Hypercalcemia Flashcards
Diagnostic algorithm
- Acute
a. PTH high
- >Primary hyperparathyroidism
b. PTH low
- >Consider malignancy, PTHrP, clinical evaluation - Chronic
a. PTH low
- >Granulomatous disease
- >Familial hypercalciuric hypercalcemia
- >Milk-alkali syndrome
- >Medications: lithium, thiazides
- >Immobilisation
- >Vit D or Vit D intoxication
- >Adrenal insufficiency
- >Hyperthyroidism
b. PTH high
- >Primary, secondary, tertiary
- >Consider MEN syndrome
Primary hyperPTH: mechanism, clinical presentation, diagnostic criteria, treatment
Elevated PTH= +bone turnover
Solitary adenoma or part of MEN->nephrolithiasis, vomiting, abdominal pain, polydipsia, polyuria, depression, fatigue “stones, bone, and abdominal groans and psychic moans”
+Calcium, +PTH, low phosphate
Medical therapy for symptoms
Surgery for symptoms of hypercalciuria or osteoporosis
How does lithium cause hypercalcium
Stimulates PTH production
Malignancy-related: mechanism, clinical presentation, diagnostic criteria, treatment
Local destruction of bone
Production of PTHrP
Symptoms of hypercalcemia and of particular cancer
Imaging of bones, PTHrP levels, bone marrow biopsy
Treat tumor and control cancer
Bisphosphonates
Calcitriol
Sarcoidosis: mechanism, clinical presentation, diagnostic criteria, treatment
++Vitamin D synthesised in macrophages and lymphocytes
Low PTH elevated Vitamin D
Avoid sunlight, decrease vitamin D and calcium intake
Glucocorticoids if needed
Renal insufficiency: mechanism, clinical presentation, diagnostic criteria, treatment
Secondary as a result of partial resistance to PTH effectes
Bone pain, pruritis, ectopic calcification, osteomalacia
+Renal function
Limited dietary phosphate IV calcitriol
Overview management of hypercalcemia acute
- Hydration + loop diuretics
- Bisphosphonate
- Calcitonin->while awaiting effect of bisphosphonate
- Glucocorticoids (effective in cancer-induced, calcitriol mediated)
- Avoid exacerbating medication
- Dialysis
- Treat underlying malignancy
Corrected calcium
Add 0.8 mg/dL to the serum total calcium
for every 1 g/dL of albumin level below 4 g/dL
Most common etiology (2)
- Primary hyperparathyroidism
Clinical features
GIT: abdominal pain, peptic ulcer, vomiting, constipation
Kidney: polyuria, polydipsia, stones
CNS: psychosis, fatigue, depression
Bones: bone pain
Investigations
Total serum calcium Serum ionised calcium Serum albumin CMP, UEC, glucose Resting ECG->decreased QT Serum PTH PTHrP Serum phosphorus Calcitriol 25-hydroxyvitamin D
Consider: Skeletal survey CXR Serum electrophoresis 24 hour urinary calcium excretion
How does magnesium relate to calcium
Decreased magnesium inhibits PTH->hypocalcemia
MEN 1 malignancy
Parathyroid hyperplasia/adenoma
Pancreas endocrine->gastrinoma, insulinoma etc
Pituitary prolactinoma
MEN 2 a
Thyroid->meduallry
Adrenal phaeochromocytoma
Parathyroid hyperplasia
MEN 2b
Similar to MEN 2a, + mucosal neuromas and marfinoid appearance, no +PTH
