Immunodeficiency Flashcards
(53 cards)
what is immunodeficiency?
Absence or failure of the normal function of the
immune system
what results of immunodeficiency?
increased susceptibility to infection
why are dentists expected to treat increasing numbers of immunodeficient patients?
as people with once-fatal diseases continue to
survive them
what are the classification of immunodeficiency?
- specific-involving abnormalities of B and T cells-problem with adaptive immune system
- non-specific - involving abnormalities in complement or phagocytes- problems with innate immune system
Describe primary immunodeficiency .
primary - due to intrinsic defects,often genetic (age-related decline)
Describe secondary immunodeficiency.
Results from extrinsic factors:
- drug therapies for cancer or autoimmune disease
- irradiation (e.g. in cancer treatment)
- organ or bone marrow transplantation protocols
- malnutrition, alcoholism
- certain infections
Describe B cell immunodefiences.
- Low serum levels (hypogammaglobulinaemia)
- recurrent pyogenic infections i.e sinusitis - ifutreated, severe obstructive lung disease develops from recurrent pneumonia
- mostly occur as primary (born with)
immunodeficiencies - rare with exception of IgA deficiency
- Treatment -intravenous replacement therapy with Ig
Name the infectious susceptibility and oral manifestations of No Ig production.
IS-Respiratory infections with extracellular bacteria,
Giardia infection in GI tract
Enterovirus infections
OM-Possible sepsis from abscessed teeth
Name the infectious susceptibility and oral manifestations of severely decreased or No IgG production.
IS-Respiratory infections with extracellular bacteria
Some patients asymptomatic
OM-Possible sepsis from abscessed teeth ,
Some patients asymptomatic
Name the infectious susceptibility and oral manifestations of severely decreased or No IgA production.
IS-Respiratory and GI tract infections Some patients asymptomatic OM-Candidiasis , Oral ulcerations, Some patients asymptomatic
what are patients with no T cells or poor T cell function susceptible to?
opportunistic infections e.g herpes
what is T cell immunodeficiencies due to?
- MHC defects
- CD40 ligand deficiency
- CD3 mutations
- Decreased T cell number
since B cell function depends on T cell function , what does T cell immunodeficiencies also result in?
humoral
deficiency i.e. combined immunodeficiency
how severe are primary T cell immunodeficiencies?
rare and often fatal e.g severe combined immunodeficiency (SCID)
What are side effects of patients with SCID ?
-Failure to thrive, repeated infections i.e herpes simplex
-During first 6-9 months maternally acquired antibodies offer some
protection. Thereafter bacterial infections much
more common
Name some oral manifestations in SCID.
- Candidiasis
- Herpes infections
- Recurrent ulcerations of tongue and buccal mucosa
- Severe necrotizing gingivostomatitis
what does AIDS stand for?
Acquired Immunodeficiency Syndrome
or
Acquired Immune Deficiency Syndrome
how is secondary T cell immunodeficiency caused by?
caused by infection with HIV (human immunodeficiency virus)
how is HIV transmitted?
- Sexual contact
- Transfer via placenta or milk from mother
to infant - Blood transfusion
- Needle sharing - intravenous drug use
- Needlestick injuries
Describe how HIV infiltrates cell.
-HIV interacts with our helper T cells , major receptor of HIV to bind to CD4( found in helper t cells)
-Release of RNA
-Reverse transcibred –double stranded DNA forms -integrated into host DNA
Cell activation –HIV rna is transcibred
Proteins for extrerior part of virus translated and released
Describe clinical stages of AIDS.
-Infection with HIV -
many individuals asymptomatic
some develop transient fever, swollen lymph nodes,
sore throat, rash
-Abs against HIV proteins take 2-6 weeks to develop
Standard HIV infection tests detect these
-After 1o infection, period of latency (no or few
symptoms)
Progression to AIDS takes 2-15 years
when is HIV then classified as AIDS?
Classified as AIDS when CD4+ T cells <200 cells/l
what are the clinical stages of AIDS?
a) Major opportunistic infectionsE.g. Pneumocystis jirovecii pneumonia,Cryptosporidial diarrhoea
b) malignancy e.g. Kaposi’s sarcoma (tumour of endothelial cells)
c) Thrombocytopenia (low platelet count)
d) nervous system disease - dementia and paralysis
how can HIV be treated?
-HIV infection can be controlled with highly active antiretroviral therapy (HAART)
