Endocrine Abstracts

Introduction: Primary adrenal insufficiency is a classically rare but potentially serious disease due to the risk of acute adrenal crisis. Although autoimmune origin is the first etiology in adults, genetic causes are most common in children.

Herein, we reporta case of coexisting hypogonadotropic hypogonadism and growth hormone (GH) deficiency in a patient with Addison’s disease.

Observation: A 15-year-old boy was referred to our department for short stature. He had no family history of autoimmune diseases. His past medical history included a primary adrenal insufficiency. This diagnosis was established on the basis of a very low morning cortisol level of 5 nmol/l with a very high ACTH level of 419 ng/l (nr: <48 ng/l). Thus, the patient was put on replacement therapy with hydrocortisone and fludrocortisone.

On physical examination, he had a body height of 146 cm (between –2 s.d. and –3 s.d.) and an impuberism with a Tanner classification of G1A1P1. His bone age was less than 10 years. The peak of GH under insulin induced hypoglycemia test was 1 mU/l and under glucagon test 3.6 mU/l. A complete deficit in GH has been established. The evaluation of the other pituitary axes revealed hypogonadotropichypogonadism with absence of response to the GnRH test. Thyroid function (TSH and FT4) and prolactinemia were normal. The hypothalamic-pituitary MRI revealed a partial empty sella. The patient received treatment with growth hormone (at a dose of 0.02 mg/kg/day) for 2 years. The final height was 160 cm. He was also put on androgens with a normal development of secondary sexual characteristics.

Conclusion: We report an unusual coexisting of hypogonadotropic hypogonadism, GH deficiency and Addison’s disease. The autoimmune involvement of adrenal gland and pituitary is unlikely in our patient since his thyrotropic and corticotropic axes were not affected. A genetic mutation affecting both the adrenal gland and the pituitary gland should be evoked, in particular the DAX1 mutation. This mutation results in adrenal hypoplasia and hypogonadotropichypogonadism. Its role in the development of GH deficiency is not known but it has been described in the literature in particular with a novel missense NROB1 mutation.