Detection of persistent low IgG avidity-an interpretative problem in the diagnosis of acute toxoplasmosis

Result code in IS VaVaI

<a href="https://www.isvavai.cz/riv?ss=detail&h=RIV%2F75010330%3A_____%2F23%3A00014205" target="_blank" >RIV/75010330:_____/23:00014205 - isvavai.cz</a>

Result on the web

<a href="https://journals.plos.org/plosone/article?id=10.1371/journal.pone.0284499" target="_blank" >https://journals.plos.org/plosone/article?id=10.1371/journal.pone.0284499</a>

DOI - Digital Object Identifier

<a href="http://dx.doi.org/10.1371/journal.pone.0284499" target="_blank" >10.1371/journal.pone.0284499</a>

Result language

angličtina

Original language name

Detection of persistent low IgG avidity-an interpretative problem in the diagnosis of acute toxoplasmosis

Original language description

Objectives: For the proper diagnosis of toxoplasmosis it is essential to determine the stage of the infection, for which the most preferred method is IgG avidity test. The avidity index (AI) should initially be low (AI <= 0.3) in the acute phase and increase during the infection. However, persistent low avidity can occur in patients with latent toxoplasmosis, which can complicate the interpretation of the results. The aim of the study is to explain the causes of this phenomenon. MethodologyA retrospective study was carried out with 717 serum samples collected from 442 patients from the categories of pregnant and non-pregnant women, men, and newborns + infants (age < 0.5 year). The trends of AI kinetics were evaluated in repeatedly examined patients. The frequency of cases with low avidity was compared in individual categories of patients and in groups of people with acute and non-acute toxoplasmosis. ResultsThe proportion of patients with initially low avidity was 42.1% in the acute toxoplasmosis group while it was 13.0% in the non-acute groups. In uninfected newborns with anti-Toxoplasma antibodies transmitted from the mother, a decrease in IgG avidity levels over time was observed, resulting in 29.2% of samples showing low (improper) avidity. While the dynamics of IgG avidity and the frequency of cases of improperly low avidity were similar in men and pregnant and non-pregnant women, the category of newborns and infants differed substantially for these indicators. ConclusionsDue to acceptable specificity and negative predictive value, high avidity can rule out acute toxoplasmosis, but moderate sensitivity complicates the possibility of its confirmation. The results of the avidity test must be interpreted in the context of the results of other methods.

Czech name

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Czech description

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Type

J_imp - Article in a specialist periodical, which is included in the Web of Science database

CEP classification

—

OECD FORD branch

30303 - Infectious Diseases

Project

—

Continuities

R - Projekt Ramcoveho programu EK

Publication year

2023

Confidentiality

S - Úplné a pravdivé údaje o projektu nepodléhají ochraně podle zvláštních právních předpisů

Name of the periodical

PLoS One

ISSN

1932-6203

e-ISSN

1932-6203

Volume of the periodical

18

Issue of the periodical within the volume

4

Country of publishing house

US - UNITED STATES

Number of pages

16

Pages from-to

e0284499

UT code for WoS article

000970963500109

EID of the result in the Scopus database

2-s2.0-85152591191