Y2S1B3 - Path - Pathoma Msk

Front 1

Articular surface of adjoining bones is made of _ that is surrounded by a joint capsule

Back 1

hyaline cartilage (type II collagen)

Front 2

a) What mutation causes achondroplasia?

b) Most of these mutations are sporadic and are related to increased (maternal/paternal) age.

Back 2

a) activating mutation in FGFR3 (AD)

Overexpression of FGFR3 inhibits growth.

b) Paternal

Front 3

Synovium lining the joint capsule secretes fluid rich in _ to lubricate the joint and facilitate smooth motion

Back 3

hyaluronic acid

Front 4

Achondroplasia results in poor (endochondral/intramembranous) bone formation.

Back 4

Endochondral (long bones)

Intramembranous (flat bones) is not affected! This results in short extremities w/ a normal-sized head and chest.

Front 5

What is the most common type of arthritis?

What is this d/t?

Back 5

OA, osteoarthritis aka degenerative joint disease

most often due to wear and tear

Front 6

T/F

Patients with achondroplasia often have lower-than-average mental function, life span, and fertility.

Back 6

False!

None of these are affected!

Front 7

What are the risk factors for OA?

Back 7

Major is age

Others include obesity and trauma

Front 8

Osteogenesis imperfecta is most commonly due to what type of defect?

Back 8

AD defect in collagen type 1 synthesis

This is a congenital defect of bone resorption resulting in structurally weak bone.

Front 9

What joints are most commonly affected by OA?

Back 9

hips, lower lumbar, knees, and DIP and PIPs

Front 10

A young child presents with fractures to both his arms. His parents say that he fell. Bruising is not seen on physical exam. Further examination shows blue sclera. What other feature may be present in this patient or may develop later?

Back 10

This patient most likely has osteogenesis imperfecta, which can result in multiple fractures and blue sclera (thinning of scleral collagen reveals underlying choroidal veins).

Hearing loss may also present, d/t fracture of the bones of the middle ear.

Front 11

What is the classical presentation of OA?

Back 11

joint stiffness in the morning that WORSENS during the day.

Front 12

Thinning of scleral collagen in osteogenesis imperfecta can reveal what veins? (causing blue sclera)

Back 12

Choroidal veins

Front 13

Joint mice are a histological finding in what disorder?

Back 13

Osteoarthritis

Front 14

What disorder is caused by an inherited defect in bone REsorption, resulting in abnormally thick, heavy bone that fractures easily?

Back 14

Osteopetrosis

d/t poor osteoclast function

Front 15

What are some pathological features of OA? (3)

Back 15

1. joint mice - disruption of cartilage lining articular surface

2. eburnation of subchondral bone

3. osteophyte formation - classically seen in DIP and PIP

Front 16

Multiple genetic variants of osteopetrosis exist, but what mutation can lead to loss of the acidic microenvironment? What is this environment needed for?

This mutation is also a/w what clinical feature?

Back 16

Carbonic anhydrase II mutation. Acidic microenvironment is needed for bone resorption - needed to remove Ca2+ from bone during resorption (like cola poured in pipes)

Renal tubular acidosis! lack of CA results in decreases tubular reabsorption of HCO3-, leading to metabolic acidosis

Front 17

_ is a chronic, systemic autoimmune disease classically seen in middle aged women

Back 17

Rheumatoid arthritis

Front 18

A patient presents with a history of multiple bone fractures, anemia, thrombocytopenia, and leukopenia with extramedullary hematopoiesis, vision and hearing impairment, hydrocephalus, and renal tubular acidosis.
What is the tx for this disorder?

Back 18

Bone marrow transplant (treats osteopetrosis b/c osteoclasts, which are basically bone macrophages, are derived from monocytes from the bone marrow)

Front 19

RA is associated with _

Back 19

HLA-DR4

Front 20

What causes each of the following clinical features in ostepetrosis?

a) anemia, thrombocytopenia, and leukopenia w/ extramedullary hematopoiesis
b) vision/hearing impairment
c) hydrocephalus
d) renal tubular acidosis

Back 20

a) bony replacement of marrow (myelophthisic process)
b) impingement on cranial nerves
c) narrowing of foramen magnum
d) carbonic anhydrase II mutation (decreased tubular reabsorption of bicarb, leading to metabolic acidosis)

Front 21

What is the hallmark of RA?

