Clinical significance of erosive azotemic osteodystrophy: a prospective masked study

To determine the relationship between joint symptoms and radiographically identifiable erosions in patients on maintenance hemodialysis for 4 or more years.

A prospective study was carried out on 21 patients, who underwent rheumatological evaluation and radiographic surveys of all clinically examined joints. The radiologist was masked to the clinical information and the clinicians were masked to the radiographic findings. Cuprophane dialyzers were used on all patients. The statistical analysis was performed by unpaired t-test and Fisher's exact test.

Ten men and 11 women comprised the 21 patients, of whom 10 had joint symptoms and clinical signs whereas 11 did not. Age, gender, and duration of hemodialysis did not differ significantly between the symptomatic and asymptomatic group. Of the 21 patients, 10 had radiological evidence of erosions and 11 did not. The average age of patients with erosions was 64.9 years; this was significantly different from the age of the group without erosions, which was 54.1 years. The group with radiographic evidence of erosions had been on dialysis for an average of 9.6 years, while those without erosions had received dialysis for an average of 6.4 years. Of the 11 patients without radiographic evidence of erosions, three were symptomatic. Of the 10 patients with erosions, seven had musculoskeletal symptoms, but only in four was there concordance between radiological findings and symptoms of the corresponding joints. The positive predictive value of radiographic erosions in predicting clinically significant disease was 40%. There was poor correlation between the presence of radiographic erosions and clinical signs and symptoms of joint disease.