Division of Infectious Diseases, San Martino University Hospital, Genoa, Italy.
Mediterr J Hematol Infect Dis. 2011;3(1):e2011007. doi: 10.4084/MJHID.2011.007. Epub 2011 Jan 25.
Candida is one of the most frequent pathogens isolated in bloodstream infections, and is associated with significant morbidity and mortality. In addition to haematological patients, there are several other populations with a substantial risk of developing invasive candidiasis (IC). These include patients undergoing prolonged hospitalisation with the use of broad-spectrum antibiotics, those fitted with intravascular catheters, admitted to both adult and neonate intensive care units (ICU) or gastrointestinal surgery wards and subjects with solid tumours undergoing cytotoxic chemotherapy. As a general rule, every immunocompromised patient might be at risk of Candida infection, including, for example, diabetic patients.The epidemiology of species responsible for IC has been changing, both at local and worldwide level, shifting from C. albicans to non-albicans species, that can be intrinsically resistant to fluconazole (C. krusei and, to some extent, C. glabrata), difficult to eradicate because of biofilm production (C. parapsilosis) or than might acquire resistance to azole during therapy.Delaying the specific therapy has been shown to increase morbidity and mortality, but traditional microbiological diagnosis is poorly sensitive and slow. Thus, culture-based treatment may result in therapy started too late. In order to reduce the mortality in IC, several management strategies have been developed: prophylaxis, empirical and pre-emptive therapy. Compared to prophylaxis, the latter approaches allow to reduce the use of antifungals by targeting only patients at very high risk of IC. Non-invasive serological markers and scores based on clinical prediction rules such as the presence of risk factors or Candida colonisation, have been developed with the aim of allowing prompt initiation of treatment. Although the use of these diagnostic tools in pre-emptive strategies is promising, the performance and cost-effectiveness should be tested in large trials.Agents recommended for initial treatment of candidemia in severely ill patients include echinocandins and lipid formulations of amphotericin B, while stable patients without risk factors for azole-resistance might be treated with fluconazole.
念珠菌是血流感染中最常分离到的病原体之一，与较高的发病率和死亡率相关。除血液系统疾病患者外，还有其他几种发生侵袭性念珠菌病（IC）风险较高的人群。这些人群包括：接受广谱抗生素治疗且住院时间较长的患者、置管患者、入住成人和新生儿重症监护病房（ICU）或胃肠外科病房的患者，以及接受细胞毒性化疗的实体瘤患者。一般来说，每个免疫功能低下的患者都可能有感染念珠菌的风险，例如糖尿病患者。引起 IC 的物种的流行病学在本地和全球范围内都发生了变化，从白念珠菌转变为非白念珠菌，这些念珠菌可能对氟康唑固有耐药（克柔念珠菌和在一定程度上光滑念珠菌），由于生物膜的产生而难以根除（近平滑念珠菌），或者在治疗过程中可能获得对唑类药物的耐药性。延迟特定治疗已被证明会增加发病率和死亡率，但传统的微生物学诊断敏感性差且速度较慢。因此，基于培养的治疗可能导致治疗开始太晚。为了降低 IC 的死亡率，已经制定了几种管理策略：预防、经验性和抢先治疗。与预防相比，后两种方法仅针对极高危 IC 患者，可减少抗真菌药物的使用。为了能够及时开始治疗，已经开发了基于非侵入性血清学标志物和基于临床预测规则（如危险因素或念珠菌定植的存在）的评分。尽管在抢先治疗策略中使用这些诊断工具很有前景，但应在大型试验中测试其性能和成本效益。对于重症患者的初始治疗，建议使用棘白菌素类药物和两性霉素 B 脂质制剂，而没有唑类耐药危险因素的稳定患者可以用氟康唑治疗。
