First Aid Respiratory/ MSK Flashcards
Emphysema
(a) Pathology
(b) Physical exam finding
(c) CXR finding
Emphysema = obstructive pulmonary disease (causes air trapping)
(a) Air space enlargement, reduced recoil and diffusion capacity, increased compliance
Increased elastase activity => loss of elastase fibers => increased compliance
(b) Pursed lip breathing = self PEEP
Exhaling thru pursed lips increases airway pressure
(c) CXR: barrel chest (increased AP diameter 2/2 air trapping)
Name the term that describes max volume that can be expired after a max inspiration
Vital capacity
2 things diphenhydramine is indicated for besides allergy
Motion sickness, sleep aid
2 histologic features of thyroid papillary carcinoma
- Orphan annie cells = empty-appearing nuclei
- psamomma bodies
- also seen in meningiomas and ovarian cystadenoma
Which lung cancer is associated w/
(a) Small dark blue cells
(b) Keratin pears
(c) Nests of neuroendocrine cells
(d) Glandular pattern on histology
Lung cancers: small cell and non-small cell (adenocarcinoma, squamous cell, large cell, bronchial carcinoid)
(a) Small dark blue cells = small cell (neoplasm of neuroendocrine cells)
(b) Keratin pearls seen in squamous cell carcinoma (central, RF: smoking)
(c) Nests of neuroendocrine cells = bronchial carcinoid tumor
(d) Glandular pattern = adenocarcinoma
What is pulmonary compliance?
(a) Example of disease that reduces pulm compliance
Pulmonary compliance = amount of volume change per unit of pressure
-so high compliance means it takes a lot of volume w/ a little pressure
(a) Decrease in pulmonary compliance w/ pulmonary fibrosis or pulmonary edema (decreases efficacy of diffusion surface)
Pathology of bronchiectasis (2 mechanisms)
(a) Associated conditions/RFs
(b) Clinical symptoms
Bronchiectasis = chronic inflammation and inability to clear mucoid secretions
(a) CF, primary ciliary immotility (Kartageners), smoking
(b) Productive cough, recurrent infections, hemoptysis
Differentiate Bohr and Haldane effect of H+ on Hb
Bohr effect in tissues where high H+ promotes O2 unloading
Haldane effect in the lungs where high O2 promotes H+ dissociation and CO2 formation
Tumor marker for medullary thyroid cancer
Calcitonin
-medullary thyroid cancer = of parafollicular (C-cells)
Compare the prognosis of lung cancers:
- large cell
- bronchial carcinoid
Bronchial carcinoid has excellent prognosis, while large cell carcinoma has a poor prognosis (less responsive to chemotherapy)
Obstructive vs. restrictive pulmonary disease
(a) Lung volumes
(b) FEV1/FVC ratio
Obstructive
(a) Air trapping => increased volumes
(b) Pathognomonic reduces ratio (under 80%) b/c both are reduced by FEV1 is more significantly reduced
Restrictive
(a) Decreased volumes, expansion is restricted
(b) Ratio is normal, at or over 80%
MC cause of fat emboli
Long bone fracture
Typical presentation: pt fractures femur then becomes suddenly SOB w/ CP
Two places pain from the diphragm radiates
Pain from diaphragmatic irritation (ex: air or blood in peritoneal cavity) can be referred to the shoulder (C5) and trapezius (C3,C4) b/c C3,4, and 5 keep you breathing and alive (phrenic nerve)
Give example of causes of hypoxemia with
(a) Normal A-a gradient
(b) Elevated A-a gradient
Normal Alveolar-arterial gradient = 10-15mmHg
(a) Hypoxemia w/ normal gradient: high altitude, hypoventilation (ex: opioid overdose causing respiratory depression)
(b) Hypoxia w/ elevated A-a gradient from V/Q mismatch or a limitation in diffusion (ex: fibrosis), or right to left shunt
ARDS
(a) CXR
(b) CT
(c) Histology findings
(d) How is severity graded?
