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Flashcards in Allergy/Immunology Deck (59)
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1
Q

Screening tests for B-cells:

A
  • IgG, IgM, IgA levels
  • Vaccine Ab titers (tetanus, H.flu, Diptheria, Pneumococcal)
  • IgG subclass levels
  • B-cell enumeration (CD19 or CD20)
  • Antibody response to vaccines
2
Q

Screening tests for T-cells:

A
  • Lymphocyte count and morphology
  • Thymic size by x-ray (newborns)
  • Delayed skin tests (over age 2)
  • T cell enumeration (CD 3/4/8)
  • PHA and/or antigen
  • Lymphoproliferation
  • HIV testing
3
Q

Screening tests for Phagocytic cells:

A
  • WBC count, morphology
  • IgE level
  • Dihydrorhodamine or NBT test for CGD
  • Chemotaxis assay
4
Q

Screening tests for complement:

A

CH50 level
C3 level, C4 level

  • Specific complement component assay
  • C1 esterase inhibitor activity and level
5
Q

Most immunodeficiencies are ___

A

Secondary

6
Q
  • Lag in Ig synthesis
  • Recurrent bacterial infections at 4-24mos, diarrhea, FTT
  • Food intolerance, eczema, ex-prematurity
  • Igs low but present, Abs variable, B cells present, neutropenia occasional
A

TRANSIENT HYPOGAMMAGLOBULINEMIA OF INFANCY

Rx: watch and wait, continuous ABX, rarely IVIG

7
Q
  • Complete absence of B-cells
  • Onset after age 6mos of pyogenic infections
  • Absent tonsils and lymph nodes
  • Bronchiectasis, enterovirus encephalitis, vaccine-related polio infection
  • Very low Igs (
A

X-linked Agammaglobulinemia (Bruton’s)

Rx: IVIG, ABX, no vaccines

8
Q
  • Low IgG, IgA
  • High IgM
    +/- Neutropenia
  • X-linked
A

Hyper-IgM Syndromes

Rx: IVIG, GCSF, Transplantation

9
Q
  • Onset after age 10
  • URIs, sinusitis, pneumonia, bronchiectasis, diarrhea
  • Autoimmunity, blood disorders, malignancy, granulomata
  • Igs low (
A

Common Variable Immunodeficiency

Rx: IVIG, ABX

10
Q
  • IgA B cells deficient

- 25% asymptomatic, 25% respiratory infections, 25% allergies, 25% autoimmunity

A

Selective IgA Deficiency

Rx: Avoid Ig, ABX, Medic alert badge, vaccines ok

11
Q
  • Recurrent URI, PNA, sinusitis

- IgG subclass deficiency

A

IgG Subclass Deficiencies

Rx: ABX, IVIG-very rare

12
Q
  • Older than age 2
  • Recurrent URI and lung infections, sinusitis, otitis
  • Poor antibody responses to serotypes in pneumovax (<70% ages 6-60)
  • Sometimes transient, sometimes lifelong
A

Impaired Polysaccharide Responsiveness

Rx: continuous ABX, prevnar 13 vaccine, IVIG rarely

13
Q
  • Early skin, respiratory, and GI infections
  • FTT
  • PCP, moniliasis, rashes, malabsorption, chronic cough
  • Absent lymph nodes and tonsils
  • Very low T cells, B and NK cells variable
  • No thymus or TRECs
A

Severe Combined Immunodeficiency (SCID)

  • AR, XL, sporadic, 18 variants
  • Rx: Transplant, gene therapy for XL-SCID
14
Q
  • Eczema
  • Thrombocytopnia
  • Severe infections
  • MICROPLATELETS
  • IgA and IgE high, IgM low, T cell function decreased
A

Wiskott-Aldrich Syndrome
- WASP gene defect

Rx: ABX, splenectomy, BMT

15
Q
  • Progressive ataxia, telangiectasia
  • Sinopulmonary infections
  • Premature aging
  • Cancer
  • Swallowing problems, Slow cognition
  • ELEVATED ALPHA-1-FETOPROTEIN
  • IgA deficiency, variable T-cell defects, chromosome instability
A

Ataxia-telangiectasia

Rx: IVIG, ABX, nothing very effective

16
Q
  • T cell defect with thymic and parathyroid abnormalities
  • Hypcalcemia
  • Cardiac outflow tract defects
  • Variably low T cells and TRECs, occasional SCID phenotype
A

DiGeorge Syndrome

  • Don’t want to give CMV blood
17
Q
  • T cell defect to Candida antigen
A

Mucocutaneous Candidiasis

  • Rx: local and systemic antifungals
18
Q
  • Inability to form reactive O2 with decreased phagocyte killing because of a NADPH oxidase defect
  • Bone, lung abscesses with S. aureus, Serratia and Aspergilla
  • Large spleen, liver, nodes
  • Poor wound healing
  • Abnormal NBT or Dihydrorhodamine reduction
A

Chronic Granulomatous Disease

XL 67%, AR 33%

Rx: ABX, antifungals, BMT

19
Q
  • Soft tissue infections
  • Dermatitis, Peridontitis
  • Delayed detachment of umbilical cord (>20days)
  • Decreased expression of CD11b on granulocytes
A

Leukocyte Adhesion Defect-type 1

Rx: ABX, local GM-CSF, BMT

20
Q
  • Coarse features
  • Staph infections of skin, lungs, bones, cold abscesses, fractures, scoliosis, dental abnormalities
  • STAT-3 defect of TH17 (pro-inflammatory cytokine)
  • IgE levels >2000
A

Hyper-IgE Syndrome (Job/Buckley Syndrome)

Rx: Bactrim, continuous anti-Staph drugs

21
Q
  • Neisserial infections, autoimmunity, and angioneurotic edema
  • Abnormal CH50
A

Complement Defects

22
Q

What is the approximate half life of IgG in the circulation

A

20-30days

23
Q

What is the best test for T cell deficiency

A

CD4 level

24
Q

What test best distinguishes male infants with X-linked agammaglobulinemia from transient hypogammaglobulinemia

A

B cell count

25
Q

What other immunodeficiency must be excluded in selective IgA deficiency?

A

IgG2 deficiency

26
Q

What immunodeficiency has an elevated alpha-1-fetoprotein level?

A

Ataxia telangiectasia

27
Q

What is the most common cause of persistent vomiting in a child with CGD

A

Granuloma

28
Q

What test is used to screen newborns for SCID?

A

TREC

29
Q

What new drugs are available for hereditary angioedema

A

C1 inhibitor, Kallekrein inhibitor

30
Q

What IgG subclass contains most of the polysaccharide antibodies?

A

IgG2

31
Q

What therapeutic monoclonal antibody is used most often by pediatricians?

A

Palivuzumab (Synagis)

32
Q

Two most common viral triggers for asthma

A

RSV and rhinovirus

33
Q
  • Exp wheezing
  • Can speak in sentences
  • > = 70% PEF
  • SpO2 >=95%
  • Pulsus paradoxus <10mm
A

Mild Asthma

34
Q
  • Exp/Insp wheezing
  • Can speak phrases
  • PEF 40-69%
  • SpO2 90-94%
  • Pulsus paradoxus 10-25mm
A

Moderate Asthma

35
Q
  • Insp/Exp wheezing or quiet
  • Can speak only words
  • PEF < 90%
  • Pulsus paradoxus >25mm
A

Severe Asthma

36
Q

Asthma Predictive Index

A

1 Major Criteria: Atopic Dermatitis, Parental Asthma, Sensitization to aeroallergens
2 Minor Criteria: Allergic Rhinitis, Eosinophilia >4%, Wheezing without URI

Positive if 1 major or 2 minor criteria are met

37
Q

Immunotherapy has/has not been shown to be effective in the treatment of asthma and food allergy

A

HAS NOT

38
Q

Early Spring Allergens

A

Trees

39
Q

Late Spring, Early Summer Allergens

A

Grasses

40
Q

Late Summer, Fall Allergens

A

Ragweed

41
Q

Fall, Damp weather Allergens

A

Mold

42
Q

Immunotherapy for Allergic Rhinitis does not work well against these allergens

A

Molds and dog allergens

Very effective against grass, tree, ragweed pollens, dust mites and cat allergens

43
Q

Non-IgE mediated food allergy usually only involves the ______ system

A

GI

44
Q
  • Recurrent otitis media, bronchitis, pneumonia, meningitis, dermatitis, commonly due to S.PNEUMO and H.FLU
  • Most viral infections handled fine except for ENTEROVIRUSES
  • Normal growth and development
  • B cells absent on flow cytometry
  • Marked decrease in all Ig levels
A

X-linked Agammaglobulinemia (Bruton’s)

Rx: monthly IVIG, prophylactic ABX

45
Q
  • Sinopulmonary and GI infections

- Many asymptomatic

A

Selective IgA deficiency

  • Very common
  • IgA s

Rx: treat infections

46
Q
  • Abnormal delay in Ab synthesis
  • Recurrent URIs
  • Self-limited, recover by 18-36mos
  • Decreased quantitative IgG and IgA levels
  • QUALITATIVE IG LEVELS NORMAL
A

Transient hypogammaglobulinemia of infancy

Rx: treat infections +/- prophylactic ABX

47
Q
  • Sinopulmonary infections
  • Variable age of presentation
  • Decreased quantitative Ig’s
  • QUALITATIVE IG’s ABNORMAL
A

Common Variable Immunodeficiency (CVID)

  • do not respond to polysaccharides

Rx: monthly IVIG

48
Q
  • Recurrent, severe pyogenic infections
  • Opportunistic infections, esp P.carinii
  • Decreased IgG and IgA
  • ELEVATED/NL IgM LEVELS
  • Qualitative Ig levels abnormal
A

X-linked Hyper-IgM Syndrome

  • T cell abnormality - prevents Ab switching from IgM to other Ig classes

Rx: monthly IVIG

49
Q
  • Recurrent bacterial and respiratory infections
  • Normal total IgG levels
  • IgG subclass decreased (IgG1, IgG2, IgG3, IgG4)
A

IgG Subclass Deficiency

50
Q
  • THYMIC HYPOPLASIA
  • DYSMORPHIC FACIES
  • Tetany 2/2 hypocalcemia (parathyroid hypoplasia)
  • R-sided aortic arch, conotruncal abnormalities, ASD, VSD
  • Usually mildly decreased T cells
  • Normal Ig levels
A

Digeorge Syndrome

  • FISH for microdeletion on Chr 22
  • T cell function tends to improve with age
51
Q
  • Recurrent CANDIDAL infections of the nails, skin and mucous membranes
  • 1st year of life
  • Impaired Candida specific T cell responses
A

Chronic Mucocutaneous Candidiasis

Rx: antifungals

52
Q
  • Very sick in first few months of life
  • FTT
  • Chronic diarrhea
  • Frequent viral, bacterial, fungal and protozoal infections
  • Opportunistic infections with Candida, P.carinii
  • Fatal if not treated
  • B AND T CELL DYSFUNCTION
  • SEVERELY LYMPHOPENIC (newborn ALC
A

Severe Combined Immunodeficiency (SCID)

Rx: stem cell transplant

53
Q
  • ECZEMA
  • THROMBOCYTOPENIA
  • SMALL, DEFECTIVE PLATELETS
  • Recurrent bacterial and viral infections
  • Normal IgG levels, decreased IgM levels, increased IgA and IgE levels
  • Decreased qualitative antibody responses to polysaccharide antigens
A

Wiskott-Aldrich Syndrome

  • X-linked recessive
  • Increased incidence of malignancy and autoimmune disorders

Rx: BM transplant, splenectomy if excessive bleeding

54
Q
  • Onset by 2yrs of age
  • PROGRESSIVE CEREBELLAR ATAXIA
  • OCULOCUTANEOUS TELANGIECTASIA develop between 3-6 years of age
  • Recurrent bacterial, sinopulmonary infections
  • Variable antibody and cell-mediated immunodeficiency
A

Ataxia Telangiectasia

  • AR d/o
  • High incidence of malignancy
55
Q
  • Recurrent intracellular bacterial and fungal infections with catalase-positive organisms (S.aureus, Aspergillus, S.marcescens, Nocardia sp, and Burkholderia)
  • GRANULOMA and ABSCESS formation
  • Normal T and B cell function
A

Chronic Granulomatous Disease (CGD)

  • X-linked or autosomal recessive disorder
  • Defective production of reactive oxygen intermediates to kill microorganisms by phagocytes
  • NBT positive
  • NO ABN IN NEUTROPHIL COUNT OR CHEMOTAXIS

Rx: treat infections early and aggressively, prophylaxis with TMP/SMX and Antifungals

56
Q
  • Recurrent bacterial and fungal infections
  • Delayed separation of umbilical cord
  • Impaired wound healing
  • Severe PERIDONTAL disease
  • Leukocytosis
A

Leukocyte adhesion deficiency (LAD)

  • AR
  • Impaired WBC chemotaxis

Rx: treat infections agressively and early

57
Q
  • Recurrent infections with pyogenic bacteria
  • HSM
  • Partial occulocutaneous albinism
  • CNS abnormaliteis
  • GIANT CYTOPLASMIC GRANULAR INCLUSIONS in WBC and plts
  • Abnormal neutrophil chemotaxis AND intracellular killing of organisms
A

Chediak-Higashi Syndrome

  • AR
  • High incidence of malignancies

Rx: BM transplant

58
Q
  • EOSINOPHILIA
  • ECZEMA
  • ELEVATED IGE
  • Recurrent staph infections of skin, subcutaneous tissues, lungs, upper airways and bones
  • Coarse facial features
A

Job’s Syndrome (Hyper IgE Syndrome)

Rx: IV antistaphylococal ABX

59
Q
  • Looks like antibody deficiencies
  • Recurrent bacterial infections
  • Check C3, C4, CH50 levels = entire pathway
  • Disseminated Neisseria infections (GC and meningococcus)
A

Late Complement Component Deficiency