The ultrastructure of urate crystals in gout.

Using correlative scanning and transmission electron microscopic techniques, we studied the ultrastructure of natural and synthetic monosodium urate crystals. The internal architecture of both natural and synthetic urates consists of an interconnecting electron lucent network. This network is different in crystals from tophi, suggesting crystal formation about an electron lucent nidal matrix. Urate crystals from articular cartilage surfaces have smooth faces supporting the hypothesis that acute goat is a two phase process involving first the precipitation of urate crystals in the synovial fluid and second the adherence to the crystals of proteins and cells with the consequent inflammatory response.