Objective   To investigate the factors which influence nosocomial infection in the patients with malignant tumor of digestive tract.

  Methods   To collect all data from the medical records of patients with malignant tumor of digestive tractin one integr ated hospital during 2001.Analyze the affecting factors with logistic regression base on 1:2 match case control study.

  Results   Simple factor conditional logistic regression analysis showed that nosocomial infection was significantly as sociated with accumulate course of disease; hospitalization with infection; the period in hospital accumulate days; application antibiotic before infection; grade of nursing; objective of application antibiotic et al; 22 risk factors(P < 0.05).Multiple factor conditional logistic regression analysis revealed that application antibiotic before infection(OR 3.55, OR 95% CI=1.09~11.60, P=0.036), the length of hospitalization over 28 days(OR 5.92, OR 95% CI=2.08~16.91, P=0.001), type of surgery wound(OR 4.84, OR 95% CI=1.01~23.40, P=0.042), complications after operation(OR 17.35, OR 95% CI=5.37~55.47, P=0.000)were all significantly independent risk factors for nosocomial infection.

  Conclusion   Occur rence of the nosocomial infection in the patients with malignant tumor of digestive tract correlated to the application antibiotic before infection, length of hospitalization over 28 days, type of surgery wound and complications after operation.