Ch. 9 Fatigue, Constipation, and Depressed Mood Flashcards
What is the differential dx of hypercalcemia?
What is the most common cause of hypercalcemia in hospitalized patients?
What is the most common cause of hypercalcemia in the outpatient setting?
Hospitalized: malignancy
Outpatient: primary hyperparathyroidism
Hypercalcemia presentation
- Stones: Kidney stones
- Bones: Bone pain, pathologic fractures
- Groans: Muscle pain and weakness, pancreatitis, gout, constipation
- Psychiatric overtones: Depression, anorexia, anxiety
What are the renal manifestations of hypercalcemia?
What are the gastrointestinal manifestations of hypercalcemia?
What are the neurological manifestations of hypercalcemia?
Renal:
- Nephrolithiasis (8%)
- Nephrocalcinosis (<5%)
- Polyuria
- Polydipsia
- HTN
GI:
- Constipation
- N/V
- Heartburn
- Abdominal pain
Neurologic:
- Fatigue
- Depressed mood
- Difficulty concentrating
- Impaired memory
- Anxiety
- Sleep disturbance
- Proximal muscle weakness
- Psychomotor symptoms
- **Stupor/coma in extreme hypercalcemia (>14 mg/dL) more common in elderly
What patient demographic most commonly presents with hyperparathyroidism?
Postmenopausal women
Risk factors for primary hyperparathyroidism
- Exposure to low-dose therapeutic ionizing radiation
- Family hx of hyperparathyroidism
- Lithium therapy for bipolar disorder
MEN-1
MEN-2A
MEN-2B
MEN-1:
- Hyperparathyroidism
- Pituitary adenomas
- Pancreatic neuroendocrine tumors (ZE, insulinoma)
MEN-2A:
- Hyperparathyroidism
- Medullary thyroid cancer
- Pheo
MEN-2B:
- Hyperparathyroidism
- Medullary thyroid cancer
- Marfanoid habitus
- Oral neuromas
What is a hypercalcemic crisis?
Pts with severe hypercalcemia may present with:
Nausea, vomiting, confusion, mental status changes
MEDICAL EMERGENCY –> severe hypercalcemia –> cardiac arrhythmias + coma
Chvostek’s Sign?
Trousseau’s Sign?
Chvostek: facial twitch in response to tapping on facial nerve, anterior to external auditory canal –> reflects early tetany / sign of hypocalcemia that may arise after parathyroidectomy
Trousseau: Combination of flexion of wrist and MCP joints and extension of digits following inflation of BP cuff around arm to greater than systolic BP –> reflects early tetany
What is T-score?
Test of bone density
T-score refers to number of standard deviations below the average for a young adult at peak bone density
Normal bone has T-score better than -1
Pts with osteopenia have scores between -1 and -2.5, whereas those with osteoporosis have a score less than -2.5
What is the embryologic development of the parathyroid glands?
Superior parathyroids develop from 4th pharyngeal pouch and migrate in conjunction with the thyroid
Inferior parathyroid glands develop from 3rd pharyngeal pouch and migrate inferiorly in conjunction with the thymus
What is the typical pathology in primary hyperparathyroidism associated with the MEN disorders?
Unlike sporadic primary hyperparathyroidism, which is usually due to a single adenoma, with MEN disorders, the gene is expressed in all glands and is thus characterized by 4-gland hyperplasia
What are the end organs affected by hypocalciuric hypercalcemia, and what are the effects?
Does an elevated PTH level combined with an elevated serum calcium level establish the dx of primary hyperparathyroidism?
Not entirely.
Urinary calcium is needed to r/o hypocalciuric hypercalcemia (FHH). FHH = rare (1 in 78,000). A high urine calcium level with a high PTH level and high serum calcium level confirms primary hyperparathyroidism. A low urine calcium level suggests FHH.
How can the serum chloride to phosphate ratio suggest primary hyperparathyroidism?
Serum chloride to phosphate ratio > 33 = highly suggestive of hyperparathyroidism
PTH acts on kidney and increases calcium reabsorption as well as excretion of bicarbonate and phosphate
Excretion of bicarbonate results in a rise in serum chloride to balance ion charges, resulting in HYPERCHLOREMIC METABOLIC ACIDOSIS
What other tests should be ordered in a new dx of hyperparathyroidism?
