Yel Leman, Liao Otto, Lin Fritz, Gupta Sudhir
Division of Basic and Clinical Immunology, Department of Medicine, University of California, Irvine, California 92697, USA.
Ann Allergy Asthma Immunol. 2003 Nov;91(5):501-5. doi: 10.1016/S1081-1206(10)61522-0.
Immunodeficiency with thymoma syndrome is a rare disorder that generally occurs after the fourth decade of life. Typically, thymic tumors are benign, and gradually developing immunodeficiency consists of hypogammaglobulinemia with low B-cell counts and an inverted CD4+/CD8+ T-cell ratio due to excessive CD8+ T cells.
To report the case of a 32-year-old, white man with an invasive malignant thymoma and profound combined T- and B-cell immunodeficiency associated with a normal CD4+/CD8+ T-cell ratio, absence of circulating B cells, and infection with an unusual organism.
The patient presented with a superior vena cava syndrome caused by a malignant thymoma. During chemotherapy and radiotherapy, he experienced recurrent episodes of pulmonary infections due to Haemophilus influenza and Serratia marcescens and persistent oral thrush. He was diagnosed as having thymoma and underwent immunological evaluation.
Sixteen months after the diagnosis of thymoma, the immunological evaluation revealed profound lymphopenia, eosinopenia, very low counts of both CD4+ T cells and CD8+ T cells, and a normal CD4+/CD8+ ratio with negative delayed-type hypersensitivity skin test results. Hypogammaglobulinemia and absent specific antibody responses were associated with a lack of peripheral blood CD19+ B cells. Despite treatment with intravenous immunoglobulin, the patient died of respiratory insufficiency and sepsis secondary to a chronic pulmonary infection.
Malignant thymoma may be associated with severe combined immunodeficiency. A normal CD4+/CD8+ ratio and the absence of peripheral B cells suggest a bone marrow defect that affects both T and B cells in the pathogenesis of this syndrome. Comprehensive immunological evaluation should be performed when thymoma is diagnosed to initiate an early and effective treatment to prevent life-threatening complications.
胸腺瘤综合征相关免疫缺陷是一种罕见疾病，通常在40岁以后发病。典型情况下，胸腺肿瘤为良性，逐渐发展的免疫缺陷包括低丙种球蛋白血症、B细胞计数低以及由于CD8⁺T细胞过多导致的CD4⁺/CD8⁺T细胞比值倒置。
报告一例32岁白人男性患者，患有侵袭性恶性胸腺瘤，伴有严重的T细胞和B细胞联合免疫缺陷，其CD4⁺/CD8⁺T细胞比值正常、循环B细胞缺失且感染了一种不常见的病原体。
患者因恶性胸腺瘤导致上腔静脉综合征就诊。在化疗和放疗期间，他因流感嗜血杆菌和粘质沙雷氏菌反复发生肺部感染，并持续患有口腔念珠菌病。他被诊断为胸腺瘤并接受了免疫学评估。
胸腺瘤诊断16个月后，免疫学评估显示严重淋巴细胞减少、嗜酸性粒细胞减少、CD4⁺T细胞和CD8⁺T细胞计数极低、CD4⁺/CD8⁺比值正常且迟发型超敏皮肤试验结果为阴性。低丙种球蛋白血症和特异性抗体反应缺失与外周血CD19⁺B细胞缺乏有关。尽管接受了静脉注射免疫球蛋白治疗，患者仍死于慢性肺部感染继发的呼吸功能不全和败血症。
恶性胸腺瘤可能与严重联合免疫缺陷有关。正常的CD4⁺/CD8⁺比值和外周B细胞缺失提示骨髓缺陷，在该综合征的发病机制中影响T细胞和B细胞。诊断胸腺瘤时应进行全面的免疫学评估，以便尽早开始有效治疗，预防危及生命的并发症。
