ALLERGY/IMMUNOLOGY

Question 1

X linked recessive disorder characterized by impaired NADPH oxidase function.

Answer 1

Chronic Granulomatous Disease

Question 2

Immunodeficiency disorder where you are more likely to see catalase positive organsim infections including nocardia, staph a, serratia, burkholderia, and aspergillus

Answer 2

Chronic Granulomatous disease

Question 3

Why would impaired NADPH oxidase function lead to an immunodefieicny?

Answer 3

NADPH oxidase generates superoxide free radicals in the phagolysome of neutrophils as a part of the oxidative burst. Without this, bacteria and fungi can escape destruction putting pts at risk of recurrent bacterial and fungal infections.

Question 4

Why are those ith chronic granulomatous disease at risk for catalase positive organism infections specifically?

Answer 4

Catalase positive organisms are able to break down hydrogen peroxide which is a free radical which aids in their evasion of breakdown

Question 5

Dyhydrorhodamine 123 test helps diagnose what?

Answer 5

It helps diagnose CGD by measuring oxidative bursts, its flow cytometry assay using rhodamine derviative

Question 6

Cavitary pneumonia in patients with CGD is most likely caused by what organism?

Answer 6

Nocardia

Question 7

How is phagocytic reponse measured?

Answer 7

Using flow cytometry; measuring oxidative bursts, its flow cytometry assay using rhodamine derviative

This aids in the diagnosis of CGD

Question 8

Chronic enteroviral meningoenchephalitis is associated with what primary immunodeficiency?

Answer 8

X linked agammaglobulinemia

Question 9

BTK gene mutation resulting in defective BRUTON tyrosine kinase leading to impaired B-cell maturation and immunoglobbulin production

Answer 9

X linked agammaglobulinemia

Question 10

Recurrent sinopulmonary infections and gastrointestinal infections

Answer 10

X linked agammaglobulinemia

Question 11

Underdeveloped tonsils/small lympoid tissue

Answer 11

Severe Combined Immunodef
x linked aggamglobulinemia

Question 12

How are immunoglobulins impacted in x linked agammaglobulinemia?

Answer 12

All levels decreased

Question 13

Low IgG and normal antibody response to vaccines is characteristic of….

Answer 13

Transient hypogammaglobulinemia of infancy

Question 14

When do patients with THI (Transient hypogammaglobulinemia of infancy) start IgG synthesis?

Answer 14

After 6 months

Question 15

What kind of recurrent infections do you see in patients with Transient hypogammaglobulinemia of infancy?

Answer 15

Recurrent otitis media, respiratory infections, can be associated with asthma, eczema, and food allergies

Question 16

How can you differentiate common variable immunodeficiency from Transient hypogammaglobulinemia of infancy?

Answer 16

Transient hypogammaglobulinemia of infancy has a normal antibody response to vaccines

Question 17

How can you tell the difference between Transient hypogammaglobulinemia of infancy and wiskott-aldrich?

Answer 17

Wiskott aldrich has microthrombocytopenia

Question 18

What is the figure depicting?

Answer 18

The physiologic nadir in infants which normally occurs ages 3-6 months. This nadir occurs after 6 months in infants with

Question 19

​​​​​​​Patients with _______________________are susceptible to cavitary pneumonia caused by Nocardia due to impaired respiratory burst and defective intracellular killing by neutrophils

Answer 19

chronic granulomatous disease (CGD)

Question 20

Absence of interferon gamma receptors would lead to increased susceptibility to

Answer 20

mycobacterial infection and disseminated disease

Question 21

Decreased levels of immunoglobulins is characteristic of….

Answer 21

B and T cell disorders including x linked aggamaglobulinemia, common variable immunodef, Digeorge, severe combined, wiskott aldrich, ataxia telangiectasia etc

Question 22

Impaired neutrophil oxidative burst is characteristic of

Answer 22

chronic granulomatous disease

Question 23

Isolated deficiency of IgA is characteristic of

Answer 23

selective IgA deficiency

Question 24

Reduced number of peripheral neutrophils is characteristic of

Answer 24

cyclic neutropenia

Question 25

What do we use CH50 assays for?

Answer 25

determine total complement concentration

Question 26

22q11.2

Answer 26

digeorge

Question 27

Markedly low CD19+ B lymphocytes on flow cytometry

Answer 27

X linked aggamaglobluinemia

Question 28

_____________________________should be suspected in a patient with recurrent episodes of edema (eg, face, limbs, bowel, larynx), particularly with a positive family history. Low C4 on complement testing is consistent with the diagnosis.

Answer 28

Hereditary angioedema (C1 inhibitor deficiency) should be suspected in a patient with recurrent episodes of edema (eg, face, limbs, bowel, larynx), particularly with a positive family history. Low C4 on complement testing is consistent with the diagnosis.

Question 29

autosomal dominant mutation leading to deficiency or dysfunction of C1 inhibitor which normally down regulates bradykinin production

Answer 29

Hereditary angioedema

Question 30

What leads to low C4 levels in hereditary angioedema?

Answer 30

Diagnosis of hereditary angioedema is supported by complement testing showing low C4 levels, which are caused by exaggerated cleavage of C4 by uninhibited C1 complex. Low levels of C1 inhibitor protein or C1 inhibitor function confirm the diagnosis.

Question 31

How does hyper IgM lead to low IgG, igA, and IgE

Answer 31

Hyper-IgM syndrome is an X-linked recessive defect in the CD40 ligand, which is normally present on T cells and binds to CD40 on B cells. This interaction induces immunoglobulin class switching, in which immature B cells that normally express only IgM isotypes can produce other isotypes (ie, IgG, IgA, IgE). Deficiency of CD40 ligand in hyper-IgM syndrome prevents class switching, leading to elevated IgM levels and a deficiency of all other immunoglobulin types. Although they are dysfunctional, B- and T-cell concentrations are normal. Lymphocytosis can occur during active infection, and neutropenia, as seen in this patient, is common.

Question 31

How does Bcell count differ in common variable immunodefificney and x-linked agammaglobulinemia?

Answer 31

Question 32

Increased risk for giardia

Answer 32

common variable and x linked agammaglobulinemia

Question 33

_________________presents with recurrent, nonpurulent skin and mucosal bacterial infections, as well as severe periodontal disease. Marked leukocytosis with a neutrophil predominance is common.

Answer 33

Leukocyte adhesion deficiency

Question 34

_________________________ is usually triggered by antibiotic therapy (eg, penicillin, sulfa drugs). It typically occurs in children 5-14 days after medication initiation and presents with low-grade fever, urticarial rash, and arthralgia. Manifestations resolve completely as the medication is metabolized over days.

Answer 34

Serum sickness–like reaction is usually triggered by antibiotic therapy (eg, penicillin, sulfa drugs). It typically occurs in children 5-14 days after medication initiation and presents with low-grade fever, urticarial rash, and arthralgia. Manifestations resolve completely as the medication is metabolized over days.

Question 35

Most common immunodeficiency

Answer 35

Selective IgA deficiency

Question 36

Recurrent sinopulmonary & gastrointestinal infections
Associated with autoimmune disease (eg, celiac, sle) & atopy (eg, asthma, eczema)
Anaphylaxis during transfusions

Answer 36

Selective IgA deficiency

Question 37

_______________________ is a primary immunodeficiency characterized by severe atopic dermatitis and recurrent infections (eg, sinopulmonary, noninflammatory abscesses). Eosinophilia is classic, and the white blood cell count is generally normal despite infection.

Answer 37

Hyper-IgE syndrome

Question 38

Elevated IgE, eosinophilia, normal WBC count, chronic eczema, recurrent abscesses

Answer 38

hyper igE

Question 39

What infection characteristics help differentiate B vs T cell disorders?

Answer 39

B-cell defects typically present with sinopulmonary infections after age 4-6 months, whereas T-cell defects present with opportunistic infections (eg, Pneumocystis jirovecii) and failure to thrive in early infancy. Ataxia-telangiectasia is an example of a combined B- and T-cell immunodeficiency, and cerebellar ataxia and oculocutaneous telangiectasias are classic findings.

Question 40

Periodic episodes of infections following ~21 day cycle. Classic presentation includes fever, malaise, oral ulcers. Some may develop paryngitis, chronic periodontal disease.

Answer 40

Cyclic neurtropenia

Question 41

Mutations in the lysosocmal trafficking reulator gene LYST predisposing patients to frequent bacterial infections, oculocutaneous albinism, peripheral neuropathy, and progressive neurologic dysfunction.

Answer 41

Chediak-Higashi

Question 42

A hereditary form of aplastic anemia caused by an autosomal recessive defect in interstrand cross-link repair (e.g., by homologous end joining). Associated with short stature, café-au-lait spots, thumb and forearm malformations, and an increased incidence of acute myeloid leukemia and myelodysplastic syndromes.

Answer 42

Fanconi Anemia