Asseray Nathalie, Papin Christophe, Touchais Sophie, Bemer Pascale, Lambert Chantal, Boutoille David, Tequi Brigitte, Gouin François, Raffi François, Passuti Norbert, Potel Gilles
Université de Nantes, Faculté de Médecine, Thérapeutiques Cliniques et Expérimentales des Infections, Nantes, France.
Scand J Infect Dis. 2010 Jul;42(6-7):421-5. doi: 10.3109/00365540903527330.
The identification of Propionibacterium acnes in cultures of bone and joint samples is always difficult to interpret because of the ubiquity of this microorganism. The aim of this study was to propose a diagnostic strategy to distinguish infections from contaminations. This was a retrospective analysis of all patient charts of those patients with >or=1 deep samples culture-positive for P. acnes. Every criterion was tested for sensitivity, specificity, and positive likelihood ratio, and then the diagnostic probability of combinations of criteria was calculated. Among 65 patients, 52 (80%) were considered truly infected with P. acnes, a diagnosis based on a multidisciplinary process. The most valuable diagnostic criteria were: >or=2 positive deep samples, peri-operative findings (necrosis, hardware loosening, etc.), and >or=2 surgical procedures. However, no single criterion was sufficient to ascertain the diagnosis. The following combinations of criteria had a diagnostic probability of >90%: >or=2 positive cultures + 1 criterion among: peri-operative findings, local signs of infection, >or=2 previous operations, orthopaedic devices; 1 positive culture + 3 criteria among: peri-operative findings, local signs of infection, >or=2 previous surgical operations, orthopaedic devices, inflammatory syndrome. The diagnosis of P. acnes osteomyelitis was greatly improved by combining different criteria, allowing differentiation between infection and contamination.
由于痤疮丙酸杆菌在环境中普遍存在，因此在骨与关节样本培养物中鉴定该菌总是难以解释。本研究的目的是提出一种诊断策略，以区分感染与污染。这是一项对所有痤疮丙酸杆菌血培养阳性的深部样本患者病历的回顾性分析。对每个标准进行敏感性、特异性和阳性似然比测试，然后计算标准组合的诊断概率。65例患者中，52例（80%）被认为确实感染了痤疮丙酸杆菌，这一诊断基于多学科流程。最有价值的诊断标准是：≥2份深部样本阳性、围手术期表现（坏死、硬件松动等）以及≥2次外科手术。然而，没有单一标准足以确定诊断。以下标准组合的诊断概率>90%：≥2次培养阳性+围手术期表现、局部感染体征、≥2次既往手术、骨科器械中的1项标准；1次培养阳性+围手术期表现、局部感染体征、≥2次既往外科手术、骨科器械、炎症综合征中的3项标准。通过结合不同标准，痤疮丙酸杆菌骨髓炎的诊断有了很大改善，从而能够区分感染与污染。
