[This consensus document is intended to provide guidance for the effective and efficient treatment of asymptomatic individuals with high uric acid levels and gout patients.]

[The authors studied the solubility of urate crystals in alcohol, in an 8% aqueous solution of formaldehyde and in acetone, respectively. The urate crystals were least soluble in alcohol. In comparison, the amount of urate crystals decreased in the aqueous solution of formaldehyde, which confirmed the suggestion of our predecessors that tissues suspected to contain urate crystals should be fixed in alcohol. Urate crystals dissolved in greatest amounts in acetone. Acetone is widely used by histological laboratories for dehydration of tissue blocks before embedding them in paraffin, which, in case of fixation in aqueous formaldehyde, contributes to the dissolution of urate crystals. In our earlier studies, we found that dissolution of urate crystals from haematoxylineosin stained sections is caused by the staining of nuclei in haematoxylin, therefore urate crystals are preferably demonstrated in unstained tissue sections.]

[In medical practice there are a number of “truths etched in stone” that are passed on from textbook to textbook and learned by generations before they become obsolete. This short study aims to eliminate a misbelief from the diagnosis of gout that is related to the histological detectability of urate deposits. According to the generally accepted thesis, urate crystals obtained from patients with gout are dissolved in formalin solution, therefore, tissue samples should be fixated in alcohol. The authors have found that urate crystals can be detected on conventionally mounted, native (unstained) sections, despite formalin fixation, whereas the great majority of urate crystals are dissolved during haematoxylin-eosin staining. Therefore, for the detection of urate crystals the tissue samples should be examined on native, unstained sections.]

[In medical practice there are a number of “truths etched in stone” that are passed on from textbook to textbook and learned by generations before they become obsolete. This short study aims to eliminate a misbelief from the diagnosis of gout that is related to the histological detectability of urate deposits. According to the generally accepted thesis, urate crystals obtained from patients with gout are dissolved in formalin solution, therefore, tissue samples should be fixated in alcohol. The authors have found that urate crystals can be detected on conventionally mounted, native (unstained) sections, despite formalin fixation, whereas the great majority of urate crystals are dissolved during haematoxylin-eosin staining. Therefore, for the detection of urate crystals the tissue samples should be examined on native, unstained sections.]