الفهرس 
INTRODUCTIONOnly 14 pages are availabe for public view
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Abstract
Autism is a long-term disability and a developmental disorder in which
many studies suggested an association between serum low levels of Zn
and high Cu. In addition, Zinc to copper (Zn/Cu) ratio can be a
biomarker of ASD as it is abnormally low in individuals with autism.
In medical practice, the levels of these trace elements should be
regularly monitored and checked under control. This can be achieved
by determining their levels in the body at the cellular level using
different analytical techniques. Thus, it is indispensable to avail
simple, accurate, selective and reliable alternative analytical methods
that conveniently and promptly assess these elements levels.
The aim of the present study was to determine the levels of metals in
blood (zinc (Zn), copper (Cu), as well as the Zn/Cu ratio of children
with autism spectrum disorder (ASD). The assay is done using a new
technology quantum magnetic resonance analysis (QMRA) method
and comparing its results by a reference traditional testing laboratory
method (Direct Colorimetry) to determine the sensitivity and
specificity of the new measurement method.
The study was performed in a group of children with ASD (N=30,
average age=8.3 years) and a control group of normal or typically
developing (TD) children (N=30, average age=7.8 years) matched in
terms of sex and age. Measurement of Zn and Cu in study subjects was
performed by the QMRA method via a QMRA-998 8th Generation
device and in subjects’ plasma by direct colorimetric method. Results
were compared across groups using descriptive statistics, Pearson’s
correlation coefficients, Chi-Square significance and analysis of
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variance (ANOVA). In addition, a linear regression analysis and a
sensitivity and specificity cross-tabulation test was performed to
evaluate the QMRA method in measuring Zn and Cu levels.
First, analysis of the anthropometric measurements of ASD and control
groups revealed significant differences between groups only with head
circumferences. Clinically, the ASD group showed more relevant GIT
symptoms such as diarrhea and pica, higher frequencies of upper and
lower recurrent chest infections and more observable neuropsychiatric
and behavioral findings, especially inattention and temper tantrums.
Significant differences between both groups as regards Zn levels by
both methods were found and coincided with the gastrointestinal
system, respiratory system and neuropsychiatric and behavioral
findings. The level of general cognitive abilities categories (IQ score)
was low in the ASD group and inversely and significantly correlated
with CARS score. The CARS test showed most of the ASD group in
the severe category (37-40). In addition, the ASD group demonstrated
more white cells subtypes’ deficiencies, especially those related to
signs of Covid-19 and low immunity and coincided with Zn levels by
both methods.
Both methods showed lower means for Zn levels in the ASD group
than the control group with significant differences between groups
when measured by QMRA. In general, there was a linear regression
relationship between the two methods when measuring Zn levels with
the equation (ZnSerum =13.924* ZnQMRA + 46.478; R2=0.1832) but
they differed in their measurements for Cu levels. Measuring Cu by
QMRA showed incoherent and heterogeneous Cu levels in the study
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sample almost in the opposite direction of the serum results. The
relationship was evidenced by wide-spaced scattering of values away
from the regression trendline, which was almost isometric with the
equation (CuSerum =4.6743* CuQMRA + 121.49; R2=0.0017). Finally,
evaluation of method sensitivity was 84% when measuring Zn levels
but only 60% when measuring Cu levels. Specificity was 87% for Zn
but only 60% for Cu. Moreover, the ability of QMRA to detect patients
having abnormal Zn values when test is positive or Positive Predictive
Value (PPV) is (91%) and its ability to detect not having abnormal Zn
values when test is negative or Negative Predictive Value (NPV) is
(77%). On the other hand, for Cu, PPV is 43% and NPV is 75%.
Conclusively, the results of our study revealed significantly lower
serum Zn level, higher serum Cu level and lower Zn/Cu ratio in the
ASD group than normal reference values and when compared to
another group of normal typically developing children. The low Zn
level was also observed when measured by QMRA. Considering the
results of the present study, it would be reasonable to add Zn to the
food in all those children with ASD who have reduced levels of Zn or
low Zn/Cu ratio in the plasma and QMRA can be used to screen levels
of Zn in humans.