Hypercalcaemia Flashcards
When can a result of hypercalcaemia be trusted to be a true pathological finding?
When the specimen was tkaen without a venous cuff, and the result has been corrected for albumin concentration
What is considered to be severe hypercalcaemia?
Calcium >3.5mmol/L
How is severe hypercalcaemia managed?
- Saline infusion and furosemide, to maintain fluid balance and prevent fluid overload
- Correct hypokalaemia and hypomagnesaemia
- If calcium remains high, pamidronate disodium over 2-3 days
What are the main differential diagnoses for hypercalcaemia?
- Thiazide diuretics
- Bone metastases
- Thyrotoxicosis
- Primary or tertiary hyperparathyroidism
- Myeloma
- Sarcoidosis
- Vitamin D excess
- Ectopic parathyroid hormone
What suggests that thiazide diuretics are the cause of hypercalcaemia?
- Mild hypercalcaemia
- Drug history
- Normal phosphate and alkaline phosphatase
What confirms that thiazide diuretics are the cause of hypercalcaemia?
Normal calcium when drug stopped
Where are the common sources of bone metastases?
- Breast
- Bronchus
- Kidney
- Thyroid
- Ovary
- Colon
What suggests that bone metastases are the cause of hypercalcaemia?
- Normal phosphate
- Increased alkaline phosphatase
What confirms that bone metastases are the cause of hypercalcaemia?
Secondaries on bone scan
How is hypercalcaemia caused by bone metastases managed?
- Pamidronate over 2-3 days to lower calcium
- Approrpriate treatment of neoplastic process
What suggests that thyrotoxicosis is the cause of hypercalcaemia?
- Weight loss with good appetite
- Tremor
- Palpitations
- Agitation
- Goitre
- Mildly increased calcium
How is it confirmed that thyrotoxicosis is the cause of hypercalcaemia?
- Increased T3 or T4
- Greatly decreased TSH
- Normal phosphate and alkaline phosphatase
How is thyrotoxicosis managed?
- Propanolol o control symptoms
- Carbimazole
- Written warning about agranulocytosis
What suggests that hypercalcaemia is caused by primary or tertiary hyperparathyroidism?
- Fatigue
- Constipation
- Depression
- Impaired memory
- Renal colic and kidney stones
- Stomach ulcer
- Increased BP
- Pancreatitis
- Low phosphate and increased alkaline phosphatase
What confirms that hypercalcaemia is caused by hyperparathyroidism?
Increased plasma parathyroid levels
What suggests that hypercalcaemia is caused by myeloma?
- Low back pain
- Polyuria and polydipsia
- Spinal fracture
- Normal serum phosphate and alkaline phosphatase
What confirms that myeloma is the cause of hypercalcaemia?
- Paraprotein with immunoparesis on electrophoresis
- Hypercalcaemia
- Decreased Hb
- Bence-Jones protein in urine
- Spinal x-ray showing fracture with osteolytic lesion
How is myeloma treated?
- Correct very high calcium, and oral bisphosphonate to keep calcium down
- Analgesics for bone pain
- Local radiotherapy in progressive disease
- Prompt treatment of infections
- Transfusions for anaemia
- Chemotherapy using melphalan or cyclophosphamide in conjunction with steroids
What suggests that hypercalcaemia is caused by sarcoidosis?
- Cough
- Weight loss
- Night sweats
- Shortness of breath
- Erythema nodusum
- Increased phosphate and alkaline phosphatase
- Bilateral hilar shadows on CXR
What confirms that sarcoidosis is the cause of hypercalcaemia?
- Lung function tests
- Kveim test
- Biopsy from granuloma
- Increased vitamin D levels
- Increased ACE levels
How is hypercalcacemia in sarcoidosis managed?
- Correct very high calcium, and long-term prednisolone to control calcium
- In severe cases, methylprednisolone IV or immunosuppression
What suggests that vitamin D excess is the cause of hypercalcaemia?
- Drug history
- Increased phosphate
What confirms that vitamin D excess is the cause of hypercalcaemia?
Normal calcium when drug stopped
What is usually the cause of ectopic parathyroid hormone?
Lung cancer
What suggests that ectopic parathyroid production is the cause of hypercalcaemia?
Decreased phosphate and increased alkaline phosphatase
What confirms that ectopic parathyroid hormone production due to lung cancer is the cause of hypercalcaemia?
High plasma parathyroid with presence of neoplasm
