Destructive Spondyloarthropathy with β ₂-Microglobulin Amyloid Deposits in a Uremic Patient before Chronic Hemodialysis

Abstract

We report a case of erosive arthropathies discovered radiologically before dialysis in a uremic patient with Alport syndrome. This patient had no hereditary amyloidosis or causes of acquired generalized amyloidosis (no chronic infections or inflammatory disease, neoplasia, lymphoma or monoclonal gammapathy). Erosive spondyloar-thropathies of the cervical spine at the C5-C6 and C6-C7 levels, erosive arthropathy of the right acromioclavicular joint, metacarpal lacuna of the right hand, and lacuna of the left femoral neck were discovered 24 months before starting dialysis in this patient with chronic renal insufficiency of 17 years duration. Puncture of the vertebral disc before starting dialysis took a fragment showing amyloid deposits with permanganate-sensitive Congo red staining and positive staining with anti-β₂-microglobulin antibodies. This observation suggests that β₂-microglobulin amyloidosis in uremia may not be exclusively related to chronic kidney replacement therapy, but to uremia per se, especially when the latter is of long duration.