Currently, the most reliable method of judging how damaged the liver has become, due to either hepatitis B, hepatitis C, or drug-induced liver injury, is a liver biopsy. This is the process of extracting a tiny sample of the liver via a needle through the skin, for the purpose of laboratory examination.

Spurred on by patients who are increasingly resisting this unpleasant procedure, some members of the medical community now believe that liver biopsies are unnecessarily invasive, and that there are less traumatic alternatives.

The most promising of these is ultrasound elastography, a French invention with the trade name, FibroScan. It is a risk- and pain-free examination with an instantaneous result: an ultrasound probe is simply held against the skin where it detects the degree of stiffness in liver tissue in a process that lasts under than ten minutes.

A recent French study^[1] found that it was efficient in detecting serious liver damage in patients coinfected with HIV and hepatitis C. However another study, in HIV-negative patients with hepatitis C, found that FibroScan alone wasn't as effective in determining light-to-moderate liver damage, and suggested that FibroScan in combination with a non-invasive blood test known as FibroTest would give the most reliable results^[2].

Since it is a new invention, and has not yet undergone rigourous scrutiny by the National Health Service, the machine, which costs around £40,000, is not yet routinely available in the United Kingdom, although it is already being used in some hospitals in France, Italy and Israel.

However, ATU has learned that a FibroScan machine is about to debut at one London hospital, and it is hoped that another will appear at a second London site very soon. We asked Dr Mark Nelson from Chelsea & Westminster Hospital, and Dr Sanjay Bhagani, from the Royal Free Hospital to explain the pros and cons of FibroScan, and who might benefit from it.

Why do we need alternatives to liver biopsies?

Sanjay Bhagani [SB]: Liver biopsies are the 'gold standard' for assessing liver damage but they're not without their problems. It's an invasive, uncomfortable procedure with some, albeit very minimal, risks. There are also substantial costs associated with them – not only in terms of discomfort and risks for the patient, but also in terms of use of hospital beds. There is also an error rate associated with liver biopsies due to variations in the way liver biopsies can be interpreted.

Mark Nelson [MN]: Although there is a risk of – sometimes serious - bleeding afterwards, for the majority of people it's safe, if little uncomfortable, and usually not as bad as the patient expects. I should stress, however, that it is something that people don't want, and would prefer not to have, so it's good to try and look for alternatives.

How did the Royal Free Hospital acquire its FibroScan machine?

SB: Over the last year or so we've become increasingly aware of the need to try and offer the best we can for our patients. Currently, there aren't enough data regarding the use of FibroScan in HIV/hepatitis C coinfected patients, and there are even fewer data on the use of FibroScan in patients coinfected with hepatitis B. So we have acquired our machine for research use through an unrestricted educational grant from Gilead Sciences [who produce several drugs for hepatitis B, and are developing oral drugs for hepatitis C].

What's the situation at the Chelsea & Westminster?

MN: We've talked to some of the people who already use FibroScan in France and Italy and they tell us it's revolutionised patient care in their clinics. Consequently, I think it's something that we need. So, St Stephen's AIDS Trust [an HIV/AIDS charity based at the Chelsea & Westminster] is almost certainly going to buy a FibroScan machine. Why is an HIV charity paying for it rather than the NHS? The problem is that although there are some small studies showing that it appears to work very well, NHS guidelines and protocols mean they won't pay for it right now. Hopefully the studies that are done here and at the Royal Free will help pave the way for NHS acceptance.

Who will benefit from the machine right now?

SB: To begin with, only patients taking part in research. We plan to compare FibroScan against liver biopsies in patients coinfected with HIV and hepatitis C, and in particular, hepatitis B. Perhaps the most useful thing we'll  be able to do with FibroScan is to follow coinfected patients more closely – perhaps at half-yearly or annual intervals – rather than at the three-year interval currently recommended with liver biopsies. Data presented at the Retrovirus conference last year³ showed that about 25% of patients coinfected with HIV and hepatitis C progressed faster than expected over those three years, and we want see if we can use the FibroScan to identify the people who are progressing more rapidly.

MN: Whilst there are many questions about how to best use the machine – and we don't have one yet – I feel as a trustee of the St Stephen's AIDS Trust that the charity is there to help all people living with HIV, and not just to help a group of patients who attend the Chelsea & Westminster.

Is this the beginning of the end for liver biopsies?

MN: We all want FibroScan to work, but we have to be aware that anything can be wrong – including liver biopsies. However, I'm hoping that this may overcome a major hurdle in managing liver disease.

SB: I don't think that FibroScan could completely replace liver biopsies. There are some things that only a liver biopsy can tell you: FibroScan can't tell you how much inflammation there is in the liver or what's causing the liver damage, or how much steatosis (fatty liver) there is. We still need to work out how best to utilise FibroScan, but I suspect it may be most useful in monitoring patients more frequently, as well as monitoring response to treatment.

References

1. De Lédinghen V et al. Diagnosis of hepatic fibrosis and cirrhosis by transient elastography in HIV/hepatitis C virus-coinfected patients. JAIDS 41: 175-179, 2006.

2. Castera L et al. Prospective comparison of transient elastography, Fibrotest, APRI, and liver biopsy for the assessment of fibrosis in chronic hepatitis C. Gastroenterology 128(2): 343-350, 2005.

3. Sulkowski M et al. Unexpected significant liver disease among HIV/HCV-co-infected persons with minimal fibrosis on initial liver biopsy. Twelveth Conference on Retroviruses and Opportunistic Infections, Boston, abstract 121, 2005.