AAW - Skin/MS Flashcards

1
Q

supracondular fracture of the femur

what artery are you worried about

A

popliteal artery (runs behind the femur)

the superficial femoral artery becomes the popliteal after it runs through the adductor hiatus

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2
Q

CREST syndrome

and what autoantibody

A

Calcinosis, Raynaud phenomenon,
Esophageal dysmotility, Sclerodactyly, and
Telangiectasia.

a form of limited scleroderma

antiCentromere in Crest

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3
Q

pemphigus vulgaris mech of damage

characteristic “sign”

A

autoantibodies against desmoglein component of desmosome (macula adherens)

flaccid intraepidermal bullae caused by acantholysis (meaning the loss of intercellular connections) (keratinocytes in stratum spinosum are connected by desmosomes)

nikolsky sign - separation of epidermis upon manual stroking of skin

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4
Q

mech of bullous penphigoid

A

autoantibodies to hemidesmosomes (hemidesmosomes are down “bullow”)

spares the oral mucosa, and not as bad as pemphigus vulgaris

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5
Q

guyon canal syndrome

A

compression of the ulnar nerve at the wrist or hand, classically seen in cyclists due to pressure from handlebars

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6
Q

atrophy of intrinsic hand muscles, ischemia, pain, and edema due to vascular compression

what tumor may cause this

A

called thoracic outlet syndrome

caused by compression of lower trunk and subclavian artery

can be caused by pancoast tumor

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7
Q

you say “make a fist”

their 2nd and 3rd fingers stay straight

where is the lesion

you say “extend your fingers”

their 2nd and 3rd didgets stay flexed

where is the lesion

A

proximal median nerve - cannot flex

distal median nerve - cannot extend

same distal/medial dynamic goes for the ulnar nerve

Clawing is seen best with distal lesions because the remaining extrinsic flexors of the digits exaggerate the loss of the lumbricles - fingers are extended at the MCP, but flexed at the DIP and PIP joints

defects are less pronounced in proximal lesions; deficits present during voluntary flexion

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8
Q

injury to what nerve gives you foot drop

A

common peroneal

PED = Peroneal Everts and Dorsiflexes; if injured, foot dropPED

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9
Q

injury to what nerve presents with inability to invert and plantarflex the foot

A

tibial nerve

TIP = Tibial Inverts and Plantarflexes; if injured, can’t stand of TIPtoes

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10
Q

what molecule sits in the myosin binding groove on actin filaments and stops muscle contraction

what gets it out of the way

A

tropomyosin

Ca release binding to troponin C causes a conformation change that moves it out of the way

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11
Q

what bands in muscle shrink when contracted

A

H and I bands

(when you say HI to someone, you wave, which contracts your arm muscle)

A band is Always the same length

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12
Q

slow twitch muscle

A

1 slow red ox

type 1, red fibers are for slow, sustained contraction

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13
Q

denosumab

A

monoclonal antibody against RANKL

sometimes used to treat osteoporosis

think of a den full of bones

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14
Q

mutation that can be seen in osteopetrosis

A

carbonic anhydrase II

impaires ability of osteoclasts to generate acidic environment neccessary for bone resorption

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15
Q

patient has a lot of fractures, cranial nerve problems, pancytopenia

Dx?
Tx?

A

osteopetrosis

pancytopenia because bone fills marrow space

cranial nerve impingement and palsies as a result of narrowed foramina

Tx is bone marrow transplant (osteoclasts are derived form monocytes

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16
Q

patient says their hat size in increasing and they are having hearing loss, also have heart failure. serum Ca, phosphorus, and PTH are normal

disease?
histology?
serum finding?

A

paget disease (osteitis deformans)

localized disorder of bone remodeling caused by increase in both osteoblastic and osteoclastic activity

(hearilng loss from auditory foramen narrowing)

histo shows osteocytes within lacunae and chaotic, mosaic pattern of bone remodeling

get increased ALP

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17
Q

in osteitis fibrosa cystica, when do you get increased phophate? decreased phosphate?

