Hypercalcemia and Hyperparathyroidism Flashcards
Hypercalcemia:
-etiologies
-Primary Hyperparathyroidism: increase bone reabsorption (break down Ca2+ into blood)
- Malignancy: occurs with solid tumors and leukemias leading to increased calcium.
- -some tumors may secrete PTHrP
-Milk-Alkali Syndome: high intake of milk or calcium carbonate (tums)
- Medications:
- -lithium (increases PTH secretion)
- -Thiazide diuretics (lower urinary ca2+ excretion)
- -Hypervitaminosis D (too much vit D leading to increased levels of calcitriol which pumps up the absorpion of calcium in the kidneys, bone, and intestines.
Pseudohypercalcemia
- what is this?
- causes
-elevation in total Ca2+ but not ionized.
Causes:
- thyrotoxicosis
- pheochromocytoma
- adrenal insufficiency
- islet cell tumors of the pancreas
- elevated platelet count
Manifestations of Hypercalcemia
“bones, stones, abdominal pain, and psychic overtones”
- bones: c/o bone pain and muscle weakness
- Stones: nephrolithiasis
- Abd pain: constipation, nausea, anorexia
- psychic: anxiety, depression, cognitive dysfunction
Renal: polydispia and polyuria (resulting in dehydration)
CV: bradycardia, shortening of QT interval, varying arrhythmias
CNS depression
Work up of Hypercalcemia
- serum Ca2+ levels
- -may be artificially elevated if tourniquet left on too long or if dehydrated
- -may be artificially elevated by elevated albumin or decreased if albumin is decreased.
- normal: 8.2-10.2mg/dl
- Ionized calcium
- -50% of calcium in this form
- -changed by blood pH
- normal: 1.15-1.35mg/dl
-albumin level( need 2 readings to confirm elevated Ca2+)
- phosphate decreased
- ALP increased
- check PTH level and if normal check PTHrP
- check 24hr urinary calcium excretion (will be low)
Treatment of Hypercalcemia
- treat the underlying etiology
- use bisphosphonates
- Calcitonin (SQ or IM)
- dialysis in in Ca2+ free bath for pts in renal failure, 2ry HPT)
Hypercalcemic crisis tx
- saline diuresis: Ca2+ > 14mg/dl
- pt usually dehydrated
- give IV calcitonin
- give IV bisphosphonates (works on the bone, stop the breakdown of the ca2+)
Hyperparathyroidism
- major etiology of what?
- etiologies of primary hyperparathyroidism?
- etiologies of secondary hyperparthyroidism?
-etiology of hypercalcemia
Etiologies 1ry:
- parathyroid adenoma**
- hyperplasia
- parathyroid carcinoma (RARE)
- ectopic lesions
Etiologies 2ry:
- D/t Malignancy: Multiple myeloma, lung, kidney, esophagus, bladder.
- Renal Disease: hypocalcemia/hyperphosphatemia
Parathyroid Carcinoma
- causes what?
- dx criteria
- tx
-hyperparathyroidism
Dx:
- local invasion of contiguous structures
- lymph node or metastatic spread
- Tx:
- SURGERY**, if not surgically treatable manage hypercalcemia
Primary Hyperparathyroidism
- Sx
- Tx
- Complications of Surgery
Sx:
- hypercalcemia
- PTH-mediated bone resorption: decreased bone density, increased risk of vertebral fractures
- HTN, left ventricular hypertrophy
Tx:
- surgical
- Minimally invasive parathyroidectomy
- asymptomatic patients: avoid -Bisphosphonates and Calcimimetic (inhibit PTH secretion)
- dialysis last resort
- meds that make hypercalcemia worse, low Ca2+ diet, physical activity, adequate hydration, and vitamin D.
Complications:
- hypocalcemia
- vocal cord paralysis**
Secondary Hyperparathyroidism Work up
- intact PTH: normal 10-50pg/ml
- serum creatinine: assess renal function
- bone-specific alkaline phosphate: assess bone turn-over
- calcitriol : vitamin D metabolites- suppressed in hypercalcemia.
- PTHrP: increased in hypercalceimia d/t malignancy
-DEXA scan: if worred about osteoporosis
I
Hypocalcemia:
- etiology
- sx mild/severe
- work up
- tx
Etiologies-hypoparathyroidism**, hypovitaminosis D, hyperphosphatemia
Sx:
mild: circumoral parasthesias, myalgias, muscle cramps, fatigue, anxiety
severe: tetany/laryngospasm, seizures, myopathy, prolonged QT interval on EKG, papilledema, hypotension, Trousseaus sign (limp wrist)
Work-up:
- decreased serum Ca2+ (make sure you know albumin levels too!)
- increased serum phosphate
- usually high PTH levels
Tx:
-vit D supplement + Calcium (elemental)
- cann add thiazide diuretic
- calcitriol
Hyperphosphatemia -etiologies -work up -teatment -
Etiologies:
- tissue breakdown (phosphate is in the cells, sepsis, rhabdo, burns may all lead to tissue breakdown and hyperphosphatemia)
- may cause hypocalcemia
- lactic acidosis/DKA
- renal failure (biggy!!) ****
- hypoparathyroidism (these patients also have hypocalcemia)
- vit D toxicity
Work up:
- Serum phosphate
- CMP: check glucose and renal function
- ABG for pH
- Urinalysis
Tx:
Acute:
-saline infusion to increase phosphate excretion
-hemodialysis
Chronic:
- low phosphate diet
- phosphate binders
Hypophosphatemia
- etiologies
- signs and symptoms
- work up
- tx
etiologies:
- redistribution of phosphate from extracellular fluid into cells.
- decreased intestinal absorption: poor intakke w/ chronic diarreha)
- increased urinary excretion: primary and secondary hyperparathyroidism
Signs and Sx:
- CNS: paresthesias, irritability, seziures, coma
- CV: decreased contractility
- MS myopathy, dysphagia, rhabdo,
- Lung: decreased ventilation
- hypercalcemia
Work up:
- serum phosphate level
- CMP
- 24hr urine phosphate***
Treatment:
- oral phosphate if less than 2.0 and pt is asx.
- IV replacement if phosphate is less than 1.0 and symptomatic
Vitamin D toxicity
- sx
- work up
- tx
Sx:
- hypercalcemia
- hypophosphatemia
- confusion, anorexia, vomiting
- extreme muscel weakness and bone demineralization
Work up:
- Vit D level
- hypercalcemia work up
Tx:
- IV saline
- if more severe: glucocorticoids, IV bisphophonateswi
Vitamin D Deficiency
- etiologies
- signs and symptoms
- presentation
- work up
- tx
Etiologies:
- elderly
- northern climate
- chronic renal disease
- GI disease/malabsorption
- liver failure
- drugs (phenytoin
Signs and Symptoms:
- bone pain
- muscle weakness
- fx’s
presentation:
- hypocalcemia resulting in hyperparathyroidism
Work up:
- Vit D level
- serum calcium
- phosphorus
- PTH
- alkaline phosphatase (ALP)
- electrolytes
- BUN and creatinine
Tx:
-oral replacement of Vit D or sun :):):)
