Answer
- Hematopiotic Stem-cells transplantation ( = bone marrow grafting )
is the treatment of choice for severe combined immunodeficiency
( SCID ).
- despite successful T-cell engraftment in tranplanted patients, B cells
is not always achieved.
- umbilical cord blood is an alternative ( 2nd choice ) source of stem cells
for transplantation in children with SCID and has a higher likelihood of
B cell reconstitution.
- umbilical cord blood as a source of Stem cells lead to rapid and reliable
recovery and have low viral transmission.
Work Step by Step
- Hematopiotic Stem-cells transplantation ( = bone marrow grafting )
is the treatment of choice for severe combined immunodeficiency
( SCID ).
- despite successful T-cell engraftment in tranplanted patients, B cells
is not always achieved.
- umbilical cord blood is an alternative ( 2nd choice ) source of stem cells
for transplantation in children with SCID and has a higher likelihood of
B cell reconstitution.
- umbilical cord blood as a source of Stem cells lead to rapid and reliable
recovery and have low viral transmission.
Severe Combined Immunodeficiency ( SCID )
- this may be due to failure of differentiation of stem
cells into T and B cells
however the explanation of this failure is not known.
- both humoral and cell mediated immunity are
deficient.
- these infants suffer from all kinds of opportunistic
infections : viral, bacterial, fungal and protozoal.
- death occurs early in childhood ( before 1 year ).
- the disease may be inherited in an X-linked
recessive or autosomal recessive manner, however
sporadic forms occur.
# Immunologic Findings :
1- Hypoplasia of the Thymus as shown by chest
X-ray.
2- Lymphopenia and decreased T cell number and
functions:
- impaired response to Phytohemagglutinin
( PHA ).
- Impaired Delayed Hypersensitivity reactions.
3- Decreased B cell number and function :
- Serum Immunogloulins are absent or decreased
- No response to antigenic stimuli.
# Treatment :
patients may be made completely normal by grafting
with histocompatible bone marrow from a sibling.
incompatible grafts will lead to a fatal " graft versus
host " ( GVH ) reactions.
- Gammaglobulins may be administered.
- Antibiotics are used for treatment of infections.
