Ascending Cholangitis Caused by Methicillin-Resistant Staphylococcus aureus Species in a Patient With Cystic Fibrosis

Ascending cholangitis is a bacterial infection of the extra-hepatic biliary system and presents as a life-threatening systemic condition. Increased bacterial loads and biliary obstruction favor bacterial translocation into the vascular and lymphatic systems. Common organisms isolated are Escherichia Coli, Klebsiella, Enterococcus species, and Enterobacter species. Methicillin-resistant Staphylococcus aureus (MRSA) is a rare isolate in ascending cholangitis. We present a case of a 24-year-old patient with cystic fibrosis who presented with epigastric abdominal pain, low-grade fever, jaundice, dark urine, and nausea for two days. Initial workup revealed elevated liver enzymes, hyperbilirubinemia, leukocytosis, and an ultrasound which showed common bile duct dilation to 14 mm with choledocholithiasis. He underwent endoscopic retrograde cholangiopancreatography (ERCP) with stone extraction and bile fluid culture. Cultures grew out MRSA and the patient was treated with appropriate antibiotic therapy. The mainstay of therapy for ascending cholangitis is adequate hydration, antibiotics, and biliary decompression. Early recognition of the offending organism is critical in guiding therapy. Current guidelines focus on the empiric treatment of Gram-negative and anaerobic bacteria. Clinicians should be aware of the possibility of less common pathogens (such as MRSA), especially in a patient who is decompensating despite antibiotic therapy.