Back 21

Synovitis leading to the formation of a pannus (inflammed granulation tissue)

Front 22

Middle-aged adult patient presents with hip fracture from minor fall. Lab findings show decreased serum calcium and phosphate and increased PTH and alkaline phosphatase. What disorder is likely?

Back 22

Osteomalacia (low Vit D in adults)

inadequate mineralization leads to weak bone and increased risk for fracture (especially weight-bearing areas)

Front 23

RA eventually leads to destruction of _ and _ of the joint

Back 23

cartilage

akylosis (fusion)

Front 24

6 mo old patient presents with pigeon-breast deformity, frontal bossing, and rachitic rosary. What feature may be present in a child who is able to walk with the same disorder?

Back 24

Bowing of the legs

This is Rickets (low vitamin D in children)
frontal bossing is d/t osteoid deposition on skull and rachitic rosary is osteoid deposition at costochondral junction

Front 25

What is the classical presentation of RA?

Back 25

Morning stiffness that IMPROVES with activity

Front 26

Vitamin D is normally derived from skin exposure to sun (85%) and diet (15%).

Why might vitamin D deficiency be seen in liver or renal failure?

Back 26

b/c activation requires 25-hydroxylation by the liver followed by 1-alpha-hydroxylation by the proximal tubular cells of the kidney

Front 27

What joints are typically involved with RA?

Back 27

SYMMETRICAL involvement of:

PIP (swan neck), wrists, elbows, ankles, and knees.

Note: NOT DIP

Front 28

Osteoblast activity is a/w (decreased/increased) alkaline phosphatase.

Back 28

Increased

Front 29

What are x ray findings of RA?

Back 29

joint space narrowing, loss of cartilage, osteopenia

Front 30

Active Vitamin D raises serum calcium and phosphate by acting on what 3 tissues?

Back 30

Intestine - inc absorption of calcium and phosphate
Kidney - inc reabsorption of calcium and phosphate
Bone - inc resorption of calcium and phosphate

Front 31

What are symptoms other than joint pain classically seen in RA?

Back 31

fever, malaise, weight loss, myalgias, Rheumatoid nodules, Vasculitis, Baker's cyst, pleural effusions, lymphadenopathy, and interstitial lung fibrosis

Front 32

Risk of osteoporosis is determined by what 2 factors?

Back 32

Peak bone mass - achieved by 30 yrs and is based on genetics (vit D receptor variants), diet, and exercise.

Rate of bone loss thereafter - slightly less than 1% is lost each year; lost more quickly w/ lack of weight-bearing exercise (space travel), poor diet, decreased estrogen (menopause)

Front 33

What are the characteristics of rheumatoid nodules?

Back 33

Rheumatoid nodules arise in skin and visceral organs and are characterized by a central zone of necrosis surround by epitheloid histiocytes.

Seen in RA

Front 34

Postmenopausal women presents with back pain, kyphosis, and fracture of the distal radius. All labs are normal.

What do you suspect?

Back 34

Osteoporosis

(bone pain and fractures in weight-bearing areas such as vertebrae, hip, and distal radius; abnormal labs rule out osteomalacia)

Front 35

What is the classic laboratory finding associated with RA?

Back 35

IgM autoantibody against Fc portion of IgG ...this is called Rheumatoid factor (a marker of tissue damage and disease activity)

Also see neutrophils and high protein in synovial fluid

Front 36

What are possible tx's for osteoporosis?

What is CI?

Back 36

Exercise, vitamin D, calcium - limit bone loss
Bisphosphonates - induce apoptosis of osteoclasts
Estrogen replacement is controversial (currently not recommended

CI - glucocorticoids!

Front 37

_ are a group a joint disorders characterized by a lack of rheumatoid factor, axial skeleton involvement, and HLA-B27 involvement

Back 37

Seronegative Spondyloarthropathies

Front 38

A 65 yo patient presents with complaints of pain in the skull and an increasing hat size. You also find that they have some hearing loss and lion-like facies. Labs show isolated elevated alkaline phosphatase.

What can you treat them with?

Back 38

This is Paget disease

Calcitonin (inhibits osteoclast function)
Bisphosphonates (induces apoptosis of osteoclasts)

Paget is usually seen in late adulthood (>60), possibly viral, is an imbalance between osteoclast and osteoblast function, and is a localized process involving one or more bones. skull is commonly affected. bone pain d/t microfractures.

Front 39

Anklosing spondyloarthritis involves the _ and _. It typically arises in what group?

