From skin to microscope, case report of a rare manifestation of tophaceous gout: Miliary gout.

Joint symptoms associated with gout, mostly characterized by joint flare-ups, are well known. Tophi represent the main cutaneous manifestation of gout, most often associated with a chronic and inadequately controlled disease. On rare occasions, atypical skin manifestations may occur. We present the case of a miliary form of gout in a 36-year-old man known to have hyperuricemia. Microscopic direct analysis of the skin material revealed the presence of monosodium urate (MSU) crystals. Rash disappeared with corticosteroid therapy in parallel with joint symptoms recovery. Knowledge of this unusual gout-related skin disease is essential to diagnosing uncommon presentations of gout, which sometimes occur before joint symptoms. This case highlights the importance of sampling any skin lesion suspected of being tophus, for MSU crystal identification, and provides a definitive diagnosis.