■由于被称为假蜂窝织炎的模拟条件,在多达30%的病例中,蜂窝织炎被误诊。抗生素的过度使用对患者安全和公共健康构成威胁。表面热成像和ALT-70(不对称,白细胞增多,心动过速,和年龄≥70岁)的预测模型已被提出作为帮助区分蜂窝织炎和假蜂窝织炎的工具。
为了验证蜂窝织炎患者和假性蜂窝织炎患者皮肤表面温度的差异,评估区分蜂窝织炎和假蜂窝织炎的最佳温度测量和切点,并比较皮肤表面温度和ALT-70预测模型在区分蜂窝织炎和假蜂窝织炎中的性能。
这项前瞻性诊断验证研究是在2018年10月11日至2020年3月11日期间因急性皮肤病性下肢症状就诊于急诊科的患者中进行的。2020年7月至2021年3月进行了统计分析,2023年9月进行了额外工作。
■获得受影响和未受影响的皮肤的温度测量值。蜂窝织炎与假蜂窝织炎由6名医生评估,独立共识审查。使用t检验比较温度测量值的差异。使用逻辑回归来确定温度测量值和相关的切点,以最佳性能区分蜂窝织炎和假蜂窝织炎。ALT-70预测模型的诊断性能特征,表面皮肤温度,两者的结合也进行了评估。
■最终样本包括204名参与者(平均[SD]年龄,56.6[16.5]岁;121名男性[59.3%]),92人(45.1%)有一致的蜂窝织炎诊断。所有皮肤表面温度测量值均存在统计学上的显着差异(平均温度,最高温度,和梯度)在蜂窝织炎和假蜂窝织炎之间。蜂窝织炎患者的患肢最高温度为33.2°C,而假性蜂窝织炎患者的患肢最高温度为31.2°C(差异,2.0°C[95%CI,1.3-2.7°C];P<.001)。最高温度是受影响皮肤的最佳温度测量,切点为31.2°C,平均(SD)阴性预测值为93.5%(4.7%),敏感性为96.8%(2.3%)。3项措施的敏感度均保持在90%以上,而特异性差异很大(ALT-70,22.0%[95%CI,15.8%-28.1%];患肢的最高温度,38.4%[95%CI,31.7%-45.1%];组合测量,53.9%[95%CI,46.5%-61.2%])。
■在这项大型诊断验证研究中,在蜂窝织炎病例和假蜂窝织炎病例之间观察到皮肤表面温度测量的显著差异。热成像和ALT-70都显示出高灵敏度,但通过结合这两种措施,特异性得到了改善。这些发现支持了热成像的潜力,单独或与ALT-70预测模型相结合,作为诊断辅助手段,可以减少蜂窝织炎的过度诊断。
UNASSIGNED: Cellulitis is misdiagnosed in up to 30% of cases due to mimic conditions termed pseudocellulitis. The resulting overuse of antibiotics is a threat to patient safety and public health. Surface thermal imaging and the ALT-70 (asymmetry,
leukocytosis, tachycardia, and age ≥70 years) prediction model have been proposed as tools to help differentiate cellulitis from pseudocellulitis.
UNASSIGNED: To validate differences in skin surface temperatures between patients with cellulitis and patients with pseudocellulitis, assess the optimal temperature measure and cut point for differentiating cellulitis from pseudocellulitis, and compare the performance of skin surface temperature and the ALT-70 prediction model in differentiating cellulitis from pseudocellulitis.
UNASSIGNED: This prospective diagnostic validation study was conducted among patients who presented to the emergency department with acute dermatologic lower extremity symptoms from October 11, 2018, through March 11, 2020. Statistical analysis was performed from July 2020 to March 2021 with additional work conducted in September 2023.
UNASSIGNED: Temperature measures for affected and unaffected skin were obtained. Cellulitis vs pseudocellulitis was assessed by a 6-physician, independent consensus review. Differences in temperature measures were compared using the t test. Logistic regression was used to identify the temperature measure and associated cut point with the optimal performance for discriminating between cellulitis and pseudocellulitis. Diagnostic performance characteristics for the ALT-70 prediction model, surface skin temperature, and both combined were also assessed.
UNASSIGNED: The final sample included 204 participants (mean [SD] age, 56.6 [16.5] years; 121 men [59.3%]), 92 (45.1%) of whom had a consensus diagnosis of cellulitis. There were statistically significant differences in all skin surface temperature measures (mean temperature, maximum temperature, and gradients) between cellulitis and pseudocellulitis. The maximum temperature of the affected limb for patients with cellulitis was 33.2 °C compared with 31.2 °C for those with pseudocellulitis (difference, 2.0 °C [95% CI, 1.3-2.7 °C]; P < .001). The maximum temperature was the optimal temperature measure with a cut point of 31.2 °C in the affected skin, yielding a mean (SD) negative predictive value of 93.5% (4.7%) and a sensitivity of 96.8% (2.3%). The sensitivity of all 3 measures remained above 90%, while specificity varied considerably (ALT-70, 22.0% [95% CI, 15.8%-28.1%]; maximum temperature of the affected limb, 38.4% [95% CI, 31.7%-45.1%]; combination measure, 53.9% [95% CI, 46.5%-61.2%]).
UNASSIGNED: In this large diagnostic validation study, significant differences in skin surface temperature measures were observed between cases of cellulitis and cases of pseudocellulitis. Thermal imaging and the ALT-70 both demonstrated high sensitivity, but specificity was improved by combining the 2 measures. These findings support the potential of thermal imaging, alone or in combination with the ALT-70 prediction model, as a diagnostic adjunct that may reduce overdiagnosis of cellulitis.