Endoscopic retrograde cholangio-pancreatography (ERCP) is advanced endoscopic technique that allows minimally invasive management of biliary and pancreatic disorders. However, the incidence of infectious complication of ERCP is considerable. Transient blood stream infection after ERCP has been reported in a high ratio, up to 27% and post-ERCP infection accounts for about 10% of the major complications associated with mortality.

Although prophylactic use of antibiotics is generally not recommend in all cases, debates about the prophylactic use of antibiotics continues and prophylactic use of antibiotics is recommend in case of ERCP that incomplete biliary drainage is expected.

In this study, researchers will use prophylactic antibiotics in patients with biliary obstruction who have high-risk of post-ERCP bacteremia. Antibiotics regimen is selected based on the data of our institution, and administered to patients before ERCP procedure.

Inclusion Criteria:

• Patients with biliary obstructive disease (Benign or Malignant)
• 19 year-old and older than 19 year-old

Exclusion Criteria:

• Younger than 19 year-old
• Patients with leukocytosis (WBC ≥ 11,000/mm3)
• Body temperature ≥ 38 °C within 72 hours before ERCP
• History of antibiotics administration due to cholangitis, cholecystitis or sepsis within 72 hours before ERCP
• Pregnancy women
• Patients with allergy to beta-lactam