Department of Microbiology, St. Vincent's Hospital, Darlinghurst 2010, NSW, Australia.
Clin Microbiol Rev. 2009 Oct;22(4):634-50. doi: 10.1128/CMR.00017-09.
Globally, the number of immunosuppressed people increases each year, with the human immunodeficiency virus (HIV) pandemic continuing to spread unabated in many parts of the world. Immunosuppression may also occur in malnourished persons, patients undergoing chemotherapy for malignancy, and those receiving immunosuppressive therapy. Components of the immune system can be functionally or genetically abnormal as a result of acquired (e.g., caused by HIV infection, lymphoma, or high-dose steroids or other immunosuppressive medications) or congenital illnesses, with more than 120 congenital immunodeficiencies described to date that either affect humoral immunity or compromise T-cell function. All individuals affected by immunosuppression are at risk of infection by opportunistic parasites (such as the microsporidia) as well as those more commonly associated with gastrointestinal disease (such as Giardia). The outcome of infection by enteric protozoan parasites is dependent on absolute CD4(+) cell counts, with lower counts being associated with more severe disease, more atypical disease, and a greater risk of disseminated disease. This review summarizes our current state of knowledge on the significance of enteric parasitic protozoa as a cause of disease in immunosuppressed persons and also provides guidance on recent advances in diagnosis and therapy for the control of these important parasites.
在全球范围内，免疫抑制人群的数量逐年增加，人类免疫缺陷病毒 (HIV) 疫情在世界许多地区仍在继续蔓延。营养不良的人、接受恶性肿瘤化疗的患者以及接受免疫抑制治疗的患者也可能出现免疫抑制。免疫系统的组成部分可能因后天获得性疾病（例如 HIV 感染、淋巴瘤或大剂量类固醇或其他免疫抑制剂药物引起的疾病）或先天性疾病而出现功能或遗传异常，迄今为止已描述了超过 120 种先天性免疫缺陷，这些免疫缺陷要么影响体液免疫，要么损害 T 细胞功能。所有受到免疫抑制影响的人都有机会感染机会性寄生虫（如微孢子虫）以及与胃肠道疾病更相关的寄生虫（如贾第虫）。肠道原生动物寄生虫感染的结果取决于绝对 CD4(+) 细胞计数，较低的计数与更严重的疾病、更不典型的疾病以及更广泛疾病的风险相关。这篇综述总结了我们目前对肠道原生动物作为免疫抑制人群疾病病因的重要性的认识，还就这些重要寄生虫的诊断和治疗方面的最新进展提供了指导。
