Immunology 2 - primary immunodeficiencies Flashcards
4 main components of immune defence
B cell and antibodies - humoral specific
T cell - cellular, specific
complement - innate
phagocytes - innate
What causes PID?
single gene defects
PID in Europe
antibody disorders
T cell disorder
phagocyte disorder
complement deficiencies
What are secondary immunodeficiencies?
acquired diseases with all components of immune system present and functioning
PID or SID more common?
secondary
Secondary immunodeficiencies examples
burns, trauma, malnutrition
infection, diabetes, renal failure, asplenia, malignancy
surgery, splenectomy,drugs
Antibody deficiencies
one or more subclass of antibodies eg IgG, IgM absent mature B cells
cellular immunodeficiencies
impaired T cell function or absence of normal T cells
Innate immune disorders
defects in phagocyte function
complement deficiencies
absence or polymorphisms of PRR
features of antibody deficiencies
recurrent bacterial infection of resp tract
H influenzae and strep pneumoniae
features of cellular immunodeficiencies
CMV,PJP
features of defects in phagocyte function
staph aureus - sepsis, skin lesions, abscesses
aspergillus - lungs, bones
complement deficiencies features
N meningitidis
Recognising PID
severe? hospital/IV persistent unusual - organism recurrent FH
Warning signs for PID
ear infection, sinus infection, viral infections, fungal infection recurring diarrhoea chronic pneumonia IV antibiotics FH
other presenting symptoms apart from infection for PID
auto-inflammation
auto-immune
malignancies
Neutrophil defects
congenital neutropenia
leucocyte adhesion defect
recognition and phagocytosis
intracellular killing
neutrophil defect - adhesion
missing CD11/18
What parts of immune system are capable of opsonisation?
complement
antibodies
complement - chemotaxis
C3a,C5a
complement - opsonisation
C3b,C4b
lysis of micro-organism without cell wall - complement
c5b-9
Hereditary angioedema
C1 inhibitor deficiency
autosomal dominant
Hereditary angioedema features
recurrent episodes of non pitting, non pruritic, non erythematous, painless swellings
subcut tissues, intestines, oropharynx
Hereditary angioedema acute emergency
pharyngeal/laryngeal obstruction
acute abdo pain
Treating Hereditary angioedema
C1 inhibitor infusion OR
FFP
Adaptive Cd4 deficiency - fungal infections
Pneumocystitis pneumonia
cryptococcal meningitis
Mutation associated with absent mature B cells
BTK
22q11 deletion syndrome epidemiology
de novo mutations
1 in 4000
22q11 deletion syndrome clinical presentation
congenital cardiac anomalies
palatal defects
learning diabilities
immunodeficiency - Thymus a/hypo plasia
22q11 deletion syndrome facial features
short forehead protuberant ears bulbous nasal tip malar flatness hooded eyelids
22q11 deletion syndrome immune system disorders
recurrent RTI’s in infancy
autoimmune pheonomena
types of 22q11 deletion syndrome
complete Digeorge anomaly = diGeorge +thymus aplasia
atypical complete Digeorge anomaly
typical complete DiGeorge anomaly
Manging PID
symptomatic - prevent infection
causative - gene therapy, Ig substitution, thymus transplant, stem cell transplant
genetic counselling and prenatal diagnosis
One causative treatment for DiGeorge
thymus transplant
