immuno Flashcards
What is the most common mutation that is involved in SCID?
A mutation that codes for the gamma chain of an IL2 receptor
X linked reccessive
What is another mutation that can cause a SCID? One that effects the maturation and proliferation of B and T cells
ADA deficiency
Autosomal recessive
With this deficiency there is an accumulation of adenosine and deoxyadenosine which accumulate as dATP.
this inhibits ribonucleotide reductase and impairs DNA synthesis in B and T cells
What does a mutation in the RAG gene do and how does it cause a SCID?
Cannot have any VDJ recombination and no new immunoglobulins are made. Immune system is basically absent
What are the symptoms that occur in a SCID?
RECURRENT infections specifically opportunistic infections including candida, nontuberculosis mycobacteria, and pneumocystis jirovecii
Chronic diarrhea and failure to thrive
What are some ways in which SCID can be diagnosed and what will the results show?
Newborn screening tests will show low levels of TRECs
There will be a low lymphocyte count with les than 20% T cells
Absence of thymic shadow on XRAY
Absent germinal centers
Genetic testing
What are the symptoms of ataxia telangiectasia?
Poor coordination and dilated blood vessels: can have telangiectasias in the eyes
Can have recurrent respiratory infections as well
A mutation in the _____ gene is seen in ataxia telangiectasia
ATM; cannot repair DNA
What are the lab findings in ataxia telangiectasia?
Increased alpha fetoprotein
Decreased IgA, IgG and IgE
lymphopenia: low lymphocytes count
increased risk of cancer
What is the major mutation that occurs in Hyper IgM syndrome?
CD40L deficiency which does not allow for class switching
X linked recessive
What are the symptoms that are seen in Hyper IgM syndrome?
Increased opportunistic infections
Recurrent pyogenic infections: sinusitis, pneumonia, otitis
What do the labs show in hyper IgM syndrome?
Drastically decreased IgG, IgA, IgE and high IgM
No germinal centers in lymph nodes
Genetic testing
What is the mutation that occurs in Wiskott Aldrich syndrome?
X linked mutation in the WAS gene
codes for WASp: impaired immune response and more prone to infections
What kind of infections are patients with WAS more at risk for?
Encapsulated
Opportunistic
What are the symptoms that are seen with WAS?
Eczema
Autoimmune hemolytic anemia and purpura can be seen
Thrombocytopenia: easy bleeding and petechiae, bloody diarrhea, nosebleeds
What will the labs show in WAS?
Increased IgA and IgE
Normal or decreased IgG and IgM
What are the symptoms that occur in X linked agammaglobulinemia?
Recurrent bacterial and enteroviral infections AFTER 6 months (when they run out of the mothers Igs from pregnancy)
because decreased B cells and decreased immunoglobulins
What are the common pathogens that affect patients with Bruton agammaglobulinemia?
Encapsulated: strep pneumo, neisseria, klebsiella, H flu, pseudomonas aeruginosa
SINNUSITIS OTITIS MEDIA PNEUMONIA are common
Individuals with X linked agammaglobulinemia must avoid _____ ________ vaccines
Live attenuated vaccines (polio)
What are the physical exam characteristics of some one who has X linked agammaglobulinemia?
Decreased size of lymph nodes and tonsils
Absence of B cells
Decreased levels of all Igs
What is the most common and least serious immunodeficiency?
IgA
Describe selective IgA deficiency
Decreased IgA leading to recurrent respiratory and entero infections but typically are asymptomatic
Can lead to other autoimmune diseases and allergies, rhinitis, asthma
Patients with selective IgA deficiency will be at an increased risk of ________
giardiasis
What are the symptoms that are seen in CVID>
Seen in early adulthood: recurrent infections: bronchiectasis
Increased risks of lymphomas, autoimmune anemia
What will the labs show from a patient with CVID?
Decreased plasma cells and Igs
What are the differences in defects between digeorge syndrome and velocardiofacial syndrome?
DiGeorge usually has thymic, parathyroid, and cardiac defects.
VCF has facial and cardiac defects
What is the mutation that is involved in IL12 receptor deficiency?
IL12RB
If a patient receives a BCG vaccine and becomes symptomatic, what are you thinking?
IL-12 receptor deficiency
increased risk of mycobacterial infections
What will labs show in an IL-12 receptor deficiency?
Decreased IFN-gamma
Autosomal dominant hyperimmunoglobulin E syndrome involves a mutation in _______ which affects the differentiation of Th____ cells
STAT3 which affects the differentiation of Th17 cells
What are the symptoms that are seen in hyper IgE syndrome?
Eczematous rashes
Bacterial lung infections
Recurrent colds
Coarse facies: prominent forehead, flat nose, large tongue
failure to lose baby teeth
osteopenia
What will labs show in a patient with hyper IgE syndrome?
Increased IgE and increased eosinophils
If there is a defect in AIRE gene, what infections will likely occur?
Candida because there is decreased T cell function
skin nail and mucous membrane infections
______ ______ ______ is an autosomal recessive disorder that is a defect in the LFA1 integrin
Leukocyte adhesion deficiency
This causes an issue with leukocyte chemotaxis and migration
What is the cytokine that codes for LFA1
CD18
What are the symptoms of leukocyte adhesion deficiency?
Late separation of the umbilical cord: because decreased phagocytes (longer than a month sometimes- normal is 1-2 weeks)
Absent pus
Dysfunctional neutrophils
recurrent skin and bacterial infection
Which lymphocytic cell line will be present in the blood but NOT at infection sites in a patient with LAD?
Neutrophils and phagocytes
In ______ _______ syndrome, there is a mutation in the LYST gene which codes for lysosomal trafficking
Chediak higashi
What are the symptoms of Chediak Higashi syndrome? (PLAIN pneumonic)
Progressive neurodegeneration
Lymphohistiocytosis
Albinism: decreased melanocytes
Infections (pyogenic)
Neuropathy
What characterizes the accelerated phase of chediak higashi syndrome?
Ly,phohistiocytosis: lymph nodes invade the organs and cause problems: liver, spleen, bone marrow
Chronic granulomatous disease is a defect in _______ oxidase which does not allow for as intense of an immune response
NADPH: decreased ROS and decreased respiratory burst
What is the inheritance patter of CGD?
X linked reccessive: mostly effects males
Which organisms are patients with chronic granulomatous disease the most at risk for?
Catalase positive organisms
What are the symptoms of CGD?
Recurrent pneumonia
Recurrent skin and soft tissue infections
When I say NEGATIVE nitroblue tetrazolium test you say? >
CGD
What kinds of infections are patients that have a C1-C4 complement deficiency most at risk for?
Increased risk of recurrent pyogenic infections
Autoimmune manifestations
What are the infections that patients who have a terminal complement deficiency most at risk for?
Recurrent neisseria infections
Increased risk for meningitis and gonorrhea
