Marcinak John F, Frank Arthur L
Department of Pediatrics, University of Chicago, Chicago, Illinois, USA.
Curr Opin Infect Dis. 2003 Jun;16(3):265-9. doi: 10.1097/00001432-200306000-00014.
The concept of methicillin-resistant Staphylococcus aureus (MRSA) associated with broad resistance, nosocomial acquisition, and known risk factors has recently been expanded. A new type of MRSA that is resistant to fewer antibiotics has emerged in pediatric practice since the mid-1990s. These isolates are community acquired and have been reported from diverse geographic regions. Awareness of these organisms is important for appropriate treatment of S. aureus infections in children.
Community-acquired MRSA (CA-MRSA) isolates are similar in many respects to community-acquired methicillin-susceptible S. aureus (CA-MSSA). There are usually no differences in risk factors between children with CA-MRSA infections and those with CA-MSSA infections or their household contacts. In one study, however, multivariate analysis showed that age greater than 1 year and health care contact in the preceding month were significant risk factors for CA-MRSA. Skin and soft tissue infections are the most common manifestations, although serious invasive infections and death may occur. Pneumonia has been reported more often in children with CA-MRSA than in those with CA-MSSA. Clindamycin is an effective therapy for CA-MRSA, but there is a risk for development of clindamycin resistance during treatment of a CA-MRSA that is clindamycin susceptible and inducibly erythromycin resistant. Trimethoprim-sulfamethoxazole is likely to be effective, and linezolid is a new option for treatment.
The appearance of CA-MRSA has important implications for therapy of infections caused by S. aureus in children. Three specific issues are the development of resistance during clindamycin therapy, insufficient data on the use of trimethoprim-sulfamethoxazole in serious CA-MRSA infections, and the appropriate role for newer antibiotics such as linezolid.
耐甲氧西林金黄色葡萄球菌(MRSA)与广泛耐药、医院获得性感染及已知危险因素相关的概念最近有所扩展。自20世纪90年代中期以来,儿科临床中出现了一种对较少抗生素耐药的新型MRSA。这些菌株是社区获得性的,已在不同地理区域被报道。认识这些微生物对于儿童金黄色葡萄球菌感染的恰当治疗很重要。
社区获得性MRSA(CA-MRSA)菌株在许多方面与社区获得性甲氧西林敏感金黄色葡萄球菌(CA-MSSA)相似。CA-MRSA感染儿童与CA-MSSA感染儿童或其家庭接触者之间的危险因素通常没有差异。然而,在一项研究中,多变量分析显示年龄大于1岁及前一个月有医疗接触史是CA-MRSA的重要危险因素。皮肤和软组织感染是最常见的表现,尽管可能发生严重的侵袭性感染和死亡。据报道,CA-MRSA感染儿童比CA-MSSA感染儿童发生肺炎的情况更常见。克林霉素是治疗CA-MRSA的有效药物,但在治疗对克林霉素敏感且诱导性耐红霉素的CA-MRSA时,存在产生克林霉素耐药的风险。复方磺胺甲恶唑可能有效,利奈唑胺是一种新的治疗选择。
CA-MRSA的出现对儿童金黄色葡萄球菌感染的治疗具有重要意义。三个具体问题是克林霉素治疗期间耐药性的产生、复方磺胺甲恶唑在严重CA-MRSA感染中应用的数据不足以及利奈唑胺等新型抗生素的恰当作用。