ARDS
(a) B/l alveolar infiltrates
(b) CT: found glass opacities, dependent consolidations
(c) Histo: diffuse alveolar damage w/ exudate (protein-rich leakage) forming intra-alveolar hyaline membrane
(d) Severity graded on PaO2 / FiO2 ratio or by required PEEP
Tx of ARDS- 2 parts
ARDS Tx
- Tx underlying cause: pneumonia, sespis, acute pancreatitis, uremia
- Vent w/ high PEEP and low tidal volumes
- high PEEP to prevent airway collapse at end-expiration and to recruit collapsed alveoli
- LOOWWW tidal volumes
Give a brief overview of basic asthma tx
Acute rescue inhaler = beta-agonist (to cause bronchodilation) Albuterol
For persistent asthma- start w/ daily meds
- Low dose ICS (inhaled corticosteroid fluticasone, budesonide) or can use monteleukast (antileukotriene)
- add LABA (Salmeterol) or monteleukast
- oral steroids if acutely in need
MC cause of primary spontaneous pneumotohorax
Rupture of apical blebs or cysts, MC found in tall young thin males
Chronic bronchitis
(a) Clinical definition
(b) Pathology
(c) Physical exam findings
Chronic bronchitis = obstructive pulmonary disease
(a) Productive cough for 3+ mo of the year for 2 or more years (not necessarily consecutive)
(b) Hyperplasia of mucus secreting secreting glands in the bronchi
(c) Wheezing, crackles, cyanosis, CO2 retention (hypercapnia) => secondary polycythemia
Malignancy associated w/ asbestosis exposure
Mesothelioma
Complications of neonatal respiratory distress syndrome
(a) Heart
(b) Lungs
(c) If give supplemental O2
Complications
(a) Patent ductus arteriosus b/c not a big enough increase of O2 tension that usually occurs at birth to close the shunt
(b) Bronchopulmonary dysplasia
(c) Giving 100% O2 can cause free radical damage of eyes and lungs => blindness, pulmonary dysplasia
Sleep apnea
(a) Differentiate central vs. obstructive
(b) Presenting symptoms
(c) Lab abnormality
Sleep apnea = repeated breathing arrest for at least 10 seconds during sleep
(a) Central due to lack of respiratory effort from reduced CNS drive. Obstructive from physical obstruction of the airway
(b) Daytime sleepiness
(c) Polycythemia- chronic hypoxia stimulating EPO release
What are club/Clara cells?
Club/clara cells = bronchiolar exocrine cells
- secrete detoxifying substance
- act as stem cells to regenerate bronchiolar epithelium
Mechanism of pseudoephedrine and phenylephrine
(a) Indication
(b) Toxicity
Pseudoephedrine and phenylephrine are both alpha agonists (Sudafed)
(a) Used as nasal decongestants- wrk by reducing edema, nasal congestion
(b) Toxicity- HTN, anxiety for pseudoephedrine 2/2 CNS stimulation
2 complications of pancoast tumor
Pancoast tumor = carcinoma in the lung apex
- invasion of cervical sympathetic chain => Horner’s (ipsilateral ptosis, miosis, anihidrosis)
- SVC syndrome- medical emergency of blocked SVC drainage
Predictive factor for neonatal respiratory distress syndrome
L:S ratio in amniotic fluid under 1.5
-indicating not enough surfactant => fetal lungs have high surface tension causing alveolar collapse
(lecithin:spingomyelin ratio)
Which drug is especially good for aspirin-induced asthma
Monteleukast (antileukotriene)
Which cancers have Psammoma bodies
Psammoma: concentric, laminated, calcified spheres
High yield: PSaMMoma Papillary thyroid carcinoma Serous cystadenocarcinoma of the ovary Meningioma Mesothelioma (lung)
Which lung cancers are central
‘Sentral’: small cell, squamous cell
Squamous cell: hilar mass arising from the bronchus
What is Homan’s sign?
