Accuracy of the serological ELISA test compared with the polymerase chain reaction for the diagnosis of cytomegalovirus infection in pregnancy.
BACKGROUND
The most frequently used methods for detecting antibodies are the indirect immunofluorescence test and the enzymatic immunoassay (ELISA). The polymerase chain reaction is a molecular biology technique in which the production of large amounts of specific DNA fragments is induced from very low concentrations of complex substrates aloowing the detection of very low amounts of viral particles.


OBJECTIVE
To assess the accuracy of serological/ELISA tests in comparison