Allergy/Immunology-Notes

Question 1

T cell disorders tend to lead to more of ___ infections?

B cell disorders ____ infections?

Answer 1

T cell disorders: increased viral and fungal

B cell disorders: increased bacterial and protozoal

Question 2

What are some B cell immunodeficiencies?

Answer 2

X-linked Bruton agammaglobulinemia
Selective IgA deficiency
Combine Variable Immunodeficiency
X-linked hypogammaglobulinemia
Hyper-IgM syndrome
IgG subclass deficiency

Question 3

What are some important things to know about X-linked Bruton agammaglobulinemia?

Answer 3

decrease in all Igs across the board!
recurrent bacterial and enteroviral infections after 6mo
absent lymph nodes, tonsil

treat with immunoglobulins and antibiotics

Question 4

What are some important things to know about Selective IgA deficiency?

Answer 4

Normal IgG, IgM, but decreased IgA.
airway, GI infections
autoimmune diseases (Celiac)
Atopy
Anaphylaxis to blood products with IgA

Question 5

What are some important things to know about CVID?

Answer 5

decreased levels of all immunoglobulins, but normal B cells.
sorta a plasma cell deficiency
may see giardiasis, malabsorption

Question 6

what are some important things to know about X-linked hypogammaglobulinemia?

Answer 6

decreased immunoglobulins
with GH deficiency
get short stature!!!

Question 7

What’s the deal with Hyper IGM syndrome?

Answer 7

normal B cells
decreased IgG, IgA
lots of IgM!

Question 8

IgG subclass deficiency?

Answer 8

normal B cells

decreased IgG

Question 9

What are some T cell disorders?

Answer 9

thymic aplasia (DiGeorge syndrome)
IL-12 receptor deficiency
Hyper IgE (Job)
chronic mucocutaneous candidiasis

Question 10

What are some important features of thymic aplasia?

Answer 10

22q11. 3rd/4th pharyngeal pouches don’t develop
cardiac: tetrology of fallot, truncus arteriosus
abnormal facies
thymic aplasia
cleft palate
hypoparathyroidism (hypocalcemia)

FISH to detect deletions
thymic graft, maybe bone marrow transplant

Question 11

IL-12 receptor deficiency?

Answer 11

decreased IFNgamma (from decreased TH1 cells)
disseminated mycobacterial and fungal infections

Question 12

Hyper-IgE Job?

Answer 12

coarse facies
staph abscess, recurrent staph cellulitis, retained primary teeth
increased IgE, eczema
cold abscess (no heat, redness, swelling)

Question 13

Features of chronic mucocutaneous candidiasis?

Answer 13

absent T cell response to candida
vaginal candidiasis in children/teens
infections of skin, mucous membranes

Question 14

What are some combined B and T cell disorders?

Answer 14

SCID
Ataxia-telangiectasia
HyperIGM
WAS

Question 15

Important things to know about SCID?

Answer 15

decreased B cells and T cells
caused by adenosine deaminase deficiency
presentation: FTT, chronic diarrhea, opportunistic infections, no thymic shadow, no germinal centers or lymph nodes

treatment: bone marrow transplant

Question 16

Ataxia telangiectasia…important things to know?

Answer 16

ataxia
telangiectasias
IgA deficiency
increased AFP
decreased IgA, IgG, IgE, lymphocytes

treatment: bone marrow transplant

Question 17

Hyper IgM syndrome?

Answer 17

severe pyogenic & opportunistic infections early in life

only IgM is high, everything else is decreased

Question 18

WAS?

Answer 18

Wiskott Aldrich Syndrome
TIE
T: thrombocytopenia, leading to purpura, hematemesis, hematochezia
I: immunodeficiency, recurrent infections
E: eczema

treat with bone marrow transplant, antibiotics, splenectomy

Question 19

What are some phagocyte deficiencies?

Answer 19

LAD-1
Chediak-Higashi
Chronic Granulomatous Disease
MPO deficiency

Question 20

Things to know about LAD-1?

Answer 20

recurrent bacterial, skin, mucosal infections. impaired wound healing. delayed separation of the umbilical cord
increased neutrophils in blood, but not in site of injury.

in IgE/Job, you see increased neutrophils in abscess just without heat etc.

Question 21

Things to know about Chediak Higashi?

Answer 21

lysosomal trafficking problem
recurrent staph or strep infections
partial albinism
progressive neurodegeneration
giant granules in neutrophils

Question 22

Things to know about CGD?

Answer 22

NADPH oxidase deficiency
increased susceptibility to catalase positive organisms (staph, klebsiella, pseudomonas, listeria, aspergillus, candida, E Coli)

tx: bone marrow transplant

Question 23

MPO deficiency?

Answer 23

chronic fungal infections, candidiasis

especially strong presentation if there is diabetes.

Question 24

Recurrent staph and strep abscesses?

Answer 24

Seen in Chediak Higashi (also albinism)
LAD-1 (no neutrophils in abscess)
Job (cold abscesses, primary teeth retained, eczema)
CGD (recurrent staph, klebsiella, pseudomonas)

Question 25

Allergic rhinitis?

Answer 25

nasal blockage, rhinorrhea, sneezing, pruritis
cobblestoning of posterior pharyngeal wall
thick purulent colored mucus

tx:
avoidance
2nd gen antihistamines: loratidine, certirizine, fexofenadine
leukotriene inhibitor (montelukast)
cromylyn
corticosteroids
atropine
desensitization/immunotherapy

Question 26

Allergic conjunctivitis?

Answer 26

can use antihistamines to treat
vernal: bilateral inflammatory in preadolescent males–cobblestoning of the upper tarsal conjunctiva, may need montelukast for tx

Question 27

Atopic dermatitis?

Answer 27

type 1 hypersensitivity

Question 28

Urticaria, hives, angioedema?

Answer 28

mast cell degranulation
type 1 hypersensitivity, IgE dependent if triggered by food, drugs, viruses
IgE independent (complement mediated) if heat/cold, pressure, sun, opiates, antibiotics etc.

antihistamines, TCAs if chronic, systemic corticosteroids if super severe

Question 29

Milk protein allergy?

Question 30

Drug reactions happen how?

Answer 30

prior exposure, form haptens

Question 31

Which has negative Nikolsky sign and target lesions?
TEN
stevens johnson?

Answer 31

Stevens Johnson has neg. Nikolsky and target lesion.

Question 32

What’s the deal with serum sickness?

Answer 32

Type 3 hypersensitivity
urticaria, angioedema, EM, fever, arthritis
non-IgE mediated

Question 33

What’s the deal with Reactive Arthritis?

Answer 33

Reiter’s Syndrome
Can’t see, pee, or climb a tree
conjunctivitis, urethritis, arthritis
several weeks after chlamydia or diarrheal illness
antibodies go to the joint causing inflammation

Question 34

What’s the deal with Lyme Arthritis?

Answer 34

monoarticular diffusely swollen joint with extreme pain
migratory arthralgias
Synovial Fluid: neg. gram stain, translucent, yellow

Tx: doxycycline unless

Question 35

Rheumatic Fever?

Answer 35

1-3 wks post strep pharyngitis
Jones criteria + ASO
Major criteria: polyarthritis, carditis (endo, peri, myo), subcunodules, erythema marginatum (pink rash over trunk), syndenham chorea
Minor criteria: fever, arthalgia, high ESR/CRP, prolonged PR interval

tx: ASA, corticosteroids, benzathine penicillin G

Question 36

Juvenile Idiopathic Arthritis?

Answer 36

Oligoarticular:

Question 37

C1 inhibitor deficiency?

Answer 37

hereditary angioedema

non-inflamm edema of the limbs, face, genitalia, laryngeal edema, intestines-colicky

Question 38

C3 deficiency?

Answer 38

severe pyogenic infection

SLE, GNP

Question 39

C5-C8 deficiency?

Answer 39

recurrent Neisseria infections