Ch 18 Pathoma - MSK Pathology

Question 1

_____ is impaired cartilage proliferation in the growth plate, due to an activating mutation in the ______. It is autosomal dominant/recessive. Most mutations are inherited/sporadic and related to increased _____.

Answer 1

Achondroplasia; fibroblast growth factor receptor 3 (FGFR3 - overexpression inhibits growth); dominant; sporadic; paternal age

Question 2

Clinical features of achondroplasia include short ____ with normal-sized ___ and ___, due to poor ____ bone formation. ____ bone formation is not affected. Mental function, life span, and fertility are/are not affected.

Answer 2

extremities; head and chest; endochondral; intramembranous; are not

Question 3

____ bone formation is characterized by formation of a cartilage matrix, which is then replaced by bone; it is the mechanism by which ____ bones grow.

Answer 3

Endochondral; long

Question 4

____ bone formation is characterized by formation of bone without a preexisting cartilage matrix; it is the mechanism by which ____ bones grow

Answer 4

Intramembranous; flat (skull and rib cage)

Question 5

_____ is a congenital defect of bone formation resulting in structurally weak bone. Most commonly due to an autosomal/x-linked, dominant/recessive defect in ____ synthesis. Name the three clinical features

Answer 5

Osteogenesis imperfecta; autosomal dominant; collagen type I; multiple fractures of bone (can mimic child abuse w/o bruising), blue sclera (thinning of scleral collagen shows choroidal veins), hearing loss (bones of middle ear fracture)

Question 6

_____ is an inherited defect of bone resorption resulting in abnormally thick, heavy bone that fractures easily. Due to poor ___ function. ____ mutation leads to loss of acidic microenvironment needed for bone resorption (removing calcium). Tx is ___.

Answer 6

Osteopetrosis; osteoclast; Carbonic anydrase II; bone marrow transplant (b/c osteoclasts are derived from monocytes)

Question 7

Name the five clinical features of osteopetrosis

Answer 7

bone fracture (b/c no proper bone remodeling due to osteoclasts dysfunction); anemia, thrombocytopenia and leukopenia with extra medullary hematopoiesis; vision/hearing impairment (impingement on CNs); hydrocephalus (narrowing of foramen magnum); renal tubular acidosis (lack of carbonic anhydrase > dec tubular reabsorption of HCO3-)

Question 8

___ and ___ cause defective mineralization of osteoid due to a ____ deficiency. Which one is seen in adults and which one in kids

Answer 8

Rickets; osteomalacia; vitamin D
(osteoid produced by osteoblasts is normally mineralized with calcium and phosphate to form bone). Rickets in kids; osteomalacia in adults

Question 9

Vitamin D is derived from skin upon exposure to ___ and from ___. Activation requires _____ by the liver, followed by ___ by the PCT cells of the kidney. Vitamin D raises serum ___ and ___ by acting on intestine, kidney, and bone (mechanism)

Answer 9

sunlight (85%), diet (15%); 25-hydroxylation; 1-alpha-hydroxylation; calcium; phosphate; intestine: inc absorption; kidney: inc reabsorption; bone: inc resorption

Question 10

Osteomalacia results in ___ bone with an increased risk of ___. Labs include low ___ and ___ and high ___ and ___.

Answer 10

weak; fractures (esp in weight bearing bones: vertebral bodies or hip); calcium, phosphate; PTH, alk phos (needed to create an alkaline environment to lay down calcium on bone)

Question 11

_____ is a reduction in trabecular bone mass, which results in ___ bone with increased risk for fracture. Risk of it is based on ____ and ___ that follows thereafter. Most common forms are __ and __

Answer 11

Osteoporosis; porous; peak bone mass; rate of bone loss; senile; postmenopausal

Question 12

Peak bone mass is achieved by ___ years of age and is based on these three things. Thereafter, slightly less than __% of bone mass is lost each year; lost more quickly with these three things.

Answer 12

30; genetics (vit D receptor variants); diet; exercise; 1; lack of weight bearing exercise (space travel); poor diet; decreased estrogen (menopause)

Question 13

Name the the clinical feature of osteoporosis. Bone density can be measured using ___. Tx includes __, __, and __ to limit bone loss, __ to induced apoptosis of osteoclasts. ___ are contraindicated, and ___ would in theory be helpful but not recommended.

Answer 13

Bone pain/fractures (in weight bearing areas like vertebrae, hip, distal radius - height loss, kyphosis); DEXA scan; exercise, vit D, calcium; bisphosphonates; glucocorticoids; estrogen replacement therapy

Question 14

How can you tell apart osteomalacia and osteoporosis?

