Hogan-Clinical Primary Immuno Flashcards
50% of immunodeficiencies have to do with what?
B cells; antibody defects
30% of immunodeficiencies have to do with what?
T cells; T cells defects & combined immunodeficiencies
20% of immunodeficiencies have to do with what?
innate immunity–18% phagocytic defects, 2% complement deficiencies
Which immune things are present in a neonate?
WBCs (including phagocytes) parts of complement NK fcn T cell fcn a little IgM
Which immune things take time to develop in a neonate?
B cells & their antibodies (6-24 months away)
If you have a T cell deficiency at birth…what other deficiency will you likely have?
B cell. T cells help out the T cells.
portions of the complement system dependent on antibodies
If you are worried that a neonate has an infection & you want to test immune markers for that…which immunoglobulin do you look for?
IgM b/c the production of this begins shortly before birth. The only one really intact.
What do you do if a baby comes back with IgA levels of 0?
Nothing! So what…baby isn’t making IgA yet.
How long are we passively protected by maternal antibody?
6 mo
T/F Autoimmune & immunodeficiency problems are completely separate & should not be considered potentially linked.
False.
They both have to do with B cells. If a pt is suspected to have immunodeficiency & has a family hx of autoimmune disease-pay attention. Immuno can come before auto or auto before immune.
If you have problems with your innate immunity–what types of infections might you get?
Lymphadenitis, osteomyelitis, pneumonia, and sepsis
If you have problems with phagocytes–what types of infections might you get? Why?
Phagocytes are non-discriminatory. Wide range of possibilities. Both Gram+ and Gram- and yeast/fungal organisms are attacked
When you get infections from organisms that produce catalase…which disorder might you have?
a problem with your neutrophils (a phagocyte)
chronic granulomatous disease
Give some examples of infections you might get with CGD.
Staphylococci aureus (Gram + in clusters)
Pseudomonas aeroginosa (Gram -)
Aspergillus fumigatus (fungal)
Candida (yeast)
Enterbacteriaceae (Klebsiella and Serratia) Gram-
Others: Nocardia (Gram + rod) /Listeria (Gram + rod)
If you have a problem with your attack complex & can’t lyse holes into certain bacterial cell walls (C5-C9 problem)…what are you more susceptible to?
Neisseria
What does absence of C3 cause?
this is at the heart of the complement cascade
makes it difficult to respond to infections
get lots of pyogenic infections–can be confused w/ a phagocyte disorder
T/F To defeat neisseria, you need a fully functional complement system, especially the attack complex.
True.
Why would a doctor be worried about recurrent otitis media?
if it is in a middle schooler or older person–>their eustachian tubes are no longer horizontal & they may have an immunodeficiency. Catch it now before they get pneumonia or something.
What are some frequent organisms that bother people with B cell problems?
Moraxella
Haemophilus influenzae
Streptococcus pneumoniae
**the common things that bother kids
What are some possible infections that people with B cell problems could get, aside from otitis media?
sinopulmonary problems
When you have infections from odd organisms, such as the following: Pnuemocystis carinii-known w/ AIDS Candida: invasive (lung/esophagus) Systemic viral illness (CMV etc.) Mycobacterial infections: systemic What do you think might be the problem?
T cell problems!
What are some important clinical features of T cell deficiencies?
family hx of T cell problems less than 6 mo opportunistic infections no lymph nodes cutaneous lesions increased chance of cancer failure to thrive GvH w/ mother's blood maybe severe fungal or viral infection fatality after BCG vaccine diarrhea hepatosplenomegaly
What are some important clinical characteristics of B cell deficiencies?
family hx of B cell problems or of autoimmune or immunodeficiencies
onset after 6 mo when B cells are being produced
recurrent bacterial infections
allergy or autoimmune disease
vaccine failure
lots of sinopulmonary infections
perhaps a failure to thrive
What are some important clinical characteristics of phagocytic deficiencies?
susceptible to low grade bacteria & fungi
severe infections, including pneumonia & osteomyelitis
skin infections
lymph adenitis
abscesses
delayed separation of the umbilical cord
If you have a C3 complement deficiency…which types of infections will you start to see a lot?
recurrent bacterial infections
If you have an attack complex (C5-C9) complement deficiency…which types of infections will you start to see a lot?
Neisseria infections
What do azurophilic granules in neutrophils indicate?
Chediak Higashi Syndrome
**not picked up by a cytometer–have to look at a slide
What does a bi-lobed nucleus indicate?
specific granule deficiency
If you have neutropenia, what might you consider as potential causes?
congenital absence
autoantibody
cyclic neutropenia
If you have thrombocytopenia & smaller platelets…which disorder will you start to consider?
WAS: Wiskott Aldrich Syndrome
If you have RBC abnormalities…what are 2 disorders that you might anticipate?
autoimmune anemia
g6pd deficiency.
If you see lymphopenia in an infant what might you consider?
SCID!! Yikes.
What is the CH50 for?
a functional assay
if there is a deficiency anywhere in the complement system–>results will be zero.
What is AH50 for?
a functional assay for the alternative pathway
if there is a deficiency somewhere in this–>results will be zero.
IF both the CH50 & AH50 results come back as zero…what do we know?
There is a problem either in C3 or C5-C9. b/c these are the parts of the complement that they share.
What would a low albumin tell you if you also had a low IgG?
It would tell you that perhaps the low IgG is due to a secondary cause, like diarrhea.
If you suspect an immunodeficiency in a child but the immunology workup comes back normal…& there is nasal polyposis…what do you suspect?
cystic fibrosis
**also think about immotile cilia syndrome
What are some protein vaccines?
diphtheria
tetanus
H. Influenza
**kids can deal with these vaccines.
What are some polysaccharide vaccines?
pneumovax–can deal with this vaccine as an adult
How long after a booster vaccine does it take before the pt starts making IgG?
1 mo
If you suspect a T cell disorder…what are some labs that you might order?
HIV
CD3, CD4, CD8, CD19, CD56
If FISH analysis shows a mutation in 22q11 what does that mean?
Di George
