Isolated adrenocorticotropic hormone deficiency due to probable lymphocytic hypophysitis in a woman
A 22-year-old unmarried female presented with a 4-year history of general fatigue, weight loss and hypotension. She was born of non-consanguineous parents after a normal full term vaginal delivery. She reported no family or personal history of autoimmune diseases. She had no history of trauma and she did not have a history of receiving glucocorticoids.\nThere were no abnormal findings on clinical examination, she was normally pigmented, blood pressure was 95/60 mmHg with no postural fall, and she had normal body hair. Her height was 170 cm and her weight was 53 kg. Thyroid palpation was normal. She had normal pubertal development. Her menarche started at the age of 12 years and she had regular periods. She had no galactorrhea. She had no headaches, visual disturbances, polyuria, or polydipsia.\nBlood examinations showed natremia of 138 mEq/L, kaliemia of 4.1 mmol/L, calcemiaof 2.38 mmol/L, plasma glucose of 4.3 mmol/L and normal blood cell count.\nClinical findings led us to consider the possibility of adrenocortical insufficiency, and the patient underwent detailed endocrine investigations, the results of which are shown in .\nCortisol deficiency was shown clearly by both insulin-induced hypoglycemia and depot Synacthen test [intravenous injection (IV), 1μg]. Secondary hypoadrenalism was confirmed by the finding of low basal ACTH level (13.8 pg/mL, reference range: 10.3-48.3), at which the plasma cortisol was 34 ng/mL. Prolactin level was elevated at 39 ng/mL (Normal range: 5-29 ng/mL in females). She had normal growth hormone levels concomitant to hypoglycemia. In contrast, basal concentrations of follicle-stimulating hormone (FSH), luteinizing hormone (LH), estradiol, thyroid stimulating hormone (TSH), and free thyroxine (FT4) were normal. These results excluded panhypopituitarism and led us to diagnose the patient with IAD. Magnetic resonance imaging (MRI) of the hypothalamus and pituitary showed a normal-sized pituitary (pituitary height 6 mm), with no mass lesion. Thepituitary stalk has a normal thickness of 2 mm and was not deviated. Thehyperintense signal of the posterior pituitary was in the normal location.\nThe diagnosis of IAD probably secondary to LYH was made. Investigation for autoimmune diseases, including assessment of anti-thyroid peroxidase antibody (anti-TPO), anti-thyroglobulin antibody (anti-TG), anti-ovarian antibodies, anti-adrenal antibodies, anti-glutamic acid decarboxylase (anti-GAD) antibodies, and antinuclear antibodies (ANA) was negative.\nA daily dose of hydrocortisone (25 mg) was administered. After 8 months of follow-up, the patient was well-controlled, and she experienced no signs or symptoms of endocrine dysfunction.