Division of Emergency Medicine, Boston Children's Hospital and Harvard Medical School, Boston, MA.
Department of Emergency Medicine, Children's Minnesota, Minneapolis, MN.
Ann Emerg Med. 2022 Sep;80(3):225-234. doi: 10.1016/j.annemergmed.2022.04.009. Epub 2022 May 26.
Children with a bacterial musculoskeletal infection (MSKI) require prompt identification and treatment. In Lyme disease endemic areas, children with an MSKI can present similarly to those with Lyme arthritis. Our goal was to derive a clinical prediction rule to accurately identify children at a low risk for an MSKI.
We enrolled children with monoarthritis presenting to 1 of 6 Pedi Lyme Net centers and performed a procalcitonin (PCT) and a first-tier Lyme C6 enzyme immunoassay (EIA) test. Our primary outcome was an MSKI (septic arthritis, osteomyelitis, or pyomyositis). Using recursive partitioning with k-fold cross validation, we derived a clinical prediction rule to identify children at a low risk of an MSKI. We calculated the accuracy of our novel rule in a derivation cohort.
Of the 735 children in the derivation cohort with an available research biosample, 39 (5%) had an MSKI (18 had septic arthritis, 20 had osteomyelitis, and 1 had pyomyositis), 260 (37%) had Lyme arthritis, and 436 (53%) had other inflammatory arthritis. Children with a PCT level of more than or equal to 0.50 ng/mL and those with a C-reactive protein (CRP) level of more than or equal to 0.6 mg/dL with a negative Lyme C6 EIA were classified as not low risk for an MSKI. Of the 451 (61%) children categorized as low risk, none had an MSKI (sensitivity 100%, 95% confidence interval 91.0% to 100%; specificity 74.2%, 95% confidence interval 70.5% to 77.6%).
A novel clinical decision rule that includes PCT, CRP, and a first-tier Lyme EIA was highly sensitive for MSKIs. Although broader external validation is required, the application of this rule may safely reduce invasive testing, procedures, and treatment for low risk children.
患有细菌性肌肉骨骼感染（MSKI）的儿童需要及时识别和治疗。在莱姆病流行地区，患有 MSKI 的儿童的表现可能与莱姆关节炎患者相似。我们的目标是制定一个临床预测规则，以准确识别患有 MSKI 风险较低的儿童。
我们招募了在 6 个 Pedi Lyme Net 中心就诊的单关节炎儿童，并进行降钙素原（PCT）和一线莱姆 C6 酶免疫测定（EIA）检测。我们的主要结局是 MSKI（化脓性关节炎、骨髓炎或肌脓肿）。使用递归分区和 k 折交叉验证，我们得出了一个临床预测规则来识别患有 MSKI 风险较低的儿童。我们在推导队列中计算了我们新规则的准确性。
在推导队列中，735 名有可用研究生物样本的儿童中，39 名（5%）患有 MSKI（18 名患有化脓性关节炎，20 名患有骨髓炎，1 名患有肌脓肿），260 名（37%）患有莱姆关节炎，436 名（53%）患有其他炎症性关节炎。PCT 水平大于或等于 0.50ng/ml 的儿童和 C-反应蛋白（CRP）水平大于或等于 0.6mg/dl 且莱姆 C6 EIA 阴性的儿童被归类为 MSKI 风险不高。在 451 名（61%）被归类为低风险的儿童中，没有人患有 MSKI（敏感性 100%，95%置信区间 91.0%至 100%；特异性 74.2%，95%置信区间 70.5%至 77.6%）。
一种新的临床决策规则，包括 PCT、CRP 和一线莱姆 EIA，对 MSKIs 具有高度敏感性。尽管需要更广泛的外部验证，但该规则的应用可能会安全地减少低风险儿童的侵入性检查、程序和治疗。
