<p>Update On The Clinical Perspectives And Care Of The Child With 47,XXY (Klinefelter Syndrome)</p>

Abstract

Abstract47,XXY (Klinefelter syndrome [KS]) is the most common sex chromosomal aneuploidy (1:660), yet, despite this, only 25% of the males are ever diagnosed. Males with 47,XXY present with characteristic symptoms throughout their lifetime with typical physical and neurodevelopmental manifestations focused in growth, cognitive development, endocrine function, and reproduction. Studies have demonstrated that optimal outcomes are dependent on early detection combined with consistent and targeted neurodevelopmental treatment throughout the lifespan. During infancy and into the preschool years, individuals with 47,XXY commonly face deficits in growth and development in the areas of early hormonal, motor, speech, and behavioral development. As they transition into school, the primary neurodevelopmental concerns include language difficulty, executive dysfunction, behavior, and learning and reading deficits. Adults with 47,XXY often present with taller than average height, low levels of fertility, azoospermia, and elevated gonadotropin levels. These presentations may persist from early childhood through adulthood but can be mitigated by appropriate interventions. Early neurodevelopmental and hormonal treatment has been shown to have a minimizing effect on the physical and neurodevelopmental manifestations in individuals with 47,XXY. With innovative and current research studies, the features common to the neurodevelopmental profile of 47,XXY have been further expanded and defined. Further research is necessary to elucidate and understand the relationship between the brain, behavior, and the phenotypic profile of 47,XXY.

Noninvasive prenatal testing for assessing foetal sex chromosome aneuploidy: a retrospective study of 45,773 cases

“…The inclusion criteria were as follows: [ 1 ] gestational week between 12 +0 ~26 +6 and [ 2 ] singleton pregnancy. The exclusion criteria were as follows: [ 1 ] gestational age < 12 weeks; [ 2 ] multiple pregnancies; [ 3 ] definite chromosomal abnormalities; [ 4 ] pregnant women who underwent an allogeneic blood transfusion, stem cell therapy, transplant surgery, or other procedure; [ 5 ] a family history of genetic disease or an indication for a high risk of genetic disease in the foetus; [ 6 ] pregnant women with malignant tumours; and [ 7 ] other conditions that might affect the accuracy of the results.…”

“…In adults, the extra X chromosome may affect testicular development, which will result in infertility and hypogonadotropic hypogonadism [ 6 ]. Males with 47,XXY also have a higher risk of learning disabilities, developmental delays, cardiometabolic disease, typical physical symptoms and neurodevelopmental manifestations [ 6 , 7 ]. 47,XYY occurs in 1 in 1000 males [ 8 ], and these males tend to have tall stature, face social obstacles, have behavioural problems, and exhibit language impairment.…”

“…The phenotypes of SCA patients include a broad range of associated symptoms that vary in severity, depending on the timing of diagnosis and type of SCA [ 4 , 5 , 7 – 9 ]. The frequency of SCA is estimated to be 1 in every 500 live births.…”

Non-invasive Prenatal Testing for Assessing Fetal Sex Chromosome Aneuploidy: A Retrospective Study of 45773 Cases

“…When they come to adults, the extra X chromosome may affect testicular development which will result in infertility and hypogonadotropic hypogonadism [6] . The males with 47,XXY also have a higher risk of learning disabilities, developmental delays, cardiometabolic disease, typical physical symptoms and neurodevelopmental manifestations [6,7] . 47,XYY occurs in 1 in 1000 males [8] who tend to have tall stature, social obstacles, behavioral problems, and language impairment.…”

“…The phenotype of SCA patients spans a broad range of associated symptoms that vary in severity, depending on the timing of diagnosis and types of SCA [4,5,7,8,9] . The frequency of SCA is estimated to be 1 in every 500 live births.…”