A recent study has cast new light on the growth patterns, gonadal function, and tumor risk in Chinese children and adolescents with 45,X/46,XY mosaicism. Published in BMC Pediatrics, the research undertaken by a multidisciplinary team at Shenzhen Children’s Hospital examined the records of 32 patients to provide a deeper understanding of the condition’s implications.
Background
Mosaicism of the 45,X/46,XY karyotype is a chromosome anomaly characterized by presence of both monosomic (45,X) and disomic (46,XY) cell lines within an individual. The study in question, which was conducted over a period extending from August 2005 to September 2018, sought to understand the associated health risks better. Through a historical look at these patients, the report offers critical insights for both medical professionals and affected families.
Findings
The research reported in the article with DOI 10.1186/s12887-019-1520-9 indicates that the age of diagnosis for the condition ranged from under a year old to over 16 years of age. Notably, a significant number of patients exhibited ambiguous genitalia, while several presented with short stature, and one showed a lack of breast development at diagnosis.
Genital appearance varies, with the study measuring the external masculinisation score (EMS) to quantify the degree of genital virilization. Those raised as males had a median EMS of 4.5, while in the group raised as females, the median score was 0. This indicates a wide-ranging spectrum of genital phenotypes in patients with 45,X/46,XY mosaicism.
Crucially, growth data indicated a normative pattern until the age of 2. However, after this age, a noticeable deceleration in growth occurred. Interestingly, the study found a higher incidence of short stature among females when compared to males (76.9% versus 50.0%).
Regarding gonadal function, the majority of patients showed either complete gonadal dysgenesis (CGD) or mixed gonadal dysgenesis (MGD), thus reflecting the diverse spectrum of gonadal development in these individuals. Tumorous gonadal developments, such as gonadoblastoma, were detected in a worrying 18.8% of gonads among children older than two years. The palpable gonads constituted half of these cases, underscoring the necessity for vigilant monitoring.
Alarmingly, all patients with detected gonadoblastoma were raised as females, suggesting that tumor risk might relate more closely to gonadal morphology than the gender of rearing. The findings of this study underscore the need for careful and ongoing assessment of individuals with 45,X/46,XY mosaicism.
Ethical Considerations
The study was conducted with the approval of the Ethics Committee of Shenzhen Children’s Hospital and without compromising patient privacy or consent, aligning with ethical academic standards.
Implications and Recommendations
The study’s outcomes highlight several critical recommendations for health management in children with 45,X/46,XY mosaicism. Firstly, regular growth monitoring is vital for early detection of deceleration trends, which appear common after the age of 2. Furthermore, due to the significant tumor risk identified, proactive and routine gonadal assessments, including ultrasound and biopsy where appropriate, are crucial.
The need for multidisciplinary collaboration in managing such patients was made evident by the range of medical specialists involved in diagnosing and treating the various aspects of 45,X/46,XY mosaicism. Endocrinologists, pediatricians, urologists, geneticists, and oncologists must all play a role in the long-term monitoring and care.
Keywords
1. 45,X/46,XY Mosaicism
2. Gonadal dysgenesis
3. Ambiguous genitalia
4. Short stature in children
5. Gonadoblastoma risk
References
1. Pan, L., Su, Z., Song, J., Xu, W., Liu, X., Zhang, L., & Li, S. (2019). Growth data and tumour risk of 32 Chinese children and adolescents with 45,X/46,XY mosaicism. BMC Pediatrics, 19, 143. https://doi.org/10.1186/s12887-019-1520-9
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