Investigation of Carnitine Levels in some Biological Fluids


  • Ajjl A. Alzamily College of Medicine, University of Al-Qadisiyah, Iraq
  • Amjad J. Hameedi College of Medicine, University of Al-Qadisiyah, Iraq
  • Akeel Al-kafagi AL-Diwaniyah Teaching Hospital, Al-Qadisiyah, Iraq


Urine, Saliva, Carnitine, Autism, ASD


Autism spectrum disorder (ASD) refers to a certain degree of neurodevelopmental disorder in children that usually occurs during the first years of life. Until now, the causes and treatments for autism have remained obscure. Research has shown that ASD has been linked to a genetic defect in carnitine metabolism. This study was aimed at evaluating the levels of carnitine in the saliva and urine of children with ASD towards proposing a diagnostic biomarker. Sixty children ranging in age from 2 to 13 years were recruited for the study. The subjects were grouped into ASD and healthy control groups. Saliva and urine were collected from both groups. The enzyme-linked immunosorbent assay (ELISA) technique was used to estimate the total carnitine in the saliva and blood samples of the autistic children and the healthy control group. The results of the study showed that there was no significant difference in the level of salivary carnitine between the children with ASD (2.22±0.37 nmol/ml) and the normal children (2.33±0.86 nmol/ml). Meanwhile, there was a significantly lower average amount of carnitine in the urine of the ASD group (28.61±8.16 nmol/ml) compared to the control group (36.13±13.12 nmol/ml). A cut-off value of < 30.23 nmol/ml was obtained with a sensitivity level of 76.7 % and a specificity level of 66.7 %, with an overall accuracy level of 70.1 %.The findings of the study suggest that low urinary carnitine is a strong predictor of autism, and a cut-off value of < 30.23 nmol/ml provided a reliable diagnostic tool.


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How to Cite

Alzamily, A. A., Hameedi, A. J., & Al-kafagi, A. (2024). Investigation of Carnitine Levels in some Biological Fluids: Tropical Journal of Natural Product Research (TJNPR), 8(1), 5997–6000. Retrieved from