A

increased - secondary hyperparathyroidism (e.g. ESRD where you cannot excrete PO4)

decreased - primary hyperparathyroidism

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18
Q

Li-fraumeni syndrome puts you at risk for what bone cancer

A

osteosarcoma

Li-fraumeni is a germline P53 mutation

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19
Q

genetics of Ewing sarcoma
patient age/sex
appearance of bone?
histo?

A

assc with 1(11;22) translocation

11+22 = 33 (patrick Ewing’s jersey number)

boys less than 15 years old (are what patrick ewing likes) (sorry patrick, this is my mneumonic)

onion skin appearance in bone (patrick ewing is as big as shrek, onions have layers thing was in shrek)

anaplastic small blue cells (the world is small and blue compared to a giant like patrick ewing)

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20
Q

expansile glistening mass within the medullary cavity

men 30-60 yo

what tumor

A

chondrosarcoma

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21
Q

soap bubble appearance of bone`

what condition

A

giant cell tumor

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22
Q

codman triangle on bone

A

indicative of osteosarcoma

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23
Q

vertebral fusion, stiff spine, uveitis, and aortic regurg

A

ankylosing spondylitis

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24
Q

adult male
dactylitis
asymmetric and patchy arthritis
they also have nail lesions and papules and plaques with silvery scaling on knees

A

psoriatic arthritis

HLA-B27

also see “pencil in a cup” on xray

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25
Q

someone had a GI illness then presents with

conjunctivitis
urethritis
arthritis

A

reactive arthritis (Reiter syndrome)

“can’t see, can’t pee, can’t bend my knee”

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26
Q

heart problems assc with lupus

kidney problems assc with lupus

A

libman-sacks endocarditis - wark like vegetations on both sides of valve. also you can find anticardiolipin antibodies (which can give a false positive on tests for syphilis)

lupus nephritis (type III hypersensitivity reaction) - either nephritis (diffuse proliferative glomerulonephritis) or nephrotic (membranous glomerulonephritis)

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27
Q

autoantibodies to postsynaptic ACh receptor = ?

antibodies to presynaptic Ca channels = ?

A

autoantibodies to postsynaptic ACh receptor = myasthenia gravis. give edrophonium to diagnose, get ptosis, diplopia, weakness that worsens with muscle use. assc with thymic hyperplasia

antibodies to presynaptic Ca channels = lambert-eaton myasthenic syndrome. Proximal muscle weakness, autonomic symptoms (dry mouth, impotence). improves with muscle use. (assc with small cell lung cancer)

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28
Q

widespread excessive fibrosis and collagen deposition throughout the body. sclerosis of skin, manifesting as puffy and taut skin.

rapid progression, early visceral involvement

what disease
what autoantibodies

A

diffuse scleroderma

anti-Scl-70 antibody (anti-DNA topoisomerase I antibody)

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29
Q

autoantibodies in CREST syndrome (limited scleroderma)

A

anti Centromere (C for CREST)

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30
Q

acantholysis

A

separation of epidermal cells

seen in pemphigus vulgaris

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31
Q

acanthosis

A

epidermal hyperplasia (increased spinosum)

seen in acanthosis nigricans

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32
Q

in what common skin condition to you see nuclei still in the stratum corneum

A

psoriasis

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33
Q

leser-trelat sign

A

sudden appearance of multiple seborrheic keratoses, indicating and underlying malignancy (GI, lymphoid)

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34
Q

celiac disease - what skin manifestiation

A

dermatitis herpetiformis

deposits of IgA at tips of dermal papillae, often found on elbows

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35
Q

things assc with acanthosis nigricans

A

hyperinsulinemia (diabetes, obesity, cushing)

visceral malignancy (gastric adenocarcinoma)

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36
Q

herald patch followed days later by “christmas tree” distribution

multiple plaques with collarette scale

what is it
tx?

