DIT Rheum and Derm Flashcards
Endochondral ossification?
Chondrocytes make cartilage first (name makes sense). Osteoclasts and blasts then make WOVEN then LAMELLAR bone (after fractures or PAGETs you see woven)
Happens on long bones
Membranous ossification?
Osteoclasts and osteoblasts build without cartilage frame (skull and face)
What causes achondroplasia? Genetics?
FGFR3 (fibroblast growth factor receptor receptor) which inhibits chondrocytes (so no endochondrial ossification)
Mutations occur sporadically and associated with advanced paternal age. MUTATIONS then passed on autosomally dominant (makes sense b/c gene shuts down the gene)
Benign growth of bone growth in normal location is a what?
What does it look like on X ray?
Hamartoma. Osteochondroma.
CHunk of Bone osteoCHondroma
What is osteoclastoma? What do you see on X ray?
OsteoCLastoma is Clean so soap bubble
Soap bubble on X ray, osteoclasts broke down the matrix.
Giant cell tumor
What is the most common malignant bone tumor (not counting MM)?
Osteosarcoma and ages 10-20
What is location and X ray finding of osteosarcoma?
Knee or tibia
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X ray: osteoSarComa
Sunburst tumor (looks pretty, but will kill you)
Codman triangle (elevation of periosteum)
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Who gets Ewing Sarcoma?
Young boy
Where does Ewing sarcoma grow? What do you see on X ray?
Shaft of long bone.
Onion skin (can see layers of it) Can see bone being blasted away. (Patrick ewing smells like onion)
What is genetics of Ewing sarcoma?
t11:22 (easy to remember b/c Patrick Ewing’s number)
What metastasizes to bone?
PB KTL (lead kettle)
Prostate Breast Kidney, Testes/Thyroid, Lung
What is osteoclast from?
Monocyte/macrophage (they are multinucleate, will help with osteoclastoma recognition, multiple cells)
What is suffix of bisphosphanates? What do they do?
-dronate
Inhibit osteoclasts. Allows osteoblasts to catch up
Osteoparosis
Paget Disease of one
Humoral hypercalcemia of malignancy
Long term steroids
Side effects of -dronates?
Jaw osteoclastic activity (weird b/c normally stops it)
Erosive esophagitis
Parathyroid horomne agonist?
Teriparatide (mumble it and it sounds like teriparathyroid)
Teri ache won’t have issue
What is going on in osteopetrosis? How do you treat it (it makes sense!)?
Petrosis like petrified (greek for rock)
Carbonic anhydrase II deficiency (can’t make acid to break down bone) so bone keeps getting bigger.
Invades area for myeloid growth: pancytopenia.
Closes foramen so cranial nerve issues.
Marble bone and thickening. bone is easy to fracture
TX is marrow transplant b/c monocytes is where osteoclasts are from!!!
Labs of Pagets disease? Tx?
High alkaline phosphate b/c bone turnover
Tx is bisphophanates (-dronates) and that inhibits osteoclast!
Labs of osteomalacia?
low serum calcium
High parathyroid (to build up calcium b/c its Vit D deficient)
Low serum phosphate b/c PTH is PHOSPHATE THRASHING HORMONE
High alkaline phosphatase from bone turnover
pg 192 for more notes
ok
What are chondrocytes?
they maintain cartilage
What is unhappy triad?
Lateral collision with planted foot.
MCL
ACL
Lateral meniscus or medial (lateral more common, makes sense since that is what is compressed)
Hip dislocation can injure what?
Circumflex artery
Femoral vein
Femoral nerve
What tears first in ankle sprain?
ATFL Anterior talofibular ligament
ATFL (always tears first ligament)
What tears second, and third in ankle sprain?
Calcaneofibular Ligament
Posterior talofibular ligament
Rotator cuff muscles and function? Innervation?
SItS C5-6 Supraspinatus abduction Infraspinatus: lateral rotation Teres minor lateral rotation and adduct subscapularus medially rotate and deduction
Structures injured in anterior shoulder dislocation (3+STARS)
Axillary nerve and POSTERIOR circumflex artery (ask if sensation to shoulder so you know when injury happens if it hurts after reduction)
Supraspinatus tendon
Anterior glenohumeral ligament and labrum
Posteriolateral humeral head defect from abrasion against anterior rim of glenoid
Punch with closed fist and tenderness in snuffbox?
Scaphoid fracture regardless of x ray!
Can result in painful arthritis if not fixed b/c distal to proximal blood flow
What finger joints are involved in osteoarthritis?
PIP (bouchard nodes)
DIP (heberden nodes)
NO MCP!!!
3 uses for N-acetylcysteine?
NAC (nephropathy, acetominophen OD, Cystic fibrosis)
Acetaminophen OD (regen glutathione)
Mucolytic (CF)
Nephropathic use of contrast
What joints are involved in rheum?
MCP and PIP. Ulner drift
there is no DIP
What type of hypersensitivity is RA?
Type III (some type IV according to first aid)
Serum test for rheumatoid arthritis? Which is specific?
