Endocrine Abstracts

Introduction: The association of central diabetes insipidus (CDI) and acute myeloid leukaemia is rare. The onset of CDI is variable during the disease course and can be a presenting feature of AML

Case: : A 75 years old Caucasian male patient presented with acute right sided abdominal pain. His initial CT abdomen was normal. He had normocytic anaemia, thrombocytosis and monocytosis. A repeat CT scan 3 days later showed bilateral swollen adrenal glands and an inflammatory process affecting the retroperitoneum. Prior to this, he reported headaches for 2 months associated with symptoms of polyuria and polydipsia. Diabetes Mellitus had been excluded in primary care. Endocrine investigation showed a low morning cortisol of 59 nmol/l with ACTH of 20.1 ng/l and free T4 pmol/l of 6.6 with TSH of 1.27mU/l in keeping with mixed primary and secondary adrenal insufficiency and secondary hypothyroidism respectively. MRI pituitary showed focal thickening of the pituitary infundibulum. Subsequent water deprivation testing was equivocal but arginine vasopressin test was normal with initial Co-peptin levels of 3.8 pmol/l rising to 3.9 pmol/l after Arginine infusion. Steroid and levothyroxine replacement was commenced. Due to ongoing symptoms desmopressin was given with good response. Initial suspicion was IgG-4 disease with pituitary and retroperitoneal involvement. PET CT scan showed resolving adrenal oedema and completely resolved retroperitoneal inflammatory changes. However, there was diffuse homogeneous marrow activity and mild splenic activity. A blood film showed circulating blasts and a bone marrow biopsy confirmed AML with AML FISH panel showing monosomy 7. He was commenced on Azacitidine and Venetoclax chemotherapy with good response to treatment so far and resolution of some of the endocrinopathies.

Conclusion: The association of AML with monosomy 7 and CDI has been reported in the literature. Our patient also presented with anterior pituitary and adrenal involvement (hypophysitis and adrenalitis) which responded well to AML treatment with partial resolution of hormone deficiencies.