RESUMO
Objective To analyze the clinical and molecular genetic characterizations of X-linked adrenal dysplasia congenita(AHC) onset in infant.Methods Seven children (from 7 families) with X-linked AHC who were admitted to the Department of Endocrinology,Genetics and Metabolism,Children's Hospital Affiliated to Zhengzhou University,from July 2012 to June 2017 were selected.All patients were screened for dosage-sensitive-sex reversal-adrenal hypoplasia congenital critical region on the X chromosome gene1 (DAX1/NR0B1) mutations.The clinical manifestation and laboratory examination were analyzed,their clinical characterizations were summarized.Results Seven patients were all male,the onset age of the patients were from after birth to 7 months old,and 4 patients (4 families) had a family history of X-linked recessive inheritance.The clinical manifestations were skin pigmentation [100.0％ (7/7 cases)],vomiting [71.4％ (5/7 cases)],no weight gain [57.1％ (4/7 cases)] and poor spirit [28.6％ (2/7 cases)].Laboratory tests showed that hyperkalemia and hyponatremia,increased coricotrophin,normal or decreased cortisol,17α-hydroxyprogesterone,progesterone,aldosterone and dehydroepiandrosterone.Testosterone levels increased in 5 patients.The abnormalities of adrenal glands imaging could be seen in 2 patients.Two patients were misdiagnosed as congenital adrenal cortical hyperplasia.Then the definitive diagnosis were made by genetic test.DAX1/ NR0B1 gene mutations were found in all patients.Five patients were novel mutations (c.114_126del,c.872G ＞ A,c.56delG,c.884T ＞ G,c.1217delG).Conclusions The clinical manifestations of X-linked AHC with infant onset include pigmentation,poor spirit and growth retardation,which should be differentiated from congenital adrenal cortical hyperplasia.Hormone levels such as elevated blood 17α-hydroxyprogesterone and family history are the main identification points,and AHC cannot be excluded when testosterone level increases.Five novel mutations are found in this study,which enrich the gene database.