Connective Tissue Flashcards
How does Gout look under the microscope?
Needle shaped crystals
Drugs that cause gout
(-) uric acid excretion: diuretics, low dose aspirin, ACEi, cyclosporine.
(+) production: Chemo
Rapid decline: Allopurinol, probenecid
Gout by hyperuricemia can be caused by:
-OH
-meat/seafood
-CKD
-drugs
Vitamin D metabolism
1.Sun activates 7-dehydrocholesterol -> Cholecalciferol
2. Liver dehydrolates it to 25-hydroxyVitD
3. Kidneys transforms it to 1,25-hydroxyVitD (active form)
Pt from Africa with bone pain which improves with exposure to sun. Think of
Vit D deficiency (rel with osteomalacia)
Paget disease phases and findings
- (Initial) Osteolytic: Osteoclast-dominant.
- Mixed: Osteoclast-osteoblast codominace. Areas of disorganized lamellar and woven bone
- Osteosclerotic: Osteoblast-dominant. Mosaic pattern of lamellar bone. Haphazardly oriented sections separated by prominent cement lines.
Osteonecrosis risk factors and signs
-SLE and Glucocorticoid user
-Chronic pain of groin, thigh or buttocks. Reduced motion pain
Differences between polymyositis and dermatomyositis
Poly: Endomisial inflam. No vascular involvement.
Derm: perifascicular inflam. Vasculopathy
Acute Reumatic Fever features
Migratory arthritis, fever, pancarditis (mitral regurgitation), history of recent strepto A pharyngitis. Positive Anti-streptolysin O titer
50 yo male, unable to straighten ring or little finger with similar family history. Think of
Depuytren contracture = progressive fibrosis of palmar fascia
Achilles Tendinitis presents with
Severe pain at the post aspect of the heel
Drugs that increase risk of osteoporosis and fx?
Anticonvulsants that activate P450, Aromatase inhibitors, GnRH agonists, glucocorticoids, Proton pump inhibitor, unfractioned heparin.
Rickets features
Frontal bossing, craniotabes, costochondral widening from overgrowth (rachitic rosary).
Rigor morris occurs due to
Failure of detachment of Myosin head from actin filament
Giant cell (temporal) arteritis is characterized by
-affecting >50yo
-affects arteries of head and neck
-Granulomatous inflammation
-Fragmentation of internal elastic lamina
-Rel to pain and stiffness I shoulders and hips (polymyalgia) and isquemic optic neuropathy
RA affects small joints but long term it also affects
Cervical spine causing spinal instability
What type of arthritis affects the sacroiliac joints and the Thoracic spine
Sacroiliac: seroneg spondyloarthropathies
Thoracic spine: osteoarthritis and spondyloarthritis
To prevent recurrent gout attacks, treat with
-Xanthine oxidase inhibitors (allopurinol, febuxostat)
-Uricosuric drugs (probenecid) are 2nd line but contraindicated in case of renal stones
To treat acute gout attacks, treat with
Cyclooxygenase inhibitors (NSAIDs), colchicine or glucocorticoids if not tolerated
Paget’s disease presents as
Old male pt
Deformity of long bones (pain) and skull (hearing loss)
Which factors are essential for osteoclastic differentiation?
Macrophage colony-stimulating factor (M-CSF)
Receptor activator of nuclear factor kappa-B ligand (RANK-L)
Landing on knee will likely injure which ligament?
Posterior ceuciate
Humeral neck fx can lead to
Disruption of retrograde blood flow from corcunflex arteries causing avascular necrosis
Gluteus medius main actions
Hip abduction
Pelvis stabilization during ambulation
Damages lead to gait instability (Trendelenburg +) weakness of abduction
Gluteus medius muscle inserts in
Greater trochanter of femur
Iliopsoas insertion and function
Lesser trochanter of femur
Hip flexor
Lyme disease phases
1.Early localized (days to weeks): flu-like sts, cutaneous eruption, erythema
2.Early dissemination (weeks to months): CNS problems (facial palsy), cardiac problems (nodal block)
3.late Lyme disease (months to years): asymmetric arthritis, encephalopathy
Lyme disease is treated with
Doxycycline or penicillin-type atb (ceftriaxone). Last one prevents progression
Drug induced Lupus E features
-arthralgia and serositis
-cutaneous, renal and neurologic complications are not common
-Antihistone antibody (+)
-anti-dsDNA (-)
Drug induced Lupus is usually triggered by
Isoniazid, procainamide, hydralazine. All have phase ll acetylation in liver
Which NSAIDs are a better option when there’s gastric ulcer history?
Specific Cox-2 inhibitors.
Cox-1 vs Cox-2
Cox-1: in Charge of gastric mucosal protection, platelet aggregation, (+) renal perfusion
Cox-2: (+) renal perfusion, vasodilation, tissue repair, inflammation, (+) pain sensitivity.
Sclerosis pathophysiology
- Vascular Endothelial cells produce endothelin-1 -> vasoconstriction, fibroblast activation and facilitates lymphocytes migration
-
T-lymphocytes-> increase cytokines->fibroblast activation
3.fibroblasts-> produce collagen -> skin thickening
Repetitive extension of the spine (like in gymnastics) can lead to
-Spondylolisthesis (vertebrae displacement
-Spondylolysis (fracture) Most commonly of pars interarticularis due to stress of vertebral post arch
Osteoporosis morphological characteristics
Trabecular bone thinning with loss of interconnecting bridges. Later on cortical bone is also affected
Ankylosing spondylitis presentation and dg
Pt <40yo, back/neck pain worsened by prolonged rest and improved by activity, stiffness
Dg with X-ray of pelvis (bony fusion) or Spinal x-ray (bridging syndesmophytes, bamboo spine) HLA-B27 is not dg
RA confirmation
Anti-cyclic citrulinated peptide (Anti-CCP) Highly specific. Measured via ELISA
What happens to muscle fibers when there’s reinnervation after denervation?
They go from forming checkerboard pattern (normal) to grouping together per type (two color patches).
Type I muscle fibers vs Type ll
Type I: slow, use oxidative phosphorylation, high myoglobin content, look red
Type ll: fast, use anaerobic glycolysis, low myoglobin, look pale
Most common carpal bone fx and complications
Scaphoid’s
Nonunion, avascular necrosis (retrograde blood flow interruption)
Dupuytren contracture
Progressive fibroproliferative disease of palmar fascia, draws fingers into flexion (ring finger)
Guyon canal sd
Compression of ulnar nerve typically due to fx of the hook of hamate (bone at base of little finger)
Sjögren features
Xerostomia, keratoconjunctivitis sicca.
Anti-Ro (+)
Periductal lymphocytic infiltrates of labial glands (inflammation of exocrine glands)
Deltoid flattening and insensitivity after blow to the arm is usually due to
Anterior shoulder dislocation (glenohumeral joint) Most common dislocation.
Axiliary N injury
A spiral Fx midshaft humerus commonly hurts
Radial nerve, Deep brachial artery
Redial nerve injury will affect which functions?
Forearm extension at elbow
Hand extension (causes wrist drop)
Sensibility to dorsal had, forearm and upper arm
Lateral epicondylitis vs medial
Lateral: due to repetitive wrist extension (tennis player’s elbow). Extensor carpi, radialis brevis and extensor digotorum insert in lat epicondyle
Medial: due to repetitive flexion (golf’s elbow).
RA pathogenesis
1.Rheumatoid agents-> activate T cells -> produce cytokines -> synovial hyperplasia-> increase HIG-1 -> angiogenesis -> synovium expansion-> pannus-> bony ankylosis, periarticular bone erosions (in arthrosis they’re marginal)
Which muscle in responsible for displacement in a distal clavicle fx?
Deltoid (originates on distal clavicle and inserts on humerus)
Which muscle stabilizes glenohumeral joint
Teres minor
Post and ant cruciate ligaments attach to
Post to the Medial femoral condyle (antlat surface)
Ant to the lat femoral condyle (postmedial surface)
Scoliosis features
-Dystrophin gene deletion
-affects mainly males (x-linked disease)
-Ambulation difficulties: clumsy march,waddling
-Gower sign: needs hands to stand up
-calf pseudohypertrophy: fibrofatty muscle replacement (advanced)
-Wheelchair bound by age 12
CKD causes decrease of vitD due to
-FGF23 increase -> inhibits 1-alpha-hydroxylase
-reduced GFR (less precursor reaches kidney)
-less renal mass and 1-alpha-hydroxylase