A

pityriasis rosea

self resolving in 6-8 weeks

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37
Q

skin cancer that appears as a nonhealing ulcer or scaling plaque

what kind of cancer
nuclei?

A

basal cell

palisading nuclei

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38
Q

tumor marker for melanoma

mutation?

if they have the mutation, what drug can you give

A

s-100 (neural crest (mesodermal) origin) (neural crest keeps it 100)

also for neural tumors, schwannomas, langerhans cell histiocytosis.

BRAF kinase mutation (activating mutation) (zac braf has melanoma)

metastatic or unresectable melanoma in patients with BRAF V600E mutation may benefit from vemurafenib (melanomas look like a painting, or mural), a BRAF kinase inhibitor

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39
Q

LTB4

A

leukotriene B4

a neutrophil chemotactic agent. Neutrophils arrive B4 others

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40
Q

LTC4, D4, E4

do what

drugs that block them?

A

leukotrienes C4, D4, and E4

increase bronchial tone

zarfilukast, montelukast block the creation of them

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41
Q

PGI2

A

Prostaglandin I2

“Platelet-Gathering Inhibitor”

inhibits platelet aggregation and promotes vasodilation

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42
Q

allopurinol mech

drug interactions?

A

inhibits xanthine oxidase

increases concentrations of azathioprine and its toxic metabolite, 6-MP (normally metabolized by xanthine oxidase) - if you give both it can cause an aplastic anemia

43
Q

febuxostat

A

inhibits xanthine oxidase

44
Q

probenecid

A

inhibits reabsorption of uric acid in PCT (also inhibits secretion of penecillin)

used in gout

45
Q

etanercept

A

fusion protein (receptor for TNF-alpha and IgG Fc) produced by recombinant DNA

etanerCEPT is a TNF decoy reCEPTor

46
Q

infliximab

A

the DALI lama INFLIX pain on TNF-alpha

anti TNF-alpha monoclonal antibody

used in IBD, RA, ankylosing spondylitis, psoriasis

47
Q

adalimumab

A

the DALI lama INFLIX pain on TNF-alpha

anti TNF-alpha monoclonal antibody

used in IBD, RA, ankylosing spondylitis, psoriasis

48
Q

comon drug that causes gout

what do you see under a microscope of gout aspirate

A

thiazide diuretics

negatively birefringent crystals in joint aspirate*

49
Q

15 month old

multiple skin nodules
poor feeding
pallor to conjunctivae
multiple erythematous nodules on trunk
raised tender spots on head
oral ulcers

x-ray of head reveals circular lytic lesions

disease?
cells?
histo?

A

langerhans cell histiocytosis (histiocytosis X) - abnormal proliferation of langerhans cells, which are just are tissue-specific dendritic cells found only in the skin. they come from the bone marrow

dendritic cells, macorphages and b-lymphocytes make up the antigen-presenting cells (APCs), which are the only cells that express MHCII (which is used for CD4 t cell activation)

biopsy shows heterogenous mix of langerhans cells with eosinophils, neutrophils, histiocytes.

langerhans cells have tennis racket shaped vacuoles known as Birbeck granles

50
Q

only muscle that comes from the third branchial arch

A

stylopharyngeus

used to elevate the pharynx and larynx

51
Q

1st brancial arch derivatives

abnormalities?

A

chew (MMM)

maxillary process (maxilla, zygoMatic bone)

Mandibular process (Meckel cartilage, Mandible)

Malleus and incus, sphenoMandibular

Masseter, lateral and Medial pterygoids, Mylohyoid

pierre robin sequence is malformation of 1st and 2nd brancial arches - micrognathia, glossoptosis, cleft palate, airway obstruction

treacher collins syndrome - neural crest dysfunction –> mandibular hypoplasia, facial abnormalities

