Immunodefficiency Flashcards
Who should be evaluated for immune deficiency?
Two or more invasive bacterial infections is unusual
Persistent or recurrent sinopulmonary infections warrant further evaluation
Unusual etiologic agents or unusual severity of an otherwise common infection may be a ‘red flag’
What is involved with evaluation for immunodeficiency?
history
physical examination
laboratory studies
What types of information should be collected in the history?
growth and development, types and sites of infecction, severity of infections, HIV risks, family history, autoimmune and allergic phenomenon
What should the physical exam entail?
Physical and anatomic barriers Growth and development Tonsils, nodes, liver and spleen Thrush Rash: eczyma, seborrhea, petechiae, others
What are examples of nonimmunologic lines of defense?
skin and mucous membranes
adequate drainage of body fluids
foreign bodies
What are the four limbs of the immune system?
Cellular immunity, humoral immunity, compliment, phagocytes
What is the most prevalent immunodeficiency?
humoral dificiencies
a selective IgA deficiency
What is SCIDs
Severe combined immunodeficiency syndrom
What is the genetics of SCIDs?
X lined recessive
What is the most common form of SCIDs?
IL-2 gamma chain defecct (this is the critical signal transduction part)
Why is the IL-2 gamma chain so important?
Because this gamma chain is shared between many of the cytokins. Therefore there is no T cell activation, and thus no B cell activation
To test for combined immunodeficiency what type of analysis of lymphocyte proliferation do you conduct?
Analyze response to: mitogens (stimulate all the cells), non-self HLA antigens in mized lymphocyte culture, and specific antigens
What is a common treatment for combined immunodeficiency?
most need immediate bone marrow transplant
while waiting there is aggressive treatment with antibiotics, replacement imunoglobulin and often antivirals and antifungals
For humoral immunodeficiency, what is the most common presentation?
Respiratory infection and unusual enteric infection
typically turns into a sever pneumonia
How is humoral deficiency diagnosed?
B cell enumeration (CD19 and CD20)
Quantitative immunoglobulins (IgG (and subclases), IgA, and IgM, pre and post vaccine titers)
