Plasma and urine levels of urinary trypsin inhibitor in patients with acute and fulminant hepatitis

Background and Aim Urinary trypsin inhibitor (UTI) is synthesized by hepatocytes and excreted into urine. Plasma and urine UTI levels have been measured to evaluate whether these levels may be useful markers in various pathological conditions. However, there has been no study on plasma and urine UTI levels in patients with acute liver diseases. The aim of the present study was to evaluate plasma and urine UTI levels and their relationship with the severity of hepatic damage in patients with acute liver diseases. Methods Plasma and urine UTI levels were measured by newly developed enzyme‐linked immunosorbent assay in 15 patients with acute hepatitis (AH), 12 patients with acute severe hepatitis (ASH) and 10 patients with fulminant hepatitis (FH), as assessed on admission. The serial changes in plasma and urine UTI were also observed in some patients with AH and ASH. Results Plasma UTI levels (U/mL, median [25–75th percentile]) were: 11.0, (9.5–16.1) in patients with AH; 7.8 (5.6–11.5) in those with ASH; 6.5 (4.0–9.5) in patients with FH; and 9.7 (7.3–11.0) in normal controls. Plasma UTI levels in patients with FH were significantly lower than in those with AH. Plasma UTI levels showed significant positive correlations with the levels of prothrombin time (PT), hepaplastin test, antithrombin III, α2‐plasmin inhibitor, plasminogen (Plg) and fibrinogen. After the recovery of liver dysfunction, increased plasma UTI levels in patients with AH were decreased, whereas previously decreased plasma UTI levels in patients with ASH were increased. Urine UTI levels were significantly increased in patients with AH compared with those of normal controls. In patients with ASH and FH, urine UTI levels were increased but not significantly. Urine UTI levels significantly positively correlated with PT and Plg. After the recovery of liver dysfunction, previously increased urine UTI levels in patients with AH were decreased. The correlation between plasma UTI and urine UTI levels was not significant. Conclusions The findings of the present study suggested that the levels of plasma and urine UTI changed in patients with AH and were closely related to the abnormalities of coagulo‐fibrinolysis, including PT. Further studies are needed to clarify whether these levels may be useful markers to predict the prognosis of acute hepatitis.