Seeto R K, Rockey D C
Department of Medicine, University of California, San Francisco, USA.
West J Med. 1999 Feb;170(2):104-9.
Amebic liver abscess (ALA) is a serious, but readily treatable form of hepatic infection. In order to understand the clinical features of this condition in the United States, we reviewed the medical histories of 56 patients with ALA at two large San Francisco Hospitals from 1979 to 1994. Patients were divided into the following groups based on the presumed manner in which they had acquired ALA: those born or raised in the United States, with a history of travel to an endemic area (Tr-ALA); those from an endemic area, but living in the United States for less than one year (En-ALA); and those neither from nor having traveled to an endemic area (N-ALA). We found distinct clinical patterns in patients from different epidemiological groups. Patients with Tr-ALA were a decade older than those from endemic regions, were more likely to be male, and tended to have an insidious onset. Furthermore, compared to patients with En-ALA, those with Tr-ALA were more likely to have hepatomegaly (P < 0.0001) and large abscesses (ALA > 10 cm; P < 0.01). One third of the patients studied had no associated travel history or endemic origin as risk factors. Of these, 63% had a condition consistent with severe immunosuppression, such as infection with the human immunodeficiency virus (HIV), malnourishment with severe hypoalbuminemia, or chronic infection. In patients with N-ALA, the presence of a presumed immunosuppressed state increased significantly, as compared to patients with endemic or travel risk factors for ALA. During the last five years of the study, one third of all patients diagnosed with ALA were HIV positive (including 2 with a new diagnosis of AIDS), many of whom were discovered to be HIV-infected only after presentation with ALA. We conclude that travel to and origin in an endemic area are important risk factors for the development of ALA, and patients in these different epidemiological groups appear to have distinct clinical features. Further, in the absence of recognized risk factors, the development of ALA may suggest an immunocompromised host.
阿米巴肝脓肿（ALA）是一种严重但易于治疗的肝脏感染形式。为了解美国这种疾病的临床特征，我们回顾了1979年至1994年旧金山两家大型医院56例ALA患者的病史。根据推测的ALA感染方式，患者被分为以下几组：在美国出生或长大且有前往流行地区旅行史的患者（Tr-ALA）；来自流行地区但在美国居住不到一年的患者（En-ALA）；以及既非来自流行地区也没有前往流行地区旅行史的患者（N-ALA）。我们发现不同流行病学组的患者有不同的临床模式。Tr-ALA患者比来自流行地区的患者大十岁，男性比例更高，发病往往较隐匿。此外，与En-ALA患者相比，Tr-ALA患者更易出现肝肿大（P<0.0001）和大脓肿（ALA>10 cm；P<0.01）。三分之一的研究患者没有相关旅行史或流行地区来源作为危险因素。其中，63%的患者有一种与严重免疫抑制相符的情况，如感染人类免疫缺陷病毒（HIV）、伴有严重低白蛋白血症的营养不良或慢性感染。与有ALA流行或旅行危险因素的患者相比，N-ALA患者中推测的免疫抑制状态的存在显著增加。在研究的最后五年中，所有诊断为ALA的患者中有三分之一是HIV阳性（包括2例新诊断为艾滋病的患者），其中许多患者在出现ALA后才被发现感染了HIV。我们得出结论，前往流行地区旅行和来自流行地区是ALA发生的重要危险因素，这些不同流行病学组的患者似乎有不同的临床特征。此外，在没有公认危险因素的情况下，ALA的发生可能提示宿主免疫功能低下。