Physical exam finding of DVT
-calf pain upon dorsiflexion of the foot
Differentiate guaifenesin and dextromethorphan
Guaifenesin (Mucinex, Robittusin) is an expectorant- doesn’t suppress the cough reflex, just thins respiratory secretions
Dextromethorphan (Robittusin) is an antitussive (antagonist of NMDA glutamate receptors)
-abusive potential, mild opioid effect when used in excess
-Robittusin actually has both expectorant and antitussive
Describe the cell type lining the upper vs. lower respiratory tract
Pseudostratified ciliated columnar cells to the terminal bronchioles, then cuboidal cells in bronchioles
Next line of tx for allergic asthma resistant to inhaled steroids and LABA
Omalizumab = monoclonal anti-IgE antibody
-binds to unbound serum IgE
Ferrous vs. ferric
(a) Hgb form
Just the “2 of us” => ferrous = Fe2+
Ferric = Fe3+
(a) Hgb w/ Fe2+ has high affinity for O2, while methemoglobin is oxidized (Hb-Fe3+) and has lower affinity for O2
3 criteria of Light’s criteria for exudative pleural effusion
- Fluid:serum protein over 0.5
- Fluid:serum LDH over 0.6
- Fluid LDH over 2/3(ULN)
46 yo F admitted for severe pancreatis, w/in 24 hrs develops severe hypoxemia requiring vent support w/ high FiO2
- rhonci and crackles of exam
- ABG on 60% FiO2: pH 7.43, pCO2 35, PO2 108
Dx
Dx = ARDS (acute respiratory distress syndrome)
- acute inflammatory lung injury w/ increased vascular permeability of the lungs
- PaO2 / FiO2 ratio grades severity
- leakage of protein-rich (exudative) fluid causes noncardiogenic pulmonary edema
Differentiate diphenhydramine from loratadine
(a) Side effect
(b) Indication
Diphenhydramine (benadryl) is a first generation H1 histamine receptor blocker, toxicity includes sedation
-so is dimenhydrinate (dramamine)
Loratadine (Claritin) is a second generation w/ much less CNS entry (b/c lipophobic) => far less sedating
-so is fexofenadine (Allegra) and cetrizine (Zyrtec)
-allergy indicated for both, diphenhydramine also indicated for motion sickness and sleep aid
B/l hilar lymphadenopathy w/ noncaseating granulomas
Sarcoidosis = restrictive pulmonary lung disease
Utility of the alveolar gas equation
Use the alveolar gas equation to calculate partial pressure of oxygen in the alveoli, then can use this to calculate the A-a (Alveolar-arterial) gradient
Exposures to the following affect the upper or lower lobes?
(a) Asbestosis
(b) Coal
(c) Silica
(a) Asbestosis affects lower lobes
(b,c) Coal and silica
3 parts of Virchow’s triad
SHE
Stasis
Hypercoagulability
Endothelial damage (exposed collagen triggers the clotting cascade)
Thyroid cancer
(a) MC
(b) Not from follicular cells
(c) Worst prognosis
(d) Associated w/ Hashimoto’s
(e) MC benign thyroid neoplasm
Thyroid cancer
(a) 90% are papillary thyroid cancer, excellent prognosis => thyroidectomy
(b) Medullary thyroid cancer is from parafollicular (calcitonin, not PTH, secreting) cells
(c) Anaplastic/undifferentiated (only 1-2% of thyroid cancers) progress rapidly and have poor prognosis
(d) B-cell lymphoma associated w/ Hashimoto’s
(e) MC benign thyroid neoplasm = follicular adenoma
Which lung cancer cells may produce
(a) Carcinoid syndrome
(b) Cushings
(c) SIADH
(d) Hypercalcemia
(e) beta-hCG
(f) Lambert-Eaton
Lung cancer paraneoplastic syndromes
(a) Carcinoid syndrome (flushing, diarrhea, wheezing 2/2 5-HT secretion) by bronchial carcinoid tumor
(b) Cushings (2/2 ACTH secretion) by small cell
(c) SIADH by small cell
(d) Hypercalcemia 2/2 PTHrP secretion by squamous cell carcinoma
(e) beta-hCG can be secreted by large cell carcinoma
(f) Lambert-Eaton 2/2 antibodies against pre-synaptic Ca2+ channels 2/2 small cell carcinoma
Which 4 structures (and at what vertebral level) perforate the diaphragm?
“I ate 10 eggs at 12”
IVC T8, T10 esophagus, aorta T12
T8- vena cava (IVC)
T10- esophagus and vagus (CN X at T10)
T12- aorta
Why is SVC syndrome a medical emergency?
B/c it can raise intracranial pressure enough to cause aneurysm/rupture of intracranial arteries
Differentiate follicular adenoma and follicular carcinoma
Both follicular are from follicular cells (produce TSH), both are cold nodules
- adenoma has complete capsular confinement on histology
- while carcinoma has some invasion of the blood vessels or thyroid capsule on histology
Tx for DVT
(a) Acutely
(b) Chronic prevention
DVT mgmt
(a) Acutely- heparin or LMWH (enoxaparin)
(b) Chronically prevent w/ an oral anticoagulant: warfarin or Noac (Rivaroxaban)
What pH abnormality would you expect in response to high altitude?
