Amarnani Abhimanyu, Liu Flora, Wilson Melissa Lee, Lim Nathan, Stohl William, Wise Leanna
University of Southern California Keck School of Medicine, Los Angeles, and New York University Langone Health and Bellevue Hospital Center, New York City.
University of Southern California Keck School of Medicine, Los Angeles.
ACR Open Rheumatol. 2025 Jun;7(6):e70051. doi: 10.1002/acr2.70051.
The objective of this study was to assess clinical laboratory parameters that distinguish between disease flare and infection in febrile patients with systemic lupus erythematosus (SLE) at safety-net hospitals in Los Angeles.
We reviewed electronic medical records of patients admitted from August 1, 2016, through July 31, 2019, categorizing them as disease flare, bacterial infection (culture positive), culture-negative infection, and both flare and infection. Laboratory parameters collected within 48 hours of admission (complete blood cell count with differential, liver function panel, erythrocyte sedimentation rate [ESR], C-reactive protein [CRP], C3, C4, lactate, procalcitonin, and ferritin) were analyzed.
Several laboratory parameters significantly distinguished febrile patients with disease flare from those with infection. An optimized multivariable logistic regression model revealed that an elevated ESR:CRP ratio (>1.17), low white blood cell (WBC) count (<6.25 × 10/L), low absolute neutrophil count (<5.55 × 10/L), and low CRP (<113 mg/L), C3 (<44.5 mg/dL), and C4 (<13.5 mg/dL) levels helped discriminate disease flare from culture-positive infection. These laboratory parameters yielded areas under the receiving operating characteristic curve of 0.87 (95% confidence interval [CI] 0.76-0.97) for flare versus culture-positive infection and 0.94 (95% CI 0.88-1.00) for flare versus culture-negative infection. These optimized models, using multiple laboratory parameters, significantly outperformed the ESR:CRP ratio alone (P < 0.02) in discriminating flare from infection.
The ESR:CRP ratio plus C3 and C4 levels, WBC count, neutrophil count, and monocyte count discriminate flare from either culture-positive or culture-negative infection in febrile patients with SLE. Our findings warrant prospective validation.
本研究的目的是评估洛杉矶安全网医院中发热的系统性红斑狼疮（SLE）患者疾病发作和感染之间的临床实验室参数。
我们回顾了2016年8月1日至2019年7月31日期间入院患者的电子病历，将他们分为疾病发作、细菌感染（培养阳性）、培养阴性感染以及发作和感染并存。分析入院48小时内收集的实验室参数（全血细胞计数及分类、肝功能检查、红细胞沉降率[ESR]、C反应蛋白[CRP]、C3、C4、乳酸、降钙素原和铁蛋白）。
几个实验室参数显著区分了疾病发作的发热患者和感染患者。一个优化的多变量逻辑回归模型显示，ESR:CRP比值升高（>1.17）、白细胞（WBC）计数低（<6.25×10/L）、绝对中性粒细胞计数低（<5.55×10/L）以及CRP（<113mg/L）、C3（<44.5mg/dL）和C4（<13.5mg/dL）水平低有助于区分疾病发作和培养阳性感染。这些实验室参数在区分发作与培养阳性感染时，受试者工作特征曲线下面积为0.87（95%置信区间[CI]0.76 - 0.97），在区分发作与培养阴性感染时为0.94（95%CI 0.88 - 1.00）。这些使用多个实验室参数的优化模型在区分发作和感染方面明显优于单独的ESR:CRP比值（P < 0.02）。
ESR:CRP比值加上C3和C4水平、WBC计数、中性粒细胞计数和单核细胞计数可区分发热的SLE患者的疾病发作与培养阳性或培养阴性感染。我们的发现值得进行前瞻性验证。
