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Flashcards in immunology Deck (29):

IgA deficiency

Second most common after CVID. Often asymptomatic. Increased allergy and eczema incidence, and celiac. Difficulty clearing rota. More sinopulmonary infections.
Icnreased risk of malignancy and autoimmune disease.


IgG deficiency

Look for repeated organ specific infections, especially pyogenic lower resp and sinupulmonary infections from repeated, often encapsulated/polysaccharide bacteria. May present as "asthma". Bronchiectasis. Otitis media. Sinopulmonary.


X-linked Immunodeficiency With Hyper IgM

X Linked disease. Abnormal CD40. Can't make IgA, IgE or igG, with consequent high levels of circulating IgM.
Chronic pneumonias (esp PCP but of all variations), lots of diarrhea (think cryptococcus). Failure to thrive.
Chronic or cyclic neutropenia. Sclerosing cholangitis. Autoimmune disease. Malignancy.


Common Variable ImmunoDeficiency

CVID is the most common deficiency. Affects ability of B cell to mature to plasma cell. IgA, IgG and sometimes IgM is lower. Recurrent infections, unusual organisms like mycoplasma, PCP and giardia.
Granulomatous disease, lymphoid hyperplasia, autoimmune diseae and malignancy risk.


X-linked agammaglobulinemia (Bruton's)

X linked. BTK mutation (needed for B cell maturation-Pre-B cell). Unlike CVID, has no rate of autoimmune disease. Low or absent mature B cells. No IgG, IgA or IgE. Absent/reduced lymphoid tissue.
Lots of in ifections, including skin infections.
Post vaccine polio infection. Fungal and viral infections handled well except enteroviruses.


Severe combined immunodeficiency

SCID is a life-threatening syndrome of recurrent infections, diarrhea, dermatitis, and failure to thrive. Untreated, usually dead by 2.
Pediatric emergency.
Usually lymphopenic (but may just be nonfunctional) and Ig's of all types decreased.


DiGeorge Syndrome is associated with what immune dysfunction?

T cell dysgenesis.


Wiskot Aldrich Syndrome

eczema-thrombocytopenia-immunodeficiency syndrome. X linked. Has bloody diarrhea because of thrombocytopenia.


Hyperimmunoglobulinemia E (Job) Syndrome

High IgE levels. Recurrent mucocutaneous candidiasis, lichenifications, eczema, wheeze. Abnormal facies.


Most common food allergies

egg, milk, soy, tree nuts, peanuts, shellfish, fish.


Prognosis of egg and milk allergies

85% outgrown by age 5.


peanut, tree nuts, fish, and shellfish allergy natureal history

more persistent.


Natureal history of non-IgE food "allergies"

The proctocolitis and enterocolitis resove usualyl in first year of life. Eosinophilic esophagitis is persistent.


Causes of secondary immunodeficiency...

HIV, CMV, starvation, metabolic disease, steroids, radiation and nutrients like zinc, copper, iron, and selenium.


B-lymphocyte defects

• X-linked agammaglobulinemia (Bruton’s)
• Common Variable Immunodeficiency (CVID)
• Selective Ig-A Deficiency
• Transient Hypogammaglobulinemia of Infancy
• Functional Hypogammaglobulinemia
• IgG Subclasses deficiency
• Hyper Ig-M Syndrome


T cell Dysfunction : Clinical Characteristics - organisms

Infections with intracellular microorganisms

Viruses (HSV, VZ, CMV, EBV)

Protozoa (Cryptosporidium, toxoplasma)

Fungal (Candida, P. carinii )
Bacteria, gram negative enteric (T cell)

Bacteria, polysaccharide encapsulated
(B cell)


T Cell Dysfunction: Clinical Characteristics

• Anergy to recall antigens
• Graft versus host disease
• Failure to thrive (especially with
• Increased B-cell malignancies
• Eosinophilia, thrombocytopenia
• Eczema, alopecia


Classification of Food reactions

1) Autoimmune: ie celiac
2) Non-Immune: enzyme defects/deficiencies, drug reactions, food additive reactions, metabolic diseases (PKU, fructose intolerance, galactosemia... etc.)
3) Immune Mediated: IgE mediated (allergies), mixed IgE/non-IgE: eosinophilic esophagitis; non-IgE (enterocolitis, proctocolitis, chronic constipation).


Red flags with fevers

Inconsolable, poor tone, altered LOC, not feeding, Anuria, lethargy, seizure


Prematurity and infections

Increased risk


Good antiobiotics for fever without a source in a baby

Amp and cefotaxime


Vaccine schedule

Antibacterial for first 6 months: DTaP, menC, pneumo, HiB (IPV though).
Influenza at 6 months.
12mo: mmr, vsv,
Grade 5 hep b and hpv.


People at greater risk of opv induced polio disease

B cell immunodefiencies.


Red flags for vaccines

Previous anaphylactic reactions, recent steroids, recent blood transfusion products


People that should really get vaccines

Splenectomy/hyposplenia, elderly, neonates, immunodeficiency, HIV, cops, heart failure,


Types of vaccines

Live attenuated (mmr, vsv, oral typhoid, oral polio, yellow fever, bcg).

Whole inactivated (Salk)

Parts/protein +\_ conjugate


Parts of vaccines

Additives to enhance immunogenicity (aluminum salt)

Preservatives (thimerosal)

Support growth (egg, animal protein)


Education points for vaccines

Very safe, even multiple early in childhood. Most even with active mild disease.

No link to autism.
No safety reason to avoid thimerosal
Risks: common(pain, swelling, irritability, rash, fever); rare (fever, seizure, hypotonia, parotitis); life threat: GBS, allergic,


Vaccine contraindications:

Anaphylactic rxns: prev vaccine, neomycin, streptomycin, egg, gelatin, bakers yeast.
Live vaccines in immunodeficiency or steroids.
Pregnancy, defer till post partum