18th Page

Question 1

What is the Type I hypersensitivity skin test?

Answer 1

Skin test / Prick test

A. Cutaneous B. Intradermal - more sensitive

Question 2

What indicates a positive reaction in a Type I hypersensitivity skin test?

Answer 2

Formation of a wheal that is 3 mm greater in diameter than the negative control.

Question 3

What is the Radio Immunosorbent Test (RIST)?

Answer 3

A competitive RIA test for Total IgE.

Question 4

What is the Radioallergosorbent Test (RAST)?

Answer 4

A non-competitive RIA test for Specific IgE.

Question 5

Skin and Prick test

Answer 5

Cutaneous and Intradermal (more sensitive)

Question 6

What is the Direct Antiglobulin Test (Coomb’s test) used for?

Answer 6

Test for Hemolytic Disease of the Newborn (HDN)

Hemolytic Transfusion Reactions (HTR), and

Autoimmune Hemolytic Anemia (AIHA).

Question 7

What is the purpose of Direct Fluorescence examination?

Answer 7

To examine renal tissue biopsy for Goodpasture’s syndrome.

Question 8

What does Indirect fluorescence immunoassay detect In Type II?

Answer 8

Autoantibodies.

Question 9

What tests are used for autoantibodies in autoimmune disorders in Type III?

LIF

Answer 9

Latex agglutination
Immunoassays
Fluorescent staining.

Question 10

What is the gold standard test for contact dermatitis (Type IV)?

Answer 10

Patch test.

This test must be done when the patient is free of symptoms or at least has a clear test site.

Question 11

What indicates a positive patch test?

Answer 11

Redness with papule or tiny blister.

Question 12

What is the Mantoux Method/Tuberculin Test/PPD?

Answer 12

A test using 0.1 mL of 5 tuberculin units (TU) of PPD injected intradermally into the forearm.

Question 13

When is an induration considered positive in the Mantoux test?

Answer 13

An induration of 15 mm or more in individuals with no risk factors.

Question 14

What is a positive Mantoux test result in high-risk groups?

Recent immigrants of high prevalence countries
intravenous drug users
employees of heath care
persons with clinical condition
children younger than 5 yrs old

Answer 14

A reaction of 10 mm or greater

Question 15

What indicates a positive result for individuals with HIV or immunosuppression?

or chest x-ray with tuberculosis
recent contact with TB

Answer 15

An induration reaction of 5 mm or more.

Question 16

What does a positive Mantoux test indicate?

Answer 16

Previous exposure to M. tuberculosis or a related organism, but not necessarily an active infection.

Question 17

positive test results in Mantoux method can also occur in:

Answer 17

Persons who have previous BCG (Bacillus Calmette Guerin) vaccine for tuberculosis.

Question 18

It uses M. tuberculosis Ag extract prepared from PPD (purified protein derivative )

Answer 18

Mantoux/tuberculin/PPD test

Question 19

What is Humoral Immunity?

Answer 19

B-cell deficiency.

Question 20

What is Cellular Immunity?

Answer 20

T-cell deficiency.

Question 21

What is a defect of phagocytic function?

Answer 21

It is characterized by the inability of a phagocyte to kill ingested microorganisms due to enzyme deficiency in NADPH oxidase or impaired oxidative/respiratory burst.

Question 22

Humoral Immunity examples

TSCX

Answer 22

Transient hypogammaglobulinemia of infancy
Selective IgA deficiency
Common variable immunodeficiency
X-linked agammaglobulinemia/Bruton’s agammaglobulinemia

Question 23

What is Selective IgA deficiency?

Answer 23

It is the most common immunodeficiency.

Question 24

What is X-linked agammaglobulinemia?

Answer 24

Patients lack circulating mature CD19 positive B cells and exhibit a deficiency of immunoglobulins of all classes.

The underlying genetic mechanism is a deficiency of an enzyme called Bruton’s tyrosine kinase in B-cell progenitor cells.

Question 25

What is DiGeorge syndrome?

Answer 25

It is a developmental abnormality of the third and fourth pharyngeal pouches that affects thymic development.

Question 26

What is Purine Nucleoside Phosphorylase (PNP) Deficiency?

Answer 26

affects an enzyme involved in the metabolism of purines, leading to decreased T cell numbers due to toxic metabolite accumulation called Deoxyguanosine triphosphate

Question 27

Examples Severe combined immunodeficiency (SCID) Wiskott-Aldrich Syndrome What is Ataxia-telangiectasia

Answer 27

Combined deficiency of T and B cells

Question 28

What is Wiskott-Aldrich Syndrome?

Answer 28

It is characterized by a triad of eczema, thrombocytopenia, and immunodeficiency.

Question 29

What is Chronic Granulomatous Disease (CGD)?

Answer 29

Both sex-linked/autosomal recessive are normal but function abnormally It is characterized by a phagocyte's inability to kill ingested microorganisms due to enzyme deficiency (NADPH oxidase) Macrophage-rich granulomas ae in liver, spleen, etc ## Footnote Macrophage-rich granulomas can be found in the liver, spleen, and other organs.

Question 30

What is the Nitroblue Tetrazolium Reduction Test?

Answer 30

It tests the ability of white blood cells to reduce yellow water-soluble tetrazolium to a BLUE insoluble formazan. ## Footnote Normal WBC: able to reduce; CGD: remains yellow, colorless.

Question 31

What is the Flow Cytometry Test?

Answer 31

It uses Dihydrorhodamine to assess the fluorescence of white blood cells when it is reduced ## Footnote Normal WBC: fluorescence when reduced; CGD: no fluorescence.

Question 32

Bruton Tyrosine Kinase (BTK)

Answer 32

enzyme deficiency in B cell progenitor cells Bruton's agammaglobulinemia (X-linked)

Question 33

CGD IN Nitroblue Tetrazolium Reduction Chronic Granulomatous Disease ??

Answer 33

Yellow/Colorless

Question 34

CGD in flow Cytometry Chronic Granulomatous Disease ??

Answer 34

No fluorescence