Immunopathology

Question 1

Type 1 Hypersensitivity

Answer 1

IgE Ab mediated: allergy or antiparasite activity

Activation of Mast Cells: increase vascular permeability

Question 2

Atopy

Answer 2

familiar predispostion to developing a particular allergen

Question 3

Signs and Sx of Type 1 HS

Answer 3

Allergic conjuctivitis
Allergic Rhinitis
Atopic dermatitis (eczema)
diarrhea and cramping

Question 4

Hypersensitivity to wasp/bee/hornet sting

Answer 4

Type 1:
Anaphylaxis to bee sting
urticarial swelling, wheezing, laryngeal swelling, obstruction
Tx: immediate SQ injection of Epi

Question 5

Type II: Cytotoxic HS Disorder

Answer 5

Ab mediated cytotoxic reaction involving complement activation
causing lysis, recruitment of immune cells, NK cells, Autobs agains receptors

Examples of causes: ABO mismatch, transplant rejection, Goodpasture syndrome, Rheumatic fever, Newborn Rh hemolytic disease, Myasthenia Gravis, Graves disease

Question 6

Type III: Immunocomplex Hypersensitivity Disorder

Answer 6

deposition of circulating complexes of Ag bound to IgG or IGm in target tissue with subsequent complement activation:
–neutrophils and macrophage damage tissues
*arthus reaction
Farmers lung
Serum Sickness

Question 7

Arthus Reaction

Answer 7

Type 3 HS

-local immunocomplex deposition causing vasculitis

Question 8

Serum Sickness

Answer 8

Type 3 Hs

fever, urticarial rash, generalized lymphadenopathy, arthritis, glomerulonephritis, vasculitis

Question 9

Farmer’s Lung

Answer 9

Type 3 HS
exposure to actinomyces antigen in the air causing antibodies to form in the lungs

-Re-exposure produces local immunocomplex formation in lung intersitium
granulomatous inflammation occurs later: Type 4 HS

Question 10

Type 4 HS

Answer 10

T cell mediated: cellular immunity:

• AB not required in any of these reactions
• -Allergic contact dermatitis: pre-exposed then reexposed
• -PPD skin test for TB
• -cell mediated response to intracellular pathogens with granuloma formation: late phase farmer’s lung

Question 11

Rheumatoid Arthritis

Answer 11

• Typical onset: Age 30-50
• Risk factors: women, smokers, family hx
• typical presentation: pain and stiffness in multiple joints, typically wrists and joints of hand
• DIPS usually not impacted by RA
• *Morning Stiffness lasting more than 1 hour suggests inflammatory etiology

ROS : fatigue, weight loss, anemia

Question 12

Differential Dx for RA

Answer 12

Systemic lupus erythematosus, systemic sclerosis, psoriatic arthritis, sarcoidosis, crystal arthropathy, and spondyloarthropathy

Question 13

RA Tx

Answer 13

first line: Methotrexate
(Methotrexate my not be appropriate for patients with increased risk of hepatotoxicity: alcohol abuse and fatty liver disease)
DMARDS: leflunomide, plaquenil, sulfasalzine

glucocorticoids if disease activity is high
-lowest possible dose of prednisone

**Treat Early
Goal to Tx: remission ro lowers disease activity

Question 14

Juvenile Rheumatoid Arthritis

Answer 14

Children present w/ painless joint inflammation
normal results with rheumatologic tests
-present with limp
must last 6 weeks in at least 1 joint and exclusion of other symptoms in a person under age 16
morbidity: idopathic inflammatory eye disease

Question 15

JRA Dx

Answer 15

diagnosis of exclusion
r/o lyme disease, leukemia, infection of bone or joint, psoriasis, IBD, Strep

lab tests don’t help you…clinical judgement

Question 16

Systemic Lupus Erythematosus

Answer 16

Risk factors: black person, female
recurrent sx: with periods of flares
*fatigue, weightloss, fever, arthralgia, myalgia

ROS: skin, MSK, renal, neuropsychiatric, hemotologic,

Less common signs and sx:
Malar rash, new onset raynaud phenomenon, mouth sores, photosensitivity, pleuritic chest pain

Question 17

Typical signs and sx for SLE

Answer 17

discoid "coin shaped' rash
malar rash
Unexplained seizures or psychosis 
photosensitivity 
positive ANA
Non-erosive arthritis involving 2 or more joints
persistent proteinuria 
serositis

Question 18

If you suspect SLE

Answer 18

4 ACR criteria and Check ANA

if ANA positive: get a CBC, Urinalysis, with differential

Question 19

Tx for SLE

Answer 19

• Hydroxychloroquinine reduces arthritis pain associated with SLE
• combination of glucocorticoid plus immunosuppressant is more effective than glucocorticoids alone in preserving renal function

-glucocorticoid and cellcept achieves SLE nephritis

Question 20

SLE

Answer 20

female, black, episodic illness, fatigue, arthralgia, weight loss myalgia, fever without a focal infection

Exam findings:
discoid rash, malar rash, unexplained seizure or psychosis
photosensitivity, ANA, Anti-dSDNA, Anti-SM, anti cardiolipin

Question 21

Psoriasis

Answer 21

inflammatory skin condition
onset between 15-30 years
smoking increases risk of psoriasis and severity
1/3 of psoriasis patients have 1st degree relative with condition
-physiologic stress associated with onset and worsening of condition
direct skin trauma can trigger psoriasis

worsens with HIV

Question 22

Dx of Psoriasis

Answer 22

scaly skin lesions with additional manifestations in the nails and joints. plaque psoriasis is the most common

Question 23

Psoriasis exam

Answer 23

consider a joint exam if you see a rash and pitting of the nails

Question 24

Psoriasis Tx

Answer 24

topical corticosteroids, vitamin D analongs and tazarotene

systemic biologic therapies for moderate to sever psoriasis

TNF inhibitor for psoriatic arthritis

Question 25

Grave's Disease

Answer 25

Chronic Autoimmune thyroid disorder Thyroid stimulating antibodies activate TSH receptors which triggers increased TH synthesis to amplify catacholamine signaling thru increased bAr recptors Risk factors: female, family hx of autoimmune disorder Signs and Sx: palpitations, heat intolerance, diaphoresis, tremor stare, hypermetabolism

Question 26

Tx for Graves Disease

Answer 26

beta blockers, Anti-thyroid medication

Question 27

Hashimoto's Thyroiditis

Answer 27

Chronic Autoimmune thyroid disoder immune cells attack the thyroid to limit its production Present: hypothyroidism with an elevated TPO Ab level risk factors: female, family history of autoimmune disorder signs and sx: fullness in the neck, fatigue, weight gain, thyroiditis, diffuse muscle pain Tx: levothyroxine

Question 28

Dx for Hashimotos

Answer 28

A frank elevation in TPO Ab level | Measure TSH Levels

Question 29

Primary Immunodeficiency in children

Answer 29

antibody, combined b cell and cell, phagocytic, complement disorders - positive family history - infections in multiple anatomic locations - increase frequency and severity of infections with age - recurrent serious infections with common pathogens - serious infections with unusual pathogens

Question 30

Antibody disorders

Answer 30

majority of primary imunodeficiency presentation: unusually severe and recurrent infection with common organisms broadly characterized as absence or presence of B cells if B cells present: are they of normal quantity or quality

Question 31

Agammmaglobulineima

Answer 31

(X linked bruton tyrosine kinase deficiency) -born absent of b cells in peripheral and umbilical blood -tonsils and lymph nodes may be absent All Ig subclasses are decreased with absence of B cell lymphocyte subset analysis

Question 32

Hypogammaglobulinemia

Answer 32

low or deficient levels of any of the Igs or abnormal response of immunoglobulins to vaccinations most reported CVID...in CVID at least 2 subsets of Igs are low persists after 3 months ear, sinus, pulmonary infections GI problems also occur in CVID

Question 33

T cell disorders

Answer 33

t cells are important to normal function of b cell so most t cell deficiency leads to combined T cell and B cell disorder SCID is the the most serious

Question 34

SCID

Answer 34

presents at life threatening infection as an infant T cell disorder diarrhea, failure to thrive, opportunistic infection, sever routine infections in children younger than 3 months

Question 35

Phagocytic Disorder

Answer 35

abnormalities in neutrophils or monocytes usually diagnosed by age 5 characterized by pneumonia, abscesses, supprative adentis, GI infections *first sign is omphalitis in infants Infections related to inability to kill catalase postive organisms including staph aureus, candida invasive fungal infection

Question 36

Complement Disorders

Answer 36

rare in regards to primary immunodeficiency disease disorders involves encapuslated organisms deficiency of C3 is associated with pyogenic infections of strep pneumoniae and H influenzae C5-C9 deficiency is associated with N. Meningitidis

Question 37

How will primary immunodeficiency disease present?

Answer 37

Recurrent ear, sinus, pulmonary infections, diarrhea, failure to thrive 1. positive family history for immunodisease 2. Diagnosis of sepsis treated with IV antibiotics 3. Failure to thrive

Question 38

Recurrent infection in 1 anatomic location

Answer 38

more likely to have anatomic defect than immunodeficiency ...if infection is present in 2 or more sites we should suspect immunodeficiency

Question 39

HIV

Answer 39

acute hiv infection occurs before seroconversion some people are asymptomatic OR: transient symptoms related to high levels of HIV with viral replication *often misdiagnosed with influenza Signs and Sx: mucocutaneous ulcerations, rash, myalgia, arthralgia, anorexia, weight loss, fever, CNS manifestations, fatigue, headache, lymphadenopathy, pharyngitis, GI distress

Question 40

HIV differential

Answer 40

Epstien Barr, Influenza, Strep Pharyngitis, Viral URI, Acute viral hepatitis, drug reaction, secondary syphillius

Question 41

Acute HIV illness

Answer 41

1-4 weeks after transmission presents as mononucleus or influenza like clinically resembles a T cell immunodeficiney disorder

Question 42

Test for HIV

Answer 42

HIV Viral RNA load--11-12 days P24 antigen (core protein in HIV virus)--14-15 days HIV Elisa--3 to 8 weeks