By Dr. Charles Shepherd
There is a very good review of the illness known as primary biliary cirrhosis (PBC) in a recent edition [July 2003] of The Lancet medical journal.
As PBC has a number of important similarities to ME/CFS, and occasionally gets misdiagnosed as ME/CFS, I will run through some key points:
1. The two most common symptoms of PBC are chronic fatigue and itching of the skin (pruritis). Despite PBC being a potentially serious liver disease, jaundice is unusual and only tends to occur once it has become severe.
2. PBC tends to affect middle aged females.
3. Although the cause is unknown, genetic factors and immune system dysregulation are involved. There is also evidence of hormonal dysfunction, in particular impaired corticotropin-releasing hormone activity (as in ME/CFS).
4. Suspicions about a diagnosis of PBC should be raised in anyone who has chronic fatigue and abnormal liver function tests (as can obviously occur in ME/CFS) – especially if there is a rise in the level of a liver chemical called alkaline phosphatase (2-10 times upper limit of normal). Modestly raised levels of liver enzymes also occur.
5. Evidence of immune system dysfunction comes from the presence of autoantibodies (again as can happen in ME/CFS), especially antimitochondrial antibodies (titres greater than 1/40). And an autoimmune rheumatic disorder called Sjogren's syndrome is more common in people with PBC (as it is with ME/CFS).
6. The fatigue part of PBC is particularly interesting in that it has similar qualities to that seen in ME/CFS, and in the case of PBC it has been shown to be independent of the severity of the liver disease, sleep disturbance or depression (further similarities with ME/CFS).
So it seems that PBC fatigue may be related to abnormalities in brain chemical transmitters (possibly good old serotonin) and it's interesting to note that one small study (ref: Lancet, 1999, 354, 397) has shown that a drug called ondansetron/Zofran can significantly reduce PBC fatigue. There is also a report from Germany suggesting that this drug could be of benefit in ME/CFS (ref: Scandinavian Journal of Rheumatology, 2000, 29, suppl 113, 72-77).
7. Making a correct diagnosis of PBC as early as possible is important because effective treatment with a drug called ursodeoxycholic acid will halt the progression of the disease and reduce the need for a possible liver transplant later on.
Source: 'Primary biliary cirrhosis', Lancet, 2003, 362, 53 – 61.
More information on PBC and ME/CFS can be found in Dr. Charles Shepherd's book, "Living with ME" on page 96. To purchase this book from amazon.com, click on the following link: http://www.amazon.com/exec/obidos/tg/detail/-/0091816793/qid=1057691914/sr=1-1/ref=sr_1_1/104-2012199-1654354?v=glance&s=books