OBJECTIVE: To investigate the detection patterns, clinical phenotypic characteristics, and differences in diagnostic timeliness of Klinefelter syndrome (KS) across prenatal and postnatal stages, with an aim to provide a basis for optimizing strategies for early screening, diagnosis, and intervention. METHODS: A retrospective study was conducted to analyze data from two phases. The prenatal diagnosis group included 33,302 pregnant women who underwent amniocytic karyotyping due to advanced maternal age, abnormal ultrasound findings, or high-risk non-invasive prenatal testing (NIPT). The postnatal diagnosis group included 52,101 patients who underwent peripheral blood karyotyping due to primary infertility, abnormal external genitalia, or growth and developmental abnormalities. Additionally, medical histories of adult diagnosed patients were reviewed retrospectively to identify early occult symptoms. This study was approved by the Medical Ethics Committee of Chengdu Women's and Children's Central Hospital (Ethics No.: LCYJ-2025-030). RESULTS: In the prenatal group, 96 cases of KS were detected (detection rate 0.29%). The primary indications for referral were NIPT indicating sex chromosome abnormalities (45.83%), advanced maternal age (16.66%), and ultrasound abnormalities (17.70%). In the postnatal group, 128 cases of KS were detected (detection rate 0.25%). Clinical presentations were primarily primary infertility/azoospermia (77.34%), and the patients were predominantly adults (84.40%). Retrospective analysis revealed that adult patients presented with specific physical signs that had been overlooked during childhood. CONCLUSION As KS lacks typical early clinical manifestations, diagnosis is often delayed until adulthood when reproductive needs arise, showing a pattern of "passive detection" and resulting in missed opportunities for optimal intervention. By conducting a comparative analysis of prenatal diagnostic data and postnatal retrospective data, a risk association model linking prenatal screening indications with childhood-specific signs was developed. This study has provided empirical evidence for establishing a multidisciplinary, full life-cycle management system of "screening ~ diagnosis ~ monitoring ~ intervention" helping to shift from "passive detection in adulthood" to "proactive management across the entire life course," and laid a foundation for improving early diagnosis rate and long-term quality of life for patients.
Humans ; Klinefelter Syndrome/genetics* ; Female ; Adult ; Pregnancy ; Retrospective Studies ; Prenatal Diagnosis/methods* ; Male ; Phenotype ; Karyotyping ; Young Adult ; Adolescent ; Middle Aged

Female ; Fertilization in Vitro ; Humans ; Klinefelter Syndrome/genetics* ; Pregnancy ; Preimplantation Diagnosis ; Sperm Injections, Intracytoplasmic

Klinefelter syndrome (KS) is characterized by small testes, gynecomastia, tall stature, and hypergonadotropic hypogonadism. This condition is associated with extra X chromosomes. It is well known that these aneuploidies predispose individuals to the development of several cancers. Moreover, there are many case reports that show KS patients to have a higher relative risk for the development of malignancy. However, incracranial germ cell tumor (ICGCT) associated with KS is very uncommon. Herein, we report delayed diagnosis of KS in a 15-year-old boy with ICGCT, embryonal carcinoma of the pineal gland, after multimodality treatment in Korea.
Adolescent ; Aneuploidy ; Carcinoma, Embryonal ; Delayed Diagnosis ; Gynecomastia ; Humans ; Hypogonadism ; Klinefelter Syndrome ; Korea ; Male ; Neoplasms, Germ Cell and Embryonal ; Pineal Gland ; Testis ; X Chromosome

