禽類血色素沉著症之致病機制與感染關係之探討

Abstract

血色素沉著症 (Hemochromatosis) 是一種鐵代謝的異常導致鐵在人類和動物造成鐵過度的蓄積的常見疾病，又稱為鐵蓄積症 (Iron storage disease) 。在過去的三十年之間有越來越多的文獻指出；在圈養的鳥類有這一類疾病發生。所報告的鳥類的品種多以果實及昆蟲為主食，包括天堂鳥 (Paradiseadae) 、巨嘴鳥 (Ramphastidae) 、掠鳥 (Sturnidae) 及八哥 (Mynas) 等。在診斷上最常使用的是鐵染色 (Berlin blue) 以確認鐵在細胞內的堆積，這些受到損傷的細胞可能會因此而死亡且被纖維組織所取代。本研究中共收集186隻圈飼禽類解剖病例，其中有59隻 (31.7%) 以Berlin blue鐵染色確認罹患血色素沉著症，其中包括11個目，最常蓄積的組織以肝臟為主，依其嚴重程度分為三個等級 (Grade 1-3) ，嚴重者伴隨肝細胞壞死、肝索凌亂、肝細胞變性、膽管增生、Kupffer cell內有色素沉著、肝細胞內含有鐵質顆粒以及炎症反應的產生。此外，亦在心臟、腎臟及脾臟等器官出現。另外，針對於59例分析其飲食習慣、性別、年齡以及感染情況，分析結果顯示是否有患病與是否會感染間有著顯著之差異存在，證實患有血色素沉著症與感染之間有著交互關係存在。

Hemochromatosis is a common disorder of iron metabolism resulting in iron overload and affecting human and animals, particularly avian species. Genetic and dietary factors are considered as predisposing factors to cause hemochromatosis in these affected birds. Hemochromatosis has been diagnosed in 59 (31.7%) from 186 avian necropsies in this study and the affected species included 11 avian orders, and the most affected species is weaver bird. The organs most commonly affected are the liver. Histochemistry of iron stain (Berlin blue) is routinely used to confirm iron storage in the target tissues. Twenty-one out of 59 cases are hemochromatosis combined with infectious disease and 38 cases are hemochromatosis only. The statistic results show significant difference between the infections and hemochromatosis. In another test, no significant difference is analyzed among hemochromatosis with feeding behavior, age, and sex.