At high altitude there’s lower PIO2 (partial pressure of inspired O2), so you increase ventilation to compensate which causes you to blow off more CO2 (decreased PCO2)
Decreased PCO2 = respiratory alkalosis
Physical exam finding besides for hypoxemia that can help distinguish fat embolism from pulmonary embolism
Fat embolism associated w/ petechial rash (and typically after long bone fracture)
Asthma
(a) Inspiratory to expiratory ratio
(b) Clinical test
(c) Pathology
Asthma: bronchial hyperresponsiveness causing reversible bronchoconstriction and smooth muscle hypertrophy
(a) Reduced insp/exp ratio (takes longer to expire)
(b) Methacholine (muscarinic receptor agonist) challenge
(c) Mucus plugs in sputum
Physiology of neonatal respiratory distress syndrome
(a) 2 causes besides prematurity
(b) CXR appearance
Neonatal respiratory distress syndrome = hyaline membrane disease- type II pneumocytes aren’t developed yet => surfactant deficiency => high alveolar surface tension/low compliance => alveolar collapse
(a) Prematurity MC, also maternal diabetes (high fetal insulin decreases surfactant production) and C-section (reduced fetal corticosteroid release)
(b) Ground glass opacities on CXR
Differentiate taut and relaxed form of Hgb
(a) Which is favored by H+
Taut form has lower affinity for O2 (form in tissues to facilitate O2 unloading) vs. relaxed form has higher affinity (300x) for O2 (as in lungs to facilitate O2 uptake)
(a) H+/acidosis favors O2 unloading, so favors taut form
Ex: exercising tissue produces lactic acid, Hb acts as buffer for H+ therefore unloading O2 into tissues
Differentiate minute ventilation and alveolar ventilation
Minute ventilation = amount of gas that enters lungs per minute
Alveolar ventilation = amount of gas that enters the alveoli per unit time
What drug is first line therapy for chronic asthma
(a) Mechanism
Inhaled corticosteroids = fluticasone, budesonide
a) Inhibits cytokine syntesis, inactivated NF-kappaB (TF that induces TNF-alpha
3 drugs for pulmonary hypertension- describe the classes
(a) Bosentan
(b) Sildenafil
(c) Iloprost
(a) Bosentan = endothelin receptor antagonist to decreased pulmonary vascular resistance
(b) Sildenafil = PDE-5 inhibitor to prolong vasodilatory effect of NO
(c) Iloprost = prostacyclin analogs w/ direct vasodilatory effects
Name a drug in addition to guaifenesin that acts as an expectorant
(a) Use in CF pts
N-acetylcysteine (yes the NAC that’s used in acetaminophen overdose) can be used as mucolytic
-cleaves disulfide bridges btwn mucus glycoproteins
(a) Loosens mucus plugs in CF pts
MC lung cancer in nonsmokers
Still adenocarcinoma (MC overall)
Obstructive vs. restrictive pulmonary disease
(a) Chronic bronchitis
(b) Idiopathic pulmonary fibrosis
(c) ARDS
(d) Myasthenia gravis
(e) Asthma
(f) Bronchiectasis
(g) Emphysema
(h) Sarcoidosis
Obstructive (obstructed flow) vs. restrictive (restricted expansion)
(a) Chronic bronchitis (hypertrophy of mucus secreting cells) is obstructive
(b) IPF is restrictive
(c) ARDS is restrictive
(d) MG is restrictive w/ normal Aa gradient (reduced muscle effort)
(e) Asthma is obstructive (airway hyperresponsiveness and mucus plugs)
(f) Bronchiectasis is obstructive
(g) Emphysema obstructive
(h) Sarcoidosis restrictive
Define physiologic dead space
(a) 2 components
Physiologic dead space = amount of air inhaled that does not participate in gas exchange
(a) Air in the upper airway (like throat and stuff) + alveolar dead space (due to V/Q mismatch) j
Transudative vs. exudative pleural effusion
(a) Protein content
(b) Mechanism
(c) Etiologies
Transudative
(a) low protein
(b) Due to increased hydrostatic or decreased oncotic pressure
(c) HF, nephrotic syndrome, hepatic cirrhosis
Exudative
(a) high protein
(b) state of increased vascular permeability
(c) Malignancy, pneumonia
Describe how exercise changes the V/Q matching throughout the lungs
Exercise causes the V/Q ratio from the apex to base to become more uniform
-w/ increased cardiac output there is vasodilation of the apical capillaries => V/Q ratio approaches 1
Cutoff for pulmonary hypertension
(a) Normal pulmonary artery pressure
(b) Mutation implicated in idiopathic/familial PAH
(b) Name 2 secondary etiologies
Pulm HTN defined as pulmonary artery pressure over 25 mmHg at rest (or over 30 during exercise)
(a) Normal: 10-14 mmHg
(b) BMPR2 gene mutation predisposing to abnormal vasculature b/c normally protein acts to inhibit smooth muscle growth => hyperplasia of smooth muscle
(c) Secondary causes of PAH: hypoxia 2/2 damage to lung parenchyma (ex: COPD), increased backflow pressure from left heart (left HF, severe MS)
- hypoxia => pulmonary vasoconstriction => PAH
What is methemoglobinemia?
