week 1

Question 1

•Barrett’s esophagus

Answer 1

•In chronic gastric reflux the normal stratified squamos of the the lower esophagus change to intestinal type columnar epithelia that secretes protective mucus

Question 2

Cells swell Why?

Answer 2

–Cells swell bc no ATP available to power NA/K pumpà

Increased Na inside cell à

increases water in cellà

swelling

Question 3

necrosis vs apoptosis

Answer 3

Question 4

coagulative necosis.

Answer 4

ischemia

maintian archtectire but no nucleas

Question 5

Liquefactive necrosis

Answer 5

infection

brain ischemia

• abscess, pancreatitis
• Seen in bacterial or fungal infections when microbes stimulate accumulation of inflammatory cells and the enzymes of leukocytes digest (Liquefy) the tissue •For unknown reasons hypoxic death of brain tissue results in liquefactive necrosis. Brain tissue gets completely digested and liquid is left behind eventually cleared by macrophages •abscess, pancreatitis

Question 6

Caseous necrosis

Answer 6

TB

•Found in foci of tuberculosis infections •Caseous = cheesy •Looks friable, yellow-white •Tissue architecture completely gone unlike coagulative •Area of caseous necrosis is encircled by an inflammatory border •The necrosis and inflamm border = granuloma

Question 7

fat necrosis

Answer 7

•Occurs in areas where there is a lot of fat •Classic examples are acute pancreatitis- pancreas releases lipases due to cell injury and these lipases digest triglycerides of fat cells into free fatty acids • Free Fatty acids and calcium combine to produce white chalky substance = saponifaction •Other area fat necrosis occurs is after trauma to the breast

Question 8

antibody classes

Answer 8

Question 9

MS?

Answer 9

T cells and macrophages attack CNS

Question 10

Thrombocytopenia?

Answer 10

autoantibodies agaisnt platelets

Question 11

guillain barre

Answer 11

autoantibodies against the schwann cells

Question 12

hasimotos thyroiditis

Answer 12

autoantibodies against thyroglobulin

hypothyroidism

Question 13

celiac disease

Answer 13

glutenenteropathy

Question 14

systemic lupus erythematous

Answer 14

autoantibodies against dna histones proteins

nephritis arthritis

Question 15

rheumatoid arthritis

Answer 15

autoantibodies against the joints

Question 16

rheumatic fever

Answer 16

mimicry

autoantibodies to myosin following group a strep infection M protien is close to the myosin. licks joints and bites heart.

Question 17

primary immune is diff from secondary how?

Answer 17

primary is inherited

secondary is aquired

Question 18

chronic granulatomas disease?

Answer 18

NADPH deficiency

it is needed for the respitory burst in neutrophils

without it the neutrophils wont kill the infection and are succeptible to more infections.

nadph is needed for superoxide

Question 19

what kind of organisms are a problem in people with CGD?

Answer 19

infections with catalase positive organisms.

Cause catalase will degrade the H2O2. it is the only toxic material they have around to kill the organism.

Question 20

CGD

test?

Tx?

onset ?

in whom?

Answer 20

•Onset by age 2 •X linked and AR •Pneumonia •Osteomyelitis •Abscesses •Test: DHR •Treatment—Trimethoprim+sulfamethoxazole prophylaxis •Definitive tx= bone marrow transplant

Question 21

Leukocyte Adhesion Defects

signs?

where is defect?

Answer 21

umbilial cord wont fall off

dont form pus

gingivitis

• Defect is in LFA-1/MAC-1 integrin on phagocytes
• Autosomal recessive •Neutrophils cant attach to endothelium and get to site of bacterial invasion •Since neutrophils cant get to endothelium there are increased neutrophil levels =neutrophilia

you keep sending out signal and even though you are sending alot none are getting in and you keep sending out that signal.

Question 22

c2 deficiency

screeening test?

what does it usually associate with?

Answer 22

test: –Screening test is CH50 —tests classical complement pathway

–Most common complement deficiency –Autosomal recessive –Associated with Lupus —1/3 of pts with C2 defect have lupus –Assoc with other vascular problems- vasculitis, dermatomyositis –Screening test is CH50 —tests classical complement pathway –Repeat infections from H. Influenzae, enteric bacteria

Question 23

Late complement deficiencies

Answer 23

•C5-C9 of the complement pathway make the membrane attack complex that makes a whole in the bacteria and kills it. •Main infection if the pt has a C5-C9 deficiency is recurrent infections with Neisseria only. •Neisseria gonorrhea and neisseria meningitis •CH50 is screeing test

Question 24

SCID

Answer 24

• Severe combined immunodefeciency –Severe defects in T and B cells –Onset in infancyà live in a bubble –Infant will have recurrent diarrhea, recurrent otitis media, thrush(candida infection), failure to thrive –Repeat infections with viruses, bacteria, fungi especially Candida, pneumocystis, psuedomonas –100% die without bone marrow transplant –Screening test—CBC will show WBC below 1,500 –Confirmatory test-CBC with differential which will show breakdown of T cell, b cell #s
• Multiple defects at cellular level can cause variety of immune deficiencies that all are referred to as SCID

Question 25

X-linked SCIDs

Answer 25

•Due to mutation in the gene encoding the Gamma chain shared by cytokines IL-2, IL-4, IL-7 plus other •IL-2 receptor gamma chain mutation-normally stimulates growth of helper of helper T cells and Cytotoxic T cells •Without helper T cells, B cells don’t develop normally or if they do they stay immature •Labs will always show very low or absent T cell numbers….Mature B cells will be low as well but immature B cells can be normal or high.

Question 26

autosomal recessive SCID

Answer 26

•AR is 40% •Mutation in adenosine deaminase (ADA) •ADA is needed for purine metabolism and without it adenosine and deoxyadenosine triphosphate metabolites accumulate •This is directly toxic to T and B cells

Question 27

trecs are a marker for? in SCID what is TREC level like?

Answer 27

•TREC’s are nonreplication pieces of circular DNA of naïve T cells generated when a T cell receptor is being made •TREC’s are a marker for normal naïve T cells •The more TREC’s there are, the more recombination of T cell receptors is occuring •In SCID, TREC’s will always be low

Question 28

DiGeorge Syndrome

Answer 28

* Microdeletion in chromosome 22q11.2 •Disorder results from malformation of the 3rd and 4th pharyngeal pouch during embryology •**3-4 pharyngeal pouch** is where the Thymus Parathyroid, aortic arch and parts of face develop from * Malformed parathyroid à low PTH à low calcium à tetany •Thymic hypoplasia –T cells originate from here –Low numbers of T cells –Recurrent VIRAL and FUNGAL infections

Question 29

Digeorge

Answer 29

•Catch 22 •Cardiac defects •Abnormal facies •Thymic hypoplasia •Cleft palate •Hypocalcemia (LOW PTH) •22nd chromosome deletion

Question 30

tetany?

Answer 30

involuntary muscle contractions from a problem with the parathyroid gland.

Question 31

how do you test? digeogre

Answer 31

•Preferred Dx test is chromosome microarray/DNA duplication deletion test •RT-PCR •FISH • •Live vaccines can cause disease in these pts •Absent thymic shadow on CXR

Question 32

XLA

Answer 32

•X-linked recessive •Defect in Btk- a tyrosine kinase gene needed for B cell maturation •B cells make antibodies •Labs will show decreased number of B cells •Decreased number of antibodies of all classes •IgG, IgA, IgM, IgE •Onset in infancy, early childhood B cells dont mature right. •Recurrent bacterial infections starting at about 6 months of age after maternal antibodies fade away •H. influenze, S. pneumonia, mycoplasma pneumoniae

Question 33

CVID

Answer 33

•B cell maturation defect with many causes •Low IgG •AND •Low IgM or IgA or both •Onset in 20’s •Pulmonary disease is common initial presentation •Increase risk of Non hodgkins lymphoma, gastric cancer, autoimmune disease

Question 34

acute vs chronic inflamation?

Answer 34

Question 35

leukocyte migration through blood vessels?

Answer 35

Question 36

granulatomous inflamation? what casues multinucleated giatn cells? seen in what diseases?

Answer 36

Question 37

type 1 hypersensativity? what do you need? how is it mediated what are some causes of it?

Answer 37

1st exposure- Free antigen enters body gets recognized by B-cell B cell produces IgM 7-10 days later there is class switching IgMà IgE IgE binds to mast cells via Fc portion on IgE and Fc receptor on mast cell 2nd exposure Free antigen enters body Antigen binds IgE on mast cells Release of vasoactive amines-histamine, recruitment of Eosinophils, BASOPHILS Itchy, vasodilation, bronchoconstrictionàdeath Examples of type I reaction 1-bee stings 2-peanuts, pine nuts, other nuts 3-seasonal allergies- pollen 2 exposures must occur before anything happens !!! ANAPHYLAXIS/ ASTHMA IMMEDIATE!!!!

Question 38

type 2 hypersensativity. what is it mediated by? what are some examples of it.

Answer 38

* Perceived or true antigen is present inside the body and **attached to a cell or other structure like basement membrane** •Igm or IgG bind to this antigen with the Fab portion of the antibody •The Fc portion of the IgM/IgG is facing away from the cell •Complement factors that are nearby will bind the IgM/IgG Fc portion which triggers complement activationà MAC formation à destruction of cell •AB MEDIATED!!!!! * Type II 1.IgM/IgG can also bind regular cellular receptors that the body thinks are foreign 2.This binding can simply interfere with normal cell function by acting as a competitive antagonist-Example-Myasthenia Gravis, pernicious anemia 3.Or once bound complement is activated and the receptor/cell gets destroyed * Type II Examples •Noncytotoxic-pernicious anemia, grave’s dz, myasthenia gravis, •Cytotoxic-Transfusion reactions, rheumatic fever, goodpasture’s, bullous pemphigoid, pemphigus vulgarisExample-Goodpasture’s syndrome

Question 39

hypersensativity type 3? what causes it? what causes disease in it?

Answer 39

•Complex of three things –Antigen+antibody+complement –Once all three are bound together in the blood they get too heavy and precipitate! –Where they settle is where the disease occurs ## Footnote •Example- “Serum sickness” –occurs when person is given drugs and something in the drug is perceived as foreign. IgMàIgG Antibodies against it are produced and 5-10 days later the Ag+Ab form which activates complement forming the Ag+Ab+complement complexàprecipitates in skin=urticaria, joints=arthralgias

Question 40

what is serum sickness? what type is it found in?

Answer 40

•“Serum sickness” –occurs when person is given drugs and something in the drug is perceived as foreign. IgMàIgG Antibodies against it are produced and 5-10 days later the Ag+Ab form which activates complement forming the Ag+Ab+complement complexàprecipitates in skin=urticaria, joints=arthralgias

Question 41

what diseases are associated with type 3?

Answer 41

•Type III •Lupus- ANA, Anti-dsDNA, anti-Smith antibodies are present that bind with their antigen and stimulate complement. •Precipitates in kidneys, joints skin •Other examples-Rheumatoid arthritis, polyarteritis nodosum, post-streptococcal glomerulonephritis

Question 42

type 4 hyper senasativity. what is the mediator? what is the a halmark of it? what are some examples of it?

Answer 42

* Type IV •Delayed response and does not involve antibodies •Mediated by T CELLS •Antigen enters bodyàengulfed by APC and presented to a T CELL •T CELL is now sensitized so that the next time it encounters antigen it will release cytokines •It takes time 12-48hrs for the primed T CELL to get to site of antigen and release cytokines and cause an effect. •Ex-Tuberculosis skin test-redness,swelling 2-3 days after TB test •Others-Poison Ivy, Type I DM, Multiple sclerosis, Guillan Barre, hasimoto’s thyroiditis * Ex-Tuberculosis skin test-redness,swelling 2-3 days after TB test •Others-Poison Ivy, Type I DM, Multiple sclerosis, Guillan Barre, hasimoto’s thyroiditis

Question 43

## Footnote A 45 year old man has a huge appetite. At a meeting he notices there is a pile of cookies that all contain peanuts which everyone brought because they knew this man wouldn’t be able to eat because he normally takes everyones cookies. The man is starving so he decides to eat the cookies with the peanuts. Within minutes he develops blotchy erythematous, pruritic plaques on his skin. Which of the following sensitized cells release a mediator that produces these skin lesions? A) Mast Cell B)neutrophil C)natural killer cell D) CD4+ lymphocyte E) Plasma cells

Answer 43

## Footnote Answer is A This man has hives related to an allergy to an antigen in the nuts. This causes a type I hypersensitivity rxn, in which IgE antibodies that are already bound to a mast cell from a previous exposure get crosslinked by the peanut antigen and cause degranulation

Question 44

## Footnote • A 32 yo african american women has lupus and has complained of joint aches, muscles aches. Chemistry panel shows an elevated serum urea nitrogen level indicating kidney dysfunction. Kidney biopsy, microscopic exam and staining reveal a granular pattern of antibody-antigen complex bound to complement Cq1. This pattern is most typically produced by which of the following Hypersensitivity rxns •I • II • III • IV

Answer 44

## Footnote * Answer * III-this is immune complex deposition and this women has lupus.

Question 45

## Footnote During the second pregnancy for a 25yr old women an ultra sound at 20 weeks shows hydrops fetalis/increased amniotic fluid. Her first pregnancy was normal. The current pregnancy ends at 31weeks gestation and the baby is shown to have jaundice, scleral icterus and a low hemoglobin. What are this baby’s symptoms due to? 1) receptor antibodies 2) loss of self tolerance 3) immune complex formation 4) Ab mediated cell destruction

Answer 45

## Footnote Answer Ab mediated cell destruction This is Rh incompatibility between the mom and the baby. Maternal antibodies vs a different Rh status in the baby were formed during the birth of the moms first baby and crossed the placenta during the 2nd pregnancy. The antibodies bind the babies rbc’s and destroy them via type II HSN rxn