Recurrent cholangitis associated with biliary sludge and Phrygian cap anomaly diagnosed by magnetic resonance imaging and magnetic resonance cholangiopancreatography despite normal ultrasound and computed tomography.

A 31-year-old woman presented with a one and half years' history of intermittent right upper quadrant (RUQ) pain, high fever and severely painful, warm and reddish swollen skin lesions on the fingers. Acute attack resolution occurred within 2 weeks after treatment with non-specific antibiotics. Low-grade fever (around 37.5 degrees C) and less painful swellings continued for 6 months after each attack. Abdominal ultrasound and computed tomography (CT) scans did not show any abnormality during the attacks. Biopsy of the skin lesions after the second attack revealed lymphocytic vasculitis. All laboratory studies including rheumatologic serology panel were normal. One month after the complete resolution of the second attack, the patient was observed to have high fever, the same skin lesions on the fingers as at the initial stage, nausea and marked abdominal pain in the RUQ. Routine laboratory studies including complete blood count, liver function tests and serum amylase and lipase levels were normal. An abdominal CT scan revealed a slight thickening of the gallbladder wall (3.9 mm). Two weeks later, abdominal magnetic resonance imaging (MRI) and magnetic resonance cholangiopancreatography (MRCP) were performed because of persistent abdominal pain. They revealed both biliary tract and pancreatic gland alterations consistent with past cholangitis and pancreatitis with coexisting Phrygian cap anomaly and biliary sludge on the neck of the gallbladder.