The development of fibrosis in patients with chronic hepatitis C infection can be assessed using liver biopsies.
However, the morbidity and potential mortality of liver biopsy means that a noninvasive method of assessing fibrosis is required.
Dr R Myers and colleagues at the University of Calgary, Canada, evaluated the use of historical features in predicting the progression of liver fibrosis.
106 patients, who had undergone liver biopsy, were categorized according to gender and age at infection; viral factors included the size of the inoculum, genotype and quasispecies; and extraneous factors, particularly alcohol consumption and coinfection with the human immunodeficiency virus or the hepatitis B virus.
The development of hepatic fibrosis in the time interval between the onset of hepatitis C infection in each patient and the date of liver biopsy was estimated using published rates of fibrosis progression.
The research team compared this estimate of fibrosis with the actual level of fibrosis found at liver biopsy.
Fibrosis was classified according to the Metavir system, with values ranging from F0 (no fibrosis) to F4 (cirrhosis).
For mild fibrosis (F0-F2) the positive predictive value of historical features was 78%, but for severe fibrosis (F3-F4) the positive predictive value was only 34%.
|Clinical history only had a positive predictive value of 34% for severe fibrosis|
|Journal of Viral Hepatitis|
Agreement between estimates of fibrosis and the histologically confirmed stage of fibrosis was low.
Dr Myers concludes, "The prediction of hepatic fibrosis using historical features is poor."
"Alternative noninvasive methods of predicting fibrosis are needed."