1. Virtual Rounds Presentation A Case of Hypercalcemia
Heather Taylor
November 9, 2010

2. 57 year old Caucasian female Generally healthy
Hypercalcemia
57 year old Caucasian female Generally healthy

3. Hypercalcemia
Chief Complaint: review lab results (June 30) History of Illness: seen by GP in April c/o bilateral shoulder pain. Recently started exercise program O/E full ROM but weakness rotator cuff muscles & tender supraspinatus. Xrays -> bilateral calcification in rotator cuff Ca May 5th PTH normal. Repeat calcium normal. Dx rotator cuff tendonitis. Plan: repeat calcium. Exercise. NSAIDS. May 20th calcium 3.01 PTH normal

4. Hypercalcemia
June 30th Presented at clinic for lab results. c/o “normal aches and pains”, itchy eyes, drippy nose Sent for TSH, PTHrp, ionized calcium, Vit D 1,25 & Vit D 25 July 8th : c/o hx crampy abdominal pain, constipation, nausea, fatigue, skin “feels dry”, headache, irritability, leg weakness & trouble concentrating; sx for 2-3 weeks, thought was dehydrated so took Pedialyte...sx improved. similar episode 4 months ago, lasted only 2 days.

5. Hypercalcemia
Past Medical History: lichen sclerosis. Mild depression Allergies: palm oil -> wheezing Meds: Trazadone 50 mg po HS. No antacids. Calcium 1 gm/day. Vit D 800 IU/day Family History: older sister with lupus. Younger sister with arthritis. 4 sisters & niece with thyroid problems. Father, 2 sisters, daughter with depression. Mother deceased breast cancer age 62. younger sister with early CRC Social History: quit smoking 25 yrs ago. Drinks 1-5 beer &/or wine a day; can take it or leave it. CAGE neg

6. Hypercalcemia
Physical Exam General Appearance: alert, slim 57 yr old female; appears her stated age. No acute distress. BP 112/65 HR 68, regular RR 16 EENT: normal. No enlarged nodes. Thyroid not enlarged. Chest clear CVS: S1S2 normal. No murmurs Abd: soft, nontender. No masses. Neuro: CN II-XII normal. 5+ strength bilateral UE, LE. DTR 2+ Labs: Calcium 3.25 ionized calcium 1.89 TSH, CBC, PTH, CK, lytes, Bun, creatinine Vit D normal

7. Hypercalcemia
Differential Dx: ? Plan: ? Refer to Internal Medicine Pt went to Prince George for 3 wks.

8. Hyperparathyroidism & malignancy make up 90% of cases
Hypercalcemia
Results when calcium entering circulation exceeds calcium excreted in urine or deposited in bone
Due to: increased bone resorption, increased GI absorption, decreased renal excretion.
Hyperparathyroidism & malignancy make up 90% of cases

9. Causes of increased bone resorption
Hypercalcemia
Causes of increased bone resorption
Primary hyperparathyroidism: (usually not > 3.25)
increased PTH -> increased bone resorption & increased serum calcium
increased calcium absorption in GI tract
2nd ary hyperparathyroidism: often assoc with CKD; low or normal calcium; can increase with prolonged disease
3. Malignancy: hypercalcemia associated with many tumors
eg. Bone mets, multiple myeloma
PTHrp assoc with nonmetastatic solid tumors
4. Thyrotoxicosis: mild hypercalcemia in 15-20% of pts

10. Causes of increased calcium absorption
Hypercalcemia
Causes of increased calcium absorption
High calcium intake alone rarely causes hypercalcemia (elevated serum calcium -> PTH )
High calcium intake plus reduced urinary excretion ->
CKD: decreased calcium excretion/elevated serum phosphate/decreased calcitriol synthesis
Milk-Alkali syndrome: excess milk or calcium carbonate -> hypercalcemia, metabolic alkalosis & renal insufficiency

11. Excessive Vit D: increases calcium absorption & bone resorption
Hypercalcemia
Excessive Vit D: increases calcium absorption & bone resorption
1,25 -> results from:
a) excess intake calcitriol
eg. tx for hypoparathyroidism, or hypocalcemia/2nd’ary hyperparathyroidism of renal failure.
Lasts 1-2 days; tx with salt & fluids, stopping calcitriol.
Increased endogenous production
eg pts with lymphoma, chronic granulomatous disorders (sarcoidosis, Wegeners)
high 25OHD from excess Vit D or calcidiol intake
lasts longer; more aggressive tx needed

12. Other less common causes of hypercalcemia
Lithium -> increased PTH secretion
Thiazide diuretics -> decreases urinary calcium excretion
Pheochromocytoma -> rare; ?due to concurrent hyperparathyroidism
Adrenal insufficiency
Rhabdomyolysis & diuretic phase of ARF
Theophylline toxicity
Familial hypocalciuric hypercalcemia
Metaphyseal chondrodysplasia: rare form of dwarfism

13. Hypercalcemia
Diagnostic Approach
Clinical & lab evaluation to distinguish between hyperparathyroidism & malignancy
PTH-mediated: 1’ary hyperparathyroidism, familial hyperparathyroid syndromes
Non PTH-mediated: malignancy, Vit D excess, granulomatous dx
1. Repeat sample to confirm hypercalcemia
2. Clinical evaluation, duration of high calcium, presence of sx, FH, & meds may give clues.
3. PTH: frankly elevated or in upper half of normal -> primary hyperparathyroidism
4. PTH < 20 pg/ml: look for other causes.
5. PTHrp & Vit D metabolites

14. Symptoms of hypercalcemia
Polyuria, altered mentation, nausea, vomitting, constipation
Life-threatening -> arrythmia, ++volume depletion due to polyuria
Chronic mild hyperparathyroidism
Usually no symptoms
Increased risk osteopenia, renal calculi, nephrocalcinosis

15. Interpretation of serum calcium
Hypercalcemia
Interpretation of serum calcium
Hypercalciumemia due to ionized (free) calcium
40-45% calcium bound to albumin
Increased protein-binding can cause elevation in serum total calcium but not ionized calcium. Occurs in pts with hyperalbuminemia due to severe dehydration & rarely MM.
Hypoalbuminemia -> normal total calcium, but elevated ionized calcium.

16. Degree of hypercalcemia useful
< 2.75 mmol/L more likely primary hyperparathyroidism
> 3.25 mmol/L more common with malignancy
10-20% of pts with 1’ary hyperparathyroidism have PTH in upper end of normal

17. Know when to check calcium Know what to look for if elevated
Hypercalcemia
Key Points
Know when to check calcium
Know what to look for if elevated
Comprehensive hx can give clues

18. Hypercalcemia
Questions? Thank you!