Analysis of Clinical, Imaging, and Pathological Features of Osseous Echinococcosis

Abstract Objective To investigate the clinical, imaging, and pathological features of osseous cystic echinococcosis(CE) and osseous alveolar echinococcosis(AE) to enhance diagnostic accuracy and differential diagnosis capabilities. Methods A retrospective analysis of 58 pathologically confirmed osseous echinococcosis cases was conducted, collecting demographic, clinical, imaging, and histopathological data. Results Of 58 patients, 49 (84.48%) had osseous CE and 9 (15.52%) had osseous AE. Both types predominantly affected farmers/herdsmen. The spine was the most commonly affected site (CE: 70.41%, AE:44.44%), and multi-site involvement was common (CE: 71.43%, AE: 88.89%). Osseous CE showed multilocular cystic hypodense lesions (57.97%) on CT and "grape-cluster-like" lesions with long T1/T2 signals (90.16%), with ring-like enhancement of the cyst wall and septa sometimes on MRI. Osseous AE presented heterogeneous density with calcifications(50%) on CT, and MRI showed mixed signals, with calcifications and fibrous components showing low signals on T2WI. Histopathologically, osseous CE specimens contained "laminated membrane"–like material (68.35%); powder-stained plate-like stratum corneum was observed under the microscope (100%). Osseous AE displayed necrotic debris (70.00%); honeycomb-like microcysts were seen within the necrotic background (100%). Conclusion Osseous CE and AE share overlapping Clinical features, but exhibit differences in CT/MRI and pathological characteristics. Compared to osseous CE, osseous AE demonstrated broader site distribution, more frequent multisystem involvement, and a more aggressive clinical course with shorter disease duration prior to diagnosis. Mastering the key features is essential for accurate diagnosis.