Dialysis-related beta 2 microglobulin-amyloid arthropathy. Improvement of clinical symptoms after a switch of dialysis membranes.

Amyloidosis containing beta 2 microglobulin (beta 2m) and joint pains are frequent complications of long-term hemodialysis. In a prospective study the authors planned to act on dialysis arthropathies (DA) by improving beta 2m depuration: for 8 patients suffering from DA we replaced usual cuprophane membranes (CU) by high permeability polyacrylonitrile membranes (PAN). DA was diagnosed on the presence of severe disabling arthralgias in the absence of any other obvious etiology, and on the presence of at least 3 among 6 criteria. The efficacy of the switch of DM was assessed on 6 criteria including the patient's own evaluation at the end of the study and a joint pain severity index. Clinical evaluation and beta 2m measurement were carried out at the start of the trial and after a mean duration of dialysis on PAN of 6 months. An improvement in joint symptomatology and a decrease of joint severity index were noted in the 8 cases. Our results suggest that the change of DM has a favorable influence on DA. This improvement could result either from a better beta 2m depuration or from a better biocompatibility of PAN than the CU previously used.