Rheumatoid factor (IgM anti IgG)
Anti-cyclic citrullinated peptide is specific
Disease modifying agents for Rheum Arthritis?
Methroterxate, sulfasalazine, TNF alpha inhibitors (etanercept, infliximab, adalimumab, golimumab, certolizumab)
Gout crystals are what? What do they look like? Why do people have gout?
negative Berfringent. so Not Blue when parallel, instead Parallel to light are yellow (l’s in yellow are parallel)
They are uric acid
More eating of purine foods
Less excretion of uric acid (diuretics)
Lesh-Nyhan
Treated for leukemia/lymphoma
What are 2 things that can precede a gout attack?
Large meal
Alcohol consumption (b/c alcohol fights for uric acid for sites of excretion in kidney)
Acute gout tx? Mechanism for each?
NSAIDs (indomethacin is tx of choice): COX inhib
Steroids (a few days worth): inhibit NFkappa B
Colchicine (rarely used): Low therapeutic index and diarrhea is common. Prevents microtubule polymerization
Chronic gout tx? And mechanism?
Allopurinol inhibits xanthine oxidase (so does febuxostat)
Probenecid: inhibits reabsorption of uric acid in proximal convoluted tubules (also blocks penicillin uptake, so fun fact is they used it during shortages during WWII)
What are psuedogout crystals? What do they look like? how do you tell from gout? How do you treat?
They are calcium pyrophosphate.
They are positive Berfringent so Blue when parallel to light (gout was yellow, so its different)
Bigger joints. older people
Tx is same with NSAIDs and if bad, steroids/colchicine
Calcification of cartilage in knee suggests what?
pseudogout (+ berfringent of light would be Blue to parallel crystals)
What are the HLA B27 associated Disease?
PAIR.
Psoriatic arthritis
Ankylosing spondylitis
Inflammatory bowel disease
Reactive arthritis (Reiter syndrome)
What disease has pencil in cup on Xray?
PIP is malformed in PSORIATIC arthritis.
Also see sausage fingers.
Sacroiliac joints are fusing? What is the disease?
If you see that, think ANKYLOSING spondylitis
Improves with exercise. Reduced spine mobility
What risks come with ankylosing spondylitis?
fusion of vertebrae
sacroiliac joint ankylosis
uveitis
AORTIC REGURGE
What is reactive arthritis?
HLA B27 associated and after a Chlamydia infection
GI infection: shigella, salmonella, yersinia, campylobacter, clostridium
Traid:
Cant see
Cant pee
Can’t climb a tree
What is etanercept?
TNF alpha decoy reCEPTor (etanerCEPT)
What is osteitis fibrosis cystica?
Excess PTH causes bone break down (hyperparathoiridism or pseudohypoparathyroidism (b/c renals don’t recognize PTH))
What is benztropine used for?
antimuscarinic used in PARKINSONS
PARK my BENZ
What are anti-histone antibodies?
Drug induced lupus (SHIPP)
Sulfonamides Hydralazine Isoniazid Phenytoin Procainamide
Antiphospholipid antibodies mean what?
Associated with lupus, cause hyper coagulation (false positive from syphilis)
Diffuse scleroderma vs limited scleroderma? What is serology?
Diffuse: Anti-Scl-70 (anti-DNA topo1). Widespread involvement and progression to viscera
Lmited: antiCentromere (C for CREST) (more benign) Calcinosis Raynaud Esophageal dysmotility Sclerodactyly Telangiectasia
Sjogrens triad?
Dry eyes
Dry mouth
Arthritis
Cana’t see
Cant spit
Cant climb up shit
Pseudohypertrophy of calf cause?
Duchenne. Frameshift of dystrophin gene (X recessive)
Also Gower’s maneuver
Also Beckers is just a mutation in gene and not as severeL
Little old lady with fever and stiffness in shoulder and hip with weight loss. No muscular weakness?
What are labs? What are tx?
Polymyalgia rheumatica
Higher ESR, normal CK (b/c no muscle breakdown)
Tx is steroids
Pain and weakness (mostly weakness) of proximal muscles suggests what?
What is causing it?
How do you Dx?
(b/c proximal, think myositis b/c bigger muscles and more chance for pathology (if it were distal think nerve b/c longer nerves more chance for pathology)
CD8 T cell induced injury to muscles often in shoulder or hip
Muscle biopsy, elevated CK (muscle breakdown), ANA, anti Jo-1
FDA approved for fibromyalgia?
Pregabalin (nerve pain decreased)
Minlacipran (similar to SSRI)
AntiSmith?
SnRP in lupus
Anti-centromere antibodies?
CREST scleroderma
Anti0topo antibodies?
Diffuse scleroderma (Scl70(
Anti-Jo-1 antibodies?
Polymyositis/Polydermositis
Anti-Ro
sjogren
Fascial rash, raynaud in a young woman?
lupus
Arthritis, dry mouth, dry eyes?
