Chapter 50 - Calcifying Ossifying Disorders

Question 1

What are the 4 types of cutaneous calcification?

Answer 1

1) dystrophic, 2) metastatic, 3) iatrogenic, 4) idiopathic

Question 2

What are some examples of AI CTDs that exhibit dystrophic calcification?

Answer 2

Scleroderma (CREST syndrome), dermatomyositis

Question 3

What are some types of panniculitis that may be associated with dystrophic calcification?

Answer 3

Pancreatitis/carcinoma, SC fat necrosis of newborn, lupus profundus

Question 4

What are some genetic disorders that may be associated with dystrophic calcification?

Answer 4

Pseudoxanthoma elasticum, Ehlers Danlos syndrome, porphyria cutanea tarda, Werner syndrome, Rothmund Thompson syndrome

Question 5

What are some neoplasms that may be associated with dystrophic calcification?

Answer 5

Pilomatricoma, pilar cysts, BCC, chondroid syringomas, melanocytic nevi, AFX, pyogenic granuloma, trichoepitheliomas, SKs

Question 6

What are some causes of metastatic calcification?

Answer 6

Chronic renal failure (most common), milk-alkali syndrome, hypervitaminosis D, hyperparathyroidism, neoplasms

Question 7

What are the clinical features of calciphylaxis?

Answer 7

Violaceous reticulated patches, +/- bullae, ulcer, extremely painful, death due to gangrene and sepsis

Question 8

What are the 4 genetic d/o with ossification as a regular feature?

Answer 8

1) fibrodysplasia ossificans progressiva, 2) progressive osseous heteroplasia, 3) plate like osteoma cutis, 4) Albright hereditary osteodystrophy

Question 9

What is miliary osteoma?

Answer 9

Common foci of cutaneous ossifcation on the face, may be associated with crhonic acne vulgaris, multiple small firm papules (skin, white, blue color)

Question 10

What lab work would you consider ordering in a patient with a possible calcification/ossification disorder?

Answer 10

Serum calcium, phosphate, PTH, and vitamin D3, in addition to 24 hour urinary calcium excretion. Also, consider ordering protein C activity and function, if calciphylaxis is suspected.

Question 11

True or false: the treatment of military osteoma cutis is primarily surgical.

Answer 11

True; laser resurfacing with curettage of exposed osseous fragments has also be described, as has tretinoin gel

Question 12

Patients with progressive osseous heteroplasia, plate-like osteoma cutis, and Albright hereditary osteodystrophy all have mutations in which gene?

Answer 12

GNAS1, which encodes the alpha subunit of the stimulatory G protein which regulates adenyl cyclase activity (adenyl cyclase is believed to be a regulator of bone formation)

Question 13

What are the two main mechanisms of bone formation that can be seen in disorders of cutaneous ossification?

Answer 13

Endochondral and intramembranous

Question 14

There are four genetic disorders that feature cutaneous or subcutaneous ossification as a regular feature. What are they?

Answer 14

Fibrodysplasia ossificans progressiva, progressive osseous heteroplasia, plate-like osteoma cutis, and Albright hereditary osteodystrophy

Question 15

What is the most common cause of iatrogenic calcification?

Answer 15

Extravasation of calcium gluconate, calcium chloride, or phosphate-contaning intravenous injections