Hypopituitarism due to mutation in the PROP1 gene in association with the 47,XYY karyotype and autosomal dominant atrioventricular septal defect: two case reports

Application of genetic analysis in clinical practice enables identifying a combination of two rare diseases in one patient. We report two cases of patients with hypopituitarism due to PROP1 gene mutations in combination with the 47,XYY karyotype (case 1) and autosomal dominant partial atrioventricular septal defect (case 2). These clinical cases clearly demonstrate that several rare diseases can be present in one patient. The morphology of the pituitary gland has specific features in patients with a PROP1 gene mutation: signal inversion on T1- and T2-weighted images, as well as changes in size of the pituitary gland over time. In case of short stature, the hormonal evidence of secondary hypopituitarism, low IGF-1 levels, and specific morphological features observed in MRI images, we recommended carrying out molecular genetic analysis of the PROP1 gene without conducting growth hormone stimulation test.