Parathyroid disorders and calcium imbalance: Pathology review
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Parathyroid disorders and calcium imbalance: Pathology review
Endocrine system
Adrenal gland disorders
Congenital adrenal hyperplasia
Primary adrenal insufficiency
Waterhouse-Friderichsen syndrome
Hyperaldosteronism
Adrenal cortical carcinoma
Cushing syndrome
Conn syndrome
Thyroid gland disorders
Thyroglossal duct cyst
Hyperthyroidism
Graves disease
Thyroid eye disease (NORD)
Toxic multinodular goiter
Thyroid storm
Hypothyroidism
Euthyroid sick syndrome
Hashimoto thyroiditis
Subacute granulomatous thyroiditis
Riedel thyroiditis
Postpartum thyroiditis
Thyroid cancer
Parathyroid gland disorders
Hyperparathyroidism
Hypoparathyroidism
Hypercalcemia
Hypocalcemia
Pancreatic disorders
Diabetes mellitus
Diabetic retinopathy
Diabetic nephropathy
Pituitary gland disorders
Hyperpituitarism
Pituitary adenoma
Hyperprolactinemia
Prolactinoma
Gigantism
Acromegaly
Hypopituitarism
Growth hormone deficiency
Pituitary apoplexy
Sheehan syndrome
Hypoprolactinemia
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
Pheochromocytoma
Neuroblastoma
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
Assessments
Parathyroid disorders and calcium imbalance: Pathology review
USMLE® Step 1 questions
0 / 6 complete
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USMLE® Step 1 style questions USMLE
of complete
Routine blood work is performed. Which of the following sets of findings will most likely be seen in this patient?
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Transcript
Contributors
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.
Sources
- "Robbins Basic Pathology" Elsevier (2017)
- "Harrison's Principles of Internal Medicine, Twentieth Edition (Vol.1 & Vol.2)" McGraw-Hill Education / Medical (2018)
- "Textbook of Medical Physiology" Elsevier España (2006)
- "Davidson's Principles and Practice of Medicine" Churchill Livingstone (2010)
- "Primary, Secondary and Tertiary Hyperparathyroidism" Springer (2015)
- "Primary hyperparathyroidism: review and recommendations on evaluation, diagnosis, and management. A Canadian and international consensus" Osteoporosis International (2016)
- "Hypoparathyroidism" New England Journal of Medicine (2008)
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