Skin/MS Pathology Flashcards
Trendelenberg sign
dropping of the lifted legs hip
Due to paralysis of the abductors of gluteus medius and gluteus minimus-> Superior gluteal invervation
Foot drop
Peroneal nerve damaged
dorsiflexes and everts the foot
PED
Can’t stand on tip toes
Tibial nerve damage
inverts and plantaflexes the foot
TIP
Thigh adduction innervated
- anterior hip dislocation
(4 muscles)
Obturator
adductor longu, adductor, brevis, anterior portion of adductus magnus, gracilis
Thigh flexion and leg extension nerve
Femoral
worry in pelvic fracture
Knee trauma worry about this nerve
Can
tibial
posterior hip dislocation and can’t jump
nerve and muscle
inferior gluteal enervating the gluteus maximus
pathology due to activating mutation in fibroblast growth factor receptor 3 (FGFR3)
Achrondroplasia - dwarfism
Achodroplasia
imparied cartilage proliferation in the growth plate
Dwarfism
Endochondrial bone formation
formation of bone via cartilage matrix which is replaced -> implicated in achondroplasia
Intramembranous bone fomration
formation of long bone w/out preexisting cartilage matrix - > flat bone formation (Skull and rib cage) thus why normal head in dwarfism
3 signs of osteogenesis imperfecta
multiple fractures (thinking child abuse)
Blue sclera
hearing loss
Thinning scleral collagen revealing choroidal veins
Defect in?
Blue sclera - in osteogenesis imperfecta
thing Autosomal defect in collagen type 1
Osteopetrosis is what and due to what?
inhereted defect in bone resorption -> abnormally thick and heavy bone
due to poor osteoclast activity - like carbonic anhydrase II mutations
Carbonic anydrase II mutatio nleads to
Osteopetrosis
can’t make acidic environment to resorb bone - osteoclasts do not work as well
Renal tubular acidosis w/ bone fractures is connected how?
lack of carbonicanhydrase II activity - osteopetrosis
- Normal enzyme activity leads to pumping of H in the lumen of tubules as NH4 and bicarb in the serum, lack of enzyme -> acidosis
myelopththisic process due to?
What causes?
Bone fractures
vision and hearing impairment
hydrocephalus
bone thickens out the marrow region leading o anemia, thrombocytopenia and leukopenia, as sen in osteoporosis
hearing and vision loss w/ nerve impingement
hydrocephalus w/ foramen magnum oclusion
Rx for psteopetrosis works how?
give bone marrow transplant so you have new source for monocyte derived osteoclasts
Defective mineralization of osteoid is called ?
Due to ?
rickets/ osteomalacia
due to VIt D deficiency, osteoblasts make osteoid but not mineralized
Active Vit D does what?
3 things
raises serum Ca and phosphate levels by acting on
intestine - increase absorb of Ca and phos
kidney - increase resorb of Ca and phos
bone - increase resorb of Ca and phos
1 alpha hydroxilation occur where after what>
in the proximal tubule of the kidney after 25 hydroxylation of Vit D
Frontal bossing, pigeon breast deformity, archaic rosary and what other symptom cause ?
What age group
Rickets in kids less than one
Usually also see bowed legs
Frontal bossing - large forehead
pigeon breast - inward bending of the ribs w/ anterior protrusion
rachitic rosary - ostoid deposition at chostochondral angle
low serum Ca and phos w/ increased PTH and alk phos seen in ?
Osteomalacia
Most common forms of osteoporosis (2)
senile - old age leads to loss of bone mass naturally w/out exercise or diet
postmenopause - lose of estrogen
Labs in osteoperosis
Serum Ca, phosphate, PTH and alk phos are NORMAL
Mosaic pattern on lamellar done is called?
Due to
Paget disease of the bone
Due to imbalance of osteoclast and osteoblast function in later 60s
Clinical features of pagets disease? (4)
Labs
bone pain - improper bone formation
hearing loss -impinged CN8
lion like facies
increasing hat size
- isolated alk phis levels due to isolated osteoblast activity post osteoclast activation (maybe viral)
Bisphosphates work in osteoporosis and Pagets due to
inhibition apoptosis of osteoclasts
Can also give calcitonin in pagets
2 complications in pagets
osteosarcoma - mutated cancerous osteoblasts
high output cardiac failure - AV shunts in bone -> high pressure
2 locations of osteomylitis in adults and kids
causes?
metaphysis in kids due to transient bacterium
epiphysis in adults due to open wounds
6 organisms implicated in osteomylitis
staph aureus - most common N gonorrhea - sexually active Salmonella - sickle cell pseudomonas - Diabetics and IV use pasteurella - Cat and dog bites mycopbaterium tuberculosis
Potts disease
TB and bone vertebrae implicated osteomyolitis
Cat and dog bites or scratches and you have osteomylitis caused by
pasteurella
Diabetics and IV drug use predispose this infectious organism for osteomyolitis
pseudomonas
Lytic focus of necrosis surrounded by sclerosis on x ray
clinical features?
osteomyolitis
Bone pain w/ fever and leukocytosis
Ischemic necrosis of the bone or marrow ->
Causes? (4)
avascular aseptic necrosis
Trauma
steroids
sickle cell anemia (dactelitis)
caisson disease - (gas emboli)
Gardner Syndrome (3)
Familial adenomys polyposis
fibromitosis in retroperitoneum
osteomas of the facial bone
bening tumor on the surface of facial bones
osteoma
young adult (<25) comes in w/ a tumor on the cortex of his long bone (the diaphysis)
x ray will reveal
osteoid osteoma
bony mass w/ radiolucent core - (osteiod)
Osteoblastoma differs from osteoid osteoma 3 ways
larger than 2cm
arises from the vertebrae - vs cortex of long bones
does not respond to ASA
Give ASA for bone pain w/ what tumor
osteoid osteoma
benign tumor of osteoblast
most common benign tumor of the bone grows where
Osteochdroma browns as a lateral projection of the growth plate - metaphysics
Osteochondroma concerns
transforms to chondosarcoma w/ overlying cartilage cap
Sunburst appearance and lifting of the periosteum -> cowman triage seen where?
Peak incidence?
in osteosarcoma
in teens and elderly
Osteosarcoma arises where?
Similar to
metaphysis of long bones - usually distal femur and proximal tibia
giant cell tumor except epiphysis
Risk factors for osteocarcoma (3)
familial retinoblastoma - teen
paget disease - elderly
radiation exposure - elderly
pleomorphic cells that produce osteoid seen on histology
osteosarcoma - malignant
Unique feature of giant cell tumor
only bone tumor arising in the epiphysis of long bone
- tumor comprised of multinucleated giant cells and stromal cells
Soap bubble appearance on x ray w/ a young adult
giant cell tumor
- locally aggressive and may recur
onion skin on x ray in a map child less than 15
ewing sarcoma
periosteum laying down new bone that is circumferentially compressed
malignant proliferation of poorly differentiated cells from neuroectoderm
Ewing sarcoma cells derived from
neuroectoderm
May present METS but highly treatable
small round blue cells that resemble lymphocyte differential in diaphysis of long bone (3)
Can have fever
Ewing sarcoma - 11:22 translocation
osteomylitis
lymphoma
11:22 translocation
Ewing sarcoma
Cartilage tumors usually arise from?
medulla of the of bone
small bones of the hand present w/ tumor
chondroma
tumor of medulla of the pelvis or central skeleton
chondrosarcoma
Most common bone tumor
See?
METS
See osteolytic punched out lesions
- EXCEPT prostate and breast cancer -> sclerosis and osteoblastic lesions (breast is also lytic)
Articular surface lining the synovial joint is made of what
What is secreted by synovium
hyaline cartilage type II
fluid rich in hyaluronic acid
Progressive degeneration of articular cartilage is what?
Affects which joints?
Osteoarthritis
DIP*, PIP, hips, lower lumbar spine, knees
Joint stillness in the morning that gradually gets worse throughout the day
Pathologically see (3)
Osteoarthritis
- joint mice- cartilage breaks into the synovium
- ebunartion or polishing of sub chondral bone
- osteophyte formation in the DIP
heberden nodes
DIP osteophite formation
Bouchard node
PIP osteophite formation
HLA DR4
Seen in rheumatoid arthritis
Synovitis leading to the formation of a pannus
Rhuematoid arthritis
inflammation -> grannulation tissue w/ associated fibroblasts, blood vessels and myfibroblasts (deviation and ankylosis)
See joint narrowing, loss of cartilage and osteropenia on X Ray
ankylosis
fusion - seen in rheumatoid arthritis
morning stiffness that improves w. activity
Rheumatoid arthritis
Break gown granulation tissue that build up over night throughout the day
Which joints are spared in RA
DIP
Symmetrical involvement otherwise
Clinical features of RA? (6)
Arthritis fever, malaise, weight loss Rheumatoid nodules Vasculitis bakers cyst Pleural effusions, LAD, intersitial lung fibrosis
Lab findings of RA
found in fluid
IgM autoantibody agianst Fc portion of IgG
Rheumatoid factor
See PMNs and high protein
Complications of RH(2)
Anemia due to chronic disease
secondary amyloidsosis, acute phase reactants SAA-> AA deposited
HLA B27
Seronegative spndyloarthritis
Seronegative Spondyloarthritis (3)
Meaning?
Ankylosing spondyloarthritis
Reiter syndrome
Psoriatic arthritis
Means lack of RA factor, HLA B27 and Axial skeleton involvement
Bamboo spine
Presentation and target group Extra articular (2)
ankylosing spondyloarthritis
young adults usually males w/ low back pain -> fusion of vertebra
Uveitis(red eye/blind)
aoritis (potential aneurism and regurgitation)
Reitor syndome qualified by (3)
Seen when
Urethritis, conjunctivitis, arthritis
-Cant see, can’t pee, can’t climb a tree
Post GI or chylamidia trachomatis infection
Sausage fingers/toes
Seen in sporadic arthritis - 10% of psoriasis
Axial and peripheral joints and DIP commonly
Infectious arthritis presentation and causal agents (2)
N gonorrhoeae - young adults
S aureus - older children and adults (2nd most common)
Single joint usually the knee
- warm joint w/ limited range of motion fever, leukocytosis and elevated ESR
Gout is due to generally -
hyperuricemia
Hyper purine metabolism or decreased excretion by the kidney
2 types of Gout (2; 1 and 3)
Primary - unknown cause due to hyper urea production and deposition of monosodium in tissues
Secondary
- Leukopenia and myeloproliferative disorders
- Lesch nyhan syndrome
- renal insufficiency
Deficiency in what enzyme leads to symptoms of mental retardation and self mutilation
Lesch Nyhan syndrome
- missing hypoxanthine guanine phosphoribosyltransferase
-> rescues hypoxthanthine and guanine before they are converted by xanthine oxidase xanthine and ultimately uric acid
Acute inflammatory reaction that is precipitated by consumption of alcohol or meats
Acute gout - commonly affects the big toe (podagra)
alcohol- slows excretion
meats - throws more purine into the system
tophi is made of what?
Associated w/
white chalky aggregates of uric acid crystals and fibrosis and giant cell reaction
- Chronic gout
Chronic gout leads to
renal failure w/ deposition of crystals in the kidney tubules
negative birefringence under polarized light
yellow, needle shaped, associated w/ hyperuicemia gout
rhomboid-shaped crystals w/ positive birefringence under polarized light
pseudogout
due to calcium pyrophosphate dihydrate deposition
malar rash w/ ANA and bilateral proximal muscle weakness
Dermatomysitis
NOT SLE
Clinical features of dermatomyositis (1 +3)
bilateral proximal muscle weakness-> distal weakness (can’t comb hair can’t climb stairs)
Rash on
- upper eyelid (heliotrope, purple)
- malar rash
- red papules on elbows, knuckles and knees
Anti jo 1 antibody
See also in lab (2)
dermatomyosisits
Also have ANA and increase creatine kinase
Perimysial inflammation (CD4 T cells) w/ perivascular atrophy
Dermatomyositis
- periphery of fascicle - closer to skin…(rashes)
differs from polymyositis w/ inflammation of endomysial inflammation w/ CD8
Polymyositis
-pathophys?
bilateral proximal muscle weakness w/out skin rash
- endomysial inflammation w/ necortic muscle fibers on biopsy
What needs to be ruled out with dermatomyositis?
underlying carcinoma especially gastric carcinoma
X linked muscular dystrophy(2) is due to what?
Duchenne -deletion of dystropin gene
Becker - mutation of dystropin gene
Dystophin is implicated in what and important for what?
in x linked muscular dystrophy
important in anchoring muscle cytoskeleton and EC matrix
Kid presents w/ calf that feels fatty around 1 yrs old
muscular dystrophy - X linked
Calf pseudohypertrophy
aslod find elevated serum creatine
distal muscles overworked when learning to walk and eventually replaced w/ fat (dystrophy)
cause of death in duchenne dystophy
due to replacement of myocardium or diaphragm w/ fat and have cardiac or respiratory failure
mutated dystophin leads to
beckers muscular dystophy, still have some protein made -> milder disease
presentation of muscle weakness that gets worse w/ use especially the eye (ptosis and diplopia)
pathophys?
Myasthenia gravis
Autoantobodies to the postsynaptic ACh receptor at the neuromuscular junction, less ACH w/ repeated use -> less ability to overcome the Ab blockade
Rx strategy in myasthenia gravis
acyetycholinesterase inhibitors -> more ACh around
Does not work in Lambert Eaton Syndrome due to lack of ini alt ACh w/ AB against the Ca channel
Association w/ myasthenia gravis and action?
thymic hyperplasia or thyoma
removal -> improvement in symptoms
Proximal muslce weakness that gets better w/ use and eyes are NOT affected
Patho-phys
Lambert Eaton Syndrome
Autoantibodies against the Ca channel presynaptically preventing depolarization and ACh release
Symptoms improve w/use due to increased Ca gradient -> eventual overwhelming of Ab
Lambert Eaton Syndrome etiology
due to paraneoplastice syndrome - often small cell carcinoma; resolves w/ removal
Lipoblast are characteristic of?
liposarcoma - most common malignant soft tissue tumor;
most common soft tissue tumor in adults benign
lipoma
Cardiac rhabdomyoma is associated w/ what syndrome
tuberous sclerosis
Rhabsomyoma - benign tumor of skeletal muscle
malignant skeletal muscle tumor?
Patient population and common site?
rhabdomyosarcoma
most common in kids
-vagina in girls; head and neck
rhabdomyoblast characteristic of ?
what is the name of the intermediate filament associated w/?
rhabdomyosarcoma
desmin
Layers of the skin top to bottom (4)
Stratum corneum
Stratum ganuosu,
Strum Spinosum
Stratum basalis
atopic dermatitis (eczema) location and description
flexor regions,
puritic erythematous oozing rash w/ vesicles and edema
Eczema is often associated w/
asthma and allergic rhinitis
Type 1 hypersensitivity
Contact dermatitis location and description
differs from eczema?
Where contact w/ allergen - poison ivy, nickel, drugs, irritants
puritic erythematous oozing rash w/ vesicles and edema
differs in type IV hypersensitivity
Comedome vs pustule vs nodule
comedome - white head/ black head blockage w/ excessive sebum and keratin production
Pustule/pimple is inflammation
nodule is scarred pustule
infectious agent in acne
MOA
proptionibacterium acnes
produces lipases that break down sebum releasing pro inflammatory FA
Rx for acne
benzoyl peroxide - antimicrobial
Vit A Isotretinoin - maintains specialized epithelial cells
Psorisis location and descripition
well circumscribed salmon colored plaque w/ silver scales
Extensor surface and scalp
may see pitting nails
HLA -C and areas of trauma
associated w/ triggering of psoriasis
Acanthosis
epidermal hyperplasia - psoriasis
parakeratosis
hyperkeratosis and retention of keratinocyte nuclei
-psoriasis
munro microabcesses
collection of PMNs in the stratum corneum
elongated dermal papillae the has thinned epidermis and picks when bleeds
auspitz sign
- psoriasis
5 Ps in Lichen Plansus
Puritic Planar Polygonal Purple Papule
Lichen Plansus normally attacks the (3)
wrists
elbos
oral mucosa - Wickham striae - reticular white lines)
Wickham striae -
reticular white lines of the oral mucosa in lichen planus
sawtooth appearance at the dermal epidermal junction
Associated w/ what infection
lichen planus
Chronic Hep C
autoimmune destruction of demosomes called?
occurs where?
pemphigus vulgaris
IgG attacks desmoglein (type II hypersensitivity) - separation of stratum spinosum
Skin AND oral mucosa
autoimmune destruction of hemidemosomses called?
Occurs where?
bullous pemphigoid
IgG attacks the hemidesmosome component of BM (BP180)
Only in the skin
Acantholysis
Separation of stratum spinsosum keratinocytes -> subrabasal blisters
pemphigus vulgaris
Nikolsky’s sign
Immunofloresence
thin walled bullae that easily rupture - does not include the BM w/ desmosome IgG attack
-> shallow erosions w/ dried crust
Seen in pemphigus vulgaris
Fish net w/ IgG attacking the desmosome,
Tense bullae that do not rupture, autoimmune disease of the skin
Immunoflorescene?
Bullous pemphigoid
Linear IgG Attacking the BM
Deposition of IgA at the tips of the dermal papillae?
Often due to ?
Dermatitis herpetiformis
- vesiculal lesions
Celiac
dematitis herpetiformis presentation (2)
puritic vesicles and bollae grouped - herpetiform
Targetoid rash and bullae that may be seen after a drug (penicillin) given is called?
erythema multiform
targetoid w/ central epidermal necrosis