(a) How does it classically present clinically?
(b) Tx
Methemoglobinemia = oxidized Hgb (Hb-Fe3+ instead of normal Hb-Fe2+) which has a lower affinity for O2, higher affinity for CN-
(a) Presents w/ cyanosis and ‘chocolate covered’ (deoxygenated) blood
(b) Tx w/ supplemental O2 and methylene blue
- methylene blue acts as electron acceptor to help recycle NADPH so NADP+ is more available to reduce Hb-Fe3+
At what part of the breath is the peripheral vascular resistance the lowest?
At functional reserve capacity (volume left after normal expiration) PVR is at a minimum, airway and alveolar pressure are 0
Differentiate ACL and PCL
Anterior and posterior here refer to their sites of tibial attachment
So PCL attaches the femur to posterior tibia
Which muscle abducts the arm
Arm abduction is initiated by supraspinatus (rotator cuff muscle) then taken over by deltoid
Muscle injured by pitching injury
Infraspinatous (I in SItS of rotator cuff muscles)
Nerve injured by
(a) Fracture of surgical neck of the humerus
(b) Midshaft fracture of the humerus
(c) Supracondylar fracture of the humerus
(d) Superficial laceration of the palm
Nerve injury
(a) Fracture of surgical neck of the humerus = axillary nerve (C5-C6)
(b) Midshaft fracture damages the radial nerve (C5-T1) in the radial groove
(c) Supracondylar fracture of the humerus => median nerve (C5-T1) injury
(d) Superficial laceration of the palm can damage the recurrent branch of the median nerve (C5-T1)
Waiter’s tip deformity vs. Claw hand
2/2 damage to upper trunk of brachial plexus (C5-C6 roots) => waiter’s tip deformity
Damage to lower trunk of brachial plexus (C8-T1) => clamp hand
Nerve injured by
(a) pelvic fracture
(b) fibular neck fracture
(c) Baker cyst
(d) Posterior hip dislocation
Nerve injury
(a) Pelvic fracture- femoral nerve (L2-L4) injury
(b) Fibular neck fracture can damage common peroneal nerve (L4-S2)
(c) Baker’s cyst in popliteal fossa can damage tibial nerve (L4-S3)
(d) Posterior hip dislocation can injury the inferior gluteal nerve (L5-S2)
What nerve innervates
(a) Gluteus maximus
(b) Gluteus medius
(c) Posterior thigh
(d) Perineum
Innervation of
(a) Gluteus maximus = inferior gluteal nerve (L5-S2)
(b) Gluteus medius and minimus by superior gluteal nerve (L4-S1)
(c) Posterior thigh by sciatic nerve (L4-S3) before it splits into common peroneal and tibial
(d) Perineum innervated by the pudendal nerve (S2-S4)
Landmark for nerve block during child birth
Can block the pudendal nerve (S2-S4), which innervates the perineum, using the ischial spine as a lnadmark
Distinguish nerves in charge of dorsi and plantar flexing the foot
PED TIP
Peroneal nerve Everts and Dorsiflexies (if injured, foot dropPED)
Tibial nerve Inverts and and Plantarflexes (if injured, can’t stand on TIPtoes)
In which direction to interveretebral discs most likely herniate?
