Multifactorial analysis of biliary infection after percutaneous transhepatic biliary drainage treatment of malignant biliary obstruction

Background: The symptoms of patients with malignant biliary obstruction (MBO) could be effectively alleviated with percutaneous transhepatic biliary drainage (PTBD). Postoperative infections were considered as challenging issues for clinicians. In this study, the risk factors of biliary infection in patients after PTBD were analyzed. Methods: From July 2003 to September 2010, 694 patients with MBO received PTBD treatment. Bile specimens were also collected during PTBD. All relevant information and results were collected, including gender, age, obstruction time, types of primary tumor, sites of obstruction, drainage style, tumor stage, hemoglobin, phenotype of peripheral blood monocyte (Treg), total bilirubin, direct bilirubin, albumin, ChilduPugh score, and results of bile bacterial culture. Results: For the 694 patients involved in this study, 485 were male and 209 were female, with a mean age of 62 years (ranged 38u78 years). For the bile culture, 57.1% patients (396/649) were negative and 42.9% patients showed positive (298/694), and then 342 strains of microorganism were identified. The risk factors of biliary system infection after PTBD included: age (chi(2) = 4.621, P = 0.032), site of obstruction (chi(2) = 17.450, P < 0.001), drainage style (chi(2) = 14.452, P < 0.001), tumor stage (chi(2) = 4.741, P = 0.029), hemoglobin (chi(2) = 3.914, P = 0.048), ChilduPugh score (chi(2) = 5.491, P = 0.019), phenotype of peripheral blood monocyte (Treg) (chi(2) = 5.015, P = 0.025), and results of bile bacterial culture (chi(2) = 65.381, P < 0.001). Multivariate analysis suggested that high-risk factors were drainage style, ChilduPugh score, and results of bile culture. Conclusions: The risk factors of biliary infection after PTBD included: age, site of obstruction, drainage style, tumor stage, hemoglobin, ChilduPugh score, phenotype of peripheral blood monocyte (Treg), and results of bile culture. It was further concluded that drainage style, ChilduPugh score, and results of bile culture were independent risk factors.