الفهرس 
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Abstract
SUMMARY
n the present study, we aimed to detect characterization of
the different gene polymorphisms in human killer cell
immunoglobulin-like receptor (KIR2) gene and the multi-drug
resistance (MDR1) gene, in childhood ITP patients . Also, to
study the potential role of these polymorphisms in relation to
chronicty and response of ITP to different treatment modalities.
This study was conducted at Pediatric Hematology
Clinic, Children Hospital, Ain Shams University.
The study group included (21) acute ITP patients.
Twelve males representing (57%) and nine females
representing (43%). Twenty seven chronic ITP cases were (12)
males representing (45%) and (15) females representing
(55%). The age ranged at diagnosis between (32 -90) months in
acute patients and between (60-150) months in chronic patients.
The control group included 35 normal healthy subjects of
comparable age and sex.
All patients were subjected to detailed history taking,
clinical evaluation, detailed anthropometric assessment and
laboratory investigations including complete blood count and
viral markers when indicated and polymorphisms of human
killer cell immunoglobulin-like receptor (KIR2) gene and the
multi-drug resistance (MDR1) gene.
I
Summary
143
In the present study, among the acute ITP patients groups
on IVIG and those on steroids; the KIR2DL2-/ KIR2DS2-
genotype was the most prevalent genotype with an incidence of
(45.45%) in the group on IVIG and nearly similar incidence of
(44.4%) in the acute ITP patients group on steroids. The
KIR2DL2+/ KIR2DS2+ was (33.3%) among the acute ITP
patients group on steroids.
The KIR2DL2+/ KIR2DS2- and the KIR2DL2-/
KIR2DS2+ genotypes were (27.2% each) among the acute ITP
patients group on IVIG compared to an incidence of (11.1%)
for each genotype among the acute ITP patients group on
steroids.
Again, among both of the chronic ITP patients groups
(on steroids and non-steroids group); the KIR2DL2-/
KIR2DS2- genotype was also the most prevalent with an
incidence of (40%) in the steroid group compared to (56.25%)
in the non-steroid group.
The KIR2DL2-/ KIR2DS2+ genotypes and KIR2DL2+/
KIR2DS2+ were (30% each) among the chronic ITP patients
groups on steroids. On the other hand, the KIR2DL2+/
KIR2DS2- genotype was (37.5%) among the chronic ITP
patients group on non-steroidal treatment.
Also, there was a significant difference in response to
second line of treatment between KIR2 genotypes in chronic
ITP patients.
Summary
144
There was a high significant difference between best
platelets response to second line of treatment among chronic
ITP patients and KIRDL2-/KIRDS2- & KIRDL2+/KIRDS2- .
Also, there was a significant difference in platelets at initial
presentation among chronic ITP patients between KIRDL2-
/KIRDS2- & KIRDL2+/KIRDS2- . Season, gender, family
history and clinical presentation among KIR2 genotypes in
acute and chronic ITP patients were not significant. Also, viral
markers (CMV&EBV), bleeding score and bone marrow
pictures among KIR2 genotypes in acute and chronic ITP
patients were not statistically significant.
In our study, MDR1 genotypes and allele distribution of
childhood ITP patients was not statistically different in acute
and chronic cases. CT genotype showed the highest distribution
among acute and chronic representing (65%) and (51.53%)
respectively.
Among the acute ITP patients group on IVIG; the mutant
allele (T) appeared in (100%) of the patients [36.3% of the
homozygote mutant genotypes (TT) and in 63.6% of the
heterozygote genotypes (CT)] compared to (88.87%) of the
patients [22.2% of the homozygote mutant genotypes (TT) and
in 66.67% of the heterozygote genotypes (CT)] of the MDR1
gene of the MDR1 gene among the acute ITP patients group on
steroids.
Summary
145
On the other hand, no wild type allele was detected in the
acute ITP patients group on IVIG, while the wild type allele
was detected in 11.1% of the patients among the acute ITP
patients group on steroids.
Again, the mutant allele (T) appeared in (100%) of the
chronic ITP patients group on steroids [50% of the homozygote
mutant genotypes (TT) and in 50% of the heterozygote
genotypes (CT)] of the MDR1 gene compared to an incidence
of (87.5%) among the chronic ITP patients group on IVIG
[18.75% of the homozygote mutant genotypes (TT) and in
68.75% of the heterozygote genotypes (CT)] of the MDR1
gene. On the other hand, no wild type allele was detected in the
chronic ITP patients group on steroids compared to only an
incidence of 12.5% among the chronic ITP patients group on
non-steroids.
In the present study, there were a significant difference in
the age at diagnosis between CC, CT and TT genotypes of
MDR1 gene among acute ITP patients. Younger age was
among CT genotype with mean age 32 months (±20.605) and
older age was among CC genotype with age 90 months
(±25.4558).
There was a significant difference in platelets at initial
diagnosis between CC, CT & CT genotypes of MDR1 gene
among acute ITP patients. Also, there was a significant
difference in platelets at diagnosis between CC, CT and TT
Summary
146
genotypes of MDR1 gene in chronic ITP patients .Lower
platelets count was among CC genotype and higher platelets
count was among TT genotype.
Also, there was a significant difference in the skin
manifestation between CC, CT & TT genotypes in chronic
patients. 81.50% of chronic patients were among (+ve) skin
manifestation with highest prevalence among TT genotype
representing (100%), then CT representing (82.4%) and CC
representing (0%).
There was a significant difference in bleeding/orifices as a
clinical manifestation of chronic ITP patients between CC,
CT& TT genotypes of MDR1 gene. chronic ITP patients with
no bleeding manifestation were (66.7%) with highest
prevalence among TT genotype representing (100.0%) then CT
representing (58.8%) and CC genotypes representing (0%).
Season, gender, family history and type and response to
third line of treatment among MDR1 genotypes in chronic ITP
patients were not statistically significant. Also, viral markers
and bone marrow picture did not show a statistical significant
differences between CT& TT genotypes of MDR1gene in
chronic and acute ITP patients. The initial bleeding score did
not show a statistical significant differences between CC, CT&
TT genotypes of MDR1 gene in chronic and acute ITP patients.
There were not significant differences in WBCS, HB, best
platelets response to first line treatment and time of best first
response between CC, CT and TT genotypes in acute ITP
patients