Mendes Rodrigo E, Costello Andrew J, Jacobs Michael R, Biek Donald, Critchley Ian A, Jones Ronald N
JMI Laboratories, North Liberty, IA, USA.
JMI Laboratories, North Liberty, IA, USA.
Diagn Microbiol Infect Dis. 2014 Sep;80(1):19-25. doi: 10.1016/j.diagmicrobio.2014.05.020. Epub 2014 May 24.
This study evaluated pneumococci cultured from blood or lower respiratory tract specimens from hospitalized patients in the USA (all age groups) during 2011-2012 (N = 1190) and compared findings with those from a similar study performed in 2008 (N = 694). Isolates were tested for susceptibility by broth microdilution and serotypes determined by cpsB sequencing, supplemented with multiplex PCR and capsular swelling assays. Relative percentages of 7-valent pneumococcal conjugate vaccine (PCV7) types were 6.3 and 4.9% in 2008 and 2011-2012, respectively, and the most common PCV7 serotypes (19F and 6B) comprised only 3.7% and 4.0% of all isolates from both periods, respectively. Thirteen-valent pneumococcal conjugate vaccine (PCV13) serotypes represented 42.9% of isolates in 2008 and 30.1% in the second period, and this decrease was driven by 19A and 7F. Non-PCV13 serogroups/serotypes 23A, 15B/15C, 7C, 8, and 31 increased. Penicillin non-susceptibility rates were 9.6-10.0% and 38.9-42.7% when applying the parenteral (i.e. ≥ 4 μg/mL) and oral breakpoints (i.e. ≥ 0.12 μg/mL), respectively. Ceftaroline was the most potent agent tested based on MIC50 and MIC90 values (≤ 0.015 and 0.12 μg/mL, respectively) for both time periods.
本研究评估了2011 - 2012年期间美国（所有年龄组）住院患者血液或下呼吸道标本中培养出的肺炎球菌（N = 1190），并将结果与2008年进行的一项类似研究（N = 694）的结果进行了比较。通过肉汤微量稀释法检测分离株的药敏性，通过cpsB测序确定血清型，并辅以多重PCR和荚膜肿胀试验。2008年和2011 - 2012年，7价肺炎球菌结合疫苗（PCV7）型的相对百分比分别为6.3%和4.9%，两个时期最常见的PCV7血清型（19F和6B）分别仅占所有分离株的3.7%和4.0%。13价肺炎球菌结合疫苗（PCV13）血清型在2008年占分离株的42.9%，在第二个时期占30.1%，这种下降是由19A和7F导致的。非PCV13血清群/血清型23A、15B/15C、7C、8和31有所增加。分别应用肠外（即≥4μg/mL）和口服折点（即≥0.12μg/mL）时，青霉素不敏感率分别为9.6 - 10.0%和38.9 - 42.7%。基于两个时期的MIC50和MIC90值（分别≤0.015和0.12μg/mL），头孢洛林是测试的最有效药物。
