Mosaic trisomy 13 and constitutional delay in puberty.

Patau syndrome is the third most frequent chromosomal trisomy, with an estimated mortality rate that is about 50 times higher than the general neonatal mortality rate. Trisomy 13 mosaicism is a subtype that may result in a milder form of the disease, potentially leading to a longer life expectancy in these patients, allowing them to reach puberty. In this report, we discuss the case of a young boy who was evaluated for delayed puberty and karyotyping revealed mosaicism for trisomy 13. A detailed history, physical examination and appropriate laboratory studies and imaging were performed that showed a picture of suggestive of hypogonadotropic hypogonadism and an abnormal male karyotype with mosaicism for trisomy 13. To date, there is no clear explanation to the association between trisomy 13 and gonadal axis, specifically with normal imaging of pituitary. We postulate that delayed puberty could be a clinical feature of mosaic trisomy 13.