title: Effects of latent toxoplasmosis on autoimmune thyroid diseases in pregnancy.
abstract: BACKGROUND
  Toxoplasmosis, one of the most common zoonotic diseases worldwide, can induce various hormonal and behavioural alterations in infected hosts, and its most common form, latent toxoplasmosis, influences the course of pregnancy. Autoimmune thyroid diseases (AITD) belong to the well-defined risk factors for adverse pregnancy outcomes. The aim of this study was to investigate whether there is a link between latent toxoplasmosis and maternal AITD in pregnancy.
  
  
  METHODS
  Cross-sectional study in 1248 consecutive pregnant women in the 9-12th gestational weeks. Serum thyroid-stimulating hormone (TSH), thyroperoxidase antibodies (TPOAb), and free thyroxine (FT4) were assessed by chemiluminescence; the Toxoplasma status was detected by the complement fixation test (CFT) and anti-Toxoplasma IgG enzyme-linked immunosorbent assay (ELISA).
  
  
  RESULTS
  Overall, 22.5% of the women were positive for latent toxoplasmosis and 14.7% were screened positive for AITD. Women with latent toxoplasmosis had more often highly elevated TPOAb than the Toxoplasma-negative ones (p = 0.004), and latent toxoplasmosis was associated with decrease in serum TSH levels (p = 0.049). Moreover, we found a positive correlation between FT4 and the index of positivity for anti-Toxoplasma IgG antibodies (p = 0.033), which was even stronger in the TPOAb-positive Toxoplasma-positive women, (p = 0.014), as well as a positive correlation between FT4 and log2 CFT (p = 0.009).
  
  
  CONCLUSIONS
  Latent toxoplasmosis was associated with a mild increase in thyroid hormone production in pregnancy. The observed Toxoplasma-associated changes in the parameters of AITD are mild and do not seem to be clinically relevant; however, they could provide new clues to the complex pathogenesis of autoimmune thyroid diseases.
authors.affiliation: Department of Philosophy and History of Science, Faculty of Science, Charles University, Prague, Czech Republic.
authors.forename: Šárka
authors.initials: Š
authors.lastname: Kaňková
authors.affiliation: Department of Philosophy and History of Science, Faculty of Science, Charles University, Prague, Czech Republic.
authors.forename: Lucie
authors.initials: L
authors.lastname: Procházková
authors.affiliation: Department of Philosophy and History of Science, Faculty of Science, Charles University, Prague, Czech Republic.
authors.forename: Jaroslav
authors.initials: J
authors.lastname: Flegr
authors.affiliation: Department of Obstetrics and Gynaecology, General University Hospital and First Faculty of Medicine, Charles University, Prague, Czech Republic.
authors.forename: Pavel
authors.initials: P
authors.lastname: Calda
authors.affiliation: Institute of Clinical Biochemistry and Laboratory Diagnostics, General University Hospital and First Faculty of Medicine, Charles University, Prague, Czech Republic.
authors.forename: Drahomíra
authors.initials: D
authors.lastname: Springer
authors.affiliation: Third Department of Medicine, General University Hospital and First Faculty of Medicine, Charles University, Prague, Czech Republic.
authors.forename: Eliška
authors.initials: E
authors.lastname: Potluková
mesh_terms: D000293:Adolescent; D000328:Adult; D000913:Antibodies, Protozoan / Q000097:blood / Q000276:immunology; D001323:Autoantibodies / Q000097:blood / Q000276:immunology; D001327:Autoimmune Diseases / Q000453:epidemiology / Q000209:etiology*; D003430:Cross-Sectional Studies; D018153:Czech Republic / Q000453:epidemiology; D005260:Female; D006801:Humans; D007074:Immunoglobulin G / Q000097:blood / Q000276:immunology; D008875:Middle Aged; D011247:Pregnancy; D011248:Pregnancy Complications / Q000453:epidemiology / Q000209:etiology*; D011256:Pregnancy Outcome; D012307:Risk Factors; D013959:Thyroid Diseases / Q000453:epidemiology / Q000209:etiology*; D013963:Thyroid Hormones / Q000097:blood; D014123:Toxoplasmosis / Q000150:complications* / Q000175:diagnosis; D055815:Young Adult
chemical_list: D000913:Antibodies, Protozoan; D001323:Autoantibodies; D007074:Immunoglobulin G; D013963:Thyroid Hormones