Serum IL-6 and IL-18 Responses in Pediatric COVID-19: Role of Vitamin D Status in a Cohort from Azerbaijan

Huseynova, I. Y.; Hasanov, A. Q.; Sultanova, N. H.; Mammadova, F. M.; Taghi-zada, T. G.; Gafarov, I. A.; Allahverdiyeva, A. B.

doi:10.64898/2025.12.03.692155

bioRxiv · 10.64898/2025.12.03.692155

Serum IL-6 and IL-18 Responses in Pediatric COVID-19: Role of Vitamin D Status in a Cohort from Azerbaijan

Huseynova, I. Y.·Hasanov, A. Q.·Sultanova, N. H.·Mammadova, F. M.·Taghi-zada, T. G.·Gafarov, I. A.·Allahverdiyeva, A. B.

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Abstract

BackgroundThis study investigated the effects of COVID-19 infection and vitamin D status on inflammatory cytokine levels in children during the pandemic. A cohort of 170 children aged 1-17 years with PCR-confirmed SARS-CoV-2 infection was enrolled. Serum levels of IL-6 and IL-18 were analyzed in relation to vitamin D status and COVID-19 diagnosis. Our analysis revealed that children with vitamin D deficiency exhibited a trend toward increased levels of IL-6 and IL-18 compared to those with normal vitamin D levels; however, this association did not reach statistical significance. In contrast, COVID-19 infection was associated with significantly higher cytokine levels relative to healthy controls. These findings suggest a potential modulatory role of vitamin D in pediatric inflammatory responses to SARS-CoV-2, meriting further investigation through prospective studies.

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Huseynova, I. Y., Hasanov, A. Q., Sultanova, N. H., Mammadova, F. M., Taghi-zada, T. G., Gafarov, I. A., Allahverdiyeva, A. B.. 2025-12-05. Serum IL-6 and IL-18 Responses in Pediatric COVID-19: Role of Vitamin D Status in a Cohort from Azerbaijan. https://doi.org/10.64898/2025.12.03.692155

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