Juvenile pernicious anaemia in association with vitiligo, selective IgA deficiency, defective interleukin 12 production and T cell dysfunction

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.