Endocrine Abstracts

History: A 52-year-old woman was referred by her GP for colonoscopy in view of 7 months” history of unexplained weight loss of nearly 2.5 stones, constipation and recently detected normocytic anaemia. Her past medical history was unremarkable except for bronchial asthma that was managed with albuterol. However, on the day of the scheduled colonoscopy, she was noted to be hypotensive (BP- 63/38 mm Hg, heart rate 93 bpm) and was hence admitted for fluid resuscitation. Following admission (day 1), she received 3 L of Hartmann”s solution intravenously for hypotension and severe dehydration. On day 2, the patient was found to be delirious and noted to have a random blood glucose of 1.6 mmol/l, which was treated with intravenous 10% dextrose. Serum electrolytes were normal (Na 135 mmol/l; K+ 4.2 mmol/l). Unfortunately, attempts to restore the BP failed despite adequate fluid resuscitation with 1 L of normal saline and 1 L of Hartmann”s solution (BP 96/40). Subsequently, on day 3, she was detected to have hyponatremia (Na 124 mmol/l) which was treated with 1 L of normal saline. However, over the next 4 days, her serum sodium level dropped further to 117 mmol/l in spite of daily fluid resuscitation with normal saline and Hartmann”s solution. Hyponatraemia-related work-up showed plasma osmolality-246 mOsm/kg, urine osmolality-341 mOsm/kg and urinary Na-45 mmol/l. She was hence referred to the endocrinologist. As her clinical profile was suggestive of hypocortisolism (hypoglycaemia, hyponatremia and hypotension), a random cortisol was carried out, which was found to be very low (26 nmol/l). Subsequently, a short Synacthen test (SST) revealed suboptimal response with baseline serum cortisol of 21 nmol/l and 88 nmol/l at 30 minutes. A diagnosis of Addison”s disease was made. CT adrenals revealed a normal study.

Treatment: She was treated with IV hydrocortisone 200 mg stat followed by 100 mg QDS, along with 100 mg of fludrocortisone daily. Saline infusions were continued. With the above treatment, hypotension and hyponatraemia resolved. At discharge, the patient was switched to oral maintenance therapy with hydrocortisone (10mg at 08:00, 10 mg at 12:00 and 5 mg at 17:00) and fludrocortisone 100 mg daily. She remains under endocrine follow up and has regained her weight.

Discussion: Atypical presentations of Addison” s disease as above mandate a high index of suspicion to ensure early diagnosis and prompt treatment.