Allergy and Immunology - 2019 Updated! Flashcards
What are clinical findings of acute GVHD?
Within 3 months of transplant
Skin (rash), GI (anorexia, D&V), liver (transaminitis, hyperbili)
Prevent with immunosuppression (cyclosporine, tacrolimus), treat with steroids
What are clinical findings of chronic GVHD?
Occurs more then 3 months post transplant
Skin (malar rash, sica syndrome), MSK (arthritis, joint contractures), lung (bronchiolitis obliterans), liver (cholestasis, bile duct degeneration), eyes (dry eyes, conjunctivitis)
An 18 month old boy has had 3 pneumonias, 2 episodes of OM and now presents with purulent nasal
discharge. On examination he has a tender 1x1.5cm cervical node with overlying redness. His mother
states that he had an episode of varicella a month ago that was fairly typical in course. Which of the
following investigations will most likely lead to the diagnosis:
a. ADA level
b. NBT
c. Immunoglobulins
c. Immunoglobulins
PID: recurrent sinopulmonary infections suspicious for innate issues (complement defect), adaptive immunity (B cell defect).
Ix: B cells: look at immunoglobulins and antibody titres
- complement (C3, C4, CH50)
ALSO, CVID and ataxia-telangiectasia both present with recurrent sinopulmonary infections and low immunoglobulins
- Which allergy can be treated with immunotherapy:
a) food allergy
b) bee sting allergy
c) penicillin allergy
d) atopic dermatitis
e) cholinergic urticarial
b) bee sting allergy
a) food allergy is now also correct (peanuts)
Allergies that respond to immunotherapy:
- seasonal or perennial allergic rhinoconjunctivitis
- asthma triggered by allergen exposures
- insect venom sensitivity
- IVIG can be used in all of the following EXCEPT:
a) immune thrombocytopenic purpura
b) bone marrow transplant
c) nephrotic syndrome
d) Kawasaki disease
e) Guillain-Barré syndrome
c) nephrotic syndrome (you’ll just pee it out)
Can be used in: ITP, bone marrow transplant (patients exposed to measles), KD, Guillain-Barre
- A child has received IVIG in the course of their treatment. How long should you wait before giving
them vaccines to ensure adequate response:
a. 1 mo
b. 3 mo
c. 6 mo
d. 11 mo
d. 11 mo
Varies between 3-11 months depending on product and dose used
- Which is true regarding RAST:
a) It is more sensitive than skin testing (similar)
b) It is affected by corticosteroids
c) false positives occur in children with hyper-IgE states
d) Preferred test for food allergies
Concept: comparison of RAST to skin testing
c. false positives in children with hyper-IgE states
RAST = testing for allergen specific IgE (now more commonly called allergy specific IgE or sIgE test)
some facts: less sensitive than skin testing, not preferred method for food allergies (skin testing is), BUT not affected by corticosteroids or antihistamines, while skin testing is (neither are affected by montelukast)
13mo child with diaper rash and diarrhea with the introduction of new foods over the
past couple months. Which of the following is most consistent with this presentation:
a) arrange for skin testing and RAST
b) it is due to sensitization to cow’s milk protein
c) carbohydrate intolerance is a common cause
d) citrus fruits and tomatoes can cause this via an immune mediated mechanism
c. carbohydrate intolerance is a common cause
- Sucrase-Isomaltase Deficiency- high amongst Canadian natives- when feeding milk and lactose- no symptoms- once exposed to sucrose and starches (juice, fruits,
crackers, other starches) develop diarrhea, diaper rash, FTT, abdominal distensionavoid
sucrose and maltose- Rx sacrosidase (Sucraid) - They might be describing toddler’s diarrhea where high amounts of osmotically active carbohydrates (ie. Juice) lead to diarrhea. This could cause diarrhea, which would lead to diaper rash.
- no role for RAST in diagnosis because this is only good for suspected IgE mediated CMPI
5 year old had a severe reaction to peanut at 1 year of age. He also has asthma. Now, allergist has ordered an IgE level for peanut. Mom is wondering why. What do you tell them?
- The IgE level will determine how allergic to peanuts she is
- She will not have to go off of her daily montelukast
- This test negates the risk of possible anaphylaxis
- This test is more sensitive than skin testing
- it prevents systemic reactions that could result from the skin test
Kid to have RAST for possible peanut allergy: 2 advantages over skin test; 1 disadvantage compared to
skin test.
advantages: ● Better safety ● Results are not influenced by skin disease or medications disadvantages: ● less sensitive
Recurrent meningococcal meningitis. Most common immunodeficiency is:
a. C5 deficiency
Consider complement deficiency if:
o Recurrent angioedema
o Autoimmune disease (SLE, nephritis, HUS, partial lipdystrophy) - C1, C3, C4
o Recurrent pyogenic infections
o Disseminated meningococcal or gonococcal infection - C5-9
o 2 episodes of bacteremia - C2
o Meningitis with uncommon serotype (other than A, B or C)
You suspect a 6 year old of having a T-cell defect. The best screen is:
a. Schick test
b. TB skin test
c. Candida skin test
d. CD4 count
e. gamma-globulin electrophoresis
c. Candida skin test
Screening tests for T cell defect: lymphocyte count, CXR for thymus size, delayed skin tests (candida, tetanus toxoid)
Deficiency of which of the following may lead to anaphylaxis in a patient given IVIG:
a. IgA
b. IgD
c. IgG
d. IgE
e. IgM
a. IgA
44% have antibodies to IgA (which if they are IgE mediated can cause anaphylaxis to blood products including IVIG)
In which condition is the IgE level normal:
a) Wiskott-Aldrich syndrome
b) immune thrombocytopenic purpura
c) selective IgA deficiency
d) Kawasaki disease
e) ascariasis
b) immune thrombocytopenic purpura
What is the expected IgE level in Wiskott-Aldrich?
high
What is the expected IgE level in selective IgA deficiency?
low
What is the expected IgE level in Kawasaki?
high
A 6 year old presents with eczema, decreased platelets and recurrent OM and pneumonias. Increased IgA and IgE. Decreased IgG. Your diagnosis is:
a. Wiskott-Aldrich
b. SCID
c. IgA deficiency
d. atopic dermatitis
e. normal
a. Wiskott-Aldrich
It’s a TIE! (TCP, immunodeficiency, eczema)
- Low T cell percentages
- treat with IVIG, killed vaccines, BMT curative
Mnemonic: IgG&M low, IgA&E high - it’s a tie
3 year old with a history of fevers. Occur every 4 to 12 weeks for 1-4 days. Growing well. Treated for numerous otitis and pharyngitis. a) Viral illnesses b) FMF c) CVID
A) multiple viral infections
A 15-year-old boy has had 5 episodes of documented pneumonia, 3 RML, 1 RLL, and 1 LLL.
What investigation would be most helpful:
a) immunoglobulins with IgG subclasses
b) pulmonary function tests-
c) CT chest
d) TB skin test
e) sputum culture
a) immunoglobulins with IgG subclasses
X-linked agammaglobulinemia versus CVID: first have small or no tonsils and lymph nodes, second have normal tonsils and nodes
What is true about chronic granulomatous disease:
a) all girls with the disease must be 45 XO karyotype
b) suppurative lymphadenopathy is a characteristic feature
c) there are decreased lymphocytes in 90% of cases
d) there are a decreased number of absolute neutrophils
e) rarely present before 5 years of age
b) suppurative lymphadenopathy is a characteristic feature
Normal number of neutrophils but abnormal function (can eat catalase producing bugs but not kill them)
- features include pneumonia, lymphadenitis, abscesses, onset in infancy
- infections with staph, gram negative enterics, candida, aspergillus
- X Linked Recessive or AR
Dx: flow cytometry and genetic testing (used to use nitroblue tetrazolium)
- In chronic granulomatous disease, all of the following features are present EXCEPT:
a) usually present in males
b) leukocytosis
c) lymphadenopathy
d) hepatomegaly
e) hypogammaglobulinemia
e) hypogammaglobulinemia - no, can have hypergammaglobulinemia
A 6mos male has several abscesses (S. aureus) now and in the past. He has also had recurrent
respiratory infections and Serratia UTI. Now has butt abscess. Which diagnosis is most likely?
CGD
Wiskott-Aldrich
CVID
Hypogammoglobinemia
c. CGD
Common bugs of CGD:
- staph aureus most common
- serratia marcescens
- B cepacia
- aspergillus
- candida albicans
- nocardia
- salmonella
- mycobacterium
Which of the following is true in Wiskott-Aldrich Syndrome?
a) autosomal recessive inheritance
b) poor response to protein antigens
c) decreased IgG and IgE
d) increased risk of malignancy
e) leukopenia
d) increased risk of malignancy
Which immune deficiencies are associated with increased risk of leukaemia and lymphoma?
Wiskott-Aldrich, SCID, CVID, X-linked lymphoproliferative syndrome - all are associated with defects in immune surveillance
Which of the following is true of patients with X-linked agammaglobulinemia?
a. respond to protein antigens, but not to polysaccharide ones
b. should not get live vaccines
c. prone to PCP as infants
d. Risk of lymphoma
e. Risk of EBV associated diseases
b. should not get live vaccines
All immunoglobulins are low; they have no circulating B cells
- Which lab abnormality is seen in Ataxia-telangiectasia?
decreased IgA
decreased IgE
increased IgG
a. decreased IgA (selective absence of IgA in 50-80% of patients), IgE and IgG can also be low
18 mo M with knee arthritis, aspirate grew N. meningitidis. This is the same organism that grew in his
CSF when he had meningitis at 10 months. Which of the following tests is most likely to be abnormal in
this child?
a) Immunoglobulins
b) C3,C4, total hemolytic complement
c) Lymphocyte differentiation
b. C3,C4, total hemolytic complement
C3, C4 - assesses number
CH50 - assesses classical pathway function
AH50 - assesses alternate pathway function
- A 4 month old baby presents with eczema, recurrent pneumonias and absent thymus shadow on CXR.
What is the most likely diagnosis?
a) SCID
All SCIDs lack T cells, some also have no B or NK cells
- lack all Ig classes and subclasses
- extreme susceptibility to bacterial, viral and parasitic infections
- DO NOT give live vaccines
- What is true for X linked agammaglobulinemia?
a. respond to protein antigens (no they do not)
b. no live vaccines
c. at risk for PCP (rare)
d. risk of lymphoma, LIP (no lymph tissue)
e. risk of EBV associated diseases (EBV infect B cell thus immune)
b. no live vaccines
Risk for paralytic polio
S. aureus. What finding would confirm your diagnosis?
a. absent radius
b. no LNs/tonsils
c. draining ears
d. hypoplastic patellae
c. draining ears
Wiskott-Aldrich
Patients with hyperIgE syndrome are classically infected with which bacteria:
● Recurrent severe staphylococcal abscesses of skin, lungs, other + elevated serum IgE
10 year old Lebanese girl with recurrent self limited fevers and abdominal pains. Her albumin is low, and her AST and ALT are slightly elevated (ie: 60-80 range). The remainder of investigations are negative (they don’t tell you what those investigations are!). What is the most likely diagnosis? a. Familial Mediterranean Fever b. SLE c. Cyclic Neutropenia
a. Familial Mediterranean Fever (more in keeping w/ abdo pain + fever)
- fever for 1-2 days every 1-2 months + serositis, arthritis, erysipeloid rash (over dorsum of foot)
o ESR, CRP, fibrinogen, serum AA (amyloid A) often increased
What are some diagnostic criteria for SLE?
SOAP BRAIN MD serositis (pleuritis, pericarditis) oral ulcers arthritis photosensitivity blood low (anemia, TCP, leukopenia) renal - protein loss ANA positive Immune markers (dsDNA) positive Neuro (psych, seizures) Malar or discoid rash
You are seeing a 14 month old boy with a history of severe atopic dermatitis and frequent infections.
On his CBC you find that he has a platelet count of 80.
What is the most likely diagnosis?
Wiskott Aldrich Syndrome
- After how many invasive infections would you be concerned about an immunodeficiency?
Nelson’s- 1 o r more systemic (sepsis, meningitis) bacterial infections; 2 or more serious or
documented bacterial infections in 1 year.
b.) List 4 investigations for work-up of a patient with suspected immunodeficiency
- CBC + Diff
- Immunoglobulins
- Vaccine Titres
- Flow cytometry
Note:
- normal ESR rules out chronic bacterial or fungal infection
- normal neuts rules out congenital and acquired neutropenias and leukocyte adhesion defects
- normal lymphs rules out severe T cell defect
- normal platelet size and count rules out Wiskott
6 week old baby with erythema and induration around his umbilical cord which is still firmly attached.
What underlying condition should you be suspicious of?
LAD I – (Leukocyte Adhesion defect type I)
- recurrent bacterial and fungal infections, despite lots of neutrophils
- note: more than 3 weeks is considered delayed separation of umbilical cord,but 10% of normal infants take >3 weeks
- diagnosis: flow cytometry
Name two organ systems and two organisms that are typically affected by granulocyte defects.
Skin (skin & soft tissue infections) and lungs (pneumonia)
Staphylococcus spp, Serratia marcescens , Klebsiella spp, other Gram negative organisms
(Granulocytes are the precursor to neutrophils, eosinophils & basophils)
