Hypersensitivity

Question 1

Steps of developing Type I Hypersensitivity

Answer 1

1: Ag exposure
2: IgE cross-linking on mast cell
3: Histamine, leukotriene, PG, tryptase release
4: urticaria, rhinitis, wheezing, diarrhea, vomiting, hypotension, anaphylaxis

Question 2

Steps of developing type II hypersensitivity

Answer 2

IgM or IgG antibody destroys cells by opsonization, complement-mediated lysis, Ab-dependent cellular cytotoxicity

Question 3

Examples of type II hypersensitivity

Answer 3

ABO mismatch, Grave’s disease, myasthenia gravis

Question 4

Steps of type III hypersensitivity

Answer 4

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

Question 5

Examples of type III hypersensitivity

Answer 5

SLE, RA, farmer’s lung

Question 6

Steps of type IV hypersensitivity

Answer 6

1: Ag exposure activates sensitized T-cells
2: T-cell activation leads to tissue inflammation 48-96 hours after exposure

Question 7

Examples of type IV hypersensitivity

Answer 7

poison ivy rash

Question 8

What is rheumatoid arthritis?

Answer 8

systemic inflammatory disease affecting synovial membranes, granulation tissues develop in joint spaces and erode into articular cartilage and bone

Question 9

Clinical symptoms of RA

Answer 9

joint swelling, warmth, erythema, decreased ROM, morning stiffness > 1 hr; PIP, MCP, wrist, knees, ankles most commonly affected

Question 10

RA treatment

Answer 10

disease-modifying anti-rheumatid drugs, NSAIDs, steroids, physical theropy

Question 11

What is juvenile idiopathic arthritis?

Answer 11

collagen vascular disorder with persistent inflammation in 1 or more joints for 6 or more weeks in a patient <16 yo

Question 12

Presentation of juvenile idiopathic arthritis (JIA)

Answer 12

pauciarticular (large joints, asymmetric, iridocyclitis, uveitis), polyarticular (large and small joints), or systemic (recurrent, high fevers, myalgias, pericarditis, lymphadenopathy)

Question 13

Tests needed for diagnosis of JIA

Answer 13

CBC, ESR, RF/ANA, synovial fluid shows leukocytosis and elevated protein; diagnosis of EXCLUSION

Question 14

Treatment for JIA

Answer 14

NSAIDs, steroids, methotrexate, anti-tNF, stretching, morning baths, weight-bearing exercises

Question 15

What is systemic lupus erythematous (SLE)?

Answer 15

inflammatory disease most common in AA females, recurrent exacerbations and remissions, secondary to autoantibody formation and immune complex deposition

Question 16

SLE presentation

Answer 16

pleuritis, pericarditis, myocarditis, oral aphthous ulcers, arthritis, photosensitivity, positive ANA, lupus cerebritis, proteinuria, malar rash, discoid rash

Question 17

Important differences between SLE and RA

Answer 17

SLE: erosions are rare, morning stiffness lasts for minutes, deforming arthritis uncommon
RA: erosions are common, morning stiffness lasts for hour, deforming arthritis common

Question 18

SLE treatment

Answer 18

depends on systemic manifestations, steroids, disease-modifying antirheumatic drugs

Question 19

What is psoriasis?

Answer 19

chronic, hyperproliferative inflammatory disorder characterized by thick adherent scales

Question 20

Presentation of psoriasis

Answer 20

mild pruritis, salmon-pink plaques, extensor surface involvement, bilateral, nail pitting

Question 21

Psoriasis treatment

Answer 21

topical steroids, topical vitamin D, UV light, systemic immunosuppression

Question 22

Tests to diagnose psoriasis

Answer 22

history and physical exam (auspitz sign, pinpoint bleeding), biopsy

Question 23

What is multiple sclerosis?

Answer 23

demyelinating disorder of CNS, more common in females 20-40 yo

Question 24

Presentation of MS

Answer 24

vision changes, vertigo, weakness, numbness/tingling/pain, urinary incontinence, lhermitte’s sign

Question 25

Lhermitte’s sign

Answer 25

electrical sensation running down spine and lower extremities with neck flexio

Question 26

Diagnosis of MS

Answer 26

MRI, CSF

Question 27

Treatment of MS

Answer 27

immunomodulatory, immunosuppressive, IV steroids for acute exacerbations

Question 28

Types of primary immunodeficiencies

Answer 28

T-cell specific, b-cell specific, T-cell/B-cell combined, phagocytic disorders

Question 29

Characteristics of T-cell immunodeficiency

Answer 29

present in first 3-4 mo of life, disseminated intracellular diseases (DiGeorge)

Question 30

Characteristics of B-cell immunodeficiency

Answer 30

present after 6 mo, sinopulmonary and GI infections (CVID)

Question 31

Characteristics of T-cell/B-cell combined immunodeficiency

Answer 31

combination of T-cell and B-cell features (SCID)

Question 32

Characteristics of phagocytic immunodeficiency

Answer 32

sinopulmonary and soft tissue infections (Chediak-Higashi syndrome)

Question 33

Presentation of HIV/AIDS

Answer 33

initially asymptomatic, myalgias, fever, anorexia, headache, fatigue, pharyngitis

Question 34

Tests needed for diagnosis of HIV/AIDS

Answer 34

ELISA screen, western blot confirmation, HIV RNA viral load

Question 35

Treatment of HIV/AIDS

Answer 35

recommendation to screen pts between 13-64 at least once, depends on CD4 county, highly active antiretroviral therapy, prophylaxis of opportunistic infections

Question 36

AIDS diagnosis

Answer 36

CD4 count< 200 cells/mm3, presence of an AIDS defining illness (CMV, mycobacterium avium-intracellulare, candidal esophagitis)