Klinefelter syndrome (KS) is the set of symptoms that result from the presence of an extra X chromosome in males. Postnatal population-based KS screening will enable timely diagnosis of this common chromosomal disease, providing the opportunity for early intervention and therapy at the time point when they are most effective and may prevent later symptoms or complications. Therefore, through this study, we introduced a simple high-resolution melting (HRM) assay for KS screening and evaluated its clinical sensitivity and specificity in three medical centers using 1373 clinical blood samples. The HRM assay utilized a single primer pair to simultaneously amplify specific regions in zinc finger protein, X-linked (ZFX) and zinc finger protein, Y-linked (ZFY). In cases of KS, the ratios of ZFX/ZFY are altered compared to those in normal males. As a result, the specific melting profiles differ and can be differentiated during data analysis. This HRM assay displayed high analytical specificity over a wide range of template DNA amounts (5 ng-50 ng) and reproducibility, high resolution for detecting KS mosaicism, and high clinical sensitivity (100%) and specificity (98.1%). Moreover, the HRM assay was rapid (2 h per run), inexpensive (0.2 USD per sample), easy to perform and automatic, and compatible with both whole blood samples and dried blood spots. Therefore, this HRM assay is an ideal postnatal population-based KS screening tool that can be used for different age groups.
DNA/genetics* ; Dried Blood Spot Testing ; Humans ; Infant ; Infant, Newborn ; Karyotyping ; Klinefelter Syndrome/diagnosis* ; Kruppel-Like Transcription Factors/genetics* ; Male ; Mass Screening/methods* ; Polymerase Chain Reaction ; Reproducibility of Results ; Sensitivity and Specificity

Klinefelter's syndrome (KS) is a genetic syndrome that presents with hypogonadism and is associated with metabolic syndrome. Patients demonstrating hypogonadism show a greater prevalence of metabolic syndrome due to changes in body composition. We aimed to determine the association between KS and dyslipidemia. The KS group comprised 55 patients who visited the infertility clinic for an infertility evaluation and were confirmed as having a diagnosis of KS. The control group comprised 120 patients who visited the clinic for health screening. Patient characteristics were compared between the two groups with respect to height, weight, body mass index (BMI), testosterone, total cholesterol, high-density lipoprotein (HDL) cholesterol, low-density lipoprotein (LDL) cholesterol, and triglyceride (TG) levels. Height and weight were significantly greater in patients belonging to the KS group, but no statistically significant difference was found with respect to the BMI. Testosterone levels in patients belonging to the KS group were significantly lower compared to the control group (2.4 ± 2.6 vs. 5.2 ± 1.8 ng/mL, P < 0.001). Compared to the control group, TG levels in patients belonging to the KS group were increased (134.9 ± 127.8 vs. 187.9 ± 192.1 mg/dL, P = 0.004) and HDL cholesterol was significantly decreased (51.2 ± 22.0 vs. 44.0 ± 9.5 mg/dL, P = 0.009). LDL cholesterol and total cholesterol were not significantly different between the two groups (P = 0.076 and P = 0.256, respectively). Significant differences were noted between patients belonging to the KS group and normal control group with respect to elevated TG and decreased HDL cholesterol levels.
Body Composition ; Body Weight ; Cholesterol ; Cholesterol, HDL ; Cholesterol, LDL ; Diagnosis ; Dyslipidemias* ; Humans ; Hypogonadism* ; Infertility ; Klinefelter Syndrome* ; Lipoproteins ; Mass Screening ; Prevalence ; Testosterone ; Triglycerides

No abstract available.
Adult ; Antineoplastic Agents/therapeutic use ; *Chromosome Deletion ; *Chromosomes, Human, Pair 9 ; Cytogenetic Analysis ; DNA Mutational Analysis ; Fusion Proteins, bcr-abl/*antagonists & inhibitors/genetics/metabolism ; Gene Expression Regulation ; Humans ; Incidental Findings ; Klinefelter Syndrome/complications/diagnosis/*genetics ; Leukemia, Myelogenous, Chronic, BCR-ABL Positive/complications/diagnosis/*drug therapy/enzymology/genetics ; Male ; Molecular Targeted Therapy ; Protein Kinase Inhibitors/*therapeutic use ; Remission Induction ; Time Factors ; Treatment Outcome

OBJECTIVETo analyze clinical characteristics of a combination of dystrophinopathies and Klinefelter's syndrome (karyotype 47, XXY) in one patient.

METHODThe patient was diagnosed as Duchenne muscular dystrophy (DMD) and Klinefelter's syndrome in Beijing Children's Hospital in March, 2013. The clinical manifestations, physical examinations and laboratory test results were analyzed respectively. The clinical characteristics of four cases reported previously were analyzed as well.

