Lavergne V, Malo M, Gaudelli C, Laprade M, Leduc S, Laflamme P, Rouleau D M
Service de microbiologie médicale et infectiologie, hôpital du Sacré-Cœur de Montréal, 5400, boulevard Gouin O, C-2095, Montréal, H4J 1C5 Québec, Canada; Faculté de microbiologie, infectiologie et immunologie, université de Montréal, 2900, boulevard Édouard-Montpetit, Montréal, H3T 1J4 Québec, Canada.
Faculté de médecine, université de Montréal, 2900, boulevard Édouard-Montpetit, Montréal, H3T 1J4e Québec, Canada; Service de chirurgie orthopédique, hôpital du Sacré-Cœur de Montréal, 5400, boulevard Gouin O, C-2095, H4J 1C5 Montreal, Quebec, Canada.
Orthop Traumatol Surg Res. 2017 Apr;103(2):307-314. doi: 10.1016/j.otsr.2016.12.005. Epub 2017 Jan 5.
The clinical significance of a positive culture to Propionibacterium acnes in orthopedic specimens remains unclear, whether about its role as a contaminant or a pathogen, or its impact as a coinfectant. Therefore, we performed a retrospective study to provide a more accurate description of the clinical impact of P. acnes in an orthopedic population aiming to determine: 1) if there is a clinical difference between P. acnes infection and contamination? 2) If there is a clinical difference between P. acnes monoinfection, and coinfection.
There is a clinical difference between P. acnes infection and contamination.
Patients were selected over a five-year period, and those with a minimum of one positive culture for P. acnes, from any intraoperative orthopedic tissue sample, were included in the study. P. acnes infection was defined as the isolation of P. acnes from≥2 specimens, or in only one specimen, in the presence of typical perioperative findings and/or local signs of infection.
A total of 68 patients had a positive P. acnes culture, 35 of which were considered to be infected. The infections affected mostly males (29/35-83%), occurred mostly in shoulders (22/35-63%), and at a site already containing an orthopedic implant (32/35-91%). Local inflammatory signs were present in half of the cases when an infection was diagnosed. Coinfection with other pathogens was present in 31% of patients (11/35). When comparing patients coinfected with P. acnes, and those who were monoinfected, the latter presented less often with local inflammatory signs. Recurrence rate was 24% (8/35) and the only risk factor for recurrence was the presence of a monoinfection.
This study confirms the pathogenicity of P. acnes in an orthopedic population, as it is present in multiple samples in the same patient, and because it is present in cultures from cases with clinical recurrence. Our study showed that monoinfections differ from coinfections mainly by their higher risk of recurrence.
Level IV retrospective case series.
骨科标本中痤疮丙酸杆菌培养阳性的临床意义仍不明确，无论是其作为污染物还是病原体的作用，亦或是作为合并感染源的影响。因此，我们进行了一项回顾性研究，以更准确地描述痤疮丙酸杆菌在骨科患者中的临床影响，旨在确定：1）痤疮丙酸杆菌感染与污染在临床上是否存在差异？2）痤疮丙酸杆菌单一感染与合并感染在临床上是否存在差异？
痤疮丙酸杆菌感染与污染在临床上存在差异。
选取五年期间的患者，纳入标准为任何术中骨科组织样本中至少有一次痤疮丙酸杆菌培养阳性。痤疮丙酸杆菌感染定义为从≥2份标本中分离出痤疮丙酸杆菌，或在仅一份标本中分离出痤疮丙酸杆菌，同时伴有典型的围手术期表现和/或局部感染体征。
共有68例患者痤疮丙酸杆菌培养呈阳性，其中35例被认为感染。感染主要影响男性（29/35 - 83%），大多发生在肩部（22/35 - 63%），且发生在已植入骨科植入物的部位（32/35 - 91%）。诊断为感染时，半数病例出现局部炎症体征。31%的患者（11/35）存在与其他病原体的合并感染。在比较合并痤疮丙酸杆菌感染的患者与单一感染的患者时，后者出现局部炎症体征的频率较低。复发率为24%（8/35），复发的唯一危险因素是单一感染。
本研究证实了痤疮丙酸杆菌在骨科患者中的致病性，因为它存在于同一患者的多个样本中，且存在于临床复发病例的培养物中。我们的研究表明，单一感染与合并感染的主要区别在于其复发风险更高。
IV级回顾性病例系列。
