Calcium pyrophosphate dihydrate deposition disease of the filum terminale.

Abstract

Calcium pyrophosphate dihydrate crystal deposition disease (CPPDD) is a rare benign inflammatory joint disorder characterized by the presence of calcium pyrophosphate dihydrate crystal in the interarticular and periarticular tissue. It has been rarely described with spinal localization. A 50-year-old woman, affected by CPPDD, presented a progressive weakness of both lower limbs associated with neurogenic claudication. Neuroradiological examinations revealed the presence of two intradural calcified lesions at level L3-L4, with no post-contrast enhancement. Surgery was performed and the histopathological exams documented the presence of rod-shaped crystals embedded in a fibrocartilaginous stroma. The postoperative course was uneventful and the patient experienced complete symptoms relief with a 5-year follow-up. Intradural CPPD localization at the filum terminale is an extremely rare occurrence. Total removal should be preferably attempted with a long-term focal control of the disease as we observed in our case.