Department of Pediatrics, University of Calgary, and Alberta Health Services - Calgary Zone, University of Calgary, Calgary, Alberta.
Department of Pediatrics, University of Calgary, and Alberta Health Services - Calgary Zone, University of Calgary, Calgary, Alberta ; Alberta Children's Hospital Research Institute, University of Calgary, Calgary, Alberta ; Department of Microbiology and Infectious Diseases, University of Calgary, Calgary, Alberta ; Department of Pathology and Laboratory Medicine, University of Calgary, Calgary, Alberta.
Can J Infect Dis Med Microbiol. 2014 Mar;25(2):e71-5. doi: 10.1155/2014/196748.
The recent introduction of the seven-valent pneumococcal conjugate vaccine has led to changes in the proportion of disease caused by different serotypes. The serotypes targeted by the vaccine have been reduced, and Streptococcus pneumonia serotype 19A is now the most commonly isolated serotype causing invasive pneumococcal disease. This serotype has been associated with antibiotic resistance. The authors of this article conducted a review of cases of invasive pneumococcal disease diagnosed between 2000 and 2010 in Calgary, Alberta, to examine the disease course of serotype 19A invasive pneumococcal disease compared with other serotypes.
Streptoccocus pneumoniae serotype 19A (ST19A) became an important cause of invasive pneumococcal disease (IPD) after the introduction of the conjugate vaccine.
To examine the severity and outcome of ST19A IPD compared with non-ST19A IPD.
The Calgary Area Streptococcus pneumoniae Epidemiology Research (CASPER) study collects clinical and laboratory data on all IPD cases in Calgary, Alberta. Analysis was performed on data from 2000 to 2010 comparing ST19A and non-ST19A IPD cases. Adjusted linear and logistic regression models were used to examine outcomes of duration of appropriate intravenous antibiotic therapy and intensive care unit admission, respectively.
ST19A tended to cause disease in younger patients. ST19A isolates were more often multidrug resistant (19% versus 0.3%; P<0.001). Adjusted logistic regression showed no difference in intensive care unit admission between ST19A and non-ST19A IPD cases (OR 1.4 [95% CI 0.8 to 2.7]). An adjusted linear regression model showed patients <18 years of age with a diagnosis of bacteremia and no risk factors infected with ST19A were, on average, treated with antibiotics 1.4 times (95% CI 1.1 to 1.9) as long as patients with non-19A IPD and the same baseline characteristics.
ST19A IPD was associated with an increase in average time on antibiotics. Although many of the infecting strains of ST19A were within the threshold for susceptibility, they may be sufficiently resilient to require a longer duration of antibiotic therapy or higher dose to clear the infection.
ST19A is more common in younger individuals, is more antibiotic resistant and may require longer average treatment duration.
研究比较血清型 19A（ST19A）与非 ST19A 侵袭性肺炎球菌病（IPD）的严重程度和结局。
卡尔加里地区肺炎球菌流行病学研究（CASPER）收集了艾伯塔省卡尔加里所有 IPD 病例的临床和实验室数据。对 2000 年至 2010 年的数据进行分析，比较 ST19A 和非 ST19A IPD 病例。采用调整后的线性和逻辑回归模型分别评估适当静脉内抗生素治疗时间和入住重症监护病房的结局。
ST19A 倾向于引起年轻患者发病。ST19A 分离株更常为多药耐药（19%比 0.3%；P<0.001）。调整后的逻辑回归显示，ST19A 和非 ST19A IPD 病例入住重症监护病房的比例无差异（比值比 1.4[95%CI 0.8 至 2.7]）。调整后的线性回归模型显示，年龄<18 岁且患有菌血症且无危险因素的患者感染 ST19A 时，平均抗生素治疗时间比具有相同基线特征的非 19A IPD 患者长 1.4 倍（95%CI 1.1 至 1.9）。
ST19A IPD 与抗生素平均使用时间增加有关。尽管许多 ST19A 感染株在药敏阈值范围内，但它们可能具有足够的弹性，需要更长的抗生素治疗时间或更高的剂量才能清除感染。
ST19A 在年轻个体中更为常见，对抗生素的耐药性更高，可能需要更长的平均治疗时间。
