Pfaller M A, Ehrhardt A F, Jones R N
CAST Laboratories and the University of Iowa College of Medicine, Iowa City, Iowa 52242, USA.
Am J Med. 2001 Dec 17;111 Suppl 9A:4S-12S; discussion 36S-38S. doi: 10.1016/s0002-9343(01)01025-7.
Continuing problems of antimicrobial resistance have prompted the initiation of several surveillance programs. Few, if any, of these programs focus on community-acquired respiratory tract infections seen in routine office-based practices. The Respiratory Surveillance Program (RESP; 1999-2000) in 674 community-based physician office practices in the United States determined the frequency of potential bacterial pathogens including Streptococcus pneumoniae, Haemophilus influenzae, and Moraxella catarrhalis in patients diagnosed clinically with community-acquired pneumonia, acute exacerbations of chronic bronchitis, and sinusitis throughout all 9 US census/geographic regions. Susceptibility to the penicillins (ampicillin, penicillin), oral cephalosporins, fluoroquinolones (gatifloxacin, levofloxacin, ciprofloxacin), macrolides (erythromycin, azithromycin, clarithromycin), tetracycline, and trimethoprim/sulfamethoxazole was determined by reference methods. Patients were required to have a culturable focus of infection, and specimens were immediately sent to a reference laboratory. Among 22,689 total specimens (610 community-acquired pneumonia, 4,779 acute exacerbation of chronic bronchitis, 16,213 sinusitis, 1,087 other), H influenzae was the most commonly isolated organism from patients with community-acquired pneumonia (38%) and acute exacerbation of chronic bronchitis (35%) in all nine geographic regions. S pneumoniae was isolated in 18% of community-acquired pneumonia cases, 13% of acute exacerbation of chronic bronchitis cases, and 11% of sinusitis cases. M catarrhalis was most commonly isolated from the nasopharynx of patients with sinusitis (29%). High-level resistance to penicillin (2 microg/mL or greater; 16% overall) and the macrolides (32% to 35%) among S pneumoniae varied both with site of infection and with geographic region. The greatest resistance was observed among isolates from the nasopharynx of patients with sinusitis and from patients from the East South Central or South Atlantic regions of the United States. Although the susceptibility of H influenzae and M catarrhalis to the tested antimicrobials did not vary with the type of infection, beta-lactamase-mediated resistance to ampicillin among H influenzae ranged from 15% in New England to 32% in the East South Central region. The fluoroquinolones were highly active against these cultured isolates from community-acquired respiratory tract infection patients, with >99% of all S pneumoniae, H influenzae, and M catarrhalis strains susceptible to gatifloxacin (MIC(90), 0.5 microg/mL) and levofloxacin (MIC(90), 2 microg/mL). The extended-spectrum fluoroquinolones appear well suited for community-acquired respiratory tract infection therapy, including pathogens other than pneumococcus, H influenzae, and M catarrhalis.
持续存在的抗菌药物耐药问题促使启动了多项监测计划。这些计划中几乎没有（即便有也很少）关注在常规门诊实践中出现的社区获得性呼吸道感染。美国674家社区医生诊所开展的呼吸道监测计划（RESP；1999 - 2000年）确定了在临床诊断为社区获得性肺炎、慢性支气管炎急性加重和鼻窦炎的患者中，包括肺炎链球菌、流感嗜血杆菌和卡他莫拉菌在内的潜在细菌病原体的出现频率，涵盖了美国所有9个人口普查/地理区域。通过参考方法确定了对青霉素（氨苄西林、青霉素）、口服头孢菌素、氟喹诺酮类（加替沙星、左氧氟沙星、环丙沙星）、大环内酯类（红霉素、阿奇霉素、克拉霉素）、四环素和甲氧苄啶/磺胺甲恶唑的敏感性。要求患者有可培养的感染灶，标本立即送往参考实验室。在总共22,689份标本中（610份社区获得性肺炎、4,779份慢性支气管炎急性加重、16,213份鼻窦炎、1,087份其他），流感嗜血杆菌是在所有九个地理区域中社区获得性肺炎患者（38%）和慢性支气管炎急性加重患者（35%）中最常分离出的病原体。肺炎链球菌在18%的社区获得性肺炎病例、13%的慢性支气管炎急性加重病例和11%的鼻窦炎病例中被分离出。卡他莫拉菌最常从鼻窦炎患者的鼻咽部分离出（29%）。肺炎链球菌对青霉素（2微克/毫升或更高；总体为16%）和大环内酯类（32%至35%）的高水平耐药性因感染部位和地理区域而异。在美国东南部中东部或南大西洋地区的患者的鼻咽部分离株以及这些地区的患者中观察到最大耐药性。尽管流感嗜血杆菌和卡他莫拉菌对所测试抗菌药物的敏感性不因感染类型而异，但流感嗜血杆菌中β - 内酰胺酶介导的对氨苄西林的耐药性在新英格兰地区为15%，在东南部中东部地区为32%。氟喹诺酮类对这些从社区获得性呼吸道感染患者中培养出的分离株具有高度活性，所有肺炎链球菌、流感嗜血杆菌和卡他莫拉菌菌株中>99%对加替沙星（MIC90，0.5微克/毫升）和左氧氟沙星（MIC90，2微克/毫升）敏感。广谱氟喹诺酮类似乎非常适合社区获得性呼吸道感染的治疗，包括肺炎球菌、流感嗜血杆菌和卡他莫拉菌以外的病原体。
