Division of Pulmonary Medicine, Texas Children's Hospital, Houston, Texas, USA.
Department of Pediatrics, Baylor College of Medicine, Houston, Texas, USA.
Pediatr Pulmonol. 2021 Jan;56(1):145-152. doi: 10.1002/ppul.25151. Epub 2020 Nov 9.
To investigate pulmonary histopathologic features in a cohort of pediatric patients with anti-neutrophil cytoplasmic antibody (ANCA)-associated vasculitis (AAV) who underwent a lung biopsy as part of their evaluation. We report the safety and the findings of lung biopsies in this population.
After IRB approval, we performed a retrospective chart review of all patients <18 years of age presenting to our institution with a diagnosis of pediatric AAV (pAAV) who underwent lung biopsy. We reviewed histopathologic features, serologies, the timing of biopsy, and complications.
Fourteen patients met inclusion criteria, nine patients with microscopic polyangiitis (MPA), and five patients with granulomatosis with polyangiitis (GPA). All patients had positive ANCA serology. 13/14 patients required admission on initial presentation for respiratory symptoms; 11/13 required respiratory support. The indication for biopsy was confirmation of diagnosis before initiating therapy in 11 patients (78%), part of the infectious evaluation in two (14%), and part of interstitial lung disease evaluation in one (7%). 11/14 (78%) biopsies had findings consistent with AAV diagnosis: 6/9 (67%) of the MPA patients compared with 5/5 (100%) of the GPA patients. The most common findings on histopathology were vascular inflammation and signs of alveolar hemorrhage. The only reported complication after lung biopsy was pneumothorax in four patients (28%).
Lung biopsy had a higher diagnostic yield in GPA compared with MPA patients. In our cohort, a diagnosis of AAV could be made with clinical features and positive serology but was confirmed by lung histopathology in the majority of cases. Obtaining a lung biopsy for diagnostic purposes in pAAV should be reserved for uncertain cases where the diagnosis cannot be confirmed clinically and with serology.
研究作为评估一部分接受肺活检的抗中性粒细胞胞浆抗体（ANCA）相关性血管炎（AAV）儿科患者队列的肺组织病理学特征。我们报告该人群中肺活检的安全性和结果。
在获得机构审查委员会批准后，我们对我院所有<18 岁的诊断为儿童 AAV（pAAV）并接受肺活检的患者进行了回顾性病历审查。我们回顾了组织病理学特征、血清学、活检时机和并发症。
14 名患者符合纳入标准，9 名患有显微镜下多血管炎（MPA），5 名患有肉芽肿性多血管炎（GPA）。所有患者的 ANCA 血清学均为阳性。14 例患者中，13 例在初次出现呼吸道症状时需要入院治疗；13 例中有 11 例需要呼吸支持。活检的指征是在开始治疗前确认诊断，11 例患者中有 11 例（78%）；2 例患者作为感染评估的一部分，2 例患者作为间质性肺病评估的一部分。11/14（78%）的活检结果与 AAV 诊断一致：6/9（67%）的 MPA 患者与 5/5（100%）的 GPA 患者。组织病理学上最常见的发现是血管炎症和肺泡出血的迹象。肺活检后唯一报告的并发症是 4 例患者（28%）气胸。
肺活检在 GPA 患者中的诊断率高于 MPA 患者。在我们的队列中，AAV 的诊断可以通过临床特征和阳性血清学做出，但在大多数情况下通过肺组织病理学得到证实。在 pAAV 中，为了明确诊断而进行肺活检应保留给无法通过临床和血清学确认的不确定病例。