DEXA –> osteopenia/-porosis
Renal U/S or abdominal plain films –> nephrolithiasis
What radiologic findings are suggestive of bony involvement in hyperparathyroidism?
Plain films of the hand –> subperiosteal cortical bone resorption, most commonly in distal phalanges (PATHOGNOMONIC FOR HPTH!)
In advanced disease, osteitis fibrosa cystica (mainfested by brown tumors… lucency left by overactive bone breakdown and subsequent fibrosis)
What tests help localize the involved gland in hyperparathyroidism?
99-m technetium sestamibi scanning and U/S
**WATCH OUT! Sestamibi is also taken up by thyroid tissue. Hence, a thyroid nodule can mimic the appearance of a parathyroid adenoma**
What are the indications for parathyroidectomy in pts with primary hyperparathyroidism?
What is the non-operative mgmt of pts with hyperparathyroidism?
Non-operative:
- Monitoring of serum calcium and serum creatinine annually
- Bone mineral density should be measured every 1-2 years
- Bisphosphonates may stabilize or improve bone mineral density
- Cinacalcet, a calcimimetic, may be used to reduce the serum calcium (though it has no benefit with regard to bone density)
What is the role of intraoperative PTH monitoring?
Because of the short half-life of PTH (about 4 min), intraoperative rapid PTH testing may aid in determining the completeness of parathyroid resection.
The most commonly used protocol involves drawing PTH levels at the time of gland excision and again 10 min post-excision. A fall of >50% in the PTH level is associated with a 98% long-term cure rate.
What are the surgical options for hyperparathyroidism?
What is the post-op mgmt following parathyroidectomy?
Monitor for:
- Neck hematoma
- Voice changes (injury to recurrent laryngeal nerve)
- Perioral numbness
- Tingling in fingers (hypocalcemia)
Routine post-op oral calcium supplementation may alleviate minor symptoms of relative hypocalcemia and is used routinely by many expert centers
Areas where you can get in trouble:
Assuming normal calcium r/o hyperparathryoidism
Hypocalcemia that does not respond to calcium replacement
How do you treat hypercalcemic crisis?
AGGRESSIVE INFUSION OF NORMAL SALINE = 1st line
Hypercalcemic pts are often dehydrated, since hypercalcemic state impairs kidney’s ability to concentrate urine
After pt has been rendered euvolemic, loop diuretics (FUROSEMIDE), which cause calciuresis, may be added
Bisophosphonates, can also help by binding hydroxyapatite in bone and blocking osteoclast activity
**Any drugs that worsen hypercalcemia (e.g., thiazide diuretics) or exacerbate sx of hypercalcemia (digoxin) should be immediately d/c.
Diagnostic algorithm for primary hyperparathyroidism
Mgmt algorithm for primary hyperparathyroidism
What supplies blood to the parathyroid glands?
Inferior thyroid artery
What is familial hypocalciuric hypercalcemia?
Familial (AD) inheritance of a condition of asymptomatic hypercalcemia and low urine calcium (w/ or w/o elevated PTH);
In contrast, hypercalcemia from HPTH results in high levels of urine calcium
NOTE: SURGERY TO REMOVE PARATHYROID GLANDS IS NOT INDICATED FOR THIS DX
How many glands are USUALLY affected by the following conditions:
Hyperplasia?
Adenoma?
Carcinoma?
How many glands are USUALLY affected by the following conditions:
Hyperplasia? 4
Adenoma? 1
Carcinoma? 1
Parathyroid Carcinoma
- What are the signs/symptoms?
- What is the most common tumor marker?
- Tx?
- Postop complications post parathyroidectomy?
Parathyroid Carcinoma
- What are the signs/symptoms?
- Hypercalcemia
- Elevated PTH
- PALPABLE parathyroid gland (50%)
- Recurrent larygneal nerve paralysis (change in voice)
- Hypercalcemic crisis (usually associated with calcium levels >14)
- HCG
- Tx? Surgical resection of parathyroid mass w/ ipsilateral thyroid lobectomy, ipsilateral lymph node resection
- Postop complications post parathyroidectomy?
- Recurrent nerve injury (unilateral)
- Neck hematoma (open at bedside if breathing is compromised)
- Hypocalcemia
- Superior laryngeal nerve injury