Back 39

sacroiliac joints and spine.

Arises in young, male adults

Front 40

What is the MC cause of isolated elevated alkaline phosphatase in patients >40 years old?

Back 40

Paget Disease

Front 41

A 22 yo male presents with low back pain and vision changes. Upon PE, you note his eyes are red, Xray of lumbar spine shows fusion of vertebrae, or "bamboo spine". What is the dx?

Back 41

Ankylosing spondyloarthritis.

In addition to red eyes (uveitis), pt is at risk for aortitis, which could eventually lead to aortic regurgitation and an increased risk of aneurysms.

Front 42

What are the 3 stages of Paget Dz?

Back 42

1. osteoclastic
2. mixed osteoblastic-osteoclastic
3. osteoblastic

end result: thick, sclerotic bone that fractures easily

Front 43

Pt complains of joint pain, painful urination, and vision difficulties. What is the likely dx?

Back 43

Reiter Syndrome
"Can't see, can't pee, can't climb a tree"
this is a seronegative spondyloiarthropathy.

Front 44

Bone biopsy that shows a mosaic pattern of lamellar bone is indicative of what?

Back 44

Paget Disease

cement lines that haven't been sealed, looks like puzzle pieces

Front 45

Pt complains of joint pain, painful urination, and vision difficulties.They were seen a few weeks ago by another physician. What is the likely pathogen that caused the initial infection?

Back 45

Chlamydia trachomatis

First of all, know this is describing Reiter Syndrome, which classically arises in young males weeks after a GI or chylamydia trachomatis infection

Front 46

What are possible complications of Paget?

Back 46

High-output cardiac failure (d/t formation of AV shunts in bone and heart has to push through them)

Osteosarcoma (osteoblasts can mutate and develop malignancy)

Front 47

_ is seen in 10% of cases of psoriasis. It involves axial and peripheral joints, _ joints of hands and feet are most commonly affected, leading to "sausage" fingers and toes

Back 47

Psoriatic arthritis


DIP joints

Front 48

In osteomyelitis,

a) Children typically have _______ bacteremia that seeds the ________.

b) Adults typically have ________ bacteremia that seeds the __________.

Back 48

a) transient, metaphysis

b) open-wound, epiphysis

Front 49

Sausage fingers and toes are commonly associated with what disorder?

Back 49

Psoriatic arthritis,

a seronegative spondyloarthropathy

Front 50

What is the MC organism for osteomyelitis?

And in each of the following concurrent situations?
a) sexually active, young adults
b) sickle cell dz
c) diabetics or IVDA
d) cat or dog bites/scratches
e) vertebral involvement (Pott dz)

Back 50

Staph aureus

a) N gonorrhoeae
b) Salmonella
c) Pseudomonas
d) Pasteurella
e) myco TB

Front 51

What are the 2 most common causes of infectious arthritis?

Back 51

N gonorrhoeae - MC!

S aureus

Front 52

A child presents with bone pain, fever, and leukocytosis. X-ray shows a lytic focus (absceess) surrounded by sclerosis of bone. What test should you run to make your dx?

Back 52

Blood culture (this is for osteomyelitis)

Lytic focus is called sequestrum and sclerosis is called involucrum

Front 53

How does an infectious arthritis present?

Back 53

Classically involves a single joint, usually the knee. Presents as a warm joint with limited ROM, fever, increased WBC, and elevated ESR

Front 54

What are some possible causes of avascular (aseptic) necrosis, which is an ischemic necrosis of bone and bone marrow?

Back 54

traumar or fracture (MC)
steroids (increase the risk)
sickle cell anemia (vasocclusive crisis)
Caisson disease (gas emboli, especially N2)

Osteoarthritis and fracture are major complications d/t necrosis

Front 55

_ is characterized by monosodium urate cytstal deposition in tissues, particularly the joints

Back 55

Gout

Front 56

The combination of familial adenomatous polyposis, fibromatosus in retroperitoneum, and osteoma of facial bone is what syndrome?

Back 56

Gardner syndrome

Osteomas most commonly arise on surface of facial bones and are benign.

Front 57

Gout is d/t _.

Back 57

hyperuricemia.

Uric acid is derived from purine metabolism

Front 58

A young adult male (23 yo) presents with back pain. He claims that aspirin does not help with his symptoms. X-ray reveals a 3 cm bony mass with a radioluscent core.

What is your dx?

