A comparison of the fibrotic potential of nonalcoholic fatty liver disease and chronic hepatitis C

In nonalcoholic fatty liver disease the amount of fibrosis for individual histologic stages is unknown. To better understand the fibrotic potential of nonalcoholic fatty liver disease, we compared the amount of fibrosis in nonalcoholic fatty liver disease versus chronic hepatitis C virus patients. The area of fibrosis for equivalent fibrosis stages was measured by micromorphometry in 70 nonalcoholic fatty liver disease and 70 matched, untreated, chronic hepatitis C virus controls. The area of fibrosis correlated with Brunt stage (r = 0.71; P < .001) in nonalcoholic fatty liver disease and METAVIR stage (r = 0.58; P < .001) in chronic hepatitis C virus. Mean area of fibrosis was similar in nonalcoholic fatty liver disease and chronic hepatitis C virus patients (7.77% versus 7.70%). Although chronic hepatitis C virus patients displayed higher area of fibrosis in early disease (no or mild fibrosis), nonalcoholic fatty liver disease and chronic hepatitis C virus patients had similar area of fibrosis in more advanced disease (7.83% versus 8.06%, respectively; P = .86 for bridging fibrosis; and 16.62% versus 12.98%, respectively; P = .29 for cirrhosis). The area of fibrosis was similar in Brunt stage 3 nonalcoholic fatty liver disease and METAVIR stage 2 chronic hepatitis C virus, the usual threshold for initiating therapy. The area of steatosis declined with increasing fibrosis stages confirming the early loss of liver fat with progressive fibrosis in nonalcoholic fatty liver disease. Fibrosis is as abundant in nonalcoholic fatty liver disease as in chronic hepatitis C virus, especially in the advanced stages of the disease. The fibrotic potential of nonalcoholic fatty liver disease is as severe as that of chronic hepatitis C virus.