MHk Ho, GCF Chan, BM Jones, TL Lee, AKS Chiang, SY Ha, YL Lau

Abstract

The coexistence of juvenile pernicious anaemia, vitiligo and selective IgA deficiency in a Southern Chinese boy stimulated a comprehensive work-up of his immune functions. He was found to have an imbalance of T-helper cell (CD4+) and T-suppressor cell (CD8+) activity, leading to low B cell response in vitro to pokeweed-mitogen in production of IgA. Interleukin 12 production in response to various mitogens was also deficient. These abnormalities persisted despite effective vitamin B12 treatment. We speculate that the defective immunoregulatory environment is an intrinsic defect rather than an acquired phenomenon due to vitamin B12 deficiency, which may play an important role in the pathogenesis of juvenile pernicious anaemia.

1 例中國南方男孩同時患有少年惡性貧血、白癜風及選擇性 IgA 缺乏激發其廣泛的免疫功能紊亂。該患兒存在 T 輔助細胞（CD4+）與 T 抑制細胞（CD8+）活性失平衡，導致體內 B 細胞對 IgA 產物中絲狀原素（pokeweed-mitogen）反應低下，對各種絲狀原素（mitogen）反應產生白細胞介素 12 也缺乏。儘管用有效的維生素 B12 治療，上述異常仍然存在。我們推測這種免疫調節環境的缺陷是一種內在的缺陷，而不是由於維生素 B12 缺乏所致的繼發現象，這種內在缺陷在少年惡性貧血的發病機制中起重要作用。