Acute pseudogout in chronic renal failure.

Acute pseudogout (calcium pyrophosphate dihydrate deposition disease [CPPD disease]) developed in two patients with chronic renal failure. The disease had atypical features. The calcification of the involved joints was more diffuse than the usual linear stippled calcification. The first patient, age 39, was young to have pseudogout. The second patient had pseudogout and chondrocalcinosis limited to the elbow. Review of wrist roentgenograms of 82 patients (mean age, 49.0 years), undergoing hemodialysis for chronic renal failure revealed three patients (a 3.7% incidence) with chondrocalcinosis. The incidence increased to three of 19 (15.8%) in the patients over the age of 60. Although considered uncommon, pseudogout may cause acute arthritis in chronic renal failure more often than previously suspected. Joint aspiration and identification of CPPD cystals with compensated polarized light microscopy will establish the diagnosis of pseudogout.