3. Immunodeficiency
⢠Immune systemâs ability to fight infectious
diseases is completely absent or
compromised.
⢠Types:
ďPrimary Immunodeficiency
ďSecondary Immunodeficiency
4. Immunodeficiency
⢠Cause for Immunodeficiency:
Human Immune system:
ďśVery specific
ďśDependent on memory of cells and
lymphocytes that recognise foreign antigen
and infected cells respectively.
⢠Any alterations in these functions
Immunodeficiency.
5. Classification
â˘Most are genetically
determined
â˘Less common
â˘May arise as complications
of cancers, infestations,
malnutrition, or side effects
of immunosuppression,
Irradiation and
chemotherapy.
â˘More common
Primary
Immunodeficiency
Secondary
Immunodeficiency
6. Primary Immunodeficiencies
⢠A group of disorders characterized by an
impaired ability to produce normal immune
response.
⢠Cause: mutations in genes involved in the
development and function of immune organs,
cells, and molecules.
⢠Genetically determined.
⢠Usually diseases of infancy & childhood.
7. Primary Immunodeficiency
⢠Most important feature:
⢠High Incidence in Males: Why ?
⢠6 X-linked IDâs have been
described:
5 - Affect
Lymphocytes
1- Affect
Phagocyte
8.
9. Table 1. Characteristic infections of the primary immunodeficiencies
component primary pathogen primary site clinical example
T-cells
intracellular, bacteria
viruses, protozoa, fungi,
non-specific SCID, DiGeorge
B-cells
pneumococcus,
streptococcus,
haemophilus
lung, skin, CNS
IgG, IgM deficiency
IgG, IgM deficiency
enteric bacteria and
viruses
GI, nasal, eye IgA deficiency
phagocytes
Staphylococcal,
Klebsiella
Pseudomonas,
lung, skin,
regional lymph
node
Chronic
granulomatous
disease (CGD)
complement
neisseria, Haemophilus,
pneumococcus,
streptococcus
CNS
lung
skin
C3, Factors I and H,
late C omponents
10. Severe Combined
Immunodeficiency(SCID)
⢠Synonyms: Glanzzman-Rinker syndrome,
Bubble Boy Disease, Thymic Alymphoplasia
⢠Genetic disorder characterised by absence of
T-lymphocytes.
⢠Impairment of both cellular & humoral
response
⢠Specific defects in antigen presentation &
functional immune molecules.
12. SCID-Types
⢠Main Types:
ďAutosomal recessive (-ve T & B cells)
ďX-linked recessive(+ve B cells)
⢠Other important types:
ďNezelof Syndrome
ďSCID associated with ADA & PNP deficiency.
13. Features of SCID
⢠Absent tonsils
⢠Small or absent lymph nodes
⢠Absent thymic shadow
⢠Lymphopenias
⢠Decreased Number of T cells
⢠Severe agammaglobulinemia (Swiss type of
agammaglobulinemia)
⢠No IGâs usually present
16. Brutonâs X-linked Agammaglobuinemia
⢠Primarily B-cell defect
⢠Boys-more affected
⢠Severe reduction in γ-globulins
⢠IGâs, circulating and marrow B-cells.
⢠Probable cause: Molecular defect at
Xq22.Mutation of bruton tyrosine kinase.
⢠Therapy: IV IGâs.
17. DiGeorgeâs syndrome
⢠Also called thymic hypoplasia
⢠Congenital disorder
⢠Abnormalities in structure derived from 3rd
and 4th pharyngeal pouches
⢠Predominantly T cell defect
⢠Charactersitics: Neonatal tetany(absence of
parathyroid)
⢠Therapy: Thymic transplants
18. ⢠Cleft palate
⢠Antimongoloid eyes
⢠Short philtrum with
fish-mouth appearance ,
⢠Micrognathia
⢠Low set pixie-like ears
⢠Short palpebral fissures
Facial features of children with DiGeorge syndrome
26. Chronic Granulomatous Disease
⢠Incidence:1:10,00,000
⢠Defect: Inability of phagocytes to produce
superoxide ineffective reduction of O2.
⢠Failure to express respiratory burst associated
with phagocytosis.
⢠Central necrosis and granulomatoid response
in lung, liver, bone , skin and lymph nodes.
⢠Presence of numerous pigmented
macrophages.