Testicular failure in a patient with G6PC3 deficiency

Glucose-6-phosphatase-β (G6PC3) deficiency is characterized by congenital neutropenia and variable developmental disorders, including those of the cardiovascular system and the urogenital system (e.g., cryptorchidism) and a peculiar visibility of subcutaneous veins.

A patient with clinical findings suggestive of G6PC3 deficiency was investigated. Genetic, hematopathologic, immunologic, and endocrine work-up were performed.

The reported patient had binucleotide deletion mutation in G6PC3 and displayed the full spectrum of clinical manifestations associated with G6PC3 deficiency including neutropenia. The reported patient had normal bone marrow cellularity without increased apoptosis, and his neutrophils displayed normal respiratory burst activity. Endocrine work-up revealed low testosterone levels, which did not respond to human chorionic gonadotropin stimulation, extremely elevated luteinizing hormone (LH) and follicle-stimulating hormone (FSH) levels, and undetectable anti-Müllerian hormone, all of which are suggestive of testicular failure or anorchia.

Our report extends the knowledge about this syndrome and suggests a role for G6PC3 in testicular differentiation and formation. Urogenital dysmorphism could indeed be unrelated to G6PC3 and secondary to consanguinity. However, given the similar description of urogenital anomalies in previous reports of this syndrome, the dysmorphism in our patient is likely related.