Adam Z, Elleder M, Moulis M, Tichý M, Cervinková I, Rehák Z, Koukalová R, Fojtík Z, Hanke I, Pour L, Krejčí M, Zahradová L, Szturz P, Hájek R, Král Z, Mayer J
Interní Hematoonkologická Klinika Lékarské Fakulty MU a Brno, Pracovisté Bohunice, Prednosta prof. MUDr. Jirí Mayer, CSc.
Vnitr Lek. 2012 Mar;58(3):241-52.
Depending on the extent of organism affected, there is a systemic (amyloid is deposited in the interstitial space of multiple tissues and organs) and localized (amyloid is deposited in one or a few solitary lesions) form of amyloidosis. Localized forms of amyloidosis have a significantly better prognosis than the systemic ones. The respiratory tract might be affected by diffuse interstitial involvement, associated with systemic AL-amyloidosis, as well as localised involvement of respiratory tract (localised laryngotracheobronchial amyloidosis) or pulmonary parenchyma called nodular form of localized pulmonary amyloidosis. Tracheobronchial form may affect larynx and bronchial tree, and forms plaques or nodules in the epithelium of the respiratory tract. Nodular form causes spherical or irregular lesions in the pulmonary parenchyma, indistinguishable from pulmonary parenchyma metastases. We describe a two-year follow up of a patient with nodular form of pulmonary amyloidosis. The patient had multiple lesions in both lungs, clearly visible on HRCT (High Resolution Computer Tomography) that intensively accumulated fluorodeoxyglucose (FDG) during the first PET-CT. At the time of diagnosis, the largest lesion SUV for FDG accumulation was 8.2. Histochemical analysis showed that amyloid consisted of the light λ chains, i.e. AL-amyloid. Investigations to detect a systemic form of amyloidosis, if present, were negative. The patient had no monoclonal immunoglobulin either in the urine or serum (negative immunofixation) and had normal levels of free light chains in the serum. Her symptoms were previously suggestive of the Sjögrens syndrome. However, the rheumatologist consulted at the time of diagnosis of the nodular form of pulmonary amyloidosis did not find any signs of an active systemic connective tissue disorder. CRP was repeatedly normal. When systemic AL-amyloidosis was excluded, we decided to only monitor lesion development with no treatment intervention. The patient had 3 PET-CTs. CT showed that no lesions enlarged, some lesions decreased in size slightly. It should be emphasized that follow-up PET-CTs did not show increased FDG accumulation. We assume that the increased FDG accumulation in pulmonary lesions seen during the first PET-CT was due to the activity of the cells that formed this amyloid and that this activity spontaneously ceased, leading to normalization of FDG accumulation in pulmonary nodules. PET-CT is useful for monitoring of the development of pulmonary nodular amyloidosis. Normalization of originally increased FDG accumulation in amyloid lesions suggests cessation of the process of amyloid formation and is a positive prognostic sign.
根据受影响机体的范围，淀粉样变性有全身性（淀粉样物质沉积于多个组织和器官的间质间隙）和局限性（淀粉样物质沉积于一个或几个孤立性病变）两种形式。局限性淀粉样变性的预后明显好于全身性淀粉样变性。呼吸道可能会受到弥漫性间质受累的影响，这与全身性AL淀粉样变性有关，也可能受到呼吸道局部受累（局限性喉气管支气管淀粉样变性）或肺实质受累（局限性肺淀粉样变性的结节型）的影响。气管支气管型可累及喉部和支气管树，并在呼吸道上皮形成斑块或结节。结节型在肺实质内形成球形或不规则病变，与肺实质转移瘤难以区分。我们描述了一名局限性肺淀粉样变性结节型患者的两年随访情况。该患者双肺有多个病变，在高分辨率计算机断层扫描（HRCT）上清晰可见，在首次正电子发射断层扫描-计算机断层扫描（PET-CT）期间强烈摄取氟脱氧葡萄糖（FDG）。诊断时，最大病变的FDG摄取SUV为8.2。组织化学分析显示淀粉样物质由轻链λ组成，即AL淀粉样物质。检测全身性淀粉样变性（如果存在）的检查结果为阴性。患者尿液和血清中均无单克隆免疫球蛋白（免疫固定阴性），血清游离轻链水平正常。她的症状以前提示干燥综合征。然而，在诊断局限性肺淀粉样变性结节型时咨询的风湿病学家未发现任何活动性全身性结缔组织病的迹象。C反应蛋白（CRP）多次正常。排除全身性AL淀粉样变性后，我们决定仅监测病变发展情况，不进行治疗干预。该患者进行了3次PET-CT检查。CT显示没有病变增大，一些病变略有缩小。应该强调的是，后续的PET-CT检查未显示FDG摄取增加。我们推测首次PET-CT检查时在肺部病变中看到的FDG摄取增加是由于形成这种淀粉样物质的细胞的活性，并且这种活性自发停止，导致肺结节中FDG摄取正常化。PET-CT有助于监测局限性肺淀粉样变性的发展。淀粉样病变中最初增加的FDG摄取正常化表明淀粉样物质形成过程停止，是一个积极的预后标志。
