[Application of fluorescence in situ hybridization combined with chromosomal karyotyping analysis in children with disorders of sex development due to sex chromosome abnormalities].

Objective: To retrospectively analyze sex chromosomal abnormalities and clinical manifestations of children with disorders of sex development (DSD).

Methods: A total of 14 857 children with clinical features of DSD including short stature, cryptorchidism, hypospadia, buried penis and developmental delay were recruited from Zhengzhou Children's Hospital from January 2013 to March 2022. Fluorescence in situ hybridization (FISH) and chromosomal karyotyping were carried out for such children.

Results: In total 423 children were found to harbor sex chromosome abnormalities, which has yielded a detection rate of 2.85%. There were 327 cases (77.30%) with Turner syndrome and a 45,X karyotype or its mosaicism. Among these, 325 were females with short stature as the main clinical manifestation, 2 were males with short stature, cryptorchidism and hypospadia as the main manifestations. Sixty-two children (14.66%) had a 47,XXY karyotype or its mosaicism, and showed characteristics of Klinefelter syndrome (KS) including cryptorchidism, buried penis and hypospadia. Nineteen cases (4.49%) had sex chromosome mosaicisms (XO/XY), which included 11 females with short stature, 8 males with hypospadia, and 6 cases with cryptorchidism, buried penis, testicular torsion and hypospadia. The remainder 15 cases (3.55%) included 9 children with a XYY karyotype or mosaicisms, with main clinical manifestations including cryptorchidisms and hypospadia, 4 children with a 47,XXX karyotype and clinical manifestations including short stature and labial adhesion, 1 child with a 46,XX/46,XY karyotype and clinical manifestations including micropenis, hypospadia, syndactyly and polydactyly, and 1 case with XXXX syndrome and clinical manifestations including growth retardation.

Conclusion: Among children with DSD due to sex chromosomal abnormalities, sex chromosome characteristics consistent with Turner syndrome was most common, among which mosaicism (XO/XX) was the commonest. In terms of clinical manifestations, the females mainly featured short stature, while males mainly featured external genital abnormalities. Early diagnosis and treatment are particularly important for improving the quality of life in such children.