Gallbladder adenomyomatosis presenting as fever of unknown origin: a case report

Gallbladder adenomyomatosis is a rare disorder, characterized by benign hyperplasia of the gallbladder mucosa creating invaginations through the muscular layer, known as Rokitansky-Aschoff sinuses. It is considered an acquired disease, with pathophysiology similar to that of the diverticular disease of the colon. Diagnosis is often achieved by ultrasound, but a significant percentage is misdiagnosed as chronic cholecystitis, whereas the diagnosis is finally achieved histologically. We describe a case of gallbladder adenomyomatosis presenting as fever of unknown origin. The patient was a 17-year-old girl with a history of sustained fever of 38.5 degrees C of two months' duration. There were no accompanying symptoms and the whole diagnostic workup, including abdominal ultrasound, was negative. Gallbladder inflammation was evident during an eventual investigatory laparoscopy, and cholecystectomy was performed. The histologic results were consistent with diffuse adenomyomatosis. The patient became afebrile immediately after cholecystectomy. To our knowledge, fever has never been associated with gallbladder adenomyomatosis before in bibliography, nor has adenomyomatosis been mentioned as a cause of fever of unknown origin. We therefore believe that gallbladder adenomyomatosis should be considered in the differential diagnosis of sustained fever with negative workup.