Abstract：
Immunocompromised patients account for an increasing proportion of the typical intensive care unit (ICU) case-mix. Because of the increased availability of new drugs for cancer and auto-immune diseases, and improvement in the care of the most severely immunocompromised ICU patients (including those with hematologic malignancies), critically ill immunocompromised patients form a highly heterogeneous patient population. Furthermore, a large number of ICU patients with no apparent immunosuppression also harbor underlying conditions altering their immune response, or develop ICU-acquired immune deficiencies as a result of sepsis, trauma or major surgery. While infections are associated with significant morbidity and mortality in immunocompromised critically ill patients, little specific data are available on the incidence, microbiology, management and outcomes of ICU-acquired infections in this population. As a result, immunocompromised patients are usually excluded from trials and guidelines on the management of ICU-acquired infections. The most common ICU-acquired infections in immunocompromised patients are ventilator-associated lower respiratory tract infections (which include ventilator-associated pneumonia and tracheobronchitis) and bloodstream infections. Recently, several large observational studies have shed light on some of the epidemiological specificities of these infections-as well as on the dynamics of colonization and infection with multidrug-resistant bacteria-in these patients, and these will be discussed in this review. Immunocompromised patients are also at higher risk than non-immunocompromised hosts of fungal and viral infections, and the diagnostic and therapeutic management of these infections will be covered. Finally, we will suggest some important areas of future investigation.
摘要：
免疫功能低下的患者在典型的重症监护病房（ICU）病例组合中所占的比例越来越高。由于癌症和自身免疫性疾病的新药越来越多，和改善最严重的免疫功能低下的ICU患者（包括恶性血液病患者）的护理，重症免疫功能低下患者形成高度异质性的患者群体。此外，大量没有明显免疫抑制的ICU患者也有潜在的疾病改变他们的免疫反应，或因脓毒症而导致ICU获得性免疫缺陷，外伤或大手术。虽然在免疫功能低下的危重患者中，感染与显著的发病率和死亡率相关，关于发病率的具体数据很少，微生物学,该人群ICU获得性感染的管理和结局。因此,免疫功能低下的患者通常被排除在ICU获得性感染治疗的试验和指南之外.免疫功能低下患者中最常见的ICU获得性感染是呼吸机相关的下呼吸道感染（包括呼吸机相关性肺炎和气管支气管炎）和血流感染。最近,几项大型观察性研究揭示了这些感染的一些流行病学特异性，以及这些患者多重耐药细菌的定植和感染动态，这些将在本次审查中讨论。免疫功能低下的患者比非免疫功能低下的宿主有更高的真菌和病毒感染风险，这些感染的诊断和治疗管理将获得承保。最后,我们将提出一些未来调查的重要领域。
