From the Department of Radiology, Chonnam National University Hwasun Hospital, Chonnam National University Medical School, Jeollanam-do, Republic of Korea (S.H.H., J.W.K., H.S.L., H.J.S., Y.Y.J., H.K.K.); and the Departments of Radiology (S.S.S.) and Internal Medicine (S.I.J.) and the Center for Aging and Geriatrics (S.S.S.), Chonnam National University Hospital, Chonnam National University Medical School, 8 Hack-dong, Dong-gu, Gwang-ju 501-757, Republic of Korea.
Radiographics. 2014 Jan-Feb;34(1):19-33. doi: 10.1148/rg.341135077.
Actinomycosis is a chronic suppurative bacterial infection caused by Actinomyces species. Actinomyces israelii is the organism most commonly found in human disease. Actinomycosis usually manifests with abscess formation, dense fibrosis, and draining sinuses. The disease is further characterized by the tendency to extensively spread beyond normal fascial and connective tissue planes. Actinomycosis occurs most commonly in the cervicofacial region (50%-65%), followed by the thoracic (15%-30%) and abdominopelvic (20%) regions, but rarely involves the central nervous system. Most cases of cervicofacial actinomycosis are odontogenic in origin. In the acute form, cervicofacial disease can manifest with soft-tissue swelling, a painful pyogenic abscess, or a mass lesion. In the subacute to chronic form, a painless indurated mass can spread to the skin, leading to draining sinus tracts. Thoracic manifestations include parenchymal, bronchiectatic, and endobronchial actinomycosis. At computed tomography, pulmonary actinomycosis usually appears as chronic segmental airspace consolidation containing necrotic low-attenuation areas with peripheral enhancement. Abdominopelvic actinomycosis preferentially involves the ileocecal region, ovary, and fallopian tube. The imaging findings favoring abdominopelvic actinomycosis include strong enhancement in the solid portion of the mass after contrast material administration, small rim-enhancing abscesses within the mass, and extensive inflammatory extensions. Actinomycosis in the central nervous system may produce brain abscess, meningitis, subdural empyema, actinomycetoma, and spinal and cranial epidural abscess. In general, actinomycosis responds well to antibiotic therapy, but long-term follow-up after treatment is needed because of frequent relapses.
放线菌病是一种由放线菌属引起的慢性化脓性细菌感染。以色列放线菌是人类疾病中最常见的病原体。放线菌病通常表现为脓肿形成、致密纤维化和窦道引流。该疾病的特征还在于广泛扩散至正常筋膜和结缔组织平面之外的趋势。放线菌病最常发生于颈面部（50%-65%），其次是胸部（15%-30%）和腹盆腔（20%），但很少涉及中枢神经系统。大多数颈面部放线菌病源于牙源性。在急性形式中，颈面部疾病可能表现为软组织肿胀、化脓性脓肿疼痛或肿块病变。在亚急性到慢性形式中，无痛性硬结肿块可扩散至皮肤，导致窦道引流。胸部表现包括实质、支气管扩张和支气管内放线菌病。在计算机断层扫描（CT）上，肺部放线菌病通常表现为慢性节段性气腔实变，包含坏死性低衰减区域和周围强化。腹盆腔放线菌病优先累及回盲部、卵巢和输卵管。支持腹盆腔放线菌病的影像学表现包括：对比剂给药后肿块实性部分的强烈强化、肿块内小边缘强化脓肿和广泛的炎症延伸。中枢神经系统放线菌病可导致脑脓肿、脑膜炎、硬膜下积脓、放线菌肿和脊髓颅外硬膜外脓肿。一般来说，放线菌病对抗生素治疗反应良好，但由于频繁复发，需要在治疗后进行长期随访。
