ESPE Abstracts

Background: Mutations in PROP1 gene are the most common known genetic cause of multiple pituritary hormone deficiency. It is characterized by somatolactotroph, thyrotroph, gonadotroph and sometimes corticotroph deficiencies and pituitary hyper- or hypoplasia. The karyotype 47,XYY occurrs in 1 in every 1000 live male birth. Some studies report that the phenotype of XYY syndrome includes tall stature, behavioral problems and low fertility.

Objective and hypotheses: To present the first reported case of PROP1 mutation and XYY syndrome in one patient.

Method: We describe the clinical case of 7-year-old boy with short stature and hypothyroidism.

Results: The boy was born at term from unrelated healthy parents. His birth length and weight were 53 cm and 3950 g respectively. The patient complained about short stature at 2 years old (SDS=−2.75). Karyotype was performed at 5 years old, abnormal chromosome test was received (47,XYY). Very low height (SDS −5.2), overweight (SDS +1.3), dry skin and pastosity were found at physical examinations at 7 years old. Laboratory results showed low level of free T₄ (7.0 pmol/l), normal levels of TSH (1.1 mIU/l), cortisol (537 nmol/l) and prolactin (307 mIU/l), low levels of IGF1 (3 ng/ml). Brain MRI showed anterior pituitary hyperplasia. Genetic analysis revealed compound heterozygous mutations in the PROP1 gene (c.150delA and c.301_302delAG). The boy was started on growth hormone and levothyroxin therapy. No clinical signs of XYY syndrome were found.

Conclusion: The unique combination of mutation in PROP1 gene and 47,XYY karyotype was observed. Further monitoring of the patient is required in order to detect possible abnormalities.