Immunology Flashcards
What is part of adaptive versus innate immune system?
Innate: immediate rxn
- epithelial barrier
- Phagocyte
- Complement
- NK cells
Adaptive: day 1-7
- Humoral= B lymphocyte + Antibody
- Cell Mediated= T cells
Most common primary immunodeficiency?
IgA deficiency
List as many warning signs known for primary immunodeficiency:
min. 4 AOM in 1 yr
min. 2 sinus in 1 yr
min. 2 mon. of Abx
min. 2 pneumonia in 1yr
**FTT
recurrent deep abscess
persistent thrush
**Need IV Abx to clear bacterial infection
min. 2 invasive infection (including septicaemia)
**Fhx primary immune
**= most predictive
Delayed umbilical detachment, infections recur, leukocytosis. Dx?
Leukocyte adhesion defect
Atopic eczema. Bloody stool. Draining Ears. Dx?
Wiskott-Aldrich Syndrome
Recurrent staph abscess, staph pneumonia, dermatitis.
Hyper-IgE syndrome
Sinopulmonary infection + telangiectasia
Ataxia-telangiectasia
List two dx and type of bug=
- humoral
- cellular/combined
- complement
- phagocytic
Humoral= XLA, CIVD, Hyper IgM
= encapsulated (strep, h. influ)
= recurrent sinopulmonary
Cellular/Combined= SCID, DiGeorge, Hyper IgE
= virus (CMV, EBV), protozoa/fungal, mycobacteria, toxo
= candida
Complement= early or late defect
= Neisseria + encapsulated
= meningitis, septicemia
Phagocytic= CGD, LAD, Shwachman-Diamond, Congenital neutropenia
= Staph + gram (-) bugs
= abscess, cellulitis, osteo
Screening primary immunodeficiency BW?
CBC + diff
(low lymph= cell; low neut= phagocytic)
Humoral #= serum immunoglobulin \+/- IgG subclasses f'n= vaccine response
Cellular #= flow cytometry f'n= T cell proliferation study f'n= TST test, candida test
Phagocytic testing
= DHR or NBT
Complement #= C3, C4 f'n= CH50, AH50
recurrent meningococcemia meningitis. Likely immunodeficiency?
C5 deficiency.
How can you tell C3 versus C5 deficiency?
C3/ C4/ C1= AI like
C5-9= Meningococcal, invasive gonococcal
How do you screen for T cell defect.
#
- = CBC w/ diff (lymph)
- = Flow cytometry (CD…)
Function
*= T cell proliferation (response to mitogen)
*= Delayed hypersensitivity (need prior exposure; candida or TST)
= ADA or PNP level
= Thymic Bx
Deficiency in which can lead to anaphylaxis in pt with IVIG:
- IgA
- IgD
- IgG
- IgE
- IgM
IgA
Which dx is IgE NORMAL:
a. Wiskott aldrich
b. ITP
c. IgA def
d. KD
e. Ascariasis
ITP= Normal IgE
- High in Ascariasis, KD, Wiskott
- Can be low in IgA def
Eczema, low plt, recurrent pneumonia or AOM. Likely Dx.
Wiskott Aldrich
- X linked
“TIE”= thrombocytopenia + immunodef + eczema
“Wiskott Whiskey”= high EthAnol (IgE and IgA) makes mentation (IgM) go down.
3 y.o. w/ AOM or pharyngitis every 1-3 mo. Likely?
Multiple viral infection
List any traits you know of Familial Mediterranean Fever:
< 10 y.o.
1-3 d
every 1-2 mo.
trigger: exercise, stress, infection
Arab, Armenian, Turkish, Greek, Lebanese.
Fever
+ serositis (peritonitis, pleuritic, pericarditis)
+ pain (abdo, arthritis, chest)
Tx: Colchicine.
Complication: RF
15 y.o. M has 5 episodes of pneumonia. In different areas. Most helpful:
a. immunoglobulin w/ IgG subclasses
b. PFT
c. CT chest
d. TB skin test
e. sputum Cx
Immunoglobulin w/ IgG subclasses
Nelson: min. 2 resp bac/1 yr min. 1 invasive bac unusual site (brain, liver) unusual severity \+/- chronic oral candidiasis, FTT, infection after live vaccine etc.
What is true about chronic granulomatous disease:
- all F must be 45XO
- suppurative lymphadenopathy key feature
- low lymph in most
- low # of neut
- rarely < 5 y.o. ppt
Suppurative Lymphadenopathy KEY.
- X linked or AR
- most ppt as infant
- # of neut fine= function is issue (can’t kill so wall off = abscess)
- dx: flow cytometry to measure oxidant
- dx: nitroblue tetrazolium dye
- cure= transplant
In chronic granulomatous dx, all (+) BUT:
- male
- leukocytosis
- lymphadenopathy
- hepatomegaly
- hypogammaglobulinemia
Hypogammaglobulinemia
- 2/3 male
- yes lymph + big liver
- yes WBC up
What are the most common bugs for chronic granulomatous dx?
*S. aureus
*Serratia Marcescens.
B cepacia
Which is true of Wiskott Aldrich?
- AR
- Poor response to protein antigen
- CA risk
- low IgE
- leukopenia
Cellular/Combined
Immunodeficiency + Thrombocytopenia + Eczema
X linked
Poor response to polysacc antigen
IG…..EthAnol high= Mentation Low.
Lymphopenia
Poor response to polysacc vaccine.
YES- EBV associated CA, leukaemia, lymphoma
T or F: you can get paralysis w/ administration of live polio vaccine in X linked agammaglobulinemia?
True.
*Avoid live vaccine in X-linked-agamma
No lymph
No B cell
= no antibody
Which lab abnormality is seen in Ataxia-Telangiectasia?
- low IgA
- low IgE
- IgG up
Low IgA
A for Ataxia.
PID: extensive mucutaneous candida..
T cell issue
SCID, Digeorge, WAS, hyperIgE
PID: meningitis, septicemia
Complement issue
Skin abscess, lymphadenitis, osteo
Phagocytic
CGD, LAD, Shwachman-Diamond
Recurrent Sinopulmonary only
Humoral
XLA, CVID
Post polio paralysis. Which PID?
XLA
Post bCG or varicella vaccine dissemination. Or hypo-Ca tetany infant. Which PID category?
Cellular/Combined
SCID, DiGeorge, WAS, hyper IgE
Which PID category is linked with lots of AI conditions?
Complement and Common Variable Immunodeficiency
18 mon. with arthritis, meningitidis, CSF meningitis. Which test?
#: C3, C4 Function: CH50, AH50
What are key Severe combined immunodeficiency (SCID) features?
Lack all Ig classes
Lack T + B + NK
CC: recurrent diarrhea, AOM, sepsis
Lack thymic XR (XLA only other one with no lymphoid tissue)
Opportunistic infection.
Live vaccine= ER
How is SCID tested for on the newborn screen?
No TREC
TREC clip off to make T cell in thymus. If no T cell= No TREC.
Tx: transplant
4 mo. Eczema. Recurrent pneumonia. Absent Thymus on XR. Likely?
SCID
Thrombocytopenia. Normal Hgb. Bad eczema. Chronic fingernail Staph infection. What finding confirm dx?
- absent radi
- no LN/tonsil
- Draining ear
- hypoplastic patellae
Draining ear= recurrent AOM common in Wiskott-Aldrich Syn
Immune deficient
+ Low small Plt + Eczema
B/L no radii= TAR.
Recurrent severe staph abscess of skin + lungs. IgE++++
HyperIgE syndrome
Pneumatocele= AD Dermatitis= AR form
What is the hallmark sign of familial Mediterranean fever?
Erysipelas-like erythema (esp over ankle)
1-3 d
Fever
serositis
arthritis or rash
What is the SLE mnemonic?
SOAP BRAIN MD
Serositis (pleurites, pericarditis)
Oral ulcers
Arthritis
Photosensitivity
Blood (all low) Renal (protein) ANA Immunologic (dsDNA) Neuro (psych, sz)
Malar rash
Discoid Rash
List 4 investigations for W/U of pt with suspected immunodeficiency.
1.** CBC + Diff
(low lymph= cell mediated; low neut= phagocytic)
2. **serum immunoglobulin (humoral)
3. **vaccine titre (like tetanus, diphtheria; humoral f’n)
4. **flow cytometry (cellular function)
Other: - Cellular f'n= **Candida test, T cell proliferation test - Phagocytic testing = DHR or NBT - Complement #= C3, C4 f'n= **CH50, AH50
Name two organ systems + two organism typically affected by granulocyte defect:
- Skin + soft tissue
- Lungs (pneumonia)
Bugs:
- Staph aureus
- Serratia marcescens
- Klebsiella and other
List four findings that suggest immunodeficiency:
1 systemic (sepsis, meningitis)
2 or more serious resp (pneumonia, cellulitis) within 1 yr
Unusual site w/ serious infection (liver, brain)
Unusual pathogen (pneumocystis jiroveci, aspergillus, serrait marcescent)
Usual childhood bug but very severe
Multiple AOM + pneumonia. IgG, IgM normal but IgA low. Warn child about?
Selective IgA Deficiency
Warn about possible anaphylaxis to blood products
Warn about association w/ spur like syndrome (that gluten free may or may not help w/)
T or F: IgA deficiency may remit after d/c phenytoin (dilantin).
True.
T or F: IgA may evolve into CVID?
True.
Tips for vaccine hesitate parents:
- Vaccine safety sys rigorous
- vaccine recommendation based on dx epidemiology and evidence of vaccine safety
- Kids exposed to more antigen in daily routine activities compared to routine vac schedule.
3 indications for conjugated quadrivalent vaccine for meningococcus?
Medical RF:
- Asplenia or functional asplenia (i.e. sickle cell)
- Properdin, factor D or complement deficiency
- HIV
Exposure RF:
- Close contact to invasive meningococcal dx.
- Travellers to endemic area (sub-saharan africa, Hajj)
- Lab who work w/ meningococcus.
- Military personnel in close quarters.
Child with ataxia. Most appropriate screening test for immunodeficiency?
Alpha fetoprotein level.
= Ataxia-telangiectasia
T or F: you should delay live vaccine until T cell competence established.
True.
What are the two primary immunodeficiencies that have absent lymphoid tissue (no tonsil, no lymph node)
XLA
SCID
