Mrs AG
Presenting complaint
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Mrs AG
75 years old
Admitted 19/9/07
5 day history
Uncontrolled shaking
 Nausea
 Poor appetite
 Feeling ‘lousy’
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History of presenting complaint
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Previous cancer of the breast
Had mastectomy and radiotherapy Apr 2006
 Diagnosed with bony metastatic disease Summer
2007
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History of presenting complaint
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Commenced on sodium clodronate
1.6grams/day in August 2007
Stopped after 2 days due to diarrhoea
Restarted 3rd Sept 2007 at 400mg/day
Stopped on the 14th Sept due to diarrhoea
History of presenting complaint
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Then developed
Nausea
 Poor appetite
 Uncontrollable shaking
 Paraesthesiae in hands and legs
 Muscle cramps
 Unable to mobilise
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Past medical history
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Metastatic Ca. breast
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Hypertension
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Hypercholesterolaemia
Drug history
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Allergies
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Penicillin and
Erythromycin
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Aspirin 75mg OD
Atorvastatin 10mg ON
Lisinopril 20mg OD
Allopurinol 100mg OD
Anastrazole 1mg OD
Frusemide 40mg OD
Esomeprazole 20mg OD
Social and Family History
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Lives with husband
Independent in all ADL’s normally
Non-smoker, moderate alcohol
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No family history of note
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On examination
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Tremulous
Tachycardic
BP 160/86
Afebrile
RR 20, Sats 97% on air
On examination
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Clear chest
Abdo soft and non-tender
Marked resting and action tremor
Peripheral paraesthesiae
No signs of DVT
Investigations
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ECG – Sinus tachycardia, normal QT
CXR – Some areas of shadowing right and left
lung fields ??mets
Previous CT abdo/pelvis – widespread sclerotic
bony lesions, ?lung mets
Investigations
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Bloods on admission
WCC 8.5, Hb 12.8
 Na 145, K 3.8, Urea 5.5, Creat 71
 Corr Ca 2+ 1.36, PO 4 1.60
 LFT’s normal except Alk phos 166
 TSH and haematinics normal
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Impression
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Profound hypocalcaemia secondary to
bisphosphonate therapy and frusemide
Treatment
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Commenced on Calcichew D3 Forte 2 tabs OD
Given 10mls of 10% calcium gluconate
Further 100mls of 10% calcium gluconate * 2
Magnesium 5 grams infused (Mg level 0.15 prior
to infusion)
Frusemide stopped
Further tests
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Short synacthen test – normal response
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PTH 5.5 (1.6 – 6.9)
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PTH appears low for degree of hypocalcaemia, this
may be due to hypomagnesaemia which can interfere
with physiological release of PTH in hypocalcaemia
Further tests
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Vitamin D level
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15.3
<10 – deficiency
 10-20 – may indicate deficiency
 >20 - adequate
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Patient progress
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24/9/07
Feeling much better. No longer shaking as much, no
paraesthesia, no cramps
 Mobile with zimmer frame
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Ca 2+ 2.11, Mg 0.53
25/9/07
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Mobile independently on ward – discharged home
Hypocalcaemia
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Hypocalcaemia occurs when calcium is lost from
the extra cellular fluid in greater quantities than
can be replaced by the intestine or bone.
Symptoms/signs of hypocalcaemia
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Paraesthesiae of distal extremities and circumoral area
Chvostek and Trousseau signs
Muscle cramps
Laryngospasm
Tetany
Seizures
Prolonged QT interval which can progress to VF or
heart block
Causes of hypocalcaemia
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Vitamin D deficiency
Hypomagnesaemia
Loop diuretics
Hypoparathyroidism
Pseudohypoparathyroidis
m
Chronic renal failure
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Post parathyroidectomy
Rhabdomyolysis
Malignant disease
Acute pancreatitis
Septic shock
Causes of hypocalcaemia
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Hypoparathyroidism
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Deficiency of PTH leads to increased renal calcium
excretion and decreased intestinal calcium
absorption (secondary to reduced 1,25(OH)2D3
production)
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(Note: PTH stimulates renal hydroxylation of
25(OH)D3 to 1,25(OH)2D3)
Causes of hypocalcaemia
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Pseudohypoparathyroidism
Rare hereditary disorder
 Affects target-cell response to PTH
 PTH is raised
 Patients can have shortened metacarpals and
metatarsals along with short stature.
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Causes of hypocalcaemia
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Malignancy
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Prostate and breast can cause increased osteoblastic
activity leading to increased bone formation and
hypocalcaemia.
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Rapid cell destruction secondary to chemotherapy
increases serum phosphorus. This complexes with
serum calcium leading to hypocalcaemia.
Causes of hypocalcaemia
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Rhabdomyolysis
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Release of cellular phosphorus, again binding to
serum calcium causing hypocalcaemia.
Causes of hypocalcaemia
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Renal failure
Reduced phosphorus excretion with continued
intestinal phosphorus absorption leads to
hyperphosphataemia
 This leads to decreased conversion of 25(OH)D3 to
1,25(OH)2D3
 This leads to decreased intestinal calcium
absorption.
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Causes of hypocalcaemia
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Hypocalcaemia and hypomagnesaemia often coexist
Can be due to decreased absorption or poor
dietary intake.
Hypomagnesaemia impairs PTH secretion and
can interfere with its peripheral action.
Causes of hypocalcaemia
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Pancreatitis
Release of pancreatic lipase causing degradation of
retroperitoneal omental fat
 Binding of calcium in the peritoneum resulting in
hypocalcaemia.
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Septic shock
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Unknown mechanism
Discussion
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There are a number of reports of symptomatic
hypocalcaemia following intravenous
bisphosphonate therapy. However, this is
uncommon with oral therapy.
Usually, compensatory mechanisms, i.e. increase
in PTH secretion act to correct calcium levels.
Discussion
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Newer, more potent bisphosphonates may
reduce the effects of PTH on bone resorption.
Hypomagnesaemia can impair the compensatory
increase in PTH secretion.
Patients should have calcium and vitamin D
status checked along with magnesium,
phosphate and renal function levels prior to
commencing potent bisphosphonate therapy.