Distribution, clinical features and molecular analysis of primary immunodeficiency diseases in Chinese children: a single-center study from 2005 to 2011

METHODS

Two hundred three children with genetically proven primary immunodeficiency diseases (PIDs) from 197 unrelated families were enrolled from January 2005 to December 2011.

RESULTS

On the basis of criteria developed by the International Union of Immunological Societies, 79 patients were diagnosed as "other well-defined immunodeficiency syndromes" (38.9%), 62 (30.6%) with "predominant antibody deficiencies," 26 (12.8%) with "congenital defects of phagocyte," 25 (12.3%) with "T- and B-cell immunodeficiency" and 11 (5.4%) with "diseases of immune dysregulation." The median time to the diagnosis was 27.9 months and the patients had a wide range of clinical presentations. In addition, a total of 23 pathogenic genes were identified and 213 mutations were detected, including 42 novel mutations.

CONCLUSIONS

With the increase in the awareness of PIDs and diagnostic competence, more PID patients will be diagnosed and we will be able to more accurately identify the frequency and the distribution of PIDs in the most populous country in the world.

[Common variable immunodeficiency: an update on etiology, pathophysiology, and classification]

Common variable immunodeficiency is one of the most common primary immunodeficiency that is categorized into primary antibody deficiency. The responsible genes identified so far include ICOS, TACI, CD19, CD20, CD21, CD81 and BAFF-R; and most of the CVID-causing genes are yet to be identified. TACI mutation is the most common one; however the direct contribution of TACI mutation to pathogenesis of CVID is not yet clear. One third to a half of the patients with CVID shows autoimmunity as well as malignancy in their course. It is of importance to develop diagnostic measure, to identify the disease causing genes, and to develop the optimal therapy.