Discs herniate posterolaterally b/c the posterior longitudinal ligament is much thinner than the anterior longitudinal ligament the lies along the midline of the vertebral bodies
Name the nerve and artery pairing that runs through the
(a) axilla
(b) surgical neck of the humerus
(c) Midshaft of the humerus
(a) Axilla: long thoracic nerve, lateral thoracic artery
(b) Surgical neck of the humerus: Axillary nerve, posterior circumflex artery
(c) Midshaft of the humerus: radial nerve (in the radial groove), deep brachial artery
Name the nerve and artery pairing that runs through the
(a) Cubital fossa
(b) Popliteal fossa
(c) Posterior to medial malleolus
(a) Cubital fossa: median nerve and brachial artery
(b) Popliteal fossa: tibial nerve and popliteal artery
(c) Posterior to the medial malleolus: tibial nerve and posterior tibial artery
Which type of muscle fibers are hypertrophied by weight training
Weight training causes hypertrophy of the fast-twitch, white (b/c less mitochondria and less myoglobin) muscle fibers
-fast-twitch fibers for fast but un-sustained contraction
Differentiate type 1 and type 2 muscle fibers
Type 1 = red fibers = slow twitch
- red b/c more mitochondria and more myoblin
- slower onset but sustained contraction
Type 2 = white fibers = fast twitch
- white b/c less mitochondria and less myoflobin
- faster reaction, but un-sustained
Mechanism by which osteoclasts dissolve bone
Osteoclasts secrete acid (via carbonic anhydrase II rxn which is deficient in osteopetrosis) and collagenases
Precursor cells of osteoblasts vs. osteoclasts
Osteoblasts (build bone) are from mesenchymal stem cells in the periosteum
-secrete collagen and catalyzing mineralization
Osteoclasts (break down bone) come from monocytes/macrophages, are multinucleated
Impact of estrogen on bones
Estrogen inhibits apoptosis of osteoblasts, and inhibits apoptosis in osteoclasts => helps maintain healthy strong bone
Explains why post-menopausal F (less estrogen) have higher risk of osteoporosis
Differentiate the mechanism by which bones of the skull/face and skeleton are formed
Endochondrial ossification of skeleton = first cartilage laid down, then replaced w/ woven bone and later remodeled into lamellar bone
Membranous ossification of skull and facial bones = woven bone formed w/o cartilage then later remodeled into lamellar bone
Explains why face/head is normal size in achondroplasia (defect in cartilage synthesis)
MC location of osteonecrosis
Osteonecrosis = avascular necrosis, MC site is the femoral head due to insufficiency of the medial circumflex femoral artery
What is osteitis fibrosa cystica?
Osteitis fibrosa cystica = ‘brown tumors’ of bone due to fibrous replacement of the bone
2/2 hyperparathyroidism
Infections associated w/ Reactive arthritis
Reactive arthritis (Reiter syndrome- ‘can’t see, can’t pee, can’t climb a tree’- uveitis, urethritis, arthritis
Post-GI (Shigella, Salmonella, Yersinia, Campylobacter) and chlamydia
MC lupus pt
Female of reproductive age and African descent
2 falsely abnormal lab values seen in antiphospholipid syndrome
Anticardiolipin antibodies and lupus anticoagulant can cause
- false positive VDRL
- prolonged PTT
Self-IgG in lupus that is
(a) Sensitive but not specific
(b) Specific but not sensitive
(c) Sensitive for drug induced lupus
(d) Prognostic indicator for renal disease involvement
Antibodies in SLE
(a) ANA
(b) Anti-dsDNA
(c) Antihistone
(d) Anti-dsDNA: poor prognostic indicator, MC seen w/ renal involvement
Describe lupus nephritis
(a) Nephritic
(b) Nephrotic
Lupus nephritis = type III hypersensitivity rxn (explains why C3 is low b/c immune complex deposition)
(a) Nephritic syndrome: diffuse proliferative glomerulonephritis
(b) Nephrotic: membranous glomerulonephritis
Elevated serum ACE levels, expect what histologic finding?
Elevated serum ACE is associated w/ sarcoidosis, in which case you’d see widespread noncaseating granulomas
Clinical findings of
(a) Polymyalgia rheumatica
(b) Fibromyalgia
Clinically
(a) Polymyalgia rheumatica- pain/stiffness in shoulders and hips (‘girdles’), can be w/ fever malaise and wt loss. No muscular weakness. F over 50
(b) Fibromyalgia- widespread MSK pain w/ stiffness paresthesias poor sleep and fatigue. F 20-50 yo
Tx
(a) Polymyalgia rheumatica
(b) Fibromyalgia
Tx
a) Polymyalgia rheumatica = low-dose corticosteroids
(b) Fibromyalgia = regular exercise, antidepressants (TCAs, SNRI
Pain/stiffness in pt w/ temporal arteritis
Polymyalgia rheumaticaaaaaa
-huge overlap in the two syndromes
Polymyositis vs. Dermatomyositis
(a) T cell involved
(b) Location of inflammation
Polymyositis (lacks cutaneous findings)
(a) CD8
(b) Endomysial inflammation (inner nerve sheath farther from skin)
Dermatomyositis (Gottron papules, heliotrope rash)
(a) CD4
(b) Perimysial inflammation (outer sheath, closer to skin)
What is myositis ossificans?
