美国科学家近日研究发现一种能够造成儿童耳部感染的肺炎链球菌菌株，该菌株不在肺炎球菌7价共轭疫苗的预防范围内，并且对所有美国食品与药物管理局（FDA）批准的治疗耳部感染的抗生素均具有抗药性，相关论文10月15日发表在《美国医学协会期刊》（JAMA）上。
细菌性呼吸道感染的最常见原因，就是对肺炎球菌抗生素产生抗药性，这也一直是儿科医学的一个研究重点。
此次研究由美国纽约罗切斯特大学的儿科学医学博士Michael E. Pichichero和Janet R. Casey领导完成。他们表示，2000年在美国推出的肺炎球菌7价共轭疫苗（PCV7）在遏制儿童肺炎球菌感染方面提供了相当乐观的前景，尤其是对耐青霉素和多种药物的菌株产生了有利的影响。
最新研究检测了在推出造成急性中耳炎的肺炎链球菌菌株PCV7之后造成耳部感染的细菌变化状况，尤其注重某些肺炎球菌血清型和抗生素易感性。他们发现了2003年9月至2006年6月期间造成已接受PCV7的儿童患急性中耳炎的肺炎链球菌菌株。
此次研究的所有儿童均来自纽约州罗彻斯特市小儿科，在被诊断患有急性中耳炎的1,816名儿童中，212名儿童接受了鼓膜穿刺术（用针穿刺鼓膜，让液体从中耳流出），这导致了59例肺炎链球菌感染。研究人员发现，一种属于19A血清型的肺炎链球菌菌株是一种新的基因型，对美国食品与药物管理局（FDA）批准用于急性中耳炎儿童患者的所有抗生素均具有抗药性。一共有九例感染这种菌株，两例在2003-2004年，两例在2004-2005年，另外有五例在2005-2006年。
（《美国医学协会期刊》（JAMA）2007年第298(15)期，Michael E. Pichichero，Janet R. Casey）
原始出处:
JAMA
Vol. 298 No. 15, October 17, 2007
Emergence of a Multiresistant Serotype 19A Pneumococcal Strain Not Included in the 7-Valent Conjugate Vaccine as an Otopathogen in Children
Michael E. Pichichero, MD; Janet R. Casey, MD
JAMA. 2007;298:1772-1778.
Context Concern has been raised about the possible emergence of a bacterial strain that is untreatable by US Food and Drug Administration (FDA)–approved antibiotics and that causes acute otitis media (AOM) in children.
Objective To monitor continuing shifts in the strains of Streptococcus pneumoniae that cause AOM, with particular attention to capsular serotypes and antibiotic susceptibility, following the introduction of a pneumococcal 7-valent conjugate vaccine (PCV7).
Design, Setting, and Patients Prospective cohort study using tympanocentesis to identify S pneumoniae strains that caused AOM in children receiving PCV7 between September 2003 and June 2006. All children were from a Rochester, New York, pediatric practice.
Main Outcome Measure Determination of serotypes and antibiotic susceptibility of S pneumoniae causing AOM.
Results Among 1816 children in whom AOM was diagnosed, tympanocentesis was performed in 212, yielding 59 cases of S pneumoniae infection. One strain of S pneumoniae belonging to serotype 19A was a new genotype and was resistant to all antibiotics approved by the FDA for use in children with AOM. This strain was identified in 9 cases (2 in 2003-2004, 2 in 2004-2005, and 5 in 2005-2006). Four children infected with this strain had been unsuccessfully treated with 2 or more antibiotics, including high-dose amoxicillin or amoxicillin-clavulanate and 3 injections of ceftriaxone; 3 had recurrent AOM; and for 2 others, the infection was their first in life. The first 4 cases required tympanostomy tube insertion after additional unsuccessful antibiotic therapies. Levofloxacin was used in the subsequent 5 cases, with resolution of infection without surgery.
Conclusion In the years following introduction of PCV7, a strain of S pneumoniae has emerged in the United States as an otopathogen that is resistant to all FDA-approved antibiotics for treatment of AOM in children.
Author Affiliations: University of Rochester and Legacy Pediatrics, Rochester, New York.
