Endocrine Abstracts

Introduction: Sarcoidosis is a multisystem inflammatory disease. Hypothalamic-pituitary involvement in sarcoidosis is rare and poorly described. We report here a case of pituitary insufficiency during sarcoidosis disease.

Observation: Patient aged 49 years, followed for systemic sarcoidosis with cutaneous, pulmonary and ocular tropism for 7 years, admitted for exploration of a severe polyuro-polydipsic syndrome with four nocturnal awakenings, questioning revealed secondary amenorrhea for 2 years, and physical examination found signs of intra- and extra-cellular dehydration. After eliminating the obvious causes of polyuro-polydypsic syndrome, namely diabetes mellitus and hypercalcemia, the diagnosis of diabetes insipidus was made in view of a low urinary osmolarity of 122 mosmol/l and a plasma osmolarity of 289 mosmol/l. A hormonal workup showed corticotropic, thyrotropic and gonadotropic insufficiency, and a hypothalamic-pituitary MRI revealed a hypothalamic sarcoid granuloma. We put the patient on a vasopressin test, and retained the diagnosis of central diabetes insipidus in view of the improvement in the polyuro-polydipsic syndrome and the increase in urinary osmolarity to 580 mosmol/24h. Therapeutically, our patient was put on hormone replacement therapy and vasopressin spray with a good clinical and biological evolution.

Discussion and conclusion: Neurosarcoidosis affects 5-26% of sarcoidosis patients. Hypothalamohypophyseal involvement is exceptional. It accounts for 0.5% of sarcoidosis cases, MRI provides diagnostic support in cases of clinical suspicion. The most common endocrine disorders are diabetes insipidus and hyperprolactinemia, thyrotropic insufficiency and, to a lesser degree, hypogonadism, hence the need to screen for hypothalamic-pituitary involvement in the presence of systemic sarcoidosis.