Hypercalcaemia

CLINICAL DIAGNOSTIC MANUAL

Hypercalcaemia is defined as an elevated plasma calcium concentration, typically above 10.5 mg/dL. This condition can result from various pathologies affecting calcium metabolism, including hormonal disorders, neoplasms, and metabolic dysfunctions.

Hypercalcaemia can be asymptomatic in mild cases, but severe cases may lead to significant complications affecting multiple organ systems. Managing hypercalcaemia requires careful evaluation of the underlying cause to provide appropriate treatment and prevent serious complications.

Pathology	Clinical Symptoms and Signs	Suspected Diagnosis	Confirmatory Diagnosis
Severe hypercalcaemia	Muscle weakness, fatigue, polyuria, polydipsia, nausea, vomiting, abdominal pain, constipation, confusion, arrhythmias	Very high serum calcium levels	Serum calcium measurement, ECG, clinical evaluation
Thiazide diuretics	Muscle weakness, fatigue, polyuria, polydipsia, nausea, vomiting	History of thiazide diuretic use	Serum calcium measurement, medication review
Bone metastases	Bone pain, pathological fractures, muscle weakness, fatigue	History of known cancer, bone pain	Imaging studies (X-rays, CT, MRI), tumour markers, bone biopsy
Thyrotoxicosis	Weight loss, tremors, tachycardia, muscle weakness, fatigue	History of hyperthyroidism, thyroid symptoms	TSH, T3, and T4 measurement, thyroid imaging
Primary hyperparathyroidism	Muscle weakness, fatigue, polyuria, polydipsia, nausea, vomiting, abdominal pain, constipation	Symptom history, elevated serum calcium levels	PTH measurement, serum calcium, parathyroid imaging
Multiple myeloma	Bone pain, anaemia, muscle weakness, fatigue, pathological fractures	History of systemic symptoms, elevated blood and urine proteins	Serum calcium measurement, protein electrophoresis, bone marrow biopsy
Sarcoidosis	Fatigue, weakness, chest pain, cough, dyspnoea	History of respiratory and systemic symptoms	Chest X-ray, CT, biopsy of affected tissue, serum calcium levels
Vitamin D excess	Muscle weakness, fatigue, nausea, vomiting, abdominal pain, constipation	History of excessive vitamin D intake, elevated calcium levels	Serum calcium and vitamin D measurement
Parathyroid hormone-related peptide (PTHrP) excess (lung cancer)	Muscle weakness, fatigue, nausea, vomiting, abdominal pain, constipation, respiratory symptoms	History of lung cancer, elevated serum calcium	PTHrP measurement, chest imaging, tumour biopsy