Of all the symptoms one may have, itching is one of the most difficult to understand and even harder to define. Basically, itching is any sensation that causes urge to scratch.
Itching, like other symptoms, can have many different causes.
Some of these we understand such as the itching caused by the release of histamines that irritate nerve endings.
This happens when you get an insect bite or come in contact with some substance such as poison ivy or oak.
People with liver diseases may also experience itching that is caused by the deposit of bile products in the skin when the liver is damaged and cannot function properly to remove them.
There is however, no association between the amount of bile products deposited and the amount of itching that one may experience.
Link: http://www.hepcaustralia.com.au/index.php?option=com_content&task=view&id=124&Itemid=47
I just came across your question. I am hoping that in the five years since you posted that you have an answer. But I will let you know what I have found out. I have Hep C and have suffered with the itching for many years, mostly when I took birth control pills and during both of my pregnancies. I just recently starting investigating this itch myself, because like you my doctors are not that informed about itching. I came across the diagnosis of Cholestasis. It is described as an intense itching caused by liver disease, especially Hep B & C. The great thing is that there is a drug called Cholestyramine that is used to treat the itch. There is also surgery and Endoscopy available to help relieve the itching. As for me, I will try the drug over surgery and Endoscopy. I hope that this helps not only you but others out there who are suffering.