CASE PRESENTATION
A 48-year-old woman presented with a one-year history of irregular heavy
vaginal bleeding. She was hemodynamically stable at presentation and
physical examination was unremarkable. Bimanual examination revealed the
cervix to be thin and dilated to 8cm with a large mass protruding from
the external os suspicious for an aborting myoma. Initial laboratory
investigations are summarized in table 1. A total abdominal hysterectomy
(TAH) and bilateral salpingo-oophorectomy (BSO) was planned and she was
optimized with blood transfusions, IV fluids and tranexamic acid.
Her surgical course was complicated by left ureteral injury requiring
left intravesical ureteral reimplant and left ureteral stent placement
by urology. Serum osmolality increased from 287 mosm/kg on admission to
322 mosm/kg. Urine electrolytes were performed at this time which showed
urine osmolarity of 93 mOsm/kg, urine sodium of 23 mmol/L, urine
chloride 30 mmol/L, urine potassium of 9.0 mmol/L and urine creatinine
of 23.5 mg/dl. Twenty-four urinary output on post-operative Day 1 was
7.1L and 11.9L on postoperative Day 2. She was extubated on
postoperative Day 2. Renal ultrasonography (Day 4 post-operation) showed
adequate placement of the left ureteral stent with left hydronephrosis.
Given the timeline of events, it was unclear if the polyuria was
secondary to ureteral injury and post-obstructive diuresis versus
diabetes insipidus. She was treated with intravenous desmopressin with a
marked reduction in urine output to 4.2L in 24 hours and increased urine
osmolarity (315m Osm/kg). MRI brain was performed which showed absence
of the posterior pituitary bright spot consistent with posterior
pituitary dysfunction suggestive of central diabetes insipidus (DI) (See
Figure 1). Further investigation revealed normal ACTH, cortisol, TSH and
IgGÂ levels. She was encouraged to drink to meet the demand of her thirst
level and was treated with desmopressin when her urine output was more
than or equal to 300ml/hr for 3 consecutive hours and serum sodium was
more than 145 mmol/L. She was discharged on Desmopressin 0.1 mg daily.