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A 74-year-old woman is brought to the emergency department because of generalized muscle aching, weakness and pain in the left hand. The symptoms started gradually a few months ago and have been progressing over time. Past medical history is notable for uncontrolled hypertension, type 2 diabetes mellitus and end-stage renal disease. Her medications include amlodipine, hydralazine and insulin glargine. Her last recorded glomerular filtration rate is 20 mL/min, and she has been receiving dialysis three times per week for the past 2 years. A radiograph of the patient’s hands is shown below:

 Routine blood work is performed. Which of the following sets of findings will most likely be seen in this patient? 

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Abdominal pain

hyperparathyroidism p. 344

Acute pancreatitis p. 406

hyperparathyroidism p. 344

Alkaline phosphatase (ALP) p. 399, 473

hyperparathyroidism and p. 344

cAMP (cyclic adenosine monophosphate)

hyperparathyroidism p. 344


hyperparathyroidism p. 344

Hypercalcemia p. 615

hyperparathyroidism p. 344


hyperparathyroidism p. 344

Hyperparathyroidism p. 344

associations p. 729

calcium pyrophosphate deposition disease p. 477

cinacalcet for p. 363

lab findings p. 722

lab values in p. 472

osteoporosis p. 472

renal osteodystrophy and p. 628

Hyperphosphatemia p. 615

hyperparathyroidism (secondary) p. 344

Hypocalcemia p. 337, 615

hyperparathyroidism p. 344

Hypophosphatemia p. 615

hyperparathyroidism p. 344

Kidney stones p. 626

hyperparathyroidism p. 344

Pancreatitis p. 406

hyperparathyroidism as cause p. 344

Parathyroid adenomas

hyperparathyroidism caused by p. 344

Parathyroid hormone (PTH) p. 336

in hyperparathyroidism p. 344

Polyuria p. 624

hyperparathyroidism p. 344

Tertiary hyperparathyroidism p. 344

Vitamin D deficiency p. 350

hyperparathyroidism p. 474


With hyperparathyroidism, “hyper” refers to over, and “parathyroid” refers to the parathyroid glands, so hyperparathyroidism refers to a condition where there is an overproduction of parathyroid hormone.

Parathyroid hormone comes from the parathyroid glands which are buried within the thyroid gland, and their main job is to keep blood calcium levels stable.

Now, the majority of the extracellular calcium, the calcium in the blood and interstitium, is split almost equally between two groups - calcium that is diffusible and calcium that is not diffusible.

Diffusible calcium is small enough to diffuse across cell membranes and is separated into two subcategories.

The first is free-ionized calcium, which is involved in all sorts of cellular processes like neuronal action potentials, contraction of skeletal, smooth, and cardiac muscle, hormone secretion, and blood coagulation, all of which are tightly regulated by enzymes and hormones.

The second category is complexed calcium, which is where the positively charged calcium is ionically linked to tiny negatively charged molecules like oxalate, which is a small anion that are normally found in our blood in small amounts.

The complexed calcium forms a molecule that’s electrically neutral but unlike free-ionized calcium it’s not useful for cellular processes.

Both of these are called diffusible because they’re small enough to diffuse across cell membranes.

Finally there’s the non-diffusible calcium which is bound to negatively charged proteins like albumin.

The resulting protein-calcium complex is too large and charged to cross membranes, leaving this calcium also uninvolved in cellular processes.

Changes in the body’s levels of extracellular calcium are detected by a surface receptor in parathyroid cells that’s called the calcium-sensing receptor.

These changes affect the amount of parathyroid hormone that’s released by the parathyroid gland.


Hyperparathyroidism is a condition in which the parathyroid glands produce too much parathyroid hormone (PTH), which regulates calcium levels in the blood. Hyperparathyroidism can be primary, secondary, or even tertiary.

Primary hyperparathyroidism usually results from PTH secretion by a parathyroid adenoma. It is characterized by excess PTH that leads to high blood calcium levels (hypercalcemia), bone mass loss, kidney stones, and other health problems, such as psychiatric issues.

Secondary hyperparathyroidism develops when there are conditions like chronic kidney disease, which can lead to low calcium, high phosphate, and low vitamin D levels. It is mainly characterized by osteodystrophy, in which there is bone weakening associated with bone pain and deformation.

Finally, there is tertiary hyperparathyroidism, which occurs because of chronic secondary hyperparathyroidism from kidney disease. This leads to hypercalcemia and phosphate imbalances.


  1. "Robbins Basic Pathology" Elsevier (2017)
  2. "Harrison's Principles of Internal Medicine, Twentieth Edition (Vol.1 & Vol.2)" McGraw-Hill Education / Medical (2018)
  3. "Pathophysiology of Disease: An Introduction to Clinical Medicine 8E" McGraw-Hill Education / Medical (2018)
  4. "CURRENT Medical Diagnosis and Treatment 2020" McGraw-Hill Education / Medical (2019)
  5. "Harrison's Endocrinology, 4E" McGraw-Hill Education / Medical (2016)
  6. "Vitamin D Deficiency and Secondary Hyperparathyroidism in the Elderly: Consequences for Bone Loss and Fractures and Therapeutic Implications" Endocrine Reviews (2001)
  7. "Calcimimetics for secondary hyperparathyroidism in chronic kidney disease patients" Cochrane Database of Systematic Reviews (2014)

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