AIM: To investigate the correlation between the changes of pancreatic enzyme, the biochemical markers and the clinical results according to the Balthazar computer tomography (CT) grade. METHODS: Between July 2004 and July 2005, we reviewed the charts of 119 patients who were admitted to our hospital with acute pancreatitis. RESULTS: Eighty-three patients (69.7%) were male, and the mean age of the patients was 57 ± 15.7 years. The biliary pancreatitis patients had an older mean age. Forty-nine patients (41.1%) had biliary pancreatitis and forty-six (38.6%) had alcoholic pancreatitis. Group 3 patients had a longer duration of pain (2.51 ± 1.16 vs 3.17 ± 1.30 vs 6.56 ± 6.13, P < 0.001), a longer period of fasting (7.49 ± 4.65 vs 10.65 ± 5.54 vs 21.88 ± 13.81, P < 0.001) and a longer hospital stay (9.17 ± 5.34 vs 14.63 ± 8.65 vs 24.47 ± 15.52, P < 0.001) than the other groups. On the univariate analysis, the factors that affected the radiological grade were the leukocyte count at admission (P = 0.048), the hemoglobin (P = 0.016) and total bilirubin concentrations (P = 0.023), serum lipase (P = 0.009), the APACH Ⅱ scores at admission (P = 0.017), the APACH Ⅱ scores after 24 h (P = 0.031), the C-reactive protein (CRP) titer (P = 0.0001) and the follow up CRP titer (P = 0.003). But the CRP level (P = 0.001) and follow up CRP titer (P = 0.004) were only correlated with the radiological grade on multivariate analysis. According to the ROC curve, when we set the CRP cut off value at 83 mg/L, the likelihoodratio for a positive test was 3.84 and the likelihood ratio for a negative test was 0.26 in group 3. CONCLUSION: In conclusion, our study suggests that the CRP with the radiological severity may be used to estimate the severity of acute pancreatitis. A to investigate the correlation between the changes of pancreatic enzyme, the biochemical markers and the clinical results according to the Balthazar computer tomography (CT) grade. METHODS: Between July 2004 and July 2005, we reviewed the charts of 119 patients who were admitted to our hospital with acute pancreatitis. RESULTS: Eighty-three patients (69.7%) were male, and the mean age of the patients was 57 ± 15.7 years. The biliary pancreatitis patients had an older mean age. Forty-nine patients (41.1% Group 3 patients had a longer duration of pain (2.51 ± 1.16 vs 3.17 ± 1.30 vs 6.56 ± 6.13, P <0.001), a longer period of fasting (7.49 ± 4.65 vs 10.65 ± 5.54 vs 21.88 ± 13.81, P <0.001) and a longer hospital stay (9.17 ± 5.34 vs 14.63 ± 8.65 vs 24.47 ± 15.52, P <0.001) than the other groups. On the univariate analysis, the factors that affected the radiological grade were the leukocyte count at The APACH II scores at admission (P = 0.017), the hemoglobin (P = 0.016) and total bilirubin concentrations (P = 0.023), serum lipase The C-reactive protein (CRP) titer (P = 0.0001) and the follow up CRP titer (P = 0.003). But the CRP level (P = 0.001) and follow up CRP titer (P = 0.004) were only correlated with the radiological grade on multivariate analysis. When to set the CRP cut off value at 83 mg / L, the likelihoodratio for a positive test was 3.84 and the likelihood ratio for a negative test was 0.26 in group 3. CONCLUSION: In conclusion, our study suggests that the CRP with the radiological severity may be used to estimate the severity of acute pancreatitis.