Dialysis-related amyloidosis in a large CAPD population

We studied 212 patients from 13 Italian dialysis centers to evaluate the clinical aspects of dialysis-related amyloidosis in continuous ambulatory peritoneal dialysis (CAPD). The mean age was 64.2 +/- 12.3 years and mean time on dialysis was 36.9 +/- 25.1 months. Residual diuresis was 615.7 +/- 554.0 mL/day and plasma beta 2-microglobulin (beta 2M) level was 27.0 +/- 12.8 mg/L. Radiological skeletal examination, neurological problems related to beta 2M, and urinary and dialytic balance of beta 2M were evaluated. Correlations between age, time on dialysis, residual diuresis, beta 2M plasma levels, beta 2M peritoneal and renal removal, carpal tunnel syndrome, and bone disease were studied. Only the number of bone lesions had a significant positive correlation with patient age and negative correlation with residual diuresis. The latter had an inverse relation with beta 2M plasma levels. Dialytic age did not correlate with any of the parameters. No other correlation was observed. Hand lesions were found in 85% of patients with bone dialysis-related amyloidosis. In conclusion, residual diuresis in our patients played a positive role in the number of bone localizations. Only age, but not time on dialysis, had a positive impact on the bone lesions. The high percentage of hand lesions suggests that the observation of this skeletal segment is a simple, safe, and effective modality of bone follow-up for dialysis-related amyloidosis.