Primary Immunodeficiency Flashcards
what are the hallmarks of immune deficiency
serious persistent unusual recurrent infections
Failure of stem cells to differentiate along myeloid lineage
1y - reticular dysgenesis 2y - after stem cell transplantation
Specific failure of neutrophil maturation
kostman syndrome cyclic neutropaenia
what is the most severe form of inborn SCID
reticular dysgenesis
presentation of kostmann syndrome
severe chronic neutropaenia fever, irritable, failure to thrive, oral ulceration
kostmann treatment
prophylactic antibiotics and antifungals stem cell transplant or G-CSF
leucocyte adhesion deficencies
disorders of phagocyte migration - dont exit blood stream
leucocyte adhesion deficiencies signs
recurrent bacterial infection high neutrophil count in blood no pus at infection site
what is leucocyte adhesion deficency caused by
genetics defect in CD18
name some opsonins
complement C3b, IgG and CRP
name some ways of direct and indirect phagocyte recognition of pathogen
DIRECT
- Toll like receptors
- Scavenger receptors
- Lectin receptors
INDIRECT
opsonins
what is an epitope
the part of an antigen molecule to which an antibody attaches itself
how do opsonins bind to surface
CR1 and Fc receptor
chronic granulomatous disease
mutations in genes encoding NADPH oxidase enzymes, results in failure of oxidative killing
chronic granulomatous disease signs
excessive inflammation and granuloma formation
what can chronic granulomatous disease be demonstrated by
NBT test
what do defects in cytokines and their receptors make people susceptible to
mycobacterial infections - IL12 - IFN gamma network
what does IL-12 induce T cells to secrete
IFN gamma
where are immature T cells taken
thymus - mature here
what does SCID result from
failure of production of lymphocytes
what is seen on skin in SCID
graft vs host disease
clinical phenotype of SCID
FHx of early death
diarrhoea
unwell by 3 months infections
when does maternal IgG decline and neonatal IgG production start
3 months
what is X linked SCID caused by
mutation of component of IL2 receptor
what does DiGeorge syndrome result from
deletion of chromosome 22q11 developmental defect of the 3rd/4th pharyngeal pouch
Di George syndrome CF
cleft palate
heart disease
low set weird ears
high forehead
what occurs in DiG syndrome
T cell immuno deficiency as due to failure of thymic development there is nowhere for the T cells to mature
Hypocalcaemia secondary to hypoparathyroidism
what is bare lymphocyte syndrome
failure of expression of HLA molecules
what is autoimmune lymphoproliferative syndrome
failure of normal apoptosis
what is Bruton’s X-linked hypogammaglobulinaemia
failure to produce mature B cells
what is common variable immune deficiency
low IgG IgA and IgE
what is CVID associated with
autoimmune disease
CF of CVID
recurrent bacterial infections and granulomatous disease
what is selective IgA def.
failure of IgA production
investigations of B cell def. first line
Total white cell count and differential
Serum immunoglobulins
Serum and urine protein electrophoresis
investigations of B cell def. 2nd line
quantitation of B and T cells
