Interleukin Activity in Miscarried Women with Toxoplasmosis and Anti Thyroid Peroxidase (Anti-TPO).

Background: We aimed to investigate the presence of thyroid peroxidase antibodies (anti-TPO) in women with spontaneous abortion, both with and without toxoplasmosis. This was achieved by evaluating and comparing the serum levels of interleukins IL-4, IL-6, IL-10, IL-17, and TNF-α in women who experienced abortion due to toxoplasmosis, categorized by positive and negative anti-TPO status, with those who were toxoplasmosis-negative and also negative for anti-TPO.

Methods: We evaluated the serological presence of IgG and IgM antibodies to Toxoplasma using an ELISA method, in Samarra City, Salah al-Din Governorate, Iraq in 2021-2022. A sample of 153 women with spontaneous abortion were enrolled. We also measured the serum levels of interleukins IL-4, IL-6, IL-10, IL-17, TNF-α, and anti-TPO using the same technique.

Results: Overall, 103 were Toxoplasma-positive. Of these, 14 had positive anti-TPO results (13.5%), compared to only 3 positive cases among the 50 matched controls who were Toxoplasma-negative (6.0%). The difference between Toxoplasma-positive and Toxoplasma-negative women regarding anti-TPO status was statistically significant for interleukins IL-4 (P=0.010), IL-6 (P=0.017), and IL-10 (P=0.003), but not for IL-17 or TNF-α. Additionally, the statistical analysis revealed a highly significant difference in the average concentrations of interleukins IL-4 (P=0.013) and IL-10 (P<0.001) between the Toxoplasma-positive/anti-TPO-positive group and the Toxoplasma-negative/anti-TPO-negative group of aborted women.

Conclusion: Elevated concentrations of IL-4, IL-10, and IL-6 have been associated with women undergoing recurrent miscarriages and negative anti-TPO results. The complex interaction between pro-inflammatory and anti-inflammatory cytokines is essential for immunological balance and pregnancy outcomes in a condition of toxoplasmosis. An increase in IL-4 and IL-10 levels in anti-TPO-positive individuals may lead to an imbalance in immune response, facilitating the development of autoimmune thyroid disease.