Improving Empiric Antibiotic Therapy among Cancer Patients with Acute Cholangitis

Introduction: Acute cholangitis (AC) is a hepatobiliary infection that requires prompt antibiotic therapy. Providers have to rely on empiric antibiotic guidelines, before receiving culture results. These antibiotic guidelines require routine surveillance of the biliary microbial flora and resistance patterns found in cultures to increase accuracy and appropriateness of empiric therapy. This is particularly essential in cancer patients who are more likely to be exposed to various antibiotics, potentially creating unique bactobilia, and fungobilia selection pressures that are different from the general patient population and require empiric therapy to halt AC progression to septicemia, shock, or mortality. This unique population is poorly researched and primary literature is relatively scarce. Methodology: A retrospective chart review was performed to identify all patients between the age of 18 and 85 years who met the criteria for positive biliary culture and were treated for AC using empiric antibiotic treatment at the H. Lee Moffitt Cancer Center and Research Institute from January 2012 to January 2019. The patient information and laboratory results were analyzed to identify the microbial spectrum and drug resistance in bile cultures of cancer patients. Aim: The aim of the study is to review the microbial patterns and characteristics of AC in immunocompromised patients with cancer. Results: Pancreatic carcinomas and cholangiocarcinoma were most prevalent malignancies among patients. Although most bile cultures were polymicrobial, further analysis indicated Enterococcus species. Streptococcus species, Pseudomonas aeruginosa, Klebsiella pneumoniae, and Candida albicans were the most common isolates. Conclusions: Cholangitis in cancer patients develops because of cholestasis from cancer obstructing the biliary flow mostly because of pancreatic cancer, cholangiocarcinoma, and metastatic cancer to the porta hepatis. Empiric antibiotic therapy should include broad-spectrum coverage for usual enteric flora.