Amyloidosis¶

Overview¶

Amyloid deposition in the spine can cause destructive spondyloarthropathy, most commonly in patients on long-term hemodialysis (beta-2 microglobulin amyloidosis). It can also occur in systemic AL amyloidosis. The imaging findings mimic infection or tumor, making clinical context essential for diagnosis.

Imaging Findings¶

Disc space narrowing with endplate erosions
Vertebral body destruction
Perivertebral soft tissue mass
No significant inflammatory response (unlike infection)
May produce spinal stenosis from ligamentous and soft tissue deposition
Facet joint and ligamentum flavum thickening

Distinguishing Features¶

Clinical context: long-term hemodialysis patient
Normal inflammatory markers (unlike infection)
No disc T2 hyperintensity (unlike pyogenic spondylodiscitis)
Biopsy with Congo red staining confirms: apple-green birefringence under polarized light

Clinical Pearl

In a hemodialysis patient with destructive spondyloarthropathy and normal inflammatory markers, consider beta-2 microglobulin amyloidosis. The imaging can mimic infection, but the absence of fever, normal CRP/ESR, and dialysis history are key clues. CT-guided biopsy with Congo red staining confirms the diagnosis.

Key Points¶

Most common in long-term hemodialysis patients (beta-2 microglobulin)
Destructive spondyloarthropathy mimicking infection or tumor
Normal inflammatory markers help distinguish from infection
Congo red staining of biopsy tissue is diagnostic
Facet and ligamentum flavum thickening can cause spinal stenosis

References¶

Bustamante JG, Zaidi SRH. Amyloidosis. In: StatPearls. Treasure Island (FL): StatPearls Publishing; updated 2023 Jul 31. https://www.ncbi.nlm.nih.gov/books/NBK470285/
Connor T, Hole S. Musculoskeletal Amyloidosis Imaging. In: StatPearls. Treasure Island (FL): StatPearls Publishing; updated 2023 May 20. https://www.ncbi.nlm.nih.gov/books/NBK592389/
Theodorou DJ, Theodorou SJ, Resnick D. Imaging in dialysis spondyloarthropathy. Semin Dial. 2002;15(4):290-6. https://pubmed.ncbi.nlm.nih.gov/12191028/
Tsai TT, Kaliya-Perumal AK, Jenq CC, et al. The unresolved problem of beta-2 microglobulin amyloid deposits in the intervertebral discs of long-term dialysis patients. J Orthop Surg Res. 2017;12(1):194. https://pmc.ncbi.nlm.nih.gov/articles/PMC5740589/
Parmar H, Rath T, Castillo M, Gandhi D. Imaging of focal amyloid depositions in the head, neck, and spine: amyloidoma. AJNR Am J Neuroradiol. 2010;31(7):1165-70. https://www.ajnr.org/content/31/7/1165
Dialysis-related spondyloarthropathy. Radiopaedia.org. https://radiopaedia.org/articles/dialysis-related-spondyloarthropathy