Vargas Edwin, Apewokin Senu, Madan Rajat
Division of Infectious Diseases, Department of Internal Medicine, University of Cincinnati, 231 Albert Sabin Way, MSB 6109, ML 0560, Cincinnati, OH 45267, USA.
Division of Infectious Diseases, Department of Internal Medicine, University of Cincinnati, 231 Albert Sabin Way, MSB 6109, ML 0560, Cincinnati, OH 45267, USA.
Anaerobe. 2017 Jun;45:101-105. doi: 10.1016/j.anaerobe.2017.02.014. Epub 2017 Feb 20.
Clostridium difficile is the leading cause of healthcare-associated infections in the United States. Clinically, C. difficile-associated disease can present as asymptomatic colonization, self-limited diarrheal illness or severe colitis (that may result in death). This variability in disease course and outcomes suggests that host factors play an important role as key determinants of disease severity. Currently, there are several scoring indices to estimate severity of C. difficile-associated disease. Leukocytosis and renal failure are considered to be the most important predictors of C. difficile disease severity in hosts with a normal immune system. The degree of leukocytosis which is considered significant for severe disease and how it is scored vary amongst scoring indices. None of the scores have been prospectively validated, and while total WBC count is useful to estimate the magnitude of the host response in most patient populations, in immune-compromised patients like those receiving chemotherapy, solid organ transplant patients or hematopoietic stem cell transplants the WBC response can be variable or even absent making this marker of severity difficult to interpret. Other cellular subsets like neutrophils, eosinophils and lymphocytes provide important information about the host immune status and play an important role in the immune response against C. difficile infection. However, under the current scoring systems the role of these cellular subsets have been underestimated and only total white blood cell counts are taken into account. In this review we highlight the role of host leukocyte response to C. difficile challenge in the normal and immunocompromised host, and propose possible ways that would allow for a better representation of the different immune cell subsets (neutrophils, lymphocytes and eosinophils) in the current scoring indices.
艰难梭菌是美国医疗保健相关感染的主要原因。临床上，艰难梭菌相关疾病可表现为无症状定植、自限性腹泻疾病或严重结肠炎（可能导致死亡）。疾病进程和结果的这种变异性表明宿主因素作为疾病严重程度的关键决定因素起着重要作用。目前，有几种评分指数来估计艰难梭菌相关疾病的严重程度。白细胞增多和肾衰竭被认为是免疫系统正常的宿主中艰难梭菌疾病严重程度的最重要预测指标。对于严重疾病被认为具有显著意义的白细胞增多程度及其评分方式在不同的评分指数中有所不同。没有一个评分指数经过前瞻性验证，虽然在大多数患者群体中白细胞总数有助于估计宿主反应的程度，但在免疫受损患者中，如接受化疗的患者、实体器官移植患者或造血干细胞移植患者，白细胞反应可能可变甚至缺乏，使得这个严重程度标志物难以解释。其他细胞亚群，如中性粒细胞、嗜酸性粒细胞和淋巴细胞，提供了关于宿主免疫状态的重要信息，并在针对艰难梭菌感染的免疫反应中发挥重要作用。然而，在当前的评分系统下，这些细胞亚群的作用被低估了，只考虑了白细胞总数。在这篇综述中，我们强调了正常宿主和免疫受损宿主中宿主白细胞对艰难梭菌挑战的反应的作用，并提出了可能的方法，以便在当前的评分指数中更好地体现不同的免疫细胞亚群（中性粒细胞、淋巴细胞和嗜酸性粒细胞）。