52
Q

second branchial arch derivatives

A

Smile

reichert cartilage: Stapes, Styloid process, Stylohyoid

muscles of facial expression, Stapedius, stylohyoid, platySma

53
Q

4th-6th branchial arch derivatives

A

ACCCT

arythenoids
cricoid
corniculate
cuneiform
thyroid

(used to sing and act)

4th: most pharyngeal constrictors; cricothyroid
6th: all intrinsic muscles of larynx except cricothyroid

54
Q

branchial arches mneumonic

A

when at the restaurant of the golden arches, children tend to first chew 1, then smile 2, then swallow stylishly 3, or simply swallow 4, then speak 6

55
Q

what makes up the spermatic cords:

internal spermatic fascia
cremasteric muscle and fascia
external spermatic fasci

A

ICE
tie

internal spermatic fascia - transversalis fascia

cremasteric muscle and fascia - internal oblique

external spermatic fascia - external oblique

56
Q

bugs that cause palm and sole rashes

A

your drive CARS using your palms and soles

Coxsackie A, Rickettsia, secondary Syphilis

57
Q

tick bite - rash starts centrally and spreads out, sparing palms and soles

what bug
what vecotr

A

typhus

endemic (fleas) - Rickettsia typhi

epidemic (human body louse) - Rickettsia prowazekii

58
Q

rash - monocytes with morulae (mulberry-like inclusion) in cytoplasm

rash - granulocytes with morulae (mulberry-like inclusions) in cytoplasm

A

MEGA berry - a mulberry is a huge berry

Monocytes = Ehrlichiosis
Granulocytes = Anaplasmosis
59
Q

farmer has pneumonia and then develops endocarditis

A

not related to skin ms, but talked about with the other tick-borne rashes…

Q fever - Coxiella burnetii - can come from aerosols of cattle/sheep amniotic fluid

closely related to rickettsia but it is Queer because it has no rash or vector and its causative organism can survive outside in its endospore form

60
Q

what arteries for anastomoses between the ulnar and radial arteries

A

the deep and superficial palmar arches

61
Q

drugs that can cause stevens-johnson syndrome

A

some epilepsy drugs - ethosuxamide, phenytoin, fosphenytoin, carbamazepine, lamotrigine, allopurinol, sulfa drugs, penicillin

Steven johnson has epileptic allergy to sulfa drugs, allopurinol and penicillin

62
Q

central american

multiple numb cutaneous erythematous skin plaques

lesions in extremities and buttocks

loss of eyebrows and lashes

epistaxis

what disease?
what cytokine can you give?

A

lepromatous leprosy

in lepromatous leprosy your Th cells are differentiated into Th2 instead of Th1. In individuals with Th1 responses, the macrophages respond to the interferon-gamma produced by the Th1 cells and you get “tuberculoid” leprosy.

can give interferon-gamma, which mimics the Th1 response

63
Q

7yo that is now having trouble keeping up with other kids at recess. has hypertrophied calfs. normal reflexes, but decreased stregth

what disease
what inheritance

A

duchenne muscular dystrophy (x-linked recessive)

64
Q

what is wrong in ehlers-danlos syndrome

differentiate between:

hypermobility type
classical type
vascular type

A

faulty collagen synthesis

hypermobility type - joint instability, most common

classical - joint and skin symptoms, mutation in type V collagen

(remember that type IV collagen defect is alport syndrome)

vascular - vascular and organ rupture, deficient type III collagen

65
Q

drugs that cause drug induced lupus

A

HIPPES have lupus

Hydralazine, INH, Procainamide, Phenytoin, Etanercept, Sulfa drugs

66
Q

14 yo

leg cramps after trying out for soccer

after tryouts, urine had reddish tinge

what disease
what is deficient

A

McArdle

glycogen phosphorylase in the muscle tissue, cannot cleave individual glucose-1-p molecules off of glycogen

67
Q

24yo

sensorineural hearing loss, heart block, cerebellar ataxia, easy fatigability, proximal muscle weakness

myopathy diagnosed in childhood

muscle biopsy shows some red stuff in some cells

A

ragged red fiber disease

rare

mitochondrial inheritance

68
Q

areas of unmineralized osteoid adjacent to normal trabeculae in a homeless man

disease?
labs?

