Bauer Thomas, Marmor Simon, Ghout Idir, Salomon Elsa, El Sayed Faten, Heym Beate, Ropers Jacques, Rottman Martin, Gaillard Jean-Louis, Roux Anne-Laure
T. Bauer, Service de Chirurgie Orthopédique et Traumatologie, Hôpital Ambroise Paré (Assistance Publique - Hôpitaux de Paris, AP-HP), Boulogne-Billancourt, France.
S. Marmor, Centre de référence des infections ostéo-articulaires, Groupe Hospitalier Diaconesses Croix Saint-Simon, Paris, France.
Clin Orthop Relat Res. 2020 Dec;478(12):2786-2797. doi: 10.1097/CORR.0000000000001392.
Preoperative synovial fluid culture is pivotal in the early diagnosis of prosthetic joint infection (PJI) but may yield false-positive and false-negative results. We evaluated the predictive value of synovial fluid culture results combined with the measurement of serum anti-staphylococcal antibodies (SASA).
QUESTIONS/PURPOSES: (1) For hip and knee PJI, does combining positive SASA results with preoperative synovial culture results improve the positive predictive value (PPV) of preoperative synovial fluid culture alone? (2) Does combining preoperative synovial fluid culture results with a positive cell count and differential result increase the PPV of preoperative synovial fluid culture alone? (3) What proportion of isolated organisms exhibit concordance in antibiotic susceptibility: preoperative aspiration versus intraoperative isolates?
A prospective study was conducted at two French reference centers that manage bone and joint infections and included 481 adult patients who had a revision or resection arthroplasty between June 25, 2012 and June 23, 2014. Exclusion criteria including no serum sample available for immunoassay, the lack of microbiological documentation, and the absence of preoperative aspiration reduced the patient number to 353. Seven patients with an undetermined SASA result were excluded from the analysis. We also excluded patients with PJI involving more than one Staphylococcus species (polystaphylococcal infection) and those in whom more than one Staphylococcus species was recovered from the preoperative synovial fluid culture (polystaphylococcal synovial fluid culture). In total, 340 patients were included in the analysis (no infection, 67% [226 of 340]; staphylococcal infection, 21% [71 of 340]; other infection, 13% [43 of 340]). The preoperative synovial fluid analysis included a cell count and differential and bacterial culture. SASAs were measured using a multiplex immunoassay. The diagnosis of PJI was determined using the Infectious Diseases Society of America (IDSA) criteria [] and intraoperative tissue culture at the time of revision surgery was used as the gold standard (at least one positive intraoperative sample for a "virulent" organism (such as S. aureus) or two positive samples for a "non-virulent" (for example S. epidermidis).
SASA increased the PPV compared with synovial fluid culture alone (92% [95% CI 82 to 97] versus 79% [95% CI 68 to 87]; p = 0.04); when stratified by site, an increase in PPV was seen in hip infections (100% [95% CI 89 to 100] versus 77% [95% CI 63 to 88]; p = 0.01) but not in knee infections (84% [95% CI 66 to 95] versus 80% [95% CI 64 to 91]; p = 0.75). A positive cell count and differential result increased the PPV of staphylococcal synovial fluid cultures compared with synovial fluid culture alone (86% [95% CI 70 to 95] versus 79% [95% CI 68 to 87]; p = 0.36); when stratified by site, no difference in hip and knee infections was observed (86% [95% CI 67 to 96] versus 77% [95% CI 63 to 88]; p = 0.42) and 86% [95% CI 70 to 95] versus 80% [95% CI 64 to 91]; p = 0.74).
SASA measurement improves the predictive value of synovial fluid cultures of the hip for all staphylococcal organisms, including coagulase-negative staphylococci, but the PPV of SASA plus synovial fluid culture it is not superior to the PPV of synovial fluid cell count/differential plus synovial culture for the knee.
Level III, diagnostic study.
术前滑膜液培养对人工关节感染（PJI）的早期诊断至关重要，但可能产生假阳性和假阴性结果。我们评估了滑膜液培养结果与血清抗葡萄球菌抗体（SASA）检测相结合的预测价值。
问题/目的：（1）对于髋和膝PJI，将阳性SASA结果与术前滑膜培养结果相结合，是否能提高单独术前滑膜液培养的阳性预测值（PPV）？（2）将术前滑膜液培养结果与阳性细胞计数及分类结果相结合，是否能提高单独术前滑膜液培养的PPV？（3）分离出的微生物中，术前穿刺与术中分离株在抗生素敏感性方面一致的比例是多少？
在法国两个管理骨与关节感染的参考中心进行了一项前瞻性研究，纳入了2012年6月25日至2014年6月23日期间接受翻修或切除关节成形术的481例成年患者。排除标准包括无血清样本用于免疫测定、缺乏微生物学记录以及未进行术前穿刺，这使患者数量减少至353例。7例SASA结果未确定的患者被排除在分析之外。我们还排除了涉及多种葡萄球菌属的PJI患者（多葡萄球菌感染）以及术前滑膜液培养中分离出多种葡萄球菌属的患者（多葡萄球菌滑膜液培养）。总共340例患者纳入分析（无感染，67%[340例中的226例]；葡萄球菌感染，21%[340例中的71例]；其他感染，13%[340例中的43例]）。术前滑膜液分析包括细胞计数及分类和细菌培养。使用多重免疫测定法检测SASA。采用美国传染病学会（IDSA）标准确定PJI诊断，翻修手术时的术中组织培养用作金标准（至少一份术中样本对“致病”微生物（如金黄色葡萄球菌）呈阳性，或两份样本对“非致病”微生物（如表皮葡萄球菌）呈阳性）。
与单独滑膜液培养相比，SASA提高了PPV（92%[95%CI 82至97]对79%[95%CI 68至87]；p = 0.04）；按部位分层时，髋部感染的PPV有所增加（100%[95%CI 89至100]对77%[95%CI 63至88]；p = 0.01），但膝部感染未增加（84%[95%CI 66至95]对80%[95%CI 64至91]；p = 0.75）。与单独滑膜液培养相比，阳性细胞计数及分类结果提高了葡萄球菌滑膜液培养的PPV（86%[95%CI 70至95]对79%[95%CI 68至87]；p = 0.36）；按部位分层时，髋部和膝部感染未观察到差异（86%[95%CI 67至96]对77%[95%CI 63至88]；p = 0.42）以及86%[95%CI 70至95]对80%[95%CI 64至91]；p = 0.74）。
SASA检测提高了髋部滑膜液培养对所有葡萄球菌属微生物（包括凝固酶阴性葡萄球菌）的预测价值，但SASA加滑膜液培养的PPV并不优于滑膜液细胞计数/分类加滑膜培养对膝部的PPV。
III级，诊断性研究。
