MSK/Derm (U.W.)

Question 1

Leukocyte Adhesion Deficiency

Answer 1

s(x)- recurrent infections, especially S. aureus, without purulence
- might notice CD18 missing from leukocyte surfaces. causes no integrin formation, so leukocyte can’t migrate causing leukocytosis

Question 2

what connects osteocytes?

Answer 2

• gap junctions

- allows osteocytes to communicate with bone surface and regulate bony remodeling

Question 3

eczema dermatitis treatment with corticosteroid causes what side effect

Answer 3

dermal atrophy due to decrease production of ECM and GAGs

Question 4

what can augment azathioprine’s action?

Answer 4

ALLOPURINOL

azathioprine can be inactivated by Xanthine Oxidase. Xanthine Oxidase inhibitor Allopurinol can therefore increase Azathioprine being converted to ACTIVE metabolites, by blocking the inactivating pathway

Question 5

Pirimformis Syndrome

Answer 5

Piriformis M goes through greater sciatic foramen, inferiorly in the greater sciatic foramen, the sciatic n also passes.
s(x)- pain on buttock and posterior thigh
pain upon external rotation of extended thigh and abduction of flexed thigh

Question 6

mosaic pattern with prominent cement lines accompanied by bony pain is what disease?

Answer 6

Paget’s

Question 7

thymus is derived from what? what other structure has the same derivative?

Answer 7

3rd pharyngeal pouch

inferior parathyroid glands

Question 8

where do you give an intragluteal injection

Answer 8

anterolateral preferred, if not, then superolateral

Question 9

injection in which quadrant affects the superior gluteal N

Answer 9

superomedial

Question 10

injection in which quadrant affects the sciatic N

Answer 10

superomedial, inferomedial and lateral

Question 11

blood supply to femoral head

Answer 11

medial circumflex A

Question 12

Falling onto an outstretched arm, aka hyperextension injury often causes what?

Answer 12

supracondylar fracture

Question 13

anterolateral displacement of supracondylar fracture injures?

Answer 13

radial N

Question 14

anteromedial displacement of supracondylar fracture injures?

Answer 14

median N and brachial A

Question 15

what type of HS response in MG

Answer 15

Type II- antibody mediated

Question 16

Osgood Schattler Disease

Answer 16

Repeated quads contraction and growth spurt can cause patellar tendon to separate from TIBIAL TUBERCLE causing a secondary ossification center and focal pain there, with pain on extension

Question 17

Nursemaid’s Elbow

Answer 17

Radial head subluxation (aka no longer interacting at elbow joint) bc of pulling force on arm causing annular ligament to be displaced/torn.
*hints- child< 5yo, holds arm tightly to body, refuses to flex elbow

Question 18

most common cause of axillary N injury

Answer 18

anterior shoulder displacement

Question 19

patellar fracture causes what movement problem

Answer 19

knee extension

Question 20

what artery runs with the Radial N

Answer 20

Deep Brachial A

Question 21

what artery runs with the Axillary N

Answer 21

PCHA

Question 22

empty can test (abduct arm 90 degree, flex 30 deg, thumbs to the floor, resistance from above arm) tests integrity of what muscle

Answer 22

suprapinatus

Question 23

Xeroderma Pigmentosa

Answer 23

Autorecessive mut in nucleotide excision repair, usually due to endonuclease defect

Question 24

Chediak Higashi

Answer 24

oculocutaneous albinism + immunodeficiency + neuro symptoms ( nystagmus/ CN defects)

• defect in neutrophil phagosome lysosome function
• findings: giant lysosomal inclusions

Question 25

what is the pathophysiology of scurvy

Answer 25

vit C deficiency Vit C needed for post translation modification of collagen occuring at RER , specifically hydroxylation of proline and lysine residues that contribute to strength

Question 26

Alkaptonuria? - cause - symptoms - findings

Answer 26

- autosomal recessive deficiency in homogentisic acid dioxygenase (step in tyrosine metabolism) causes a build up of homogentisic acid, which accumulates in connective tissue/bone - blue/black spots in sclera and auricular cartilage; arthritis in spine/joints, black urine

Question 27

what does ATP binding to myosin cause

Answer 27

detachment of myosin head from actin filament (note this is NOT the power stroke!!)

Question 28

appropriate way to start treatment for Rheumatoid Arthritis?

Answer 28

- induction with glucocorticoid (prednisone) or NSAID | - also start DMARDs (MTX, sulfasalazine tnfa) but these take weeks to kick in

Question 29

t(x) for dermatophytosis ?

Answer 29

Terbinafine- blocks squalene epoxidasethereby inhibiting ergosterol synthesis

Question 30

ecthyma gagrenosum

Answer 30

pseudomonas aeruginosa

Question 31

Thoracic Outlet Syndrome

Answer 31

Ulnar impingement/lower plexus symptoms (pinky is tingly/numb) + pain/ parasthesia/edema due to subclavian A/V and brachial plexus impingement **hint: often an extra RIB is mentioned hint- often due to overhead injury like pitching

Question 32

leukocytoclastic vasculitis

Answer 32

non-blanching palpable purpura on lower extremities following drug interaction (penicllin, cephalosporins) cause: cutaneous small vessel vasculitis

Question 33

Polyarteritis Nodosa

Answer 33

segmental, transmural inflammation of artery wall - often causes GI ischemia, and ischemia of other organs- excluding lungs idiopathic, but STRONG RELATION TO HEP B

Question 34

antibodies against desmosomes

Answer 34

pemphigus vulgaris

Question 35

antibodies against hemidesmosomes

Answer 35

bullous pemphigoid

Question 36

graft v host disease

Answer 36

seen in tissue donations that has high concentration of lymphocytes (Liver, bone marrow). Tcell of the graft attack host MHC antigens

Question 37

pellagra

Answer 37

``` vit B3 (niacin) deficiency 3D's: diarrhea, dementia, dermatitis - without NAD, isocitrate dehydrogenase, malate dehydrogenase, and alphaketoglutarate dehydrogenase will not function ```

Question 38

Giant Cell Arteritis is mediated by?

Answer 38

cytokines, specifically IL6

Question 39

grotton papule

Answer 39

dermatomyositis

Question 40

Ehlers Danlos

Answer 40

defect in Procollagen Peptidase. Procollagen peptidase cleaves procollaged N and C terminals to make tropocollogen (in ECM) if these N and C terminals are not cleaved, the procollagen remains SOLUBLE and is not able to crosslink

Question 41

what type of sweat gland is involved in acne vulgaris

Answer 41

sebaceous sweat glands, which are holocrine sweat glands

Question 42

osteogenica imperfecta

Answer 42

autosomal dominant mutation is type 1 collagen (found in osteoid)

Question 43

poison ivy pathophysiology

Answer 43

urushiol is the toxin, it conjugates with hapten (a peptide). once presented on MHCI and II cells it elicits hapten sensitive T cells to proliferate. CD8+ T cells then kill all keratinocytes expressing hapten causing the blistering

Question 44

initial testing for GCA suspicion

Answer 44

ESR and CRP .. then temporal artery biopsy to confirm

Question 45

Dermatitis Herpetiform pathophys and association

Answer 45

- self reactive IgA against gliadin crossreacts with epidermal gliadin - assn- Celiac's

Question 46

action of latissimus dorsi

Answer 46

extension, adduction, and internal rotation of arm

Question 47

why is raloxifene better than tamoxifen for osteoporosis

Answer 47

tamoxifen can cause estrogen agonist effects on the uterus causing endometrial hyperplasia/cancer where as raloxifene has estrogen antagonist activity on the uterus

Question 48

clinical use of calcipotriene, calcitriol, and tacalcitol ?

Answer 48

psoriasis Vit D analogs inhibit keratinocyte proliferation and stimulate keratinocyte differentiation remember vitamin D is a nuclear transcription factor

Question 49

McCune Albright Syndrome clinical symptoms

Answer 49

large cafe au lait spots, fibrous dysplasia (osteolytic bone lesions), and endocrine abnormalities(like puberty before 7) = Mccune albright

Question 50

McCune Albright pathogenesis

Answer 50

somatic mosaicism causing mutation in GNAS gene--> constitutively active alpha subunit of Gprotein/adenylate cyclase/CAMP

Question 51

acute rheumatic fever cause of death

Answer 51

pancarditis

Question 52

mode of diagnosing osteomyelitis

Answer 52

blood cultures | MRI of spine-most sensitive

Question 53

dystrophin role

Answer 53

- linker protein that makes sarcolemma stable | - connects cytoskeleton (actin) to transmembrane proteins

Question 54

Muscular Dystrophy- duchenne and becker

Answer 54

Xlinked recessive myopathy due to frameshift deletion of dystrophin -gower's sign - muscle filled with fat (psuedohypertrophy) (note becker's MD is similar but is not a frameshift deletion, just a frameshift truncation, so less severe)

Question 55

Stewart-Treves Syndrome

Answer 55

cutaneous angiosarcoma (a misnomer because it is a sarcoma of lymph).usually following a lymphnode dissection.

Question 56

where does osteomyelitis affect children?

Answer 56

-METAPHYSIS of long bone because slower moving blood and fenestration is ideal for infection