RESULTThe 8.5 years old boy presented with symptoms of walking disorder and developmental delay. The patient had facial dysmorphism, waddling gait, Gower's manoeuvre and enlarged calves.Serum creatine kinase level was 21 040 U/L, and he had mild intellectual impairment. Deletions of exons 49-54 of the dystrophin gene were found.Gene dosage analysis revealed a heterozygous deletion in his mother. Five cases have been reported till now, their age ranged from 3.5 to 18 years; 3 of them were DMD, while the other 2 cases were Becker muscular dystrophy (BMD). One of them, detected in pedigree study, whose weakness was minimal in contrast to the proband. The others came to the hospital because of walking disorder or developmental delay. All the patients had enlarged calves, some of them also had Gower's manoeuvre and waddling gait. The patients' height was between 3 rd and 50 th percentile, while 2 of them had facial dysmorphism.Some degree of mental impairment is usual. Their serum creatine kinase were 2 469-24 750 U/L.One of them was detected in pedigree study. Three of them were diagnosed by muscle biopsy, while in the other one mutation analysis was used.

CONCLUSIONThe combination of dystrophinopathies and Klinefelter's syndrome is quite rare, and has clinical features of these two diseases. Mutation analysis (or muscle biopsy) and karyotype analysis can finally diagnose the syndrome.

Child ; Creatine Kinase ; blood ; DNA Mutational Analysis ; Dystrophin ; genetics ; metabolism ; Exons ; genetics ; Gene Deletion ; Heterozygote ; Humans ; Intellectual Disability ; Klinefelter Syndrome ; complications ; diagnosis ; genetics ; Male ; Muscle Weakness ; etiology ; Muscular Dystrophy, Duchenne ; complications ; diagnosis ; genetics ; Mutation ; Pedigree

PURPOSE: Klinefelter syndrome is a chromosomal disorder present in 1 out of 400 to 1,000 male newborns in Western populations. Two-thirds of affected newborns show a karyotype of 47,XXY. Few studies have examined the incidence of Klinefelter syndrome in Korea. The aim of this study was to investigate the incidence of Klinefelter syndrome by use of prenatal screening tests. MATERIALS AND METHODS: From January 2001 to December 2010, 18,049 pregnant women who had undergone a chromosomal study for fetal anomalies were included. For fetuses that were diagnosed as having Klinefelter syndrome, the patients' medical records were retrospectively reviewed. Both parents' ages, the reason for the chromosomal studies, and karyotypes were investigated. RESULTS: We found that 22 of 18,049 (0.12%) fetuses were diagnosed with Klinefelter syndrome. The incidence of this disorder in male fetuses was 22 of 9,387 (0.23%). Also, 19 of the newborns (86.4%) showed a karyotype of 47,XXY; the other newborns showed karyotypes of 48,XXY,+21; 48,XXY,+12[12]/46,XY[54]; and 47,XXY[6]/45,X[1]/46,XY[95]. The mean age of the mothers was 36.1 years, and 2 women had a past history of a Down syndrome pregnancy. Nine mothers had a normal spontaneous delivery, 9 mothers underwent artificial abortion, and 2 fetuses were spontaneously aborted. CONCLUSIONS: The incidence of Klinefelter syndrome as reported in this study is higher than in previous studies. Further studies with a broader population should be considered to confirm these results.
Chromosome Disorders ; Down Syndrome ; Female ; Fetus ; Humans ; Incidence ; Infant, Newborn ; Infertility, Male ; Karyotype ; Klinefelter Syndrome ; Korea ; Male ; Medical Records ; Mothers ; Pregnancy ; Pregnant Women ; Prenatal Diagnosis ; Retrospective Studies

Diabetes Mellitus, Type 1 ; diagnosis ; etiology ; Humans ; Klinefelter Syndrome ; complications ; diagnosis ; Male

Biomarkers ; blood ; Child ; Chorionic Gonadotropin ; blood ; Follicle Stimulating Hormone ; blood ; Growth Disorders ; etiology ; Humans ; Klinefelter Syndrome ; complications ; diagnosis ; genetics ; Magnetic Resonance Imaging ; Male ; Mediastinal Neoplasms ; complications ; diagnosis ; surgery ; Puberty, Precocious ; diagnosis ; etiology ; Teratoma ; complications ; diagnosis ; surgery ; Testis ; pathology