A

osteomalacia

decreased vit d
decreased Ca
increased PTH
decreased phosphate

hyperactivity of osteoblasts leads to increased ALP

69
Q

Rb gene is what

at risk for what cancers if it is mutated

gene product does what

A

tumor suppressor gene

RetinoBlastoma, osteosarcoma

gene product inhibits E2F, blocks G1–> s phase

70
Q

tumor marker for hairy cell leukemia

Tx?

A

TRAP

Tartrate Resistant Acid Phosphate

The pure of heart, hairy man CLAD in armor is climbing the BINE stalk to TRAP the giant

causes marrow fibrosis - dry tap on aspiration

patients usually have massive splenomegaly

Tx - cladribine (purine analog, stops DNA synth) (a big, pure of heart hairy man clad in armor climbing the bine stalk), pentostatin

71
Q

tick bite

arkansas

small, dark lesion

fever, malaise

gram neg coccobacillus, mostly intracellular

A

francisella tularensis

ticks, rabbits, deer flies

72
Q

cellulitis and osteomyelitis from an animal bite

A

pasteurella multocida

73
Q

nerve that innervates the adductor pollicis

A

ulnar (!) - also innervates the interosseus

the ulnar is on the medial side of the hand, think of the man with his palms showing anteriorly

74
Q

genetic defect in achondroplasia

A

fibroblast growth factor receptor 3 gene

80% are spontaneous mutations, remaining cases are inherited in an autosomal dominant fasion

75
Q

which muscle lowers the jaw while yawning

A

lateral lowers
m’s munch

lateral pterygoid opens

masseter, teMporalis, medial pterygoid munch

76
Q

temporal arteritis is assc with what joint stuff

A

polymyalgia rheumatica

both are treated with low-dose corticosteroids

77
Q

oral/facial abscess that drains through sinus tracts, forms yellow “sulfur granules;” can cause pelvic inflammatory disease with IUDs

causative agent?
Tx?

A

actinomyces

as with other gram positive bacterial with long, branching filaments resembling fungi, treatment is to SNAP the branches:

Sulfonamides for Norcardia

For Actinomyces, use Penicillin

78
Q

drug used to treat osteoporosis that can cause stomach pain and hematemesis

A

-dronates

bisphosphonates

take them with a glass of water and remain upright for 30 min

79
Q

what antibodies react to the cardiolipin antigen used in syphilis serology

what disease is it associated with

A

antiphospholipid antibodies

in lupus - also see anti-smith and ani-dsDNA

80
Q

someone comes in with shoulder weakness and has anti-SRP antibodies

what is causing the damage

what disease

A

endomysial inflammation with CD8+ T cells (lymphocytes)

polymyositis - most often involves the shoulders

if there was a rash, dermatomyositis is on the DDx

81
Q

what intrinsic muscle of the larynx is not innervated by the recurrent laryngeal nerve

A

the cricothyroid (derives from the fourth branchial arch)

whereas all of the others are derived from the 6th branchial arch

82
Q

what is one rare kidney SE of a statin

A

rhabdomyolysis, leading to acute tubular necrosis

83
Q

what things can cause malignant hyperthermia

A

succinylcholine and the inhaled anesthetics (-fluranes)

84
Q

guy returns from vacation down south

exquisitely tender and enlarged lymph nodes. fever, chills, general weakness

painful ulcer with dark hemorrhagic purpura on the arm where a flea bit him

gets abnormal coagulation times

what organism

A

yersinia pestis (!)

