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Flashcards in MSK/rheum Deck (173):
1

Elderly pt with bullae. Histopathology with linear immunofluorescence at the dermal-epidermal junction

Bullous pemphigoid (BP)
Autoimmune attack against hemidesmosomes

2

Pathophysiology of Guillain-Barre (even if it follows gastroenteritis)

Autoimmune disorder against peripheral nerves and Schwann cells.
Histology = perivenular and endoneurial infiltration with lymphocytes, Macrophages, and plasma cells
Symmetrical ascension

3

Pt unable to raise left arm. Leaves arm hanging at his side with forearm pronated

Erb palsy "waiters tip"
Upper trunk lesion
Affected muscles: abductors (deltoid, supraspinatus), lateral rotators (infraspinatus), and biceps

4

Pt with dysphagia, claw like hand due to tightened skin, small flat red skin marks, Subq nodules, with significant cold sensitivity in her hands

CREST Syndrome, varient of scleroderma
Calcinosis (skin nodules)
Raynaud phenomenon
Esophageal dysfunction
Sclerodactyly (skin thickening)
Telangiectasis (small red marks from dilated vessels
Anticentromere antibodies

5

Pt falling on outstretched hand, anterior shoulder dislocation likely

Axillary n. injury, inn deltoid. thus unable to abduct the shoulder

6

Pt that can't lift arm the first 15 degrees of abduction

Supraspinatus injury
Pt may comment that they can lift arm after passing the 15 degree point

7

infant with lethargy, FTT, fever, increased head circumference, prominent hepatosplenomegaly with profound anemia and leukopenia. Autopsy shows infiltration of the medullary canal space by bony spongiose tissue

osteopetrosis
failure in bone remodeling due to osteoclast malfunction. medullary canal is replaced by bony matrix (loss of hemopoeitic material) and pts rely on extramedullary hematopoeisis. bone becomes brittle. AD version is more benign

8

function of isoniazid

prophylactic TB med following +PPD but - CXR. decreases synthesis of mycolic acids.
can cause drug induced SLE (anti histone Ab)

9

HLA type associated with RA and DM

HLA-DR4

10

HLA associated with akylosing spondylitis, post gonococcal arthritis, acute anterior uveitis

HLA-B27

11

HLA associated with Graves dz

HLA-B8

12

HLA associated with kawasaki dz

HLA-BW22

13

HLA associated with chronic active hepatitis, sjogren syndrom and T1DM

HLA-DR3

14

appearance of gout aspirate

negatively birefringent crystals

15

ca, phosphate, and alk phos in a pt with paget bone dz

nl ca, phos
high alk phos

16

which muscle opens the jaw?

lateral pterygoid. inn by V3

17

in a region of high prevalence what happens to PPV and NPV

PPV increases
NPV decreases

18

pt with fatigue, headache, and blurry vision. can also have fever and jaw pain

temporal (giant cell) arthritis
tx with corticosteroids

19

40-60yo pt with flaccid blisters that rupture leaving painful raw spots.

pemphigus vulgaris
autoimmune against desmoglein 3 in the desmosome and macula adherins (attaches epithelial cells together)
can be lethal
tx - corticosteroids

20

if a kid punches a wall and fractures his hand he probably broke which bone?

metacarpals "boxers fracture"

21

Mechanism of action of Tacrolimus

post transplant immunosuppresant
Inhibits calcineurin - inhibits T lymphocyte signaline

22

Test used to dx myasthenia gravis? Potential complication?

