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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 Part Eight: Summary [122] 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 Part Eight: Summary [123] 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. |