Answer 14

In osteomalacia, you have decreased calcium and phosphate and increased PTH and alk phos; in osteoporosis labs are normal

Question 15

____ is an imbalance between osteoclast and osteoblast function usually seen in late adulthood (>60). It’s etiology is unknown though it is possibly ___. It involves one or more bone/entire skeleton. Tx includes ___ to inhibit osteoclast function and ___ to cause osteoclast apoptosis.

Answer 15

Paget disease of bone; viral; one or more; calcitonin; bisphosphonates

Question 16

Name the 3 distinct stages of Paget disease of bone. The end result is __, __ bone that ___ easily. Bx reveals a ___ pattern of lamellar bone.

Answer 16

1) osteoclastic; 2) mixed osteoblastic-osteoclastic; 3) osteoblastic; thick, sclerotic; fractures; mosaic

Question 17

Name the five clinical features of Paget disease of bone. Name the two complications.

Answer 17

1) bone pain (due to micro fractures); 2) increasing hat size; 3) hearing loss (impingement on CN); 4) lion like facies (craniofacial bones); 5) isolated elevated alkaline phosphatase; high output cardiac failure (due to AV shunts in bone); Osteosarcoma (blasts are going cray)

Question 18

____ is an infection of marrow and bone; it usually occurs in ____. Most commonly ____; arises via hematogenous spread. _____ bacteremia (children) seeds ___. _____ bacteremia (adults) seeds ___. Dx is made by ____.

Answer 18

Osteomyelitis; children; bacterial; transient; metaphysis; open wound; epiphysis; blood culture

Question 19

Causes of osteomyelitis; most common, seen in sexually active, seen in sickle cell dx, seen in diabetics/IV drug abusers; associated with cat/dog bite; involves vertebrae (Pott dx)

Answer 19

staph aureus; N gonorrhoeae; salmonella; pseudomonas; pasteurella; mycobacterium tuberculosis

Question 20

Clinical features of osteomyelitis include __ pain with ___ signs of infxn; and a ___ surrounded by ___ of bone on X-ray

Answer 20

bone; systemic (fever, leukocytosis); lytic focus (abscess); sclerosis (lytic focus is called sequestrum and sclerosis is called involucrum)

Question 21

Avascular (aseptic) necrosis is _____ necrosis of bone and bone marrow. Name five causes. ___ and ___ are major complications

Answer 21

ischemic; trauma, fracture (most common), steroids, sickle cell anemia, cassion disease; osteoarthritis; fracture

Question 22

____ is a benign tumor of bone. It is most commonly found on the surface of ____. It is associated with ___ syndrome.

Answer 22

Osteoma; facial bones; Gardner (familial adenomatous polyposis, fibromatosis, and osteoma of facial bones)

Question 23

____ is a benign tumor of osteoblasts (that produce osteoid) surrounded by a rim of reactive bone. Occurs in __ years of age (more commonly females/males), arises in ___ of ___ bones. Presents as bone pain that resolves with ___.

Answer 23

Osteoid osteoma; less than 25; males; cortex; long; aspirin

Question 24

Osteoblastoma vs Osteoid osteoma

Which one is >2 cm? Which one arises in vertebrae vs long bones? In which one does bone pain respond to aspirin?

Answer 24

Osteoblastoma; osteoblastoma; osteoid osteoma; osteoid osteoma

Question 25

___ is a malignant proliferation of osteoblasts. It’s peak incidence is seen in ____ and less commonly also seen in ___. It arises in ___ of long bones (usually the distal femur or proximal tibia).

Answer 25

Osteosarcoma; teenagers; elderly; metaphysis

Question 26

Name three risk factors of osteosarcoma

Answer 26

familial retinoblastoma; Paget disease; radiation exposure

Question 27

Osteosarcoma presents as a ___ or ___ with swelling. Imaging revealed a destructive mass with a ___ appearance, and lifting of the ____ (known as ____ triangle). Bx reveals ____ cells that produce ____.

Answer 27

pathologic fracture; bone pain; sunburst; periosteum; Codman; pleomorphic (variability in size/shape of nucleus); osteoid

Question 28

Ewing Sarcoma is malignant proliferation of well/poorly differentiated cells derived from _____. It arises in the ____ of long bones; usually in female/male children/adults. A ____ translocation is characteristic and it often presents locally/with metastases and is responsive/unresponsive to chemo.

Answer 28

poorly; neuroectoderm; diaphysis; male children (less than 15 yrs of age); 11;22; metastasis; responsive

Question 29

This bone tumor has an onion-skin appearance on X-ray and on bx it reveals small, round blue cells that resemble lymphocytes. It can therefore easily be confused with lymphoma or chronic osteomyeletis.

Answer 29

Ewing Sarcoma

Question 30

____ is a tumor comprised of multinucleated giant cells and stromal cells. It occurs in ___. It arises in the ____ of long bones (usually the distal femur or proximal tibia).

