these hepatic complications are significantly more at risk of death than the