Metaplastic change of skeletal muscle into bone following muscular trauma
So get a ‘mass’ at the site of trauma, or found incidentally on radiography
Ab seen in
(a) diffuse scleroderma
(b) CREST syndrome
(a) Anti-Scl70 antibody = anti-DNA topoisomerase I Ab
(b) Anti-centromere Ab
Differentiate scale and crust
Scale (ex: eczema, psoriasis) is a flaking off of the stratum corneum
While crust is a dry exudate (ex: impetigo)
What is melasma?
Melasma = ‘pregnancy glow!’
Hyperpigmentation associated w/ pregnancy or OCP use
Etiology of vitiligo
Vitiligo = irregular areas of complete depigmentation 2/2 autoimmune destruction of melanocytes
Etiology of albinism
Albinism: normal amount of melanocytes, just reduced melanin production b/c of reduced tyrosinase activity or defective tyrosine transport
- also can be from failure of neural crest cell migration (b/c melanocytes are derived from neural crest cells)
- increased risk of skin cancer
Differentiate organisms implicated in cellulitis vs. abscess
Cellulitis = infxn is of the deeper dermis and subcutaneous tissue, from either S. pyogenes (GAS) or Staph aureus
While abscess is a walled-off collection of pus w/in deeper layers of skin that is almost always caused by S. aureus (often MRSA)
Differentiate mechanism of staph scalded skin syndrome and toxic epidermal necrolysis
SSSS: exotoxin destroys keratinocyte attachments in stratum granulosum only
vs. destruction of dermal-epidermal jxn seen in TEN
Molluscum contagiosum
(a) Clinical presentation
(b) Cause
Molluscum contagiosum
a) Small umbilicated papules (raised under 1cm
(b) Poxvirus
- seen in children or sexually transmitted in adults
Cause of necrotizing fasciitis
Bacterial infxns: anaerobes or S. pyogenes (GAS)
Results in crepitus from methane and CO2 production
Pemphigus vulgaris vs. bullous pemphigoid
(a) More severe
(b) Involves oral mucosa
(c) Consistency of bullae
Pemphigus vulgaris = IgG against desmogelin (component of desmosomes)
(a) Much more severe, potentially fatal
(b) Involves oral mucosa
(c) Flaccid bullae
Bullous pemphigoid (‘Abs bullo the epidermis’) = IgG against hemidesmosomes at BM
(a) Less severe
(b) Spares oral mucosa
(c) Tense bullae
Condition associated w/ Lichen planus
Lichen planus (pruritis, polygonal, purple) associated w/ HepC
Buzzwords for bone tumors
(a) Codman triangle
(b) Onion skin periosteal reaction
(c) Soap bubble appearance
(d) Sunburst pattern on Xray
(a) Codman triangle = osteosarcoma (of osteoblasts) from elevation of periosteum
(b) Onion skin periosteal rxn = Ewing sarcoma
(c) Soap bubble appearance = giant cell tumor (‘osteoclastoma’)
(d) Sunburst pattern = osteosarcoma (another description of Codman’s triangle)
Ewing sarcoma
(a) Demographic
(b) MC location
(c) Histology
(d) Xray
(e) Translocation
Ewing Sarcoma
(a) Boys under 15 yoa
(b) Diaphysis (shaft) of long bones
(c) Anaplastic small blue cells
(d) Onion skin periosteal rxn on Xray
(e) T(11;22) forming fusion protein
Skin cancer most likely to metastasize
(a) Tumor marker
Melanoma
(a) S-100 tumor marker
Describe Vemurafenib utility in metastatic or unresectable melanoma
Melanoma often driven by BRAF kinase, primary tx is excision w/ appropriately wide margins, but can also use Vemurafenib = BRAF kinase inhibitor
Especially useful in pts w/ BRAF V600E mutation
