The most appropriate management is endoscopic retrograde cholangiopancreatography (ERCP). The presence of fever, abdominal pain, and jaundice (Charcot triad) is consistent with acute cholangitis, and ERCP is indicated. Dilation of the extrahepatic and intrahepatic bile ducts on abdominal ultrasound or noncontrast CT scan is consistent with a diagnosis of choledocholithiasis, although dilated bile ducts may not be identified in patients with acute biliary obstruction. Acute cholangitis is usually caused by Escherichia coli, Klebsiella species, Pseudomonas species, and enterococci and can progress to septic shock with or without liver abscess formation. Empiric antibiotics targeting these likely organisms should be administered immediately when cholangitis is suspected. If improvement is not seen rapidly, urgent ERCP should be performed to remove the common bile duct stone. When duct decompression with ERCP is not possible, percutaneous cholangiography with biliary tube placement can be performed.

Abdominal CT is not appropriate because it would delay ERCP, which is needed urgently. In addition, it would not add much useful information to this patient's ultrasound findings.

Cholecystectomy will remove the source of future gallstones, but it will not decompress this patient's obstructed common bile duct or reduce her risk of dying from sepsis. Cholecystectomy will eventually be recommended for this patient; however, it must be delayed until the cholangitis is resolved.

Percutaneous cholecystostomy could be considered if this patient had acute cholecystitis, but her clinical history suggests common bile duct obstruction rather than simple cystic duct obstruction. The pain of acute cholecystitis typically lasts longer than 3 hours and shifts to the right upper quadrant, causing localized tenderness. The pain is due to gallbladder distention, ongoing gallbladder contraction against the obstructed outlet, and occasionally bacterial infection, leading to inflammation of the gallbladder wall. Fever, nausea, and vomiting are frequent findings, but jaundice is unusual. Findings of gallbladder inflammation may include thickening of the gallbladder wall (>2 mm), intramural gas, and pericholecystic fluid. These findings are not present in this patient.