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When rheumatologists extracted synovial fluid of joints with a special microscope (polarised light) they look for the existence of microcrystals. Their detection allows for the diagnosis of gout regardless of the levels of uric acid in the blood.
Moreover, during attacks of gout, some patients may have normal uric acid and would not be diagnosed correctly if only the levels of uric acid in blood are taken into account. Therefore it is important to remove the fluid for examination.
There is no association between consumption of tomatoes and uric acid, therefore any patient with gout may consume them if desired.
