ACUTE GOUTY SYNOVITIS ASSOCIATED WITH URATE MILK

Objective. To analyze the clinical features of acute gouty synovitis a ssociated with thick, milky white, ''chalky,'' urate laden synovial ef fusions, and to investigate the effects on synovial white blood cell ( WBC) counts when leukocyte-rich rheumatoid effusions are incubated wit h a urate packed milky synovial fluid. Methods. Five patients (all men , mean age 70.8 years) with acute gouty synovitis (acute arthritis in 3, acute bursitis in 2) associated with ''urate milk'' were studied be tween 1993 and 1996. Results. Synovial effusions were thick, ''chalky, '' and appeared ''milky'' white. The fluids were packed with monosodiu m urate (MSU) crystals, which sedimented upon standing, leaving a clea r supernatant containing a few MSU crystals. The presence of massive a mounts of MSU crystals and crystal clumps interfered with accurate det ermination of synovial WBC counts. Four fluids showed ''a few leukocyt es,'' and one a WBC count of 6750/mm(3) with 91% neutrophils and sever al intraleukocytic crystals. Four patients had subcutaneous tophi. Of the risk factors associated with development of gout, the most frequen t was ethanol abuse, in 4 and possibly all 5 patients. Incubation of l eukocyte-rich rheumatoid synovial effusions with urate laden knee flui d from Patient 5 produced a greater reduction in synovial WBC counts c ompared to controls. Conclusion. Milky white synovial effusions contai ning massive quantities of urate crystals (referred to as ''urate milk '') may rarely occur in the setting of acute gouty arthritis or bursit is. Ethanol abuse appears to be a risk factor associated with the deve lopment of hyperuricemia and gout in these patients.