- White-red nodules, most commonly on the digits and auricles and overlying joints
- Secondary to hyperuricemia
- Dermal and subcutaneous deposits of amorphous gray, white or weakly eosinophilic material (tophi) surrounded by palisading granulomas
- If the tissue is alcohol fixed or there is incomplete formalin fixation, the uric acid crystals are visible with polarization as doubly-refractive (yellow when parallel to the condensator and blue when perpendicular to it), needle-shaped crystals.
- The tophi stain positive with von Kossa or, more specifically, de Galantha stains.