85
Q

achilles tendinitis

what antibiotic

A

fluoroquinolones (-floxacins)

86
Q

umbilicated papules on the skin

what is it

A

molluscum contagiosum (poxvirus)

87
Q

winged scapula

what is damaged - nerve, muscle, and spinal origin

occasional complication of what surgury

A

long thoracic nerve - branch of C5,6,7

innervates serratus anterior muscle

mastectomy

88
Q

labs in paget disease

4 phases

A

increased ALP

normal phosphate and Ca

phases:

  1. osteoclastic
  2. mixed
  3. osteoblastic
  4. quiescent state - clastic and blastic activity is minimal
89
Q

lesions in what area of the brachial plexus classically give you wrist drop and shoulder abduction

A

posterior cord - wrist drop is from radial nerve, shoulder abduction is from axillary nerve

90
Q

rash starts in face and neck, moves to trunk and extremities

tounge initially had white coating but is now red.

red oropharynx

pale area around the mouth

what causes this

A

strep pyo exotoxin

this is scarlet fever

91
Q

young patient uses his upper extremities to help himself get up

what type of mutation

A

frame-shift - x-linked recessive

this is the gower maneuver in deuschennes

92
Q

difference between becker and duchenne

A

becker is a non-frameshift insertion in dystrophin gene.

onset is later and less severe

but they are both still x-linked recessive

93
Q

looks like TB in an immunocompromised patient, but there is a negative PPD

what is it
what do you give to treat

A

Norcardia
aerobe
weakly acid fast
branching fillaments

SNAP the branches: sulfonamides for norcardia, actinomyces? use penicillin

94
Q

type of bacteria that borrelia burgdorferi is

A

a corkscrew-shaped spirochete

95
Q

good initial screening test for SLE because it is very sensitive

test to tell the prognosis of SLE

A

antinuclear antibody

it is not as specific as anti-dsDNA (bad prognosis) or anti smith

96
Q

patient has a compression of the left recurrent laryngeal nerve

what muscle of the mouth is also innervated by the nerve that the recurrent laryngeal branches off ot?

A

the palatoglossus

vagus

97
Q

muscle innervated by the glossopharyngeal

A

stylopharyngeus

98
Q

someone is given an antibiotic for acne vulgaris

they they sunburn really bad

what is it/what is it’s mech of action

A

tetracycline

binds 30s ribosomal subunit

can also be used to treat rickettsial infections, cholera, lyme disease, and chlamydia and mycoplasma pneumoniae

99
Q

patient has bad ring worm

what drug do you give

mech

SE - and why does it cause them (think endo hormones)

A

for bad tinea corporis, give ketoconazole

blocks formation of fungal membrane steroids

inhibits the enzymes desmolase, cyp 450, 17-alpha hydroxylase

inhibition of 17 alpha hydroxylase contributes to antiandrogenic effects like decreased libido, impotence, and gynecomastia

inhibition of desmolase results in skin darkening (desmolase is necessary for adrenal production of testosterone and cortisol)

with decrease cortisol, there is no feedback inhibition of the POMC, so you get addison like symptoms (hyperpigmentation)

100
Q

ankle ligament that always tears first

A

ATF = always tears first = anterior talofibular

101
Q

throwback: mech of sirolimus/rapamycin

A

for some reason, sirolimus sounded like a mountain of retreat to someone I know.

mTOR inhibitor, binds FKBP just like tacrolimus though

prevents response to IL-2

you can’t respond if you are on a mountain of retreat, also you don’t have to worry about you kidneys, but you might get panSIRtopenic

102
Q

smooth and skeletal muscle:

which pathway uses troponin C?

which uses calmodulin?

which phosphorylates myosin?

A

muscle: troponin C, which alters the conformation of tropomyosin, allowing actin to bind directly to myosin

smooth muscle: calmodulin, which activates myosin light chain kinase, phosphorylating myosin directly, allowing it to for a cross bridge with actin

103
Q

patient known to have an autoimmune disease undergoes a muscle stimulation test. the patient is initially unresponsive to the test, but after repetitive stimulation his muscle responds

A

lambert-eaton disease, antibodies against presynaptic voltage gated calcium channels