Mineralizing pulmonary elastosis (MPE) is a rare and unique phenomenon that has been reported in humans, typically secondary to recurrent pulmonary haemorrhage. MPE has a complex histopathological appearance, often containing iron-calcium deposits that can be mistaken as fungal organisms or other inorganic material. This report documents the first case of MPE in an animal species. A 10-year-old female domestic cat with respiratory failure was submitted for necropsy. The lungs were consolidated with severe pulmonary haemosiderosis, and widely disseminated granulomas surrounded large aggregates of hyphae-like structures. The pulmonary vasculature and airway smooth muscle were partially mineralized and fragmented. Histochemical stains revealed that the fungus-like material stained strongly with Prussian blue and alizarin red but only sparingly with von Kossa and negative with Gomori's methenamine silver stain. These findings are similar to those of MPE in humans. As most veterinary pathologists may not be familiar with MPE, it is important to avoid possible misinterpretation by recognizing its distinct features and the ancillary testing that may be required.

矿化肺弹性组织变性 (MPE) 是一种罕见且独特的现象，已在人类中报道，通常继发于复发性肺出血。MPE 具有复杂的组织病理学外观，通常含有铁钙沉积物，可能被误认为是真菌生物或其他无机物质。该报告记录了动物物种中第一例 MPE。一只患有呼吸衰竭的 10 岁雌性家猫被送去尸检。肺部合并严重的肺含铁血黄素沉着症，广泛播散的肉芽肿包围大块菌丝状结构。肺血管系统和气道平滑肌被部分矿化和破碎。组织化学染色显示，真菌样物质被普鲁士蓝和茜素红强烈染色，但被 von Kossa 染色很少，被 Gomori 的甲胺胺银染色呈阴性。这些发现与人类 MPE 的发现相似。由于大多数兽医病理学家可能不熟悉 MPE，因此通过识别其独特的特征和可能需要的辅助测试来避免可能的误解很重要。