Hypersensitivity Flashcards
Steps of developing Type I Hypersensitivity
1: Ag exposure
2: IgE cross-linking on mast cell
3: Histamine, leukotriene, PG, tryptase release
4: urticaria, rhinitis, wheezing, diarrhea, vomiting, hypotension, anaphylaxis
Steps of developing type II hypersensitivity
IgM or IgG antibody destroys cells by opsonization, complement-mediated lysis, Ab-dependent cellular cytotoxicity
Examples of type II hypersensitivity
ABO mismatch, Grave’s disease, myasthenia gravis
Steps of type III hypersensitivity
1: Ag-Ab complex formation
2: complexes activate complement and neutrophil infiltration of tissue
3: tissue inflammation leading to symptoms of fever, urticaria, generalized lymphadenopathy, arthritis, vasculitis
Examples of type III hypersensitivity
SLE, RA, farmer’s lung
Steps of type IV hypersensitivity
1: Ag exposure activates sensitized T-cells
2: T-cell activation leads to tissue inflammation 48-96 hours after exposure
Examples of type IV hypersensitivity
poison ivy rash
What is rheumatoid arthritis?
systemic inflammatory disease affecting synovial membranes, granulation tissues develop in joint spaces and erode into articular cartilage and bone
Clinical symptoms of RA
joint swelling, warmth, erythema, decreased ROM, morning stiffness > 1 hr; PIP, MCP, wrist, knees, ankles most commonly affected
RA treatment
disease-modifying anti-rheumatid drugs, NSAIDs, steroids, physical theropy
What is juvenile idiopathic arthritis?
collagen vascular disorder with persistent inflammation in 1 or more joints for 6 or more weeks in a patient <16 yo
Presentation of juvenile idiopathic arthritis (JIA)
pauciarticular (large joints, asymmetric, iridocyclitis, uveitis), polyarticular (large and small joints), or systemic (recurrent, high fevers, myalgias, pericarditis, lymphadenopathy)
Tests needed for diagnosis of JIA
CBC, ESR, RF/ANA, synovial fluid shows leukocytosis and elevated protein; diagnosis of EXCLUSION
Treatment for JIA
NSAIDs, steroids, methotrexate, anti-tNF, stretching, morning baths, weight-bearing exercises
What is systemic lupus erythematous (SLE)?
inflammatory disease most common in AA females, recurrent exacerbations and remissions, secondary to autoantibody formation and immune complex deposition
SLE presentation
pleuritis, pericarditis, myocarditis, oral aphthous ulcers, arthritis, photosensitivity, positive ANA, lupus cerebritis, proteinuria, malar rash, discoid rash
Important differences between SLE and RA
SLE: erosions are rare, morning stiffness lasts for minutes, deforming arthritis uncommon
RA: erosions are common, morning stiffness lasts for hour, deforming arthritis common
SLE treatment
depends on systemic manifestations, steroids, disease-modifying antirheumatic drugs
What is psoriasis?
chronic, hyperproliferative inflammatory disorder characterized by thick adherent scales
Presentation of psoriasis
mild pruritis, salmon-pink plaques, extensor surface involvement, bilateral, nail pitting
Psoriasis treatment
topical steroids, topical vitamin D, UV light, systemic immunosuppression
Tests to diagnose psoriasis
history and physical exam (auspitz sign, pinpoint bleeding), biopsy
What is multiple sclerosis?
demyelinating disorder of CNS, more common in females 20-40 yo
Presentation of MS
vision changes, vertigo, weakness, numbness/tingling/pain, urinary incontinence, lhermitte’s sign
