MSFinals-0404

MSFinals-0404

A 70-year-old woman with metastatic carcinoma of the breast is admitted to your ward, as her family are finding it difficult to cope with her deterioration over the past two weeks. She appears drowsy and lethargic. She has known hepatic and bony secondary lesions.
Her admission blood tests are:
Investigation Result Normal value
Sodium (Na+) 137 mmol/l 135–145 mmol/l
Potassium (K+) 3.9 mmol/l 3.5–5.0 mmol/l
Urea 7.9 mmol/l 2.5–6.5 mmol/l
Creatinine 98 μmol/l 50–120 µmol/l
Calcium Ca2+ 3.13 mmol/l 2.20–2.60 mmol/l
PO43− 0.87 mmol/l 0.70–1.40 mmol/l
Magnesium (Mg2+) 0.91 mmol/l 0.75 –1.00 mmol/l
Albumin 37 g/l 35–55 g/l
Haemoglobin 103 g/l 115–155 g/l
Mean corpuscular volume (MCV) 98.3 fl 76–98 fl
White cell count (WCC) 8.1 × 109/l 4–11 × 109/l
Platelets 186 × 109/l 150–400 × 109/l
Which of the following is the most appropriate initial treatment for this lady’s hypercalcaemia?