Virtual autopsy investigation of gallstones in an 18th century Sicilian mummy

Gallstones represent a relatively rare finding in ancient human remains, and they are almost always related to high social classes. We report gallbladder stone disease detected by computed tomography-guided virtual autopsy in an 18th century natural mummy found in the Church of Sant’Anna in Modica, southeastern Sicily. The mummified body was conservatively investigated by external examination and computed tomography (CT) scanning. 3D rendering and virtual autopsy approach enabled us to recognize multiple stones in the gallbladder, whereas densitometry allowed us to reconstruct the exact stone morphology and establish the chemical composition. The mummy belonged to an anonymous plump elder man with poor dental status, calcified lung nodules, pelvic phleboliths, and severe osteoarthritis of the spine and the right hip. Seven gallstones measuring 1.3 to 2.0 cm in largest diameter were observed. They had ellipsoid shape and inhomogeneous morphology with central hypodense cores and density values ranging from 70 to -289 Hounsfield Units (average: -40). These features suggested combined cholesterol gallstones. Gallstones may be easily recognized in natural mummies through a CT-guided virtopsy approach, whereas densitometry may help to establish their chemical composition. In the present case, cholesterol-based stones were probably due to dietary factors and genetic predisposition like their modern counterparts. Along with the other pathological findings (obesity, phleboliths, dental status) gallbladder stones represent a good bioanthropological marker of high social class.