Augustine Antony, Robinson Vimala Leena, Irodi Aparna, Mathew John, Pakkal Mini
Department of Radiodiagnosis, Christian Medical College and Hospital, Vellore, Tamil Nadu, India.
Department of Clinical Immunology and Rheumatology, Christian Medical College and Hospital, Vellore, Tamil Nadu, India.
Indian J Radiol Imaging. 2022 Dec 26;33(1):70-75. doi: 10.1055/s-0042-1758876. eCollection 2023 Jan.
Usual interstitial pneumonia (UIP) pattern of interstitial lung disease (ILD) can have varied etiology, with connective tissue disease (CTD) being a common known cause. The anterior upper lobe (AUL) sign, exuberant honeycombing (EHC), and straight edge (SE) sign are recently described computed tomography (CT) signs in CTD-related UIP. We test the diagnostic value of these CT signs for CTD in patients with UIP and compare the incidence of these signs between CTD-related UIP and non-CTD-related UIP. We also evaluated the interobserver agreement in detection of these CT signs. Retrospective study of all patients who had UIP pattern of ILD on CT thorax done from January 1, 2016 to January 31, 2019, was grouped into two: non-CTD-related UIP or CTD-related UIP. CT thorax was reviewed for the presence of these signs-AUL, SE, and EHC. The diagnostic values of these signs in diagnosing CTD-related UIP was assessed. For assessment of interobserver agreement, another radiologist reviewed a subset of 30 randomly selected cases and looked for the presence of these signs. Of the 156 patients included, 76 had CTD. The incidence of CT signs were significantly higher in CTD-related UIP. The specificities of AUL, EHC, and SE were 82.5, 75, and 85%, respectively. The EHC sign had highest sensitivity of 48.7%. Inclusion of more than one sign increased the specificity of diagnosis of CTD-related UIP; however, the sensitivity decreases. There was excellent interobserver agreement (0.81-0.87) for each of these signs. The presence of SE, AUL, and EHC signs in cases with UIP pattern are specific imaging markers to diagnose underlying CTD; however, due to its low sensitivity, the absence of these signs cannot exclude the same. Because of its excellent interobserver agreement, these signs are reliable in the evaluation of CTD-related ILD.
间质性肺疾病（ILD）的普通型间质性肺炎（UIP）模式病因多样，结缔组织病（CTD）是常见的已知病因。前上叶（AUL）征、显著蜂窝状改变（EHC）和直边（SE）征是最近在CTD相关UIP中描述的计算机断层扫描（CT）征象。我们测试这些CT征象对UIP患者CTD的诊断价值，并比较CTD相关UIP和非CTD相关UIP中这些征象的发生率。我们还评估了观察者之间对这些CT征象检测的一致性。 对2016年1月1日至2019年1月31日期间胸部CT表现为ILD的UIP模式的所有患者进行回顾性研究，分为两组：非CTD相关UIP或CTD相关UIP。对胸部CT进行复查，以确定这些征象——AUL、SE和EHC是否存在。评估这些征象在诊断CTD相关UIP中的诊断价值。为评估观察者之间的一致性，另一位放射科医生复查了30例随机选择的病例子集，并寻找这些征象的存在情况。 在纳入的156例患者中，76例患有CTD。CT征象的发生率在CTD相关UIP中显著更高。AUL、EHC和SE的特异性分别为82.5%、75%和85%。EHC征的敏感性最高，为48.7%。纳入多个征象可提高CTD相关UIP诊断的特异性；然而，敏感性会降低。这些征象中的每一个都有极好的观察者间一致性（0.81 - 0.87）。 UIP模式病例中SE、AUL和EHC征的存在是诊断潜在CTD的特异性影像标志物；然而，由于其敏感性较低，这些征象的不存在不能排除CTD。由于其极好的观察者间一致性，这些征象在评估CTD相关ILD时是可靠的。
