Supplementary Material for: Ovotesticular Disorder of Sex Development with 46,XX/47,XXY Mosaicism: Challenges in Diagnosis, Gender Assignment, Gonadal Preservation, and Long-Term Oncologic Surveillance: A Case Report

Introduction
Ovotesticular disorder of sex development (DSD) is a rare condition, most commonly associated with a 46,XX karyotype. Mosaic karyotypes such as 46,XX/47,XXY are extremely uncommon and pose unique diagnostic and management challenges, particularly regarding gender assignment, gonadal preservation, and long-term surveillance.
Case Presentation
We report a patient with 46,XX/47,XXY mosaicism who presented at birth with ambiguous genitalia. Imaging and histology revealed a right testis, a left ovary, and both Müllerian and Wolffian structures. Following multidisciplinary evaluation and parental counseling, the child was raised as male and underwent staged masculinizing genitoplasty, including hysterectomy, vaginectomy, and hypospadias repair. At age 11, rising estradiol levels and gynecomastia led to the discovery of hormonally active ovarian tissue within the right gonad. Gonad-sparing reoperation was performed to remove the ovarian component while preserving testicular tissue. Histology confirmed the presence of follicles and intact seminiferous tubules. Despite favorable pathology, elevated gonadotropins indicated primary gonadal failure.
Discussion
This case highlights the diagnostic complexity and long-term management challenges in ovotesticular DSD with sex chromosome mosaicism. Even after early surgical intervention, residual ovarian tissue may become hormonally active at puberty. Lifelong multidisciplinary follow-up is essential to monitor endocrine function, psychosocial development, and oncologic risk in such patients.
Conclusion
Ovotesticular DSD with 46,XX/47,XXY mosaicism requires individualized, long-term care. This case underscores the importance of vigilant surveillance beyond early childhood, as hormonally active gonadal tissue may emerge later in development. Timely re-evaluation and organ-preserving interventions can support both endocrine stability and psychosocial well-being.

引言
卵睾型性发育异常（Ovotesticular disorder of sex development, DSD）是一种罕见病症，最常与46,XX核型相关。诸如46,XX/47,XXY的嵌合核型极为罕见，会带来独特的诊断与治疗挑战，尤其在性别指派、性腺保留与长期监测方面。

病例报告
我们报告1例46,XX/47,XXY嵌合型患者，该患儿出生时即出现外生殖器两性畸形。影像学与组织病理学检查显示，其右侧存在睾丸，左侧存在卵巢，同时兼具苗勒管与沃尔夫管结构。经多学科评估与家长咨询后，该患儿以男性身份抚养，并接受了分期男性化生殖器成形术，包括子宫切除术、阴道切除术与尿道下裂修复术。患儿11岁时，雌二醇水平升高与男性乳房发育症提示右侧性腺内存在具有激素活性的卵巢组织。遂行性腺保留性再次手术，切除卵巢组织并保留睾丸组织。组织病理学检查证实存在卵泡与完整的生精小管。尽管病理结果良好，但促性腺激素水平升高提示原发性性腺功能衰竭。

讨论
本病例凸显了伴性染色体嵌合的卵睾型性发育异常的诊断复杂性与长期管理挑战。即便在早期手术干预后，残留的卵巢组织仍可能在青春期出现激素活性。此类患者需终身接受多学科随访，以监测内分泌功能、社会心理发育与肿瘤风险。

结论
伴46,XX/47,XXY嵌合型的卵睾型性发育异常需要个体化的长期照护。本病例强调了在幼儿期后开展严密监测的重要性，因为具有激素活性的性腺组织可能在发育后期出现。及时的再次评估与器官保留手术可同时维持内分泌稳定与社会心理福祉。