see: [Rosen hypercalcaemia in cancer](x-devonthink-item://29E6D39F-BB62-4B17-8D78-48F9C53E1D2A?page=5&start=1036&length=13&search=HYPERCALCEMIA) > [!key points] > mnemonic:: bones, stones, abdominal groans, psychiatric overtones > - **severe** and needs tx/admission if **Ca > 3.5 mmol/L** > - if Ca <3, usually managed as outpatient > - most severe cases are caused by malignancy or hyperparathyroidism > - *rehydration* with NaCl, followed by *loop diuretic* and *bisphosphonates* is mainstay of initial treatment # symptoms - weakness - confusion - rapid increase can cause coma with levels of 3.25 mmol/L; slower increase can be only mildly symptomatic even if levels >3.75 mmol/L - dehydration/thirst - lethargy - bone pain - neuromuscular - muscle weakness - confusion - comma - behavioural disturbance - gastrointestinal - nausea, vomiting, constipation - colicky abdo pain - **pancreatitis** - duodenal ulceration - Cardiovascular - shortened QT interval - prolonged PR and QRS - rarely bradycardia, heart block, ventricular arrhythmias - hyperkalemia - polyuria - renal calculi # Causes - **malignancy** 50% - often abrupt and severe - mild [[Blood gas#Metabolic alkalosis]] usually present - usually due to *paraneoplastic syndrome*, although bony mets (breast cancer and myseloma) can cause hyper Ca - breast carcinoma - lung carcinoma especially SCC - myeloma - lymphocytic leukoemias - lymphomas - ovarian carcinoma - PTH level low - **hyperparathyroidism** 25% - parathyroid adenoma - PTH elevated 1.5 - 2 x normal - generally ↑ Ca, ↓ PO4, elevated ALP, elevated Cl- - **management:** usually conservative if Ca <3 mmol/L. surgery if > 3mmol/L. *cinacalcet* in borderline cases or where surg contraindicated 30-120mg/day. nausea only common adverse effect. - [[rhabdomyolysis]] -- usually a/w AKI - sarcoidosis - rare and mild in other granulomatous diseases - [[Tuberculosis]] - berylliosis - coccidiodomycosis - histoplasmosis - leprosy - inflammatory bowel disease - foreing body granuloma - Vitamin D intoxication -- ingestion or lymphoma (tumour secrets vitamin D) - tx 90 mg pamidronate infusion over 4H if severe - Vitamin A toxicity - milk alkali syndrome ([example](x-devonthink-item://645DC5F2-F669-4F46-AF3E-9E5F4A066001?page=72)) - caused by the excessive intake of calcium and absorbable alkali - **thiazinde diuretics** - usually after many years of therapy - rarely > 2.75mmol/L - [[​Lithium Toxicity|lithium]] - [[thyrotoxicosis]] -- usually mild hyper Ca - [[Adrenal insufficiency]] - phaemochromocytoma - Pancreatitis (an effect, not a cause, but good to have in differential if seeing ↑ Ca and abdo pain) # investigations - PTH - CXR (evidence of sarcoid or carcinoma) - XR hands showing subperiostial erosions of phalanges # Management - ==rehydration== - *NaCl, not Hartmann's* (contains Ca) - 2-4L often required - generally reduceds Ca by 0.5 - 1 mmol/L - enhance elimination - **loop diuretics** ONLY after adequate hydration achieved - "loops loose calcium" - avoid thiazides (increase Ca) - **bisphosphonates** (eg [zoledronic acid](x-devonthink-item://4303C098-05E6-4D44-9B5E-DA3DFC1B2EF2) and Risedronate) - 15 minute intravenous infusion of 4 mg in 100 mL of isotonic saline - ​readminister if necessary - reduce dose if Cr Cl <30 - adverse effects: transient fever, myalgias, infusion site reaction - steroids in haematologic malignancies eg multiple myeloma - Calcitonin 3rd line - increases renal calcium excretion - suited for pts with poor renal function - effective in ony 10-30% of patients, decreases by only 0.25 mmol/L and short duration of effect - denosumab is a monoclonal - binds to RANK-ligand and inhibits function of osteoclasts - only use if shit kidney clearance <30mL/min - usually reserved for pts with malignancy and persistent hyper Ca in spite of bisphosphonate therapy