Pannaraj Pia S, Hulten Kristina G, Gonzalez Blanca E, Mason Edward O, Kaplan Sheldon L
Section of Infectious Diseases, Department of Pediatrics, Baylor College of Medicine and Texas Children's Hospital, Houston, TX 77030, USA.
Clin Infect Dis. 2006 Oct 15;43(8):953-60. doi: 10.1086/507637. Epub 2006 Sep 1.
Cases of pyomyositis and myositis have been increasing in frequency at Texas Children's Hospital (Houston) since 2000. The increase appears to correlate with the emergence of community-acquired methicillin-resistant Staphylococcus aureus (MRSA).
The medical records of patients with pyomyositis and myositis hospitalized at Texas Children's Hospital during the period from January 2000 through December 2005 were reviewed. Available S. aureus isolates were obtained for susceptibility testing, to determine the presence of pvl (lukS-PV and lukF-PV), and for pulsed-field gel electrophoresis analysis.
Forty-five previously healthy children with bacterial pyomyositis or myositis were analyzed. The causes were S. aureus (in 57.8% of children) and Streptococcus pyogenes (in 2.2%); 40.0% of children had negative culture results. The number of cases increased between 2000 and 2005, primarily as a result of an increase in the prevalence of community-acquired MRSA. The mean patient age was 5.5 years (range, 0.06-15 years). The thigh (40.0% of children) and pelvis (28.9%) were the most commonly affected sites. The mean abscess diameter was 3.5 cm. Eighteen children required at least 1 muscle drainage procedure. Of the 24 available S. aureus isolates (15 community-acquired MRSA isolates and 9 community-acquired, methicillin-susceptible S. aureus [MSSA] isolates), 16 were found to be USA300 by pulsed-field gel electrophoresis, and 17 carried pvl. Patients with community-acquired MRSA, USA300, and/or pvl-positive strains required more drainage procedures than did those with community-acquired MSSA, non-USA300, and/or pvl-negative strains (81% vs. 40% [P=.05], 82% vs. 29% [P=.02], and 81% vs. 38% [P=.07], respectively).
Community-acquired MRSA is an increasing cause of pyomyositis and myositis in children. Community-acquired MRSA, USA300, pvl-positive S. aureus isolates caused more severe disease than did community-acquired MSSA, non-USA300, and pvl-negative isolates, respectively.
自2000年以来，德克萨斯儿童医院（休斯顿）的脓性肌炎和肌炎病例数量一直在增加。这种增加似乎与社区获得性耐甲氧西林金黄色葡萄球菌（MRSA）的出现有关。
回顾了2000年1月至2005年12月期间在德克萨斯儿童医院住院的脓性肌炎和肌炎患者的病历。获取可用的金黄色葡萄球菌分离株进行药敏试验，以确定是否存在pvl（lukS-PV和lukF-PV），并进行脉冲场凝胶电泳分析。
分析了45名以前健康的细菌性脓性肌炎或肌炎儿童。病因是金黄色葡萄球菌（57.8%的儿童）和化脓性链球菌（2.2%）；40.0%的儿童培养结果为阴性。2000年至2005年期间病例数增加，主要是由于社区获得性MRSA患病率上升。患者平均年龄为5.5岁（范围0.06 - 15岁）。大腿（40.0%的儿童）和骨盆（28.9%）是最常受累的部位。脓肿平均直径为3.5厘米。18名儿童至少需要进行1次肌肉引流手术。在24株可用的金黄色葡萄球菌分离株中（15株社区获得性MRSA分离株和9株社区获得性、甲氧西林敏感金黄色葡萄球菌[MSSA]分离株），通过脉冲场凝胶电泳发现16株为USA300，17株携带pvl。社区获得性MRSA、USA300和/或pvl阳性菌株的患者比社区获得性MSSA、非USA300和/或pvl阴性菌株的患者需要更多的引流手术（分别为81%对40%[P = 0.05]、82%对29%[P = 0.02]和81%对38%[P = 0.07]）。
社区获得性MRSA是儿童脓性肌炎和肌炎日益增加的病因。社区获得性MRSA、USA300、pvl阳性金黄色葡萄球菌分离株分别比社区获得性MSSA、非USA300和pvl阴性分离株引起更严重的疾病。
