Hidden crystals in the heart: A rare case of tophaceous aortic valve gout

We present the case of a patient with combined valvular heart disease and a history of gout. Following surgical replacement of the aortic and mitral valves, histopathological examination revealed extensive deposition of monosodium urate (MSU) crystals within the aortic valve leaflets. The lesion exhibited a central crystalline core, surrounded by a corona zone and fibrous vascular tissue. The nature of the urate crystals was confirmed using the classical, but rarely applied today - De Galantha’s staining technique. This method allows precise visualization of crystal deposits under light microscopy at various magnifications. No specific pathological findings were identified in the examined specimens from the mitral valve or in the thrombotic mass excised from the left atrium. Based on the histopathological findings, a definitive diagnosis of tophaceous involvement of the aortic valve was established.