Primary immunodeficiency disorders. Flashcards
(114 cards)
immunodeficiency can be classified into ?
specific immunodeficiency
non specific immunodeficiency
primary and secondary
what is the difference between specific and non specific immunodeficiency ?
specific immunodeficiency involve abnormalities of the b and cells of the adaptive immune system
non specific immunodeficiency involves abnormalities in the compliment system , neutrophils and phagocytes which is INNATE immunity
what is the difference between primary and secondary immunodeficiency
primary immunodeficiency is related genetics being the sole cause
while secondary immunodeficiency is triggered by environmental causes such as a bacteria
infections encountered in immundefcient patients falls into two categories what are these categories ?
patient with defect in antibodies and compliment proteins and phagocytes = susceptible to recurrent infections from capsulated bacteria such as h influenzas , strep yo, staph areas giving pyogenic infections
patient defect in cell mediated immunity from t cells are susceptible to severe life threatening infection from micro-organism which is ubiquitous in the environment = opportunistic infections
such as candida and chicken pox
what are the primary b cell immunodeficiencies ?
x linked agammaglobulinemia
Iga deficiency
IgG subclass deficiency
immunodeficiency with increased IgM
common variable immunodeficiency
transient hypogammaglobulinemia of infancy
which gender does x linked (bruton) agammaglobulinemia affect the most
males
in x linked agammaglobulinemia when do the signs and symptoms start to appear
6-12 month of life because they receive passive immunity from the IgG that crossed the placenta
what is the pathophysiology of x linked bruton agammaglobulinemia
the pre b cell do not go into an IMmature b cells so there is NORMAL amount of pre b cell in the bone marrow however absent to few B cells in the blood
this is due to a cytoplasmic bruton tyrosine kinase enzyme defect which is linked to the maturation of the b cells
the defect in the gene is in the LONG arm of the x chromosome
what are the signs of x linked bruton Agamma globulinemia
lymphoid hypoplasia - tonsils adenoid no splenomegaly or lymphadenopathy
Present with recurrent pyogenic infections with Streptococcus pneumoniae, Haemophilus influenzae, Mycoplasma pneumoniae
respiratory tract = sinusitis , otitis media and pneumonia ,
meningitis
no viral except : hepatitis virus hepatitis enterovirus (polio , coxsackie) = myositis , CNS infections echovirus
how do we diagnose x linked gamma globulinemia
history of recurrent infection mostly in the respiratory tract and lymphoid hypoplasia
blood test lack of b cells determined by CD19 and CD20 marker
= flow cytometry to show there an no mature b cells circulating
ABSCENCE OF CD19 B CELLS PARTICULARLY
low levells or absent of all antibodies total below 100mg/dl
western blot to show if the Btk protein is expressed
women with an XLA patient in their family should seek what ?
genetic counselling
when having x linked hypogammaglobulinemia what should be considered
avoid LIVE ATTENUTAED VACCINES scuh as :
polio vaccine should not be administered - for there can be paralyse or fatal CNSinfecions
messes , mumps and rubella
no allergic reactions since no IgE is made
they do not have EBV because no b cells
how can we distinguish from x lined agammaglobulinemia and transient hypogammaglobulineiam
natural antibodies to a and b red blood cell and antigens through immunisation is very low in xla whereas normal in transient hypogammaglobulinemia
and normal immunisation action
XLA patienta are more susceptible to ?
septic arthritis
the genes for many immunodeficiency are located on which chromosome ?
the x chromosome
which is the most common immunodeficiency ?
Iga immunodeficiency
who are more susceptible to IgA deficiency
predisposition to caucasians
in pedigree of CVID in the family
associated with autoimmune disorders
more common in diabetes type 1
celiac disease associated
what is the clinical presentation of IgA deficiency ?
type 3 hypersensitivities - immune complex diseases
IgA antibody that protects against infections of the mucous membranes lining the mouth, airways, and digestive tract
Most people remain healthy never diagnosed
sinopulmonary pyogenic infections and gastrointestinal infections esp - giardiasis
can cause non haemolytic transfuse reactions - because serum antibodies TO IgA NOTED
why are individuals with deficiency to IgA susceptible to pyogenic infections ?
20 percent of the IgA deficient people also have deficicny for IgG2 andG4 subclass deficiency = resulting in recurrent pyogenic infections
what is the pathophysiology of IgA deficiency ?
NORMLAMOUNT OF B CELLS
change in terminal differentiation of B cells
how do we diagnose IgA deficicny ?
diagnosis cannot be made until 4 years of age when the iga levels should come to mature level
less than 5 mg/dl or absence of IgA serum conc and other antibodies are normal
what is the treatment for x linked agammaglobulinemia ?
blood pool extracted from thousand of blood donors of intravenous infusion of immunoglobulin IVIg - esp IgG every week for life
attempt at IgG level of 800mg/kg
its not a cure but increase the quality of life and life span generating passive immunity
prophylactic antibiotics - local preferred
IgA immunodeficiency has the chance to evolving into ?
CVID
what is the treatment of IgA deficiency ?
identification of co morbid condition
prophylactic antibiotics