In the present study, we investigated the relationship between serum leukocyte cell-derived chemotaxin2 (LECT2) levels and liver function in patients with acute liver failure, and its use as a prognostic indicator. We studied six acute liver failure patients (two women, four men; 49.8 +/- 20.7 years old) admitted to our hospital in 2002. These patients had diagnoses of fulminant hepatitis due to acute liver failure (1) from congestive heart failure; (2) from portal venous gas, and (3) from postoperative disseminated intravascular coagulation (DIC). We measured serum LECT2, GOT, and GPT levels, the last two being inversely proportionate to the serum LECT2 levels. When the serum GPT levels peaked, the serum LECT2 levels were the lowest. When the liver function recovered, serum LECT2 levels increased. Three of four patients died due to liver failure, one to congestive heart failure. Maximum serum LECT2 levels among the expired group were significantly lower than those among the alive group (0.96 +/- 0.8 ng/mL vs 12.9 +/- 4.3 ng/mL). Serum LECT2 levels may be a prognostic indicator of recovery from liver failure. The present study suggests that in clinical medicine LECT2 participates in regeneration after injury of hepatocytes.