Korean J Parasitol.  2018 Apr;56(2):147-152. 10.3347/kjp.2018.56.2.147.

Serologic Tests of IgG and IgM Antibodies and IgG Avidity for Diagnosis of Ocular Toxoplasmosis

• Rahimi-Esboei B
• Zarei M
• Mohebali M
• Valian HK
• Shojaee S
• Mahmoudzadeh R
• Salabati M

• KMID: 2412733
• DOI: http://doi.org/10.3347/kjp.2018.56.2.147

Abstract

This prospective study was aimed to detect acute and chronic ocular toxoplasmosis by comparison of anti-Toxoplasma gondii IgM and IgG antibody levels and IgG avidity test. One hundred and seventeen patients with ocular toxoplasmosis (OT) who referred to the Farabi Eye Hospital, Tehran, Iran were included in this study. Of the patients, 77 cases were positive for anti-T. gondii IgG, and 8 cases were positive for anti-T. gondii IgM. IgG avidity test revealed 11, 4, and 102 cases were low, intermediate, and high, respectively, and 6.8% and 9.4% of cases were positive for IgM and IgG avidity tests, respectively (P=0.632). Agreement (Kappa value) between paired tests IgG-IgM, IgG-IgG avidity, and IgM-IgG avidity was 0.080, 0.099, and 0.721, respectively (P < 0.05). This study showed that conventional serologic tests (IgM and IgG levels) and IgG avidity correlate well each other and can be used to differentiate recent infections from old OT. It seems that reactivated old infections rather than recently acquired infections are majority of Iranian OT patients.

Keyword

Toxoplasma gondii; IgG; IgM; IgG avidity; ocular toxoplasmosis

MeSH Terms

Antibodies*
Diagnosis*
Humans
Immunoglobulin G*
Immunoglobulin M*
Iran
Prospective Studies
Serologic Tests*
Toxoplasma
Toxoplasmosis, Ocular*
Antibodies
Immunoglobulin G
Immunoglobulin M