Diagnosis of pseudogout and septic arthritis.

A patient with septic arthritis of the wrists was noted to have concurrent calcium pyrophosphate crystals in synovial fluid aspirated from both joints. These were present in unusually large numbers and were associated with destructive changes of the joints. It seemed likely that the complete dissolution of calcified cartilage accounted for the liberation of such numerous crystals. Previous reports of pseudogout associated with septic arthritis have noted the presence of abundant calcium pyrophosphate crystals in synovial fluid. It is suggested that this feature should always raise the possibility of concurrent sepsis.