Back 58

Osteoblastoma

Front 59

Secondary gout is seen with _ and _ disorders

Back 59

leukemia and myeloproliferative disorders

- increased cell turnover leads to hyperuricemia bc lots of nucleic acids (ie purines) are being broken down

Front 60

A young adult male (23 yo) presents with pain in the middle of his thigh. He claims that aspirin helps relieve pain. X-ray reveals a 1 cm bony mass with a radioluscent core.

What is your dx?

Back 60

Osteoid osteoma

Front 61

Secondary gout is seen in _ syndrome and _ insufficiency

Back 61

Lesch - Nyhan syndrome


Renal insufficiency

Front 62

A benign tumor of osteoblasts (that produce osteoid) surrounded by a rim of sclerotic, reactive bone is what type of tumor?

Which part of the bone do these normally arise?

Back 62

Osteoid osteoma (or osteoblastoma?)

Cortex of long bones (diaphysis), such as femur

Front 63

Lesch Nyhan syndrome is a _ deficiency of _. These patients present with _ and _

Back 63

X linked deficiency of Hypoxanthine-guanine phosphoribosyltransferase (HGPRT),.

Presents with mental retardation and self mutilation

Front 64

What is the MC benign tumor of bone?

Back 64

Osteochondroma

Front 65

_ or _ consumption may precipate an episode of gout

Back 65

Alcohol or red meat
(shell fish)

Front 66

Name the bone tumor with an overlying cartilaginous cap that arises from a lateral projection of the growth plate (metaphysis).

Back 66

Osteochondroma

The bone is continuous with the marrow space and the overlying cartilage can transform (rarely) to chondrosarcoma.

Front 67

Chronic gout leads to development of _, and _

Back 67

development of tophi (white chalky aggregates of uric acid crystals with fibrosis and giant cell rxn)

and Renal Failure (urate nephropathy)

Front 68

A child with bilateral retinoblastoma has a higher chance of also developing what other tumor?

Back 68

Osteosarcoma (b/c of familial retinoblastoma)

Front 69

Synovial fluid seen in a gouty attack shows _ with _ appearance under polarized light

Back 69

needle shaped crystals

negative birefringence (when crystals lay low (flat) they are yellow)

Front 70

Incidence of osteosarcoma peaks in what ages?

Back 70

Peaks in teens, less commonly in elderly

Front 71

Pseudogout is deposition of _ crystals.

Synovial fluid shows _ shaped crystals with _ appearance under polarized light

Back 71

Calcium pyrophosphoate dihydrate (CPPD)

rhomboid shaped crystrals with weakly positive birefringence

Front 72

Bone biopsy that reveals pleomorphic cells that produce osteoid is the hallmark of what?

Back 72

Osteosarcoma

Front 73

A teenager presents with bone pain and swelling in the knee region. Imaging reveals a destructive mass in the distal femur with a "sunburst" appearance and lifting of the periosteum (Codman triangle). What is this? Where does it arise?

Back 73

Osteosarcoma - a malignant proliferation of osteoblasts

arises in metaphysis of long bones, usually distal femur or proximal tibia (knee region)

risk factors include familial retinoblastoma, Paget disease, and radiation exposure.

Front 74

A young adult presents with a bony mass with "soap-bubble" appearance on imaging. Where does this type of tumor arise in the bone?

Back 74

This is a giant cell tumor (comprised of multinucleated giant cells and stromal cells) and arises in the epiphysis of long bones (knee region usually). This is the ONLY bone tumor that arises from the epiphysis!!

It is locally aggressive and may recur.

Front 75

A male child, 14 yo (<15 yo) has a biopsy of the femur that reveals small, round blue cells that resemble lymphocytes.

What dz's will be on your differential? How can you determine if this is a bone tumor?

Back 75

Lymphoma, chronic osteomyelitis, and Ewing sarcoma

Ewing sarcoma will have a (11;22) translocation!!

Front 76

"Onion-skin" appearance on x-ray is a/w what bone tumor?

Back 76

Ewing sarcoma

Arises in diaphysis of long bones, usually in male children <15 yo. Often presents w/ metastasis and responds well to chemo.

Front 77

Ewing sarcoma is a malignant proliferation of poorly-differentiated cells derived from what cell type?

Back 77

Neuroectoderm

Front 78

Cartilage tumors arise where in the bone?

What bones do benign vs malignant tumors arise in?

