Isolated Hepatic Actinomycosis Mimicking Cholangiocarcinoma: A Case Report and Literature Review

原發性肝放射菌病似為膽管癌：病例報告及文獻回顧

許富傑(Fu-Chieh Hsu) ； 蘇子誠(Tzu-Cheng Su) ； 楊良友(Albert D. Yang) ； 廖瓊瓔(Chiung-Ying Liao) ； 李國維(Kwo-Whei Lee)

《Journal of Radiological Science》 37卷1期 (2012/03) Pp. 29-33+55

https://doi.org/10.6698/JRS.201203_3701.05

摘要

原發性肝放射菌病是罕見、可用腫塊型態表現的感染性疾病。我們報告一例病理證實為肝放射菌病極少病例。超音波及電腦斷層呈現單一巨大腫塊。在核磁共振影像表現上似為周邊型膽管癌，T1加權影像呈現低訊號，T2加權影像呈現高訊號，且伴隨邊緣的顯影。在彌散加權成像（DW-MRI）所測得平均水分子擴散係數值（apparent diffusion coefficient）卻明顯低於過去文獻中周邊型肝內膽管所表現之值。原發性肝放射線菌病特徵為常延伸至腹壁，腫塊內有眾多蜂窩狀中隔，通常對於抗生素反應良好，但易誤診為腫瘤。為避免延誤治療即不必要肝切除，熟悉這些影像學特徵是必需的。

並列摘要

Isolated hepatic actinomycosis (IHA) is a rare infectious disease, which presents as a space-occupying lesion. We present a case of pathologically proven liver actinomycosis. Ultrasonography and computed tomography scan revealed a large solitary liver mass. The mild heterogeneously enhancing mass appeared as a hypointense area on a T1-weighted image and as a hyperintense area on a T2-weighted image, with a peripherally enhancing rim, and mimicked the appearance of a peripheral cholangiocarcinoma (PCC) on magnetic resonance imaging (MRI). However, the mean apparent diffusion coefficient (ADC) value (0.78 × 10^(-3) s/mm^2) of the mass obtained from diffusion-weighted MRI (DW-MRI) was significantly lower than that of PCCs. IHA is characterized by extension of the mass to the abdominal wall and the presence of numerous honeycomb-like septa within the mass. IHA generally responds well to antibiotic therapy but is easily misdiagnosed. Knowledge of the radiological features of IHA is essential for avoiding delayed treatment and unnecessary surgery.