Hypocalcaemia

Question 1

What are the causes of Hypocalcaemia?

Answer 1

Raised Phosphate – Hypoparathyroidism, Secondary Hyperparathyroidism (E.g. In CKD), Rhabdomyolysis (Release of intracellular Phosphate precipitates the calcium), Hypomagnesemia
Normal/Low phosphate – Malabsorption, Alkalaemia (Ionised (active) calcium, is reduced in alkalosis), Pancreatitis, Fluid Overload, Vitamin D deficiency, Osteomalacia/Bisphosphonates

Question 2

What will you find on a history of Hypocalcaemia?

Answer 2

Symptoms: - SPASMODIC
Spasm painful spasm of the hands and feet – Trousseaus sign
Perioral Paraesthesia
Anxious/Irritable
Seizures
Muscle tone increased – Colic, Wheeze, Dysphagia
Orientation impaired/confusion
Dermatitis
Impetigo Herpetiform
Chvostek’s sign/Cataracts/Cardiomyopathy (Long QT syndrome)

Risk Factors:
Neck Surgery - Removal of parathyroid
Immobile - E.g. Nursing home could indicate vitamin D deficiency
Underlying malabsorption e.g. Crohns/Coeliac - malabsorption of calcium/albumin (that carries the calcium)

Specific Questions to ask:
Fatigue, muscle weakness, cramps, and pain may suggest vitamin D deficiency
Abdominal pain suggests the possibility of acute pancreatitis

Question 3

What will you find on examination of Hypocalcaemia?

Answer 3

End of the bed:
Deformity e.g. Kyphoscoliosis - Could indicate Vitamin D deficiency
Hands:
Trousseau’s sign – Inflating Blood Pressure cuff around arm for 3 mins will cause contraction/spams of hand muscles
Arrhythmia
Neck:
Look for surgical scars
Face:
Chvostek’s Sign - Tapping on parotid (facial nerve) causes facial muscle spasm

Question 4

What investigations will you order in Hypocalcaemia?

Answer 4

Bedside:
ECG -Looking for long QT interval and arrhythmias
Full set of observations

Bloods:
U&E - Looking for any impaired Renal Function
Parathyroid Function Tests – Hypoparathyrosism or Secondary Hyperparathyroidism
Vitamin D levels - Rule out Vitamin D deficiency
Phosphate levels – To rule outRaised in hypoparathyroidism, CKD, Hypomagnesia or rhabdomyolysis
Magnesium Levels - Can cause hyperparathyroidism
LFT’s - Looking for a raised ALP that could indicate Osteomalacia
Creatinine Kinase in suspected rhabdomyolysis
Amylase if pancreatitis suspected

Question 5

What is the treatment of Hypocalcaemia?

Answer 5

Medical:
Mild (Ca>1.9) – Oral Calcium and Vitamin D supplements, daily calcium levels
Severe (Ca <1.9) - Calcium Gluconate 10% 10ml IV in 40ml saline over 30 mins
Treat underlying cause

Question 6

What is hypocalcaemia?

Answer 6

Normal Calcium levels are between 8.5 and 10.2. Any value below 8.5 is hypercalcaemic
Symptoms can be vague – In general: Calcium Abnormalities  Muscles
Investigate logically – In general: Calcium  Look at Phosphate level? i.e. PTH