Back 78

Medulla

Benign - small bones of hands and feet
Malignant - pelvis or central skeleton

Front 79

What type of lesions do metastatic tumors usually result in?
What's the exception?

Back 79

Osteolytic (punched-out) lesions

Prostatic carcinoma classically causes osteoblastic lesions (sclerotic)

Front 80

Some cases of dermatomyositis are a/w carcinoma, especially which type?

Back 80

Gastric carcinoma

Front 81

A patient presents complaining that they can't comb their hair and they can't climb the stairs. On physical exam, you see a rash on the upper eyelids (heliotrope rash) and malar rash. There are also red papules on the elbows, knuckles, and knees. Lab results show increased CK, positive ANA and anti-Jo-1 antibody.
How do you treat this patient?

Back 81

Corticosteroids

This is dermatomyositis! bilateral proximal muscle weakness, distal involvement can develop later in dz. re papules are called Grotton lesions. Anti-Jo-1 antibody is hallmark and distinguishes from SLE, which would be positive for dsDNA.

Front 82

Dermatomyositis has (endo/peri)-mysial inflammation with _________ on biopsy.

Back 82

perimysial (CD4+) -> remember b/c closer to edge/skin
perifascicular atrophy

Front 83

Polymyositis has (endo/peri)-mysial inflammation with _________ on biopsy.

Back 83

endomysial (CD8+)
necrotic muscle fibers

Otherwise, polymyositis resembles dermatomyositis except it doesn't involve the skin

Front 84

X-linked muscular dystrophy is a degenerative disorder characterized by muscle wasting and replacement of _________ by __________. It is due to mutations in what?

Back 84

skeletal muscle by adipose tissue

Dystrophin - important for anchoring the muscle cytoskeleton to the ECM

Front 85

Why are the mutations in X-linked muscular dystrophy often spontaneous?

Back 85

D/t it's large gene size, which predisposes to a high rate of mutation

Front 86

Why does Becker muscular dystrophy result in a milder form of the disease than Duchenne muscular dystrophy?

Back 86

B/c it is d/t mutated dystrophin instead of DELETION of dystrophin in Duchenne

Front 87

How does Duchenne muscular dystrophy present?

How does death result?

Back 87

Proximal muscular weakness at 1 yr of age, progresses to involve distal muscles
Calf pseudohypertrophy
Serum CK elevated

Death from cardiac or respiratory failure (myocardium MC)

Front 88

Calf pseudohypertrophy is a characteristic finding of what disorder?

Back 88

Duchenne muscular dystrophy, b/c at 1 when they get proximal muscle weakness, they are learning to walk and the calves have more forxe on them. Later, the distal involvement converts the calves to fat.

Front 89

A woman presents with muscle weakness that worsens with use and improves with rest. She has ptosis and diplopia.
a) What is the likely cause for this disease?
b) Symptoms will improve with tx with what?

Back 89

Myasthenia Gravis

a) autoantibodies against the postsynaptic Ach receptor at NMJ
b) Acetylcholinesterase agents. Unless she has thymic hyperplasia or a thymoma, in which case a thymectomy will improve symptoms!

Front 90

Lambert-Eaton arises as a paraneoplastic syndrome, most commonly d/t what type?

Back 90

Small cell carcinoma of the lung.

Symptoms resolve with resection of the cancer, NOT with anticholinesterase agents.

Front 91

A disorder that produces antibodies against presynaptic calcium channels of the NMJ leads to impaired Ach release (b/c firing of presynaptic calcium channels is required for Ach release). Patients present with proximal muscle weakness that IMPROVES with use and the eyes are usually spared.
What is the dz?

Back 91

Lambert-Eaton syndrome

Front 92

What are the MC benign and malignant soft tissue tumors in adults?

Back 92

Benign - Lipoma
Malignant - Liposarcoma

Front 93

Lipoblasts are the characteristic cell of what tumor?

Back 93

Liposarcoma

Front 94

What is cardiac rhabdomyoma a/w?

Back 94

tuberous sclerosis

rhabdomyoma is a benign tumor of skeletal muscle

Front 95

What is the MC malignant soft tissue tumor in children?

Back 95

Rhabdomyosarcoma

Front 96

A mass from the vagina of a 5 yo girl that has rhabdomyoblasts and is desmin positive is likely what tumor?

Back 96

Rhabdomyosarcoma

head and neck MC, but vagina is the classic site in young girls around 5!!