الفهرس 
1-Acknowledgment.
chapter 1 : Hypoxic Ischemic Encephalopathy.Only 14 pages are availabe for public view
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Abstract
Hypoxic Ischemic brain injury in newborn full term and
premature infants is a common and pervasive source of life time
disabilities in cognitive and locomotors function (Hilton et al.,
2006).
The incidence of hypoxic-ischemic encephalopathy is reportedly
high in countries with limited resources; however, precise figures
are not available. Birth asphyxia is the cause of 23% of all neonatal
deaths worldwide. It is one of the top 20 leading causes of burden of
disease in all age groups (in terms of disability life adjusted years)
by the World Health Organization and is the fifth largest cause of
death of children younger than 5 years (8%) (Bryce et al., 2005).
In Egypt and other developing countries perinatal asphyxia is the
most important cause of hypoxic ischemic brain damage in full term
babies and it is known to be a leader for higher morbidity and
mortality among these infants (Boo et al., 2000).
In severe hypoxic ischemic encephalopathy, the mortality rate is
reportedly 25-50% (Lawn J et al., 2005). As many as 80% of infants
who survive severe hypoxic ischemic encephalopathy develop
serious complications, 10-20% develop moderately serious
disabilities and as many as 10% are healthy. Among the infants who
survive severe hypoxic ischemic encephalopathy, 30-50% may have
serious long-term complications and 10-20% have minor
neurological morbidities (Santina Zanelli et al., 2012).
Ninety percent of the asphyxia insults occur in the antepartum
and intrapartum periods. The remainders are postpartum (Snyder
and Cloherty, 1998).
Summary Summary & Conclusion
111
Estradiol (17 β Estradiol) is sex hormone - mislabeled the
“Female Hormone” - it is also present in males; it represents the
major estrogen in humans (Pentikainen et al., 2006).
Estradiol is a pleiotropic hormone that enhances plasticity and
survival of the brain in multiple models of injury (Wise et al., 2005).
Studies data strongly suggest a positive role for estradiol
receptors (ER), specifically for ERα, in protection against delayed
cell death resulting from neurodegeneration due to ischemia (Dena
Dubal et al., 2006).
The aim of the present study is to detect Serum levels of 17 Beta
estradiol in newborns with hypoxic ischemic encephalopathy and
correlate the levels with the severity of insult and thus predict the
possible role of 17 Beta estradiol in identification of infants at high
risk and the possible early therapeutic intervention.
This study is a prospective case-control study; it was carried out
on 40 newborn infants 26 males and 14 females in the neonatal
intensive care unit at Beni Suef University hospital.
All newborns were subjected to detailed history taking, full
clinical examination and variable laboratory investigations as
complete blood picture, CRP, RBS and estimation of serum level of
17 beta estradiol using ELISA technique.
Summary Summary & Conclusion
112
The neonates in the present study were classified into two
groups:
Patients group: this included 20 neonates; 15 full term infants
and 5 preterm infants and also included 13 males and 7 females.
Newborns of patients group were further subdivided into 3
subgroups according to severity of hypoxia; mild hypoxia, moderate
hypoxia and severe hypoxia according to Sarnat and Sarnat (1976)
classification.
Control group: this group included 20 healthy neonates; their
gestational age and sex nearly matched with patients group but with
normal clinical examination.
Our study results revealed that, there was a highly statistically
significant increase in serum level of 17 beta estradiol in patients
group compared to control group and it was even higher in patients
with severe hypoxia compared to patients with moderate and mild
hypoxia.
Also there was a highly statistically significant increase in mean
value of 17 beta estradiol in patients with decreased conscious level
or abnormal muscle tone and low Apgar score at 5th minute.
Whereas, there was a statistically significant increase in mean value
of 17 beta estradiol in patients with abnormal stretch reflex, Moro
reflex and also in patients with anemia and low Apgar score at 1st
minute.
There was a highly statistically significant increase in mean value
of 17 beta estradiol in female when compared to male in control
group but there was no statistically significant difference between
mean value in males when compared to female in patients group.
There was no statistically significant difference in mean value of
17 beta estradiol in different prenatal history, different natal history
Summary Summary & Conclusion
113
and patients with seizures, abnormal suckling reflex and positive
CRP.
Assessment of the sensitivity and specificity of serum 17 beta
estradiol as marker for hypoxic insult was done and showed that it
has 100% sensitivity and 90% specificity with a cut-off value 152.5
pg/ml.
from the results of the current study, we can conclude that 17
beta estradiol levels can be used as a diagnostic test having a high
sensitivity and specificity for newborns with hypoxia and its level
increases with the increase in the severity of hypoxia, but its utility
as a neuroprotective agent could not be proven yet.