Vanderbilt University Medical Center, Nashville, Tennessee.
Tennessee Valley VA Healthcare System, Nashville, Tennessee.
Cancer Epidemiol Biomarkers Prev. 2019 Feb;28(2):321-326. doi: 10.1158/1055-9965.EPI-18-0169. Epub 2018 Oct 19.
Granulomas caused by infectious lung diseases present as indeterminate pulmonary nodules (IPNs) on radiography. Newly available serum enzyme immunoassay (EIA) for histoplasmosis has not been studied for the evaluation of IPNs. We investigated serum biomarkers of histoplasmosis antibodies as an indication of benign disease in IPNs from a highly endemic region.
A total of 152 serum samples from patients presenting with pulmonary nodules ≤30 mm in maximum diameter were analyzed for histoplasmosis antibodies by immunodiffusion and EIA IgG and IgM tests. Serology and FDG-PET/CT scan diagnostic test characteristics were estimated and compared.
Cancer prevalence was 55% ( = 83). Thirty-nine (26%) individuals were positive for IgG histoplasmosis antibodies. Twelve samples were IgM antibody positive. Immunodiffusion serology was similar to IgM antibody results with 13 positive tests. Diagnostic likelihood ratios for benign disease were 0.62, 0.33, and 0.28 for FDG-PET/CT, IgG, and IgM antibodies, respectively. When both IgG and IgM were positive ( = 8), no nodules were cancerous and six were FDG-PET/CT avid.
A positive EIA test for both IgM and IgG strongly suggested histoplasmosis etiology and benign granuloma for 12% of benign nodules arising from a highly endemic region. Presence of either IgG or IgM histoplasma antibodies was associated with benign disease. The EIA test was more sensitive in assessing histoplasma exposure than immunodiffusion serology.
A new CLIA-certified histoplasmosis antibody EIA test measures histoplasmosis exposure, offers a possible alternative clinical diagnosis for benign IPNs, and may improve IPN evaluation while avoiding harmful invasive biopsies.
由传染性肺部疾病引起的肉芽肿在放射学上表现为不定型肺结节（IPN）。新型血清酶免疫分析（EIA）技术尚未被用于评估 IPN。我们研究了组织胞浆菌病的血清生物标志物，以作为来自高流行地区 IPN 良性疾病的指标。
共分析了 152 例最大直径≤30mm 的肺结节患者的血清样本，通过免疫扩散和 EIA IgG 和 IgM 试验检测组织胞浆菌病抗体。评估并比较了血清学和 FDG-PET/CT 扫描的诊断测试特征。
癌症患病率为 55%（=83）。39 例（26%）患者 IgG 组织胞浆菌抗体阳性。12 例血清 IgM 抗体阳性。免疫扩散血清学与 IgM 抗体结果相似，有 13 例阳性检测。良性疾病的诊断似然比分别为 FDG-PET/CT、IgG 和 IgM 抗体的 0.62、0.33 和 0.28。当 IgG 和 IgM 均为阳性（=8）时，没有结节为癌症，6 个结节 FDG-PET/CT 代谢活跃。
在来自高流行地区的 12%良性结节中，EIA 检测同时检测到 IgM 和 IgG 呈阳性强烈提示组织胞浆菌病病因和良性肉芽肿。存在 IgG 或 IgM 组织胞浆菌抗体与良性疾病相关。EIA 试验比免疫扩散血清学更能敏感地评估组织胞浆菌暴露。
一种新的 CLIA 认证的组织胞浆菌抗体 EIA 试验可检测组织胞浆菌暴露，为良性 IPN 提供可能的替代临床诊断，并可能改善 IPN 评估，同时避免不必要的侵入性活检。
