RESUMO
Joint problems have been retrospectively analyzed in 10 uremic patients (mean age, 61.9 years; range, 50-70) undergoing long-term hemodialysis treatment for more than 10 years. All the patients suffered from arthralgias which were mainly localized in the shoulder region (9 patients). The arthralgias began 2-9 years after the initiation of intermittent hemodialysis. Eight out of the 10 patients had the carpal tunnel syndrome. Only three patients had evidence of marked secondary hyperparathyroidism but nine had aluminum intoxication. Juxta-articular calcium deposits were observed in 8 patients one of whom had pseudo-tumoral calcifications made of hydroxyapatite crystals. These soft tissue calcium deposits occurred 1-8 years after starting hemodialysis. Conspicuous X-ray abnormalities were found in 8 patients: destructive arthropathy in 5 cases, arthropathies of large joints in 5 cases consisting of sub-chondral lacunae and joint space narrowing or even disappearance. Prosthetic joint replacement was required in 4 patients: replacement of the hip in 3 and of the knee in 1. Massive amyloid deposits could be demonstrated in removed joints of 3 patients and in carpal tunnel of the 7 patients operated upon. They were located in the synovium, articular capsula and juxta-articular epiphyseal bone. It is probable that this is a new type of amyloidosis made of beta 2-microglobulin. The underlying pathogenetic mechanisms of these arthropathies remain to be defined by further studies.