Sjogren
Cant see
can’t spit
can’t climb shit
epiderm layers? Mnemonic alert
Californians Like Girls in String Bikinis
stratum Corneum Stratum lucidum stratum granulosusm stratum spinosum stratum basale
dermis
Zona occludes is what?
tight junction
What is zonula adherens? what does it do?
It is below tight junction
Actin connected to adjacent cells with CADherens (Ca++ dependent Adhesion proteins)
Losing E cadherin promotes metastasis
What is the macula adherens?
Desmosomes (Macula adherents is Desmosome: MAD (MAD is PVD pretty violent dog from sms mnemonic i made). Support by keratin interaction. Pemphigus vulgaris hits it
What makes up gap junction?
connexon
What does bullous pemphigoid hit?
Hemidesmosomes. Bullous pemphigoid is below
How do you treat atopic dermatitis?
Eczema
moisturize Calcineurin inhibitors (tacrolimus or pimercrolimus RMEMBER) topical steroids antihistamines leukotrinee inhibitors UV If severe: systemic steroids
What is a freckle?
higher concentration of melanin (NOT higher concentration of melanocytes!)
4 parts of pathophys of acne? Tx for each?
Hyperkeratosis: Retinoids
Sebum overproduction (grease): Isotretinoin, SPIRONOLACTONE (anti androgen) OCPs
Propionibacterium acnes prolif: Clindamycin, Benzoyl peroxide, erethryomycin
Inflammation: steroids if big event (short term works, but long term makes worse)
Parakeratotic scaling?
Nuclie in stratum corneum. PSORIASIS
Also see more spinosum (pSoriasis)
Also see less granulosum
Psoriasis extra findings?
Auspitz sign
nail pitting
psoriatic arthritis (pen in cup)
Causes of albinism?
Decreased melanin production b/c less tyrosinase
Vitiligo is caused by what?
Autoimmune destruction of melancytes
What is melasma caused by?
in preggers (mask of pregnancy) or OCP
What causes impetigo?
S. auereus and s pyogenes
Whatis cellulitis and what causes it?
Acute painful infection of dermis and subQ tissue. S progenies and S aureus
What cause necrotizing fasciitis?
S pyogenes or anaerobic bacteria.
Crepitus is methane and CO2 production
Staphylococcal scalded skin syndrome is caused by what?
What do you see?
Who has it?
Exotoxin A and B will destroy stratum granulosum keratinocyte attachments.
Fever
Erythematous rash
SLOUGHING of skin!!
Children
What is hairy leukoplakia caused by? Symptoms?
White and painless plaques on tongue that can’t be scraped off.
EBV in HIV positive patients
Pemphigus vulgaris is attacking what?
Symptoms
MAD.
Macula Adhereins (Desmosomes)
Flaccid blisters
Oral lesions
PAINFUL Blisters
Nikolsky sign is separation of skin by stroking skin!!!
Menmonic for pemphigus vulgaris?
DAMN is a Vulgar word
Desmosomes (macula adherins)
Acantholysis
Mouth
Nikolsky’s sign
How to tell bullous pemphigoid apart from pemphigus vulgarism?
Hemidesmosomes on stain instead as it is BULLOW the dermis
Tense blisters instead of flaccid
No nikolski sign (not as severe)
Mouth sparing (not as severe)
Symptom of dermatitis herpetiformis? Caused by what?
IgA in dermal papillae. Associated with celiac.
Pruritic papules, vesicles and bullae (arie!)
What is erythema multiform?
Associated with infections, drugs, cancer or autoimmune.
They are target lesions from deposition of immune complexes depositing in ORAL or superficial skin vessels!
can become steven-johnson
What causes Steven Johnsons?
Seizure meds
Sulfa meds
Penicillins
Allopurinol (outlier)
What is Toxic Epidermal Necrolysis?
TEN is 30% or more of body are involved
What is mnemonic for lichen plans? What is the his to?
6 P’s
Pruritic Purple Polygonal planar apules Plaques Planus
Sawtooth infiltrate of lymphocytes at dermal-epi junction. (hepatitis C)
What is actinic keratosis?
Premalignant from sun exposure you can feel better than see. 5 FU is treatment
Acanthosis nigricans is what?
Epidermal hyperplasia making hyper pigmented area on neck or axilla.
Hyperinsulinemia )diabetes, obesity, cushing) canc asue it
Rarely malignancy, probs diabetes
Erethema nodosum?
Inflam of subcu fat. Painful.
Can see with Crohn’s disease and infections or SARCOID
(stre, leprosy, TB, histo, coccidio)
What has a herald patch before christmas tree?
Pityriasis rosea
Most common skin cancers in order? What is order of metastasis?
Basal, Squamous, Melanoma for frequency.
Malignancy is reversed
Keratin pearls on histopathology?
Squamous cell carcinoma.
Rarely metastasizes but can be locally invasive and make lesions!
What skin issue can have pearly nodules with telangiectasia and rolled borders and potential ulceration (bumpy but well defined)
Basal cell carcinoma
What has palisading nuclei on histopathology?
Basal cell carcinoma (basal cells are palisading up!)
What does S-100 mean?
neural crest derivative (so in melenoma)