Dialysis-related amyloidosis.

end-stage failure patients which has been recognized a Amyloid arthropathy decade ago. It generally occurs after several years of The deposition of b2M amyloid clearly is associated renal replacement therapy [1,2]. However, it may be with the syndrome of chronic arthralgias and arthropaseen occasionally in patients with long-standing, severe thy in dialysis patients, although the precise pathogenrenal failure who are not yet treated by dialysis or etic role played by amyloid deposits still needs to be related procedures [3,4]. It is mainly localized in osteoclarified. Its incidence augments with increasing time articular structures. It is often associated with the on dialysis and with ageing [10]. The condition has occurrence of the carpal tunnel syndrome and painful, been described mainly in patients dialysed with the chronic arthropathies that may evolve to progressive cuprophane membrane but the use of synthetic, highly joint destruction. permeable dialysis membrane offers no absolute longIn 1985, two groups of workers showed that term protection. It would appear that once the amylb2-microglobulin (b2M) was the major constituent oidogenetic process has started it is difficult, if not protein of dialysis-associated amyloidosis [5,6 ], even impossible, to stop it completely, even by changing the though a number of other proteins have been found dialysis procedure. since in the amyloid deposits as well, including serumThe chronic arthralgias are usually bilateral and derived amyloid P component (SAP), glycosaminooften involve the shoulders initially. Other joints, in glycans, proteases, antiproteases, ubiquitin, and particular the knees, wrists and small joints of the immunoglobulin light chains [7,8]. The b2M protein hands, may be involved as well. Chronic joint swelling accumulates in the plasma of chronically uraemic is another important feature of the disease, as may be patients, and this accumulation is almost certainly a recurrent hemarthrosis and chronic tenosynovitides of major contributing factor in the formation and tissue the finger flexors. deposition of b2M amyloid and associated pathological Destructive arthropathies of large peripheral joints conditions. However, several other factors appear to and of the spine may ensue, causing major incapacity. play an important role as well which are discussed Massive amyloid deposits are almost constantly below. observed at the site of such lesions [11,12]. They are