Department of Emergency Medicine, Brigham and Women's Hospital, Boston, MA, USA.
Clin Infect Dis. 2013 Jun;56(12):1754-62. doi: 10.1093/cid/cit122. Epub 2013 Mar 1.
Community-associated methicillin-resistant S. aureus (CA-MRSA) is the most common organism isolated from purulent skin infections. Antibiotics are usually not beneficial for skin abscess, and national guidelines do not recommend CA-MRSA coverage for cellulitis, except purulent cellulitis, which is uncommon. Despite this, antibiotics targeting CA-MRSA are prescribed commonly and increasingly for skin infections, perhaps due, in part, to lack of experimental evidence among cellulitis patients. We test the hypothesis that antibiotics targeting CA-MRSA are beneficial in the treatment of cellulitis.
We performed a randomized, multicenter, double-blind, placebo-controlled trial from 2007 to 2011. We enrolled patients with cellulitis, no abscesses, symptoms for <1 week, and no diabetes, immunosuppression, peripheral vascular disease, or hospitalization (clinicaltrials.gov NCT00676130). All participants received cephalexin. Additionally, each was randomized to trimethoprim-sulfamethoxazole or placebo. We provided 14 days of antibiotics and instructed participants to continue therapy for ≥1 week, then stop 3 days after they felt the infection to be cured. Our main outcome measure was the risk difference for treatment success, determined in person at 2 weeks, with telephone and medical record confirmation at 1 month.
We enrolled 153 participants, and 146 had outcome data for intent-to-treat analysis. Median age was 29, range 3-74. Of intervention participants, 62/73 (85%) were cured versus 60/73 controls (82%), a risk difference of 2.7% (95% confidence interval, -9.3% to 15%; P = .66). No covariates predicted treatment response, including nasal MRSA colonization and purulence at enrollment.
Among patients diagnosed with cellulitis without abscess, the addition of trimethoprim-sulfamethoxazole to cephalexin did not improve outcomes overall or by subgroup.
NCT00676130.
社区相关性耐甲氧西林金黄色葡萄球菌（CA-MRSA）是从脓性皮肤感染中分离出的最常见的病原体。抗生素通常对皮肤脓肿无益，且国家指南不建议对蜂窝织炎使用 CA-MRSA 覆盖，除非是不常见的脓性蜂窝织炎。尽管如此，针对 CA-MRSA 的抗生素仍被广泛且越来越多地用于皮肤感染的治疗，这可能部分归因于蜂窝织炎患者缺乏实验证据。我们检验了这样一个假设，即针对 CA-MRSA 的抗生素在治疗蜂窝织炎方面是有益的。
我们于 2007 年至 2011 年进行了一项随机、多中心、双盲、安慰剂对照试验。我们招募了患有蜂窝织炎、无脓肿、症状持续时间<1 周且无糖尿病、免疫抑制、外周血管疾病或住院治疗的患者（clinicaltrials.gov NCT00676130）。所有参与者均接受头孢氨苄治疗。此外，每位参与者还随机分为甲氧苄啶-磺胺甲噁唑或安慰剂组。我们提供了 14 天的抗生素，并指导参与者继续治疗至少 1 周，然后在他们感到感染已治愈的 3 天后停止治疗。我们的主要结局指标是治疗成功的风险差异，在 2 周时进行面对面评估，并在 1 个月时通过电话和病历确认。
我们共纳入了 153 名参与者，其中 146 名参与者的意向治疗分析数据完整。中位年龄为 29 岁，范围为 3-74 岁。在干预组中，73 名参与者中有 62 名（85%）治愈，而对照组中有 73 名参与者中的 60 名（82%）治愈，风险差异为 2.7%（95%置信区间为-9.3%至 15%；P=.66）。没有协变量可以预测治疗反应，包括鼻 MRSA 定植和入组时的脓性分泌物。
在诊断为无脓肿的蜂窝织炎患者中，头孢氨苄联合甲氧苄啶-磺胺甲噁唑并不能改善整体或亚组的结局。
NCT00676130。
