Evaluation of destructive spondyloarthropathies in hemodialysis by computerized tomographic scan and magnetic resonance imaging

Objective. The incidence of destructive spondyloarthropathies (SA) in hemodialysis can reach 50% after 10 years of treatment. Few studies have analyzed the magnetic resonance (MR) appearance of destructive SpA and data are controversial. Our objective was to evaluate the computerized tomographic (CT) scan and MR appearance of destructive SpA in comparison to infectious spondylodiscitis. Methods. 23 destructive SpA were observed in 11 patients who had undergone hemodialysis [mean duration of treatment 12 years (89-228 mo)]: 17 SpA of the cervical spine, one of the dorsal, and 5 of the lumbar spine. CT scans at all levels demonstrating narrowing and discovertebral erosions were performed without injection. MRI was performed with T1 and T2* weighted spin echo sequences (0.5 T) without gadolinium injection. Radiographs were analyzed by 2 independent examiners. The data concerning MRI of infectious spondylodiscitis were based on a study of 57 personal cases and literature reports. Results, CT scan appearance was similar in all cases, especially showing multiple small well defined lucencies of the vertebral endplates. In 9 patients, MRI showed low signal intensity of the disk and the adjacent vertebral endplates on T1 and T2* sequences. In no case was discal or vertebral high signal intensity on T2* sequence noted. No periodontoidal pseudotumor was observed. Conclusion. CT scans and MRI of destructive SpA, even nonspecific, are different from those observed in infectious spondylodiscitis, particularly due to the absence of discal and vertebral hyper-signal on T2* sequences.