We recommend that all males with KS and early sexual development or with "normal" testicular growth be screened with measurement of germ cell tumor markers including beta-subunit of human chorionic gonadotropin and alpha-fetoprotein.
The undetectable levels of serum AMH and testosterone levels indicate a lack of functional testicular tissue, for example, that in patients with anorchia or severe Klinefelter syndrome suffering from impaired spermatogenesis.
Serum AMH is low in infants with hypogonadotrophic hypogonadism (and increases with FSH treatment), in patients with primary hypogonadism from early postnatal life and in Klinefelter syndrome from midpuberty.
The relationship of genetic features of the X chromosome, including parental origin of X chromosomes, the CAG repeat length of the androgen receptor (AR) gene, and X inactivation with progression of pubertal development, growth and testicular function in KS boys.
Our findings demonstrated that the AR-qPCR technique is a simple and reliable screening method for diagnosis of patients with Klinefelter syndrome or other chromosomal disorders involving an aberrant number of X-chromosomes.
Three patients presented Klinefelter syndrome and three a partial androgen insensitivity syndrome (PAIS) as a result of p.Ala646Asp and p.Ala45Gly mutations of the androgen receptor gene.
We wanted to describe X-chromosome inactivation patterns and the AR polymorphism and correlate these to clinical findings in KS in a cross-sectional study.
The present study assessed three "classic" psychophysiological markers of psychosis in Klinefelter syndrome (KS): smooth pursuit eye movements (SPEM), prepulse inhibition (PPI) and P50 suppression.
The present study assessed three "classic" psychophysiological markers of psychosis in Klinefelter syndrome (KS): smooth pursuit eye movements (SPEM), prepulse inhibition (PPI) and P50 suppression.
Our findings thus indicate that AURKC mutations are more frequent than Klinefelter syndrome and constitute the leading genetic cause of infertility in North African men.
The percentage of microdeletions in KS patients was lower than in NOA patients, suggesting that AZF microdeletions and KS do not have a causal relationship and that Y chromosome microdeletions are not a genetic factor linked to KS.
However, in cases with negative TESE only smoking was identified as a predictive factor for negative sperm retrieval and was established as a risk factor.<b>Abbreviations:</b> AZF: azoospermia factor; BMI: body mass index; Crypt: cryptozoospermia; FSH: Follicle-Stimulating Hormone; ICSI: intracytoplasmic sperm injection; IU: international unit; KS: Klinefelter syndrome; LH: Luteinizing Hormone; mL: milliliter; NOA: non-obstructive azoospermia; OA: obstructive azoospermia; T: testosterone; TESA: testicular sperm aspiration; TESE: testicular sperm extraction.
Three proteins (Ceruloplasmin, Alpha-1-antitrypsin and Zinc-alpha-2-glycoprotein) were found to be up-regulated in samples obtained from pregnancies with Klinefelter syndrome foetuses, whereas four proteins (Apolipoprotein A-I, Plasma retinol-binding protein, Gelsolin, and Vitamin D-binding protein) were down regulated when compared to proteins detected in samples from normal foetuses.
Endocrine or syndromal disorders were diagnosed in 13 children (<1%; 4 with hypothyroidism, 1 with Cushing's syndrome, 1 with growth hormone deficiency, 2 with pseudohypoparathyroidism, 1 with pseudopseudohypoparathyroidism, 2 with Prader-Willi syndrome, 1 with Bardet-Biedl syndrome, 1 with Klinefelter syndrome).
When non-KS oligo-azoospermic patients were classified according to histology [Sertoli cell-only (SCO), n = 18 or non-Sertoli cell only (non-SCO), n= 18] and compared to KS patients, the hormonal pattern did not differ between SCO and non-SCO subjects, but levels in KS patients were significantly different for FSH, inhibin-B and the FSH/inhibin-B ratio.
Serum FSH levels were elevated (21.7 IU/l) compared to normal age-matched healthy male controls and patients with non-mosaic Klinefelter syndrome, and inhibin B levels were low-normal, in contrast to the usually undetectable inhibin B levels in adult Klinefelter patients.