Answer 30

Giant cell tumor; young adults; epiphysis

Question 31

On xray, a giant cell tumor has a ___ appearance. It is locally aggressive and may recur.

Answer 31

soap bubble

Question 32

___ is a benign tumor of cartilage; ___ is a malignant cartilage forming tumor. Both arise in the ___ of bones.

Answer 32

chondroma; chondrosarcoma; medulla

Question 33

This cartilage tumor arises in the medulla of the pelvis or central skeleton.

Answer 33

Chondrosarcoma

Question 34

This cartilage tumor arises in the medulla of small bones of the hands and feet

Answer 34

Chondroma

Question 35

Which is more common, primary bone tumors or bone metastases?

Answer 35

bone metastases

Question 36

Bone mets usually result in ___ lesions, however prostate carcinoma classically produces ___ lesions.

Answer 36

osteolytic (punched out); osteoblastic lesions

Question 37

A joint is a _____. ____ joints are tightly connected to provide structural strength. ____ joints have a joint space to allow for motion.

Answer 37

connection btwn two bones; solid; synovial

Question 38

The articular surface of adjoining bones is made of ____ cartilage (type __) that is surrounded by a ____. Synovium lining the joint capsule secretes fluid rich in ____ to lubricate the joint & facilitate smooth motion

Answer 38

hyaline; II; joint capsule; hyaluronic acid

Question 39

______ is a progressive degeneration of articular cartilage (aka ____), most often due to ____. Major risk factor is ___ and others include ___ and ___. Classic presentation is ____ in the morning that gets better/worsens during the day.

Answer 39

Degenerative joint disease; osteoarthritis; wear and tear; age (common after 60); obesity; trauma; joint stiffness; worsens (different from RA)

Question 40

What is the most common types of arthritis?

Answer 40

Osteoarthritis (degenerative joint disease)

Question 41

Osteoarthritis affects a limited number of joints (oligoarticular), most commonly these 5

Answer 41

hips, lower lumbar spine, knees, DIP joints, PIP joints

Question 42

Name three pathologic features of degenerative joint disease (osteoarthritis)

Answer 42

1) disruption of cartilage that lines the articular surface (fragments of cartilage are called joint mice); 2) eburnation of the subchondral bone (bony sclerosis that occurs when bone rubs bone); 3) osteophyte formation (reactive bony outgrowths - arises in DIP (heberden nodes) and PIP (bouchard nodes)

Question 43

The hallmark of rheumatoid arthritis is ___ leading to formation of a ____. These then leads to further destruction of cartilage and ___ (fusion) of the joint

Answer 43

synovitis; pannus (inflamed granulation tissue –> bv’s, fibroblasts, and myofibroblasts that contract and fuse the joint); ankylosis

Question 44

Rheumatoid arthritis is a chronic, systemic ___ disease that classically arises in middle aged women/men. It is associated with ____. There is symmetric/asymmetric involvement of the joints Name the 5 joints commonly involved.

Answer 44

autoimmune; women; HLA-DR4; symmetric; PIP joints (swan-neck deformity), wrists (radial deviation), elbows, ankles, knees

Question 45

HLA-DR4 is associated with this disorder

Answer 45

Rheumatoid arthritis

Question 46

Which type of arthritis presents with joint stiffness in the morning? In which type does it get better with activity?

Answer 46

Osteoarthritis and RA; RA

Question 47

Name the 6 clinical features of RA

Answer 47

1) morning stiffness, improves with activity; 2) symptoms of inflammatory process (fever, malaise, weight loss, myalgia); 3) rheumatoid nodules (central zone of necrosis surrounded by epithelial histiocytes); 4) vasculitis; 5) baker cyst (swelling of bursa behind knee); 6) pleural effusions, lymph adenopathy, and interstitial lung fibrosis

Question 48

Laboratory findings for RA will show a ___ autoantibody against __ portion of ___ (rheumatoid factor). It is a marker of tissue damage and disease activity. You can also see ___ and high ___ in synovial fluid.

Answer 48

IgM; Fc; IgG; neutrophils; protein

Question 49

Complications of rheumatoid arthritis include ___ and ___.

Answer 49

anemia of chronic disease (hepcidin); secondary amyloidosis (SAA –> AA, which deposits in tissues)

Question 50

_______ are a group of joint disorders characterized by lack of rheumatoid factor, axial skeleton involvement, and a HLA-___ association. Name three

Answer 50

Seronegative spondyloarthropathies; B27; ankylosing spondyloarthritis; reiter syndrome; psoriatic arthritis

Question 51

Ankylosing spondyloarthritis involves the ___ joints and ___. It arises in young/old adults, most often female/male. It presents with ___ pain. Fusion of the ___ eventually arises (bamboo spine). Extra-articular manifestations include __ and __.

Answer 51

sacroiliac; spine; young; male; low back; vertebrae; uveitis; aortitis (leading to aortic regurgitation)

Question 52

Reiter syndrome (aka reactive arthritis) is characterized by the triad of ___, ___, and ___. Arises in young/old adults, usually females/males, weeks after a GI or ____ infxn.

Answer 52

arthritis, urethritis, conjuctivitis (can’t see, can’t pee, can’t climb a tree); young; males; chlamydia trachomatis

Question 53

Psoriatic arthritis is seen in __% of cases of psoriasis. Involves ___ and ___ joints. Most commonly affected joints are ___.

Answer 53

10; axial and peripheral; DIP joints (leads to sausage fingers or toes)

Question 54

Infectious arthritis is due to an infectious agent usually ___. Name two cause and who you see them in. Classically involves asymmetric/symmetric joint, most typically the ___. Presents as a ___ joint with limited range of motion. Also often see __, increased ___, and elevated ___.

Answer 54

bacterial; N gonorrhoeae (young adults; most common); S aureus (older children and adults; 2nd most common); asymmetric (single joint); knee; warm; fever; WBC; ESR (erythrocyte sedimentation rate)

Question 55

Gout is a deposition of ____ crystals in tissues, especially the joints due to ___. ___ is derived from purine metabolism and is excreted by the kidney. Primary gout is the most common form and the etiology of hyperuricemia is ___.

Answer 55

monosodium urate; hyperuricemia; uric acid; unknown

Question 56

Name three disorders that cause secondary gout

Answer 56

Leukemia and myeloproliferative disorders (increased cell turnover lead to hyperuricemia); Lesch Nyhan syndrome (HGPRT is used to salvage purines, and they have deficiency); Renal insufficiency (decreased excretion)

Question 57

Lesch Nyhan syndrome is an x-linked deficiency of _____, which presents with these three symptoms

Answer 57

hypoxanthine-guanine phosphoribosyltransferase (HGPRT); mental retardation, self mutilation, secondary gout

Question 58

Acute gout presents as painful arthritis of the ___ (aka ___); MSU crystals deposit in joint, and activate ___, triggering an acute inflammatory reaction. ___ or ___ may precipitate this.

Answer 58

great toe; podagra; neutrophils; alcohol; consumption of meat (lots of RNA and DNA in meat)

Question 59

Chronic gout leads to development of ___, white chalky aggregates of uric acid crystals with fibrosis and giant cell reaction in the soft tissues and joints. Can also lead to ___ due to crystals depositing in the kidney tubules

Answer 59

tophi; renal failure

Question 60

Tophi are ___, ___ aggregates of uric acid crystals with ___ and ___ reaction in the soft tissues and joints

Answer 60

white, chalky; fibrosis; giant cell

Question 61

In gout, synovial fluid shows ___ shaped crystals with positive/negative birefringence under polarized light. When laying flat the crystals appear ___.

Answer 61

needle; negative; yeLLow (lay low - also yellow in paraLLel light)

Question 62

Pseudogout, resembles gout clinically but is due to deposition of ____. Synovial fluid shows ___ shaped crystals and weakly positive/negative birefringence under polarized light.

Answer 62

calcium pyrophosphate dihydrate (CPPD); rhomboid; positive

Question 63

What is the most common benign soft tissue tumor in adults?

Answer 63

Lipoma

Question 64

What is the most common malignant soft tissue tumor in adults?

Answer 64

liposarcoma

Question 65

What is the most common malignant soft tissue tumor in children?

Answer 65

rhabdomyosarcoma

Question 66

___ is a benign tumor of adipose tissue. ___ is a malignant tumor of adipose tissue and ___ is the characteristic cell.

Answer 66

Lipoma; liposarcoma; lipoblast

Question 67

___ is a benign tumor of skeletal muscle. Cardiac ____(same as above) is associated with ____.

Answer 67

Rhabdomyoma x 2; tuberous sclerosis

Question 68

___ is a malignant tumor of skeletal muscle and ___ is the characteristic cell. On IHC staining, ___ is positive. Most common site is ____; ___ is classic site in young girls.

Answer 68

Rhabdomyosarcoma; rhabdomyoblast; desmin; head and neck; vagina (grape like mass)

Question 69

Rickets most commonly arises in children ___ years of age, and presents with these 4 findings

Answer 69

less than 1; pigeon breast deformity (inward bending of ribs with anterior protrusion of the sternum); frontal bossing (enlarged forehead - due to osteoid deposition on skull); rachitic rosary (due to deposition at costochondral junction); bowing of legs (in ambulating children)