Test - ACh receptor Ab
Complication - thymomas (widened mediastinum)
tx - AChEI (pyridostigmine)

23

In long bone ossification

endochondral ossification = osteoblasts secrete osteoid over a hyaline cartilage model (woven bone)

24

Pt with fractures with a CBC showing:
elevated Calcium
Low Phosphate
High Alk phos

osteitis fibrosa cystica, a complication of untreated hyperPTH (too much reasorption, brown tumor in bone)

25

Pt with bone dz and:
NL calcium
NL Phosphate
High Alk Phos

Paget dz
Overactivity of clasts and blasts with sclerotic and lytic lesions on CXR

26

Desmosomes are joined by

Tight junctions

27

Lab finding in a patient with sausage like fingers and a scaly rash

Psoriatic arthritis
Elevated ESR

28

Underlying genetic cause of achondroplasia

Defect in Fibroblast growth factor receptor 3 (FGFR3)
AD

29

Polymyalgia rheumatica is closely associated with?

Giant cell Arthritis (Temporal Arthritis)

30

common complications of ankylosing apondylitis

uveitis
aortic regurgitation

31

pt that has difficulty standing, walking up stairs, or jumping following a posterior hip location damaged which nerve?

inferior gluteal n.
inn gluteus maximus

32

pt falling on outstretched hand with pain in snuff box but negative XR likely has?

scaphoid fx
pain on lateral wrist on dorsiflexion and abduction
bone will undergo avasculaf necrosis and will be hypodensd on depeat XR

33

if a pt leaves a mid shaft humoral fracture that is displaced go untreated they risk losing function of?

muscles inn by the radial n.: brachioradialis

34

if a pt has hoarsness following a thyroidectomy which branchial sturctures may have been damaged?

branchial arch 4 - laryngeal n.
branchial arch 6 - recurrent laryngeal n.

35

what type of tissue arises from branchial:
groove
arch
pouch

groove = ectoderm
arch = mesoderm
pouch = endoderm

36

in erb-duchenne which muscles are affected?

biceps, deltoid, infraspinatus, supraspinatous
c5-c6

37

kid with leg pain and intermittent fevers. bx shows uniform cells with scant clear cytoplasm and no evidence of normal bony matrix

ewing sarcoma
anaplastic small blue cells
onion skin lesion on XR
t11;12 translocation

38

pt rolls ankle inward and presents with forward displacement of talus likely injured which ligament?

anterior talofibular ligament
most common lateral ligament injury of the foot because it is the weakest

39

muscles that elevate the pharynx are derived from which embryological structure?

branchial arch 3 - stylopharyngeus m. (CN IX)
branchial arch 4 - levator veli palatini m. (CN X)

40

following statin initiation, pt presents with increased BUN, creatanine, and tea colored urine due to?

acute tubular necrosis secondary to myoglobin release from rhabdomyolysis.

41

young male pt presents with leg pain and a fhx of sister with eye cancer. bx receals malignant bone dz

osteosarcoma
metaphyseal region of long bone
XR = sunburst pattern
associated with Rb mutation

42

30-60 yesr old male with cancer in the pelvis, spine, scapula, humerus, tibia, or femur

chondrosarcoma

43

older male pt with pelvic pain and XR demonstrating blastic lesions

metastatic cancer secondary to prostate cancer
osteolytic lesions = colorectal

44

direct inguinal hernias pass through x and are bordered by

protrude through hasselbach triangle (which can include through the external inguinal ring)
border = inguinal ligament (inferior), rectus abdominous medially, and inferior epigastric vessels laterally

45

indirect inguinal hernias pass through x and are bordered by

pass through internal inguinal ring (patent processus vaginalis) and enter scrotum

46

pt with recent allergies, asthma, uveitis, mild hearing loss, parathesia, diffuse joint pain, weak DTR, and eosinophilia

churg-strauss
check p-anca

47

slashing the medial aspect of the wrist may damage the?

ulnar n.
adductor pollicis m.
may have a claw hand

48

man lifts a box over his head and tears a muscle. has weakness on medial rotation of the arm. pt likely injured his

subscapularis m.

49

sle patient that also has a positive VDRL likely has?

anti-smith ab
this is an autophospholipid ab that reacts to cardiolipin
ana = sensitive to sle
anti-smith and anti-dsdna ab = specific for sle

50

pt with muscle weakness and heliotrope rash

defmatomyositis
anti-jo1 ab

51

a pt with gastritis that is requesting a medication to control his pain secondary to osteoarthritis should receive

celecoxib
cox 2 inhibitor Vijds exacerbation of gastritis

52

what are the steps in smooth muscle contraction

AP activates voltage gated calcium channels
calcium binds calmodulin and activates myosin light chain kinase
mlck phosphorylates myosin allowing it to crossbridge with actin

53

what nerve and muscle can be injured following a mastectomy causing winging of the scapula?

serratus anterior m.
long thoracic n. (c5, c6, c7)

54

which drugs are used in chronic gout by competing with uric acid for resorption in the kidney

probenecid, sulfinpyrazone

55

what drug is used in acute gout by limiting the inflammatory response to urate crystals

colchicine

56

in ortner syndrome, the left atrium produces hoarseness by compressing?

the left recurrent layngeal n. a branch of the vagus n.

57

following a humoral fracture a pt may have difficulty with which motion?

extending the wrist, forearm supination
decreased brachilradials reflex
radial n. damage

58

in carpal tunnel syndrome
which nerve is compressed ?
which fingers become weak?
sensation can be list where?

median n. compression
thumb weakness
loss of sensation over palmar aspect of second digit

59

in complete thrombosis of the radial a., which vessels can provide collateral flow in the hand?

arteries of the deep and superficial palmar arch

60

a baseball pitcher is unable to laterally rotate his arm most likely injured his?

infraspinatus m.

61

in the second phase of pager dz, how does the pts levels of ca, alk phos, and phos change?

stage 2= mixed period of bone formation
nl phos
nl to slightly elevated ca
alk phos high (400ish)

62

following treatment for a fungal skin infection a pt has hyperpigmentation. which drug was used?

ketoconazole
occurs due to desmolase inhibition causes decreased levels of cortisol and melanocyte stimulating hormone loses its feedback inhibition

63

an epileptic pt receives treatment and weeks later presents with stevens-johnson syndrome. what is the drug?

lamotrigine
alsophenytoin, ethosuximide, carbamazapine

64

appendicitis symptoms will follow which dermatomal distribution?

T10, T12
T10 controls the belly button (but ten)

65

a pt undergoing a muscle stimulation test that improves after repeat stimulation

Lambert eaton syndrome
ab against presynaptic ca channels

66

the cremaster m. is formed from the?

internal oblique m.

67

in a pt with OA what structural changes might you expect on histology of the joint space?

dislodged pieces of cartilage and subchondral bone

68

what mutation is found in becker muscular dystrophy

in frame deletion
these guys have the weakness symptoms, but do not have intellectual disabilities

69

what mutation is found in duchenne muscular dystrophy?

out of frame deletion. truncated protein

70

inheritance pattern through maternal mitochondria

heteroplasmy

71

hx of seizures and ragged muscle fibers on bx

mitochondrial encephalomyopathy
heteroplasmy

72

pt presenting with squamous cell lung cancer and hypercalcemia but no focal lytic bone lesions

humoral hypercalcemua of malignancy
caused by over secretion of parathyroid hormone related protein (causes increased resorption of bone but no increase in renal excretion)

73

mechanism of Clostridium perfingens toxin

gas gangrene
toxin = lecithinase, AKA phospholipase C. splits phospholipid molecules

74

40ish woman with multimonth history of fatigue and widespread MSK pain and decreased attention. soft tissue tenderness at multiple locations bilaterally

fibromyalgia
chronic pain and fatigue for 3+ months in the absence of other syndromes/causes
tx - incremental aerobic exercise

75

50+ hear old woman with pain and stiffness in shoulders and hips, weight loss. fever, malaise

polymyalgia rheumatica

76

which muscle plays the largest role in the valsava maneuver?

rectus abdominus muscles

77

which circuit provides a negative feedback system to regulate and maintain muscle tension?

golgi tendon organs
can inhibit contraction of a muscle that is exerting too much force (ie weightlifting) to avoid damage

78

which feedback system monitors muscle length and prevents over stretching?

muscle spindle system

79

mechanism of action for first line treatment in an acute gout attack?

colchicine
inhibits tubulin polymerization and disrupts PMN chemotaxis and phago
side effects =nausea, abdominal pain, diarrhea

80

What two factors determine bone mass?

Peak bone mass (largely genetic)
Rate of bone loss

81

Infant presenting with floppiness (hypotonia) and poor feeding. Stools are every other day and pellet-like. On PE large anterior fontanelle, large tongue, reducible umbilical hernia, low muscle tone.

Congenital Hypothyroidism
Caused by throid dysgenesis and iodine deficiency (european family). No symptoms initially since maternal T4 crosses placenta
T4 is involved in mylination in early life and infant is at risk of irreversible intellectual disability
Tx with levothyroxin in first 2 weeks of life to protect brain function

82

Pt with progressive weakness and difficulty combing his hair. No history of injuries. Bx shows MHC I overexpression on the sarcolemma with CD8+ lymphocyte infiltration

Polymyositis
Note: no heliotrope rash (dermatomyositis)

83

Kid with recurrent skin and mucosal infections, no pus, poor wound healing.

Leukocyte adhesion deficiency
Can have delayed cord seperation at birth
At risk for peripheral leukocytosis with neutrophilia

84

Leukocyte adhesion deficiency is characterized by the absence of?

CD18 - necessary for integrin formation which is essential for adhesion

85

Pt with a thoracic compression fracture

Osteoperosis

86

Initiating allopurinol treatment increases activity of which medication?

Azathioprine
Inhibition of XO results in increased conversion of azatioprine to 6-thioguanine which incorporates into DNA and suppresses bone marrow leukocyte production.

87

A humoral fracture puts which vessel at risk?

Deep brachial a.

88

Staph aureus has the virulence factor Protein A. What does it do?

Part of the outter PPG layer
Protein A binds the Fc portion of IgG Abs at the complement binding site to prevent complement activation. Causes decreased C3b production and impaired opsonization and phagocytosis

89

In a patient with giant cell arteritis, what is the most important mediator of this dz?

Interleukin-6
Tocilizumab is an mAb against IL6 and is effective in treating GCA

90

On PE of an injured knee, there is widening of the medial joint line when valgum force is applied on the lateral knee with the lower leg fixed. What is injured?

Medial collateral ligament
Attaches medial epicondyle of femus
Typically occurs after a twisting injury

91

A pt periodically has involuntary deviation of the head to the right with shoulder/neck pain lasting 30-40 minutes. It can be suppressed by placing a hand on the chin. This is?

Dystonia (spasmodic toricollis is cervical dystonia)
Sustained, involuntary muscle contraction

92

What is blepharospasm?

A focal dystonia involving involuntary forceful closure of the eyelids.

93

Sudden, brief, severe muscle contraction

myoclonus

94

Intermittent resistance in extension/flexion of a limb

Cogwheel rigidity
Parkinsons

95

Slow movement

Bradykinesia
Parkinson

96

Involuntary muscle activity that flows from on muscle group to another. Can be fragmented or jerky

Chorea
Huntington

97

Flinging of the limbs on one side of the body

Hemiballism
Contralateral injury to the subthalamic nucleus

98

child fell on outstretched hand and now holds his right arm at this side with elbow extended and forearm pronated. He injured the?

Annular ligamnet displacement
Radial head subluxation (nursemaid elbow)
Generally only occurs in kids under the age of 5

99

Multinucleated cell in Paget dz

osteoclast
Accumulation of monocytes

100

2 factors imporant in osteoclast differentiation

Macrophage colony-stimulating factor (M-CSF)
Receptor for activated nuclear factor kappa-B ligand (RANK-L)

101

What is the physiologic decoy receptor that decreases binding of RANKL to RANK?

osteoprotegrin (OPG)
This reduces differentiation and survival of osteoclasts
Loss of function mutation = juvenile Paget's dz

102

Late onset asthma, rhinosinusitis, eosinophilia that potentially has kidney, GI, or CV sysmptoms. Can have carpal tunnel like symptoms

Eosinophilic granulomatososis with polyangiitis (Churg-Strauss)
Mononeuritis multiples = vasculitis affecting epineural vessels (carpal tunnel symptoms)
Lab finding = Ab against PMN myeloperoxidase and perinuclear p-ANCA

103

Asymptomatic chronic smoker with digital clubbing, thickening of distal phalanges. Fingers have drumstick appearance, flat nail folds, and shiny distal fingers. Spongy nail beds. Causes?

Lung dz - TB, CF, bronchiectasis, pulm HTN etc
Heart dz - Cyanotic congenital heart dz, bacterial endocarditis
IBD
hyperthyroidism
malabsorption

104

First line therapy for a newly diagnosed RA pt?

Prednisone
Inhibits phospholipase A2
Methotrexate, sulfasalazine require weeks before providing symptom relief

105

Pt with acute knee pain with 3 similar episodes that resolved with OTCH analgesic. History of polycythemia and non compliant with phlebotomy. What is found on needle aspiration?

Needle shaped, negatively birefringent crystals
Myeloproliferative disorders increase urate production

106

Can osteoarthritis pts have morning stiffness?

Yes but brief

107

Pt has a puncture injury on right leg. Right foot is dorsiflexed and everted. Cannot stand on toes. Knee and hip muscle strength are intact. Pedal and tibial pulses are +2 and symmetric. XR negative for fracture. Pt will have sensory loss where?

Tibial n. injury at the popliteal fossa, causes foot plantarflexion
Plantar foot

108

In a clavicle fracture, what muscle will displace the medial fragment superiorly?

SCD m.

109

In a clavicle fracture, which muscle will displace the lateral fragment superiorly?

Trapezius m.

110

Pt with fever, flank pain, difficulty walking x 3 days. Pt lies supine with R knee flexed and externally rotated. Resists extension of the leg, thigh and hip

Psoas major abscess

111

Pt with Black stools, fever, weight loss, muscle pain. Smoker and IVDU. Muscle bx shows transmural inflammation of the mid-sized arteries with areas of homogenous, eosinophilic arterial wall necrosis. Areas of internal lamina disruption

Polyarteritis nodosa secondary to Hep B

112

Pt with claudication, ulceration, and gangrene. Bx shows inflammatory thrombosis and ischemia involving small and medium arteries of the extrremities

Thromboangiitis obliterans (Buerger dz) secondary to smoking

113

In acute gout, and medication is given that selectively binds IL1

Celecoxib
IL1 is only expressed in sites of inflammation

114

A pt was given a muscle relaxant prior to intubation. He develops vfib and his potassium climbs to 19. Which agent caused this?

Succinylcholine
Depolarizing neuromusclular blocking agent that is not broken down by AChesterase
Does cause significant K+ release and arrhythmias

115

A pt with a laceration is presenting 3 weeks later with high levels of actin-containing fibroblasts and increased metalloproteinase activity

Contracture - when excessive MMP activity causes excessive wound contraction (deformities)
MMPs degrade collagen and ECM proteins. Important in would healing

116

If giant cell arthritis is suspected, what should be ordered before performing a biopsy?

CRP or ESR
Sensitive but not specific
bx = specific

117

A kid with a recent illness is now limping and refusing to put weight on his leg. Likely has osteomyolitis. Where is the infection?

Long bone metaphysis - slow flow makes the microbe happy
Adults are less likely to develop hematogenous osteomyelitis due to closure of the epiphysial plate

118

A pt has difficulty climbing stairs and getting up from a chair, diplopia, dry mouth. Previous SHx of nailing his right tibia. 45 ppd smoking history, Erectile dysfunction. Decreased DTR's, CXR shows irregular round mass in the Right upper lobe

Lambert-Eaton myasthenic syndrome
Proximal muscle weakness, cranial n. involvement, autonomic syx (dry mouth, ED)
Approx half of LEMS pts have an associated malignancy (usually small cell lung cancer)
NOTE: LEMs have hyporeflexia, autonomic syx, and respond to repeat stimulation but MG does not

119

Scaphoid fx are at risk for which two complications?

Avascular necrosis
Nonunion

120

Post oophrectomy research animals have overexpression of RANK on the surface of bone cells. What is the effect of this?

Increased bone resorption
RANK-L is not able to interact with rank with RANK when osteoprotegrin is present because it is a decoy receptor. When OPG binds RANK-L it reduces the survival of osteoclasts
Bone turnover is regulated by OPG:RANK-L
High RANK-L - resorption, high osteoclast activity
High OPG - high formation, osteoblasts

121

A resting membrane potential is -70mV, which ion will flow out of the cell?

Potassium (-90)
Cl is also an anion but it has a low intracellular concentration

122

Follow a patellar fx, a pt has parathesia and numbness at the dorsum of the right foot and weak dorsiflexion. Where is the nerve compression?

Fibular neck
Common peroneal n.
Causes weak dorsiflexion and impaired senstation over the dorsal foot and lateral shin

123

Aside from elevated auto Ab what other lab abnormalities will SLE pts have?

decreased C3 and C4

124

Anti mitochondrial ab are found in pts with?

Primary biliary cirrhosis. Presents with pruritus, jaundice, malabsorption

125

A pt presenting with fatigue, dyspnea, and noncaseating granulomas most likely will have elevated calcium due to?

Activated Macrophages produce 1-a-hydroxylase which activates PTH-independent production of 1,25-dihydroxyvitamin D. This causes increased intestinal reabsorption of calcium
Sarcoidosis pt

126

A pt with RA is likely to see the dz spread to?

The cervical spine (sublaxtion, cord compression)

127

A pt is presenting with M. leprae (skin discoloration, epistaxis, loss of eyebrows/eyelashes). What should be given to alleviate his symptoms

Interferon gamma
M. leprae is controlled by Th1. Th1 secretes IFN gamma which activates macrophages. So, supplementing some IFN gamma helps the pt get ahead of the curve.

128

A neonate presents with FTT, lethargy, increased head circumference, hepatosplenomegaly, anemia, leukopenia. Bone marrow space revels infiltration of the medullary canal with primary bony spongiose tissue. Dx and pathology

Osteopetrosis
Malfunction of osteoclasts - failure of resorption and remodeling of bone. pts compensate with extramedullary hematopoiesis (large head, hepatosplenomegaly)

129

High alk phos, high calcium, low phos. Multiple fx in a low speed MVA

Osteitis fibrosa cystica
Consequence of untreated hyperPTH leading to over active osteoclasts.
Lesions on XR

130

An older adult with elevated elk phos should be evaluated for?

Suggestive of metastatic dz
lytic lesions = multiple myeloma, thyroid, kidney
Sclerotic lesions = prostate
Mixed lesions = breast and lung

131

Abx prescribed for acne that increases photosensitivity

Tetracyclines
Bind 30S

132

The palatoglossus m. is inn by the?

Recurrent laryngeal n.
Compression of this n. = hoarseness (Ortner syndrome)

133

Cellular structure at the dermal epidermal junction?

Hemidesmosome
Targer in bullous phemgoid

134

A pt has a non erythematous peraly dome shaped papule that is not pruritic

Molluscum contagiosum
Poxvirus
Spontaneous resolution after a few months

135

After lifting a heavy object a pt has weakness when medially rotating his arm. Which muscle is injured?

Subscapularis m.
medial rotation and adduction

136

What is Behcet dz?

Autoimmune vasculitis characterized by oral and genital aphthous uclers
HLA - B51

137

HLA B27 is associated with

Psoriasis
Ankylosing spondylitis
IBD (UC and Chron's)
Reactive arthritis

138

Pt presents with multiple fx after falling downstairs. On Xray, some of the fx are new and some are old. Labs: low vit D and phos, low-to-nL Ca2+, high alk phos. Dx?

Osteomalacia
Areas of unmineralized osteoid adjacent to normal trabeculae
Caused by vit D deficiency (with secondary low phos) due to malnourishment

139

The only rotator cuff muscle that can medially rotate the arm?

Subscapularis m.

140

An immigrant presents with multiple numb cutaneous and erythematous skin plaques and nodules, especially over the extremities and butt. Recent loss of eyebrows and eyelashes and several episodes of epistaxis. PMH includes childhood asthma and atopy. Which cytokine would improve his condition?

IFN gamma
Pt has Mycobacterium leprae. It is controlled by Th1 cells which secrete IFN gamma.
Severe lepromatous dz occurs with CD4+ cells differentiate into Th2 instead of Th1. Giving IFN gamma would activate the macrophages which recruite Th1 to the sites of infection.
IL-10 would be a terrible idea because it would further down regulate the Th1 immune response

141

After falling off of his horse a pt is unable to raise his left arm and lets it hang by his side pronated. Which nerves and muscles are involved?

Erb palsy, waiter's tip
Upper trunk of brachial plexus(C5-C6)
affects the deltoid, supraspinatus, infraspinatus, and biceps

142

Inheritance pattern for Duchenne Muscular Dystrophy?

X - linked, Xp21 - dystrophin which is a myocyte anchoring protein
By age 5 - delayed walking, clumsy, weak, enlarged calf muscles (pseudohypertrophy)
Elevated creatine kinase

143

If PIP and DIP are involved think?

OA
If just PIP and metacarpal think RA

144

What step in muscle excitation is unique to smooth muscle?

Phosphorylation of myosin
AP depolarizes myocyte mumbrane -> opens VGCC -> Ca 2+ binds and activates calmodulin -> activates myosin light-chain kinase -> phosphorylates myosin allowing for cross bridging (NOTE - phosphorylates for contraction, not relaxation)

145

Steps in contraction of skeletal m.

AP terminates on muscle fibers and release ACh -> binds sarcolemma -> signal moves to T-tubules -> Ca2+ release from sarcoplasm reticulum via ryanodine receptors -> Ca2+ binds troponin C -> conformation change in tropomysin allows actin to interact with myosin (note in Smooth m. actin phosphorylates myosin but does NOT bind) -> crossbridge = contraction

146

Which muscle pulls the testicles into the abdominal cavity to maintain temperature?

Cremaster m.
Derived from Internal oblique m.

147

RA is associated with which HLA?

HLA-DR4
Also DM

148

HLA-DR3 is associated with?

Chronic acitve hepatitis
Sjogren syndrome
T1DM

149

Spinal stenosis is caused by thickening of which ligament?

Ligamentum flavum
Common in lumbar regions and presents with posture dependent lower extremity pain, numbness/parethesia, and weakness.
Most common cause is degenerative arthritis of the spine which results in narrowing of the spinal canal due to intervetebral disc herniation, ligamentum flavum hypertrophy, and osteophyte formation affecting the facet joints

150

What type of inhibitor allows the enzyme to reach the same Vmax but additional substrate is required to reach the max velocity (increases Km).

Competitive inhibitor

151

What would be a good tx for a 40ish female pt with a vertebral fx and fam hx of breast cancer?

Raloxifene - SERM. Estrogen agonist in bone to prevent osteoporosis but antagonist in breast tissue
Tamoxifen would not be a good fit because although it is an antagonist in breast tissue and an agonist on bone (to reduce Osteoperosis) it is also an agonist on the uterus and limits its osteoperosis efficacy

152

Embryonic origin of the thymus and inferior parathyroids?

3rd pouch
Superior parathyroids (4th)

153

What type of junctions are found between osteocytes?

Gap junctions
Long intracanalicular processes that extend through the bone matrix.
Allow for transmission of signals and nutrient exchange
Help regulate bone remodeling by communicating with surface osteoblasts

154

Ab against snRNPs?

Anti-Smith
Specific for SLE

155

Pt with lung cancer plus proximal muscle weakness (difficulty getting out of a chair) and diplopia?

Lambert-Eaton syndrome
Usually small cell lung cancer

156

A pt on TB regimen presents with Anti-histone Ab and ANA. Dx?

Drug induced SLE
Linked to drugs that are metabolized by N-acetylation in the liver (procainamide, hydralazine, isoniazid)
Slow acetylators are at greater risk of drug induced SLE

157

A myasthinia pt is started on tx and presents with abd cramping, nausea, sweating diarrhea. Tx?

Scopalamine
Tx - MG with a cholinesterase inhibitor (pyridostimine) and has excessive muscarinic GI syx due to excessive cholinergic stimulation
Scopalamine is a selective muscarinic ACh receptor antagonist

158

Tx for Lyme dz?

Doxycline
Penicillin type abx (ceftriaxone)
Early lyme - rash
Early disseminated - facial palsy, AV node block
Late lyme - asymmetric arthritis, encephalopathy

159

adult Sickle cell Pt presents with hip and pelvic pain due to?

Avascular necrosis
Pain + restricted movement

160

Decreased levels of complement C3 and C4

SLE
ANA, anti-dsDNA, Anti-Smith

161

Gottron papules, heliotrope rash, muscle weakness

Dermatomyositis
Gottron papules = red or violaceous, flat-topped papules over joints and bony prominences
ANA, anti-Jo1
perimysial inflammatory infiltrate
Can be part of a paraneoplastic syndrome

162

Infant with constipation, lethargy, hypotonia, macroglossia, umbilical hernia, large anterior fontanelle?

hypothyroidism
Start on levothyroxine by 2 weeks
Protected in utero due to maternal T4

163

Man presents with pain in multiple joints. Blue-black spots on sclerae and darkening of the auricular helices. Dx?

Alkaptonuria
Deficiency in Homogentisic acid dioxygenase deficiency
ar, defect in tyrosine metabolism
Black deposits due to excess homogentisic acid

164

Anti-Jo 1 is directed against?

anti-histidyl-tRNA synthetase
Polymyositis - endomysial mononuclear inflammatory infiltrate and patchy necrosis of muscle fibers

165

What do all seronegative spondylarthropathies have in common?

HLA-B27
Human Leukocyte antigen class I serotype

166

Calcium pyrophosphate deposition in the synovial fluid is diagnositc of?

Pseudogout
Positively birefringent under polarized light (blue)

167

Which HTN med can increase Ca2+ reabsorption and be protective in osteoperosis?

Thiazides
Recommended for HTN tx in pts at risk of osteoperosis
Loops diurectics shed calcium

168

In paget's dz of the bone, the initial phase is dominated by which cell type?

Osteoclasts - increased activity
Bone pain + elevated alk phos in an elderly pt = Paget dz of the bone
Bx of mosaic pattern of lamellar bone is diagnostic

169

Phases of pagets dz of the bone?

osteolytic
Mixed
Osteosclerotic

170

Muscle bx that is myoglobin-rich, glycogen poor with many mitochondria is characteristic of?

Postural skeletal muscles (soleus, paraspinal)
Type I slow twitch
ATP from aerobic metabolism

171

Pt is put on a muscle relaxant and repeat muscle stimulation is decreased but equal initially but 30 min later a similar pattern to what would be seen in myasthenia gravis. What is the drug?

Succinylcholine
Fast acting depolarizing agent. Short administration (phase I blockade) has equal reduction but prolonged administration causes non depolarizing block (think MG pattern)

172

12 y/o girl has arthralgias and a + ASO titer. What is she at risk of developing?

Pancarditis (primary cause of morbidity in acute rheumatic fever)

173

Pathologic process of giant cell arteritis?

Granulomatous inflammation of the media
Usually involves branches of the carotid (esp temporal)
Tx - glucocorticoids