Immunology Flashcards
List 10 warning signs of primary immunodeficiency
4 or more new ear infections in one year
2 or more serious sinus infections in one year
2 or more months on antibiotics with little effect
2 or more pneumonias in one year
Failure of an infant to gain weight or grow normally **
recurrent deep skin or organ abscesses
persistent thrush in mouth or fungal infection on skin
need for IV antibiotics to clear infection *
two or more deep seated infections including septicaemia
a family history of primary immunodeficiency
*** means the top 3 warning signs of PID
what cells are associated with humoral assessment
CD 19
what cells are associated with t cell
CD4 (helper T cells)
CD8 (cytotoxic T cells)
what cells are measurements of adhesion markers
CD11
CD18
Name 2 humoral immune deficiencies
x- linked agammaglobulinemia (XLA)
common variable immune deficiency (CVID)
what mutation is associated with x-linked agammaglobulinemia
BTK
mutation in bruton tyrosine kinase
what is an important clue on physical exam for x-linked agammaglobulinemia
absent lymphoid tissue (no lymph nodes or tonsils)
what types of infections are associated with x-linked agammaglobulinemia
recurrent sinopulmonary infections
encapsulated bacteria (strep pneumonia, h influenza)
enterovirus meningoencephalitis
what are the laboratory findings associated with x-linked agammaglobulinemia
no immunoglobulins
absent B cells (CD19)
no antibodies to vaccines
what is the treatment for x-linked agammaglobulinemia
IVIG- IV monthly or SC weekly
400-600mg/kg IV monthly
Monitor trough IgG levels to maintain above lower limit of normal for age
what investigations need to be done for someone with agammaglobulinemia
CT chest, monitor PFTs- risk of bronchiectasis
genetic testing for BTK mutation
List 6 combined immune deficiencies
SCID Ataxia Telangiectasia DiGeorge Wiskott Aldrich Hyper IgM Cartilage Hair hypoplasia
When does severe combined immunodeficiency present
2-6 months
what is the most common cause of SCID
mutation in common γ chain of IL2 receptor on X chromosome (X-linked SCID)
what are the laboratory features of SCID
lymphopenia Severely reduced T cell numbers B and NK cell numbers can be low, normal or elevated low or absent T cell function absent antibodies to vaccines
what is the treatment for SCID
HSCT gene therapy (ADA deficiency)
what is the triad for wiskott Aldrich syndrome?
thrombocytopenia
eczema
recurrent pyogenic infections
wiskott Aldrich is associated with increased risk of which malignancies
B cell lymphoma
leukaemia
what are the laboratory findings for wiskott aldrich
thrombocyopenia small platelets *high IgA *high IgE variable IgG low IgM can have lymphopenia decreased T cell function poor antibody responses to some vaccines
how do you manage someone with wiskott Aldrich?
IgG replacement
PJP prophylaxis
HSCT
monitor for autoimmunity/malignancy
what types of infections are associated with wiskott aldrich
encapsulated bacteria (Recurrent otitis media, Pneumonia, Skin infections) opportunistic infections- PJP
What is the most appropriate screening test for ataxia telangiectasia?
alpha-fetoprotein
what is the mutation associated with AT
ATM mutation
autosomal recessive
what are the features of AT
- ataxia (cerebellar)
- progressive neurodegeneration
- telangiectasia- age 4-5, prominent on face, conjunctiva and ears
ataxic child with lymphoma= what?
ataxia telangiectasia until proven otherwise
children with AT should avoid what medical treatment
radiation (CT, Xray)
abnormal DNA repair, cells have increased sensitivity to irradiation
what are the laboratory features of AT
increased alphafetoprotein
absent IgA in 80%
Decreased T cell numbers Low or normal IgG Sometimes elevated IgM Decreased T cell function Can have poor antibody responses to some vaccines
what is the treatment for AT
supportive care- HSCT does not tx progressive neurodegeneration
IVIG if necessary
avoid radiation
what should you recommend for the parents of a child with AT
genetic testing
ATM gene carriers have increased risk of breast and gi ca
what does CATCH 22 stand for
C- cardiac
A-abnormal facial features
T- thyme hypopasia
C- cleft palate and midline abnormalities
H- hypocalcemia
22- 22q11 deletion (3rd &4th pharyngeal pouch)
what are the laboratory features associated with DGS
mildly decreased CD4 and CD 8 cells
hypocalcemia
abnormal T cell function
may have abnormal antibody response to some vaccines (uncommon)
what is the inheritance pattern of DGS
autosomal dominant
remember to screen the parents!
list 3 phagocytic deficiencies
- Hyper IgE (Job’s)
- chronic granulomatous disease (CGD)
- leukocyte adhesion defects (LAD)
what is the defect associated with chronic granulomatous disease?
defect in NADPH oxidase
Patients with CGD are susceptible to catalase positive pathogens. List the catalase positive pathogens (6)
S. aureus** Aspergillus** Nocardia Serratia marcescens Burkholderia cepacia Salmonella
** 2 most common
inflammatory bowel disease is associated with what primary immunodeficiency
up to 40% of x linked chronic granulomatous disease
what is the laboratory finding associated with chronic granulomatous disease
normal or elevated neutrophils
abnormal neutrophil oxidate burst index (NOBI)
what is the management of someone with CGD
aggressive treatment of infections prophylaxis: s aureus: TMP/SMX aspergillus: itraconazole HSCT
what is the mutation associated with HyperIgE syndrome
autosomal dominant mutation in STAT 3
what infections are associated with HyperIgE syndrome
Recurrent abscesses in skin, lungs
• “Cold boils” (no pain, heat, or redness)
• Caused by S. aureus
• Can have pneumatoceles
which primary immunodeficiency is associated with delayed shedding of teeth
hyper IgE syndrome
what are the laboratory features associated with Hyper IgE syndrome
very high IgE (>20, 000)
eosinophilia
Normal IgG, IgA, IgM
Can have poor antibody responses to vaccines
what is the management for someone with hyper IgE
treat infections
anti- staphylococcal prophylaxis (TMP/SMX)
what is considered delayed separation of the umbilical cord?
> 4 weeks
which PID is associated with delayed separation of the umbilical cord
Leukocyte adhesion defect
what type of infections are seen with LAD
staph infections in first year of life (dental, gingivitis, intestinal)
what are the laboratory features associated with LAD
neutrophila (can be >100, 000 even without an infection)
absent surface adhesion molecules CD11 and CD18
what is the treatment for LAD
antibiotic treatment
prophylaxis
HSCT
what are the 3 complement pathways?
classical pathway
lectin pathway
alternative pathway
what is the laboratory finding associated with complement deficiency
abnormal CH50
Check alternative pathway (AH50) if CH50 normal &
still suspect complement deficiency
Deficiency of what is seen in patients with recurrent Neisseria meningitidis?
Deficiency of one of the terminal components (C5-9) that compose the MAC predisposes patients to infection with Neisseria meningitidis.
Congenital deficiency of C1-inhibitor results in what?
hereditary angioedema
early complement components (C1, C2, C3, C4, factor I and factor H) have an association with ?
early complement components (C1, C2, C3, C4, factor I and factor H) have an association with autoimmune diseases and infection with encapsulated organisms.
penicillin anaphylaxis is mediated by what?
IgE against a major determinant
Deficiency of what may lead to anaphylaxis in a patient given IVIG:
IgA
what is the test for T cell function
mitogen proliferation studies
antigen proliferation studies
T cell excision circles (TRECs)- Measured in newborn screening for severe combined immunodeficiency
CVID is associated with what malignancies
non- Hodgkins lymphoma GI malignancies (gastric carcinoma)
What are the side effects of IVIG? (9)
Headaches fevers chills Aseptic meningitis Anaphylaxis*- IgA Hemolytic anemia *- patients with high doses more then for immunology Thrombosis Renal complications Risk of transmission of blood borne illness (screen yearly for HepB/C, HIV)
what immunodeficiency is associated with giardia?
CVID
