August 25, 2015 - Introduction to the Immune System Flashcards
Cardinal Signs of Inflammation
- Redness
- Swelling
- Heat
- Pain
Primary Lymphoid Organs
- Bone marrow
- Thymus
Secondary Lymphoid Organs
- Spleen
- Lymph nodes
Feeling “Full” and Spleen Size
With an enlarged spleen (splenomegaly), it may press on the stomache and cause the patient to feel “fuller”.
White Pulp
Contains the B and T cells and is where they encounter antigens. In the marginal zone is the area where macrophages hang out and where B cells mature.
Red Pulp
The area where macrophages remove old and damaged RBCs. This can also be the site of extramedullary hematopoiesis, which is the creation of new RBCs when the bone marrow is overloaded.
This is also the storage site for iron, RBCs, platelets, and plasma cells.
Asplenic and Infections
At increased risk for infections, particularly encapsulated organisms.
Common ones that you should be vaccinated against are…
- Streptococcus pneumonianiae*
- Neisseria meningitidis*
- Hemophilus influenzae*
Leukocyte Adhesion Deficiency
Missing adhesins or integrins so the neutrophils cannot leave the circulation.
This can result in a lack of pus at the sites of infection.
Myeloperoxidase Deficiency
Relatively common.
Almost always asymptomatic. May cause worse fungal infections.
Chronic Granulomatous Disease
Lack the enzymes that are responsible for generating superoxide radicals. Catalase-positive organisms can cause significant infections. H2O2 is not enough to kill these.
~75% is X-linked, ~25% is AR.
Dihydrorhodamine Test (Oxidative Burst)
Used to test for chronic granulomatous disease. Neutrophils are stimulated with a substance that causes activation and then are incubated with dihydrorhodamine dye. If oxidative radicals are generated, it will change colour.
Normally, you will see a movement of the peak.
Complement Deficiency
A patient is unable to create the MAC. This can present with infections in otherwise healthy individuals.
If you see patients with bacteremia, sepsis, or pneumonia that should not typically have it, you may want to consider a complement deficiency.
Perform a CH50/Total Hemolytic Complement test
Complement Deficiency Test
CH50 / Total Hemolytic Complement
C3 and C4 levels
Other proteins