隱源性器質化肺炎（Cryptogenic organizing pneumonia）：疾病之診斷、影像學特徵與治療反應預測因子之探討

Cryptogenic Organizing Pneumonia: Diagnostic Criteria, Image Pattern and Predictors of Treatment Response and Relapse

吳育丞(Yu-Cheng Wu) ； 傅彬貴(Pin-Kuei Fu)

《內科學誌》 33卷3期 (2022/06) Pp. 178-189

https://doi.org/10.6314/JIMT.202206_33(3).02

摘要

隱源性器質化肺炎（Cryptogenic organizing pneumonia; COP）是一種不明原因所致的間質性肺病，典型症狀為類上呼吸道感染症狀如咳嗽、發燒、全身無力等。在診斷上，胸部X光、肺泡灌流液以及高解析度電腦斷層（High-resolution computed tomography; HRCT）肺部影像學檢查都是可以使用的工具。COP在HRCT之典型與非典型表現：典型表現為多發性肺泡狀浸潤；非典型的影像表現如結節狀（NODULAR pattern）、小葉旁特徵（PERILOBULAR pattern）、不規則石板拼鋪型態（CRAZY-paving pattern）、進展性纖維化（Progressive fibrosis COP）、反轉型月暈特徵（REVERSED halo sign，或稱為Atoll sign）以及線性和帶狀不透明度（Linear and band-like opacities）等。COP的診斷以組織病理切片出現馬松氏小體（Masson's bodies）特徵而確診。在治療上，全身性肺類固醇如Methylprednisolone或Prednisone 0.5～1毫克／公斤／天，是治療首選，建議使用6-12個月。其他替代藥物如Macrolides以及cyclophosphamide等。雖然COP對類固醇治療反應頗佳，但停用類固醇之後容易再復發的因素有：肺部實質化＞10%、合併支氣管擴張症、肺泡液出現高比例中性球、病理組織出現纖維沉積、HRCT出現進行性纖維化型態以及小葉旁特徵等。另外也需再次評估是否合併自體免疫疾病。容易殘存肺部病灶的因素有：肺實質化面積＞10%、合併支氣管擴張症以及大量纖維沉積於肺泡等。除此之外，也要考慮原先診斷的COP是否合併IPF急性發作、或者其實是尚未被診斷的自體免疫疾病所造成的器質化肺炎（CTD-OP）。

關鍵字

隱源性器質化肺炎（Cryptogenic organizing pneumonia ； COP） ； 高解析度電腦斷層（HRCT） ； 預後因子（Predictive factor） ； 復發（Relapse） ； 殘存肺部病變（Residual lung disease）

並列摘要

Cryptogenic organizing pneumonia (COP) is an interstitial lung disease of unknown etiology. It has a heterogeneous clinical course, typically beginning with symptoms of cough, fever, and general weakness. Chest X ray, bronchoalveolar lavage (BAL) and High-Resolution Computed Tomography (HRCT) are useful tools for its diagnosis. Image findings of COP in HRCT are either typical or atypical patterns. The typical pattern shows multiple alveolar opacities. The atypical pattern appears in a variety of forms, like nodular pattern, perilobular pattern, crazy-paving pattern, progressive fibrosis pattern, reversed halo sign (or Atoll sign) and linear and band-like opacities. The key finding for COP diagnosis is the presence of the ＂Masson's bodies＂ in tissue biopsy. The first line COP treatment is systemic steroid (methylprednisolone or prednisone 0.5 to 1 mg/kg/day) used continuously for 6 to 12 months. Other medications of choice are macrolides or cyclophosphamide. Most patients respond well to steroids, but ~1/3 of them have the COP recurred. Predictive factors of relapsing after stopping the steroid treatment are consolidation involving ＞10% of parenchyma, detectable bronchiectasis, high neutrophil percentages in BAL, high levels of fibrin deposition in lung biopsy, progressive fibrosis and perilobular pattern in HRCT. Subtle connective tissue disease-organizing +pneumonia (CTD-OP) should also be evaluated at this time. The predictive factors of residual lung disease in COP are consolidation involving ＞10% of parenchyma, detectable bronchiectasis, high levels of fibrin deposition in lung biopsy, co-existence with acute exacerbation of idiopathic pulmonary fibrosis or undiagnosed CTD-OP.