Specific Diagnosis Modalities Flashcards
name 6 important mediators involved in early phase IgE-mediated reaction
- histamine
- tryptase
- chymase
- carboxypeptidase
- substance P
- calcitonin gene-related peptide (CGRP)
testing for which allergens may come back positive in patients with shellfish allergy? (2)
DM and cockroach (tropomyosin)
what is the highest concentration of venom intradermal skin tests?
1 mcg/mL
what constitutes a significant bronchodilator response in adults?
increase in FEV1 >12% and ≥200
what are some factors that increase FeNO (7)
- asthma
- atopy
- URIs
- age >12yo
- COPD exacerbation
- nonasthmatic eosinophilic bronchitis
- arginine or nitrite/nitrate rich foods
factors that decrease FeNO (8)
- bronchiectasis
- tobacco smoke
- drugs (steroids, anti-leukotriene agents, oxymetazoline, NOS inhibitors)
- exercise
- moderate altitude
- hypothermia
- alcohol
- caffeine
is DLCO reduced in asthma?
No (usually high)
name some allergic diseases with an elevated total IgE (5)
- ABPA
- AFRS
- eczema
- allergic rhinitis
- EGPA
what can a negative DTH (delayed type hypersensitivity) test mean? (2)
- lack of exposure to the tested antigen
- anergy as a result of either primary or secondary cellular immunodeficiency
which organs have the highest concentrations of IgE-producing plasma cells? (2)
tonsils and adenoids
which part of the back has greater skin reactivity for skin testing?
upper back
what conditions can cause a false positive airway hyperresponsiveness? (7)
- allergic rhinitis
- COPD
- congestive heart failure
- cystic fibrosis
- siblings of asthmatics
- URI
- smoking
what is the name given to multiple clumps of sloughed surface epithelial cells that may be seen in asthmatics?
Creola bodies
in which condition is there a lack of dynein arms and loss of ciliary spikes?
PCD (loss of synchronized ciliary movt)
how long does omalizumab-related suppression of SPT last?
4 weeks to 6 months
in allergy skin testing, what causes wheal and flare?
Wheal: histamine -> smooth muscle contraction -> increased vascular permeability
Flare: inflammatory mediators -> vasodilation
What is normal FEF50/FIF50? what is its significance?
- normal is <1
- FEF50/FIF50 >1 indicates extrathoracic obstruction
what is the half-life of free IgE in the serum?
about 2 days
what is the gold standard for the diagnosis of occupational rhinitis?
Direct nasal challenge
which serum protein fraction is elevated in multiple myeloma?
gamma
which complement deficiencies would result in low CH50 and AH50?
C3, 5, 6, 7, 8, 9
which test can be used to detect both excess antibody and excess antigen?
ELISA
what antibody is most associated with renal disease in SLE?
anti-dsDNA
plasmapheresis is indicated as treatment for the immunologic neuropathy associated with which antibody?
Anti-ganglioside antibody (Guillain Barre)
which immunoglobulins do not activate classical complement?
IgA, IgE, IgG4
what complement factors will inhibit the formation of immune complexes?
Factor H or I
what type of immune complexes are formed at the zone of equivalence?
single antibody binds to two antigens, forming large insoluble lattices (ie, can increase turbidity of solution, appear as precipitin lines)
what is zone of antibody excess?
complexes exist as single antibody to single antigen
to what RBC cell surface receptor does the opsonin C3b on immune complexes bind for transport to the liver?
C3b binds to CR1 (aka CD35 or C3b receptor) on RBC
what cell surface marker is present on activated, degranulating basophils?
CD63
what leukotrienes are measured by ELISA?
LTC4, LTD4, LTE4
How is tryptase measured?
fluoroenzyme immunoassay (FEIA)
what to forward scatter and side scatter measure in flow cytometry?
Forward scatter: size
Side scatter: granularity and complexity
what cell surface molecules are absent, as evidenced on flow cytometry, in a patient with X linked agammaglobulinemia? (2)
CD19 and 20
what is the most common method used for quantifying IgG, IgA, IgM and inflammatory markers?
Nephelometry (scattered light to determine turbidity)
what testing method can be used to confirm monoclonal gammopathy and determine heavy or light-chain class type?
immunofixation electrophoresis
what testing method is used for component resolved diagnostics (ie, food component testing)?
microarray (chip technology)
which autoAb are associated with neonatal lupus?
anti-SSA (Ro) and Anti-SSB (La) – also present in Sjogren’s
Which autoAb is associated with eosinophilic granulomatosis with polyangiitis (EGPA or Churg-Strauss)?
p-ANCA (MPO)
what is the name for abnormal bipyramidal crystals of eosinophil lysophospholipase and metachromatic cells found in sputum of patients with asthma?
Charcot-Leyden crystals
which gene demonstrates increased expression in asthmatics and is upregulated in neutrophilic and eosinophilic asthma phenotypes in mouse models?
the mucin gene (MUC5AC)
which airway epithelial cells secrete mucus in response to environmental stimuli?
Goblet cells
which disease results in accumulation of abnormal mucus despite normal ciliary clearance?
Cystic fibrosis
what cell surface marker differentiates naive from activated or memory T cells?
CD45RA - naive T cells
CD45RO -activated or memory T cells
Which PID is associated with defective CD40 and which is associated with defective CD40L?
CD40L - X linked hyper-IgM syndrome type 1
CD40 - AR hyper-IgM syndrome type 3
what naive T cell marker is low or absent in pt with SCID?
CD45RA
what is the CD marker for FcgammaRII?
CD32
what is a characteristic cell surface marker of memory B cells?
CD27
what is the CD marker for CD40L expressed on T cells?
CD154
what CD marker differentiates NK cells from NKT cells?
CD3 is present on NKT cells, but not on NK cells
which complement receptor is also known as CD11c/CD18?
CR4
what cell surface marker is deficient in paroxysmal nocturnal hemoglobinuria?
CD55 or decay accelerating factor (DAF)
what cell surface marker leading to apoptosis is defective in ALPS?
CD95 or Fas
EBV and HHV-6 bind to what cell surface marker?
CD21 (aka CR2 or C3d)
what cell surface marker does rhinovirus bind to? Adenovirus?
Rhinovirus - CD54
Adenovirus - CD46
what defect is associated with leukocyte adhesion deficiency (LAD) type 1?
Defect in common beta chain in CD18
what defect is associated with LAD type 2?
fucosylation defects, leading to sLEX ligand (CD15a) defect
mature tryptase levels are elevated in what condition?
mature tryptase is elevated in anaphylaxis, but NOT in systemic mastocytosis
which immunoglobulins have the highest avidity for C1q and complement activation?
IgM > IgG3 > IgG1 > IgG2
what are the uses of intracellular flow cytometry?
assess cellular function
- neutrophil oxidative burst
- phosphorylation
- calcium reflux
- cytokine production
Tregs display which cell surface markers?
CD3+ CD25+ FoxP3+
CD41+ CD61+ surface markers would be found on which cell population?
platelets
which CD marker is elevated in HLH?
CD25
CD45 is defective in which form of SCID
T-B+NK- SCID
what is the function of CLA-1 on T cells?
mediates homing to skin
which mitogens stimulate T cells? (3)
pokeweed, phytohemagglutinin, concanavalin A
which mitogens stimulate B cells? (4)
pokeweed, lipopolysaccharide, staph aureus and Cowan
what are flow cytometry findings in ADA deficiency?
low CD19, CD3 and CD56
which antigen recognized by B cells is T cell independent?
pneumococcal antigen
which PID has recurrent pyogenic infections without abscess formation?
LAD
Giant azurophilic lysosomal granules in granulated cells are characteristic of which PID?
Chediak Higashi
which screening test can distinguish among X linked, autosomal and X linked carrier forms of CGD?
Dihydrorhodamine 123 test
what is the main reactive nitrogen intermediate produced by macrophages?
nitric oxide
which test for CGD diagnosis is mostly a qualitative measurement of NADPH oxidase activity? which test is mostly quantitative?
NBT is mostly qualitative.
DHR is quantitative
does type III hypersensitivity occur with antigen or antibody excess?
Ag excess.
- results in small immune complexes that do NOT fix complement and are NOT cleared from circulation, leading to deposition in glomeruli, vessels, and joints
which complement factors are evaluated by CH50?
C1-9.
- does not assess for Factor B, D or properdin
what is the C1q binding assay useful for measuring?
circulating immune complexes
Which complement deficiency will have a normal AH50 and low CH50?
C4
Which complement deficiency will 90% of patients develop SLE?
C1q/r/s deficiency
the suffix -ximab refers to which type of mab?
chimeric mab
which monoclonal antibody decreases high-affinity IgE receptors on basophils?
Omalizumab
Hybridomas are created by combining which cells?
Immunized mice and myeloma cells lacking HGPRT
How does PCR work?
it is an enzyme-driven technique that uses oligonucleotide primers to rapidly amplify short regions of DNA in vitro
what is a TREC
T cell receptor excision circles are extra chromosomal DNA byproducts, created during T cell receptor rearrangement during development
what diseases can be screened from a TREC assay? (3)
SCID
22q11 deletion
Trisomy 21
what is the mechanism of action of benralizumab?
binds to IL-5R and induce ADCC (antibody dependent cell mediated cytotoxicity)
what is the target for dupilumab and what cytokines does it inhibit?
targets IL-4Ralpha
IL-4 and 13
what is the difference between dim and bright CD56 cells?
CD56dim - mature NK cells
CD56bright - immature NK cells
a mutation in LYST (lysosomal trafficking protein) can result in which PIDD?
Chediak Higashi
The presence of C1 inhibitor autoantibody can be found in which disease?
Acquired angioedema
What disorder of chemotaxis results in Pectum carinatum, skeletal dysostosis, pancreatic insufficiency?
Shwachman-Diamond syndrome
the presence of C1q autoantibody can be found in which disease?
hypocomplementemic urticarial vasculitis syndrome
what gene defect results in cNKD (classical NK cell deficiency) that is autosomal dominant?
GATA2
what is the preferred laboratory method for evaluating NK cell cytotoxicity?
Chromium release assay
is whole exome sequencing performed using the Sanger method or next-generation sequencing?
next-generation sequencing
what do each of southern, northern and western blotting techniques detect?
Southern - DNA sequences
Northern - RNA seq
Western - protein expression
what are some diseases that can be detected by FISH (6)
Prader-Willi, Angelman, 22q11.2 deletion, Cri-du-chat, Down synd, acute lymphoblastic leukemia, etc
How is histocompatibility testing performed for a bone marrow transplant with an unrelated donor?
Molecular typing, which includes PCR.
Serologic typing is not considered sufficient for unrelated donors.
What HLA types are considered in histocompatibility matching for transplants? Which allele can be mismatched?
HLA types A, B, C, DRB1, DQB1 are considered.
DQ1 mismatch is considered permissible
what are examples of diseases that can be detected by Western blotting
HIV and Lyme
what can microarrays be used to detect? (4)
- gene expression patterns
- single-nucleotide polymorphisms (SNPs)
- chromosomal abnormalities (ie, T21)
- genotype mutations (ie, ataxia telangiectasia)
Age is an important factor when interpreting food specific serum IgE with which particular food allergies?
Milk, egg
peanut in children b/w 6-12mo with AD and egg allergy
what is the differential diagnosis of hilar lymphadenopathy
sarcoidosis, infection, malignancy, hypersensitivity pneumonitis (silicosis, berylliosis), CHF
Central bronchiectasis is found on CT of chest in which condition?
ABPA
vocal cord dysfunction
fixed upper airway obstruction (tracheal stenosis, goiters)
variable intrathoracic obstruction (ie tracheomalacia)
restrictive pattern
obstructive pattern
significant response to a bronchodilator in adults (2)
increase in FEV1 >12% AND >200mL
dose severity of airway hyperresponsiveness correlate with severity of asthma?
No
Nephelometry determination of serum Igls
Radial Immunodiffusion
Laurell rocket eletroimmunoassay
Ouchterlony’s double-immunodiffusion method
Enzyme linked Immunosorbent assay (ELISA)
autoAb for neonatal lupus (2)
Anti-SSA/RO and anti-SSB/La
autoAb for SLE (3)
ANA, anti-dsDNA, anti-Smith
autoAb for drug induced lupus
anti-histone
autoAb for RA (2)
RF and anti-CCP
autoAb for antiphospholipid syndrome (4)
- lupus anticoagulant
- anticardiolipin IgG/M
- anti-b2GPI
- ANA
autoAb for Sjogren’s syndrome (3)
ANA
anti SSA
anti SSB
autoAb for systemic sclerosis (4)
anticentromere
anti-topoisomerase I
anti RNA polymerase I or III
anti fibrillarin
autoAb for CREST
anti centromere
autoAb for polymyositis/dermatomyositis (4)
ANA
anti-Jo 1
anti signal-recognition particle Ab
anti PM-Scl Ab
autoAb for primary biliary cirrhosis
anti mitochondrial Ab
autoAb for Crohn’s
anti saccharomyces cerevisiae (ASCA)
autoAb for UC
p-ANCA
autoAb for GPA
- c ANCA (p ANCA can be positive)
autoAb for Goodpasture’s syndrome (2)
anti glomerular basement membrane
ANCA
autoAb for EGPA
p ANCA
autoAb for pemphigus vulgaris
anti desmoglein 3
autoAb for pemphigus foliaceous
anti desmoglein 1
autoAb for linear IgA disease
IgA against basement membrane zone
autoAb for pemphigoid (3)
against BMZ - BP 230, 180, and hemidesmosomal Ag
cell surface markers of stem cells (1)
CD34
cell surface markers of WBC
CD45
cell surface markers of granulocytes (2)
CD45+, CD15+
cell surface markers of monocytes (2)
CD45+ CD14+
cell surface markers of T cells (3)
CD45+ CD2+ or CD3+
cell surface markers of Treg (3)
CD3+ CD25+ FoxP3+
cell surface markers of B cells (5)
CD45+ CD19+ CD20+ CD21+ CD81+
cell surface markers of naive mature B cell (3)
CD19+ surface IgM+ sIgD+
cell surface markers of mature B cell (2)
CD19+ CD21+
cell surface markers of memory B cell (2)
CD19+ CD27+
cell surface markers of switched memory B cell (4)
CD19+ CD27+ sIgM- sIgD-
cell surface markers of plasma cell (3)
CD19+ CD27+ CD38+
cell surface markers of NK cells (4)
CD45+ CD2+ CD16+ or CD56+
cell surface markers of NKT cells (3)
Cd45+ CD3+ CD16+ or CD56+
cell surface markers of platelet (2)
CD41+ CD61+
CD3 expression and function (3)
- expressed on T and NKT cells (NOT on B or NK cells)
- required for TCR expression and signal transduction
- defects cause T- B+NK+ SCID
CD21 - other names (2), expression (2), function (4)
- CR2, C3d receptor
- expressed on mature B cells and follicular DC
- binds EBV, HHV8, C3d and Cd23
another name for CD23
FceRII (low affinity IgE receptor)
another name for CD117
c-kit
defect in common beta chain of CD18 leads to
LAD type 1
which cell surface adhesion molecule mediates homing of T cells to skin?
CLA-1
CD80 and CD86 bind to which receptors? (2)
CD28 for costimuation
CTLA-4 for inhibition
PDL1 and 2 bind to which receptors (2)
ICOS for costimuation
PD-1 for inhibition
ICOS binds to which ligands (3)
ICOS-L, PDL1, PDL2 for cositmulation
another name and function for FcgRI
CD64
phagocytosis
another name and function for FcgRIIA
CD32, phagocytosis
another name and function for FcgRIIB
CD32B, feedback inhibition of APCs
another name and function for FcgRIIIA
CD16A, ADCC
another name and function for FcgRIIIB
CD16B, phagocytosis
FceRI location (2), function (2) and its ligand (2)
mast cells, basophils
degranulation, Ag uptake
binds to IgE with high affinity, binding site for Omalizumab
FceRII, another name, location (2), function and its ligand
CD23
B cells, eos
function not well known.
binds to IGE with low affinity
another name for CR2
CD21
CCR3 ligands (6) and its function
CCL5 (RANTES)
CCL7 (MCP-3)
CCL8 (MCP-2)
CCL11 (eotaxin-1)
CCL13 (MCP4)
CCL26 (eotaxin-3)
- implicated in allergic disease
CCR4 ligands (2) and its function
CCL17 (TARC)
CCL22 (MDC)
- T cell trafficking
CCR5 ligands (6) and its function (2)
- CCL3 (MIP1a)
CCL4 (MIP1b)
CCL5 (RANTES)
CCL11 (eotaxin-1)
CCL14 (HHC-1)
CCL16 (HHC-4) - cell trafficking and HIV coreceptor
CCR7 ligands (2) and its function
CCL19, CCL21
naive T cell and DC trafficking to LN
CXCR4 ligand (1) and its function (2)
CXCL12 (SDF-1)
B cell development and HIV coreceptor
CXCR5 ligands (1) and its function
CXCL13 (BCA-1)
Home to B-T junction in LN
XCR1 ligand and its function
XCL1 (lymphotactin)
T and NK cell recruitment
coreceptors for HIV entry in to CD4+ T cells (2)
CCR5 and CXCR4
Top left = IgD-CD27+ switched memory B cells
Top right = IgD+CD27+ unswitched memory B cells
Bottom right = IgD+CD27- naive B cells
Emapalumab target antigen
IFN gamma
Ipilimumab target antigen
CTLA-4
southern blot mechanism and example
- DNA probe to detect specific DNA sequences
- gold standard for detecting T cell clonality in lymphoma/leukemia
northern blot mechanism and example
- DNA probe to detect specific RNA sequences
- used more in research
Western blot mechanism and example
- gel electrophoresis to separate proteins by size and shape
- HIV and Lyme disease
Fluorescent in situ hybridization mechanism
Fluorescence-labeled DNA probes to detect specific DNA sequences
Haller cell
concha bullosa
odoni cell
95% PPV for egg
<2yo: IgE >2 kUa/L. SPT >7mm
>2yo: IgE > 7. SPT >8
95% PPV for milk
<2yo: IgE >5. SPT> 8
>2yo: IgE >15. SPT >8
95% PPV for peanut
IgE >14
95% PPV for fish
IgE >20
75% PPV for soy
IgE >30
75% PPV for wheat
IgE >26
95% PPV for tree nuts
IgE >15
what should be done after a negative DBPCFC for full eval of food allergy?
open food challenge
What is the recommended time interval between doses during an OFC?
20-30 minutes
For spirometry results to be considered reproducible, what is the maximum volume error?
150 mL
What is the most typical change seen on the inspiratory flow loop in vocal cord dysfunction?
Partial truncation of the inspiratory flow loop
Which measurement is best to detect subtle airflow limitations on spirometry?
FEV1
classic findings for ABPA on chest CT (3)
- central bronchiectasis
- transient pulm infiltrates (esp upper lobes)
- “finger-in-glove” mucous impaction
which devices can be used to sample indoor allergens? (2)
- Anderson cascade impactor (sieve impactor)
- Settle plates (sedimentation and gravitational sampling)
deficiency of which erythrocyte-bound receptor results in decreased clearance of immune complexes from circulation?
CR1 (CD35)
- function: phagocytosis, cofactor for cleavage of C3b and C4b, clears immune complexes
Which condition results in the largest immune complex lattice formations?
Zone of Ag/Ab equivalence
Which condition results in the formation of the most pathogenic immune complexes?
Zone of moderate antigen excess
Does Montelukast interfere with SPT interpretation?
No
indication for chromosomal microarray (2)
- initial test for nonspecific phenotype
- complement exome sequencing
strengths and weaknesses of chromosomal microarray (3 each)
- Strengths: detects missing or extra chromosomal material, deletions and duplications
- Weakness: poor detection of point mutations, very small duplications/deletions, translocations or inversions
indication for exome sequencing (2)
- complex phenotypes
- complements chromosomal microarray
Strengths and weaknesses of exome sequencing (2/5)
- Strengths: discovery of novel phenotype-associated genes. results can be reanalyzed in the future
- Weakness: more expensive. higher prob of finding VUSes. only ~2% of human genome. no coverage of noncoding regions, poor detection of large insertions/deletions and copy number variants.
weaknesses of genome sequencing (2)
- most expensive
- higher likelihood of finding VUS.