Parathyroid disorders and calcium imbalance: Pathology review


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Parathyroid disorders and calcium imbalance: Pathology review


Adrenal gland disorders

Congenital adrenal hyperplasia

Primary adrenal insufficiency

Waterhouse-Friderichsen syndrome


Adrenal cortical carcinoma

Cushing syndrome

Conn syndrome

Thyroid gland disorders

Thyroglossal duct cyst


Graves disease

Thyroid eye disease (NORD)

Toxic multinodular goiter

Thyroid storm


Euthyroid sick syndrome

Hashimoto thyroiditis

Subacute granulomatous thyroiditis

Riedel thyroiditis

Postpartum thyroiditis

Thyroid cancer

Parathyroid gland disorders





Pancreatic disorders

Diabetes mellitus

Diabetic retinopathy

Diabetic nephropathy

Pituitary gland disorders


Pituitary adenoma






Growth hormone deficiency

Pituitary apoplexy

Sheehan syndrome


Constitutional growth delay

Diabetes insipidus

Syndrome of inappropriate antidiuretic hormone secretion (SIADH)

Gonadal dysfunction

Precocious puberty

Delayed puberty

Premature ovarian failure

Polycystic ovary syndrome

Androgen insensitivity syndrome

Kallmann syndrome

5-alpha-reductase deficiency

Polyglandular syndromes

Autoimmune polyglandular syndrome type 1 (NORD)

Endocrine tumors

Multiple endocrine neoplasia

Pancreatic neuroendocrine neoplasms

Zollinger-Ellison syndrome

Carcinoid syndrome



Opsoclonus myoclonus syndrome (NORD)

Endocrine system pathology review

Adrenal insufficiency: Pathology review

Adrenal masses: Pathology review

Hyperthyroidism: Pathology review

Hypothyroidism: Pathology review

Thyroid nodules and thyroid cancer: Pathology review

Parathyroid disorders and calcium imbalance: Pathology review

Diabetes mellitus: Pathology review

Cushing syndrome and Cushing disease: Pathology review

Pituitary tumors: Pathology review

Hypopituitarism: Pathology review

Diabetes insipidus and SIADH: Pathology review

Multiple endocrine neoplasia: Pathology review

Neuroendocrine tumors of the gastrointestinal system: Pathology review


Parathyroid disorders and calcium imbalance: Pathology review

USMLE® Step 1 questions

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USMLE® Step 1 style questions USMLE

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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? 


Content Reviewers

Yifan Xiao, MD

Robyn Hughes, MScBMC


Anca-Elena Stefan, MD

Evan Debevec-McKenney

Victoria Cumberbatch

Ursula Florjanczyk, MScBMC

On the Endocrinology ward, two individuals came in. The first person is 47 year old Melania who recently went through a surgical procedure called thyroidectomy due to thyroid cancer. Melania came in with tetany and on the clinical examination, there was a positive Chvostek’s sign. The other person is 55 year old Emma, who came in with constipation, muscle weakness and bone pain. She has a history of kidney stones, specifically calcium stones and she also said that she’s been feeling down lately. Calcium, phosphate and PTH levels were taken in both individuals. Melania had low levels of calcium, high levels of phosphate and low levels of PTH, whereas Emma had high levels of calcium, low levels of phosphate and high levels of PTH.

Both individuals seem to have a problem in their parathyroids. First, a bit of physiology. The 4 parathyroid glands are on the posterior of the thyroid gland, and their main job is to keep blood calcium levels stable. Changes in the body’s levels of extracellular calcium and phosphate levels are detected by surface receptors in the parathyroid’s chief cells. Both decreased calcium levels and increased phosphate levels can signal the chief cells to release more parathyroid hormone or PTH. PTH affects many organs. In the bones it binds to osteoblasts, the bone building cells, and causes them to release RANK ligands, or RANK-L, and monocyte colony-stimulating factor, or M-CSF. These will cause osteoclast precursors to mature into osteoclasts that break down bones and release calcium and phosphate into the blood. PTH also gets the kidneys to reabsorb more calcium and excrete more phosphate. It also activates calcitriol, also known as 1,25-dihydroxycholecalciferol, or active vitamin D. Active vitamin D then goes on to cause the gastrointestinal tract to increase calcium absorption. Altogether, these effects help to increase extracellular levels of calcium with they’re low.


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  7. "Hypoparathyroidism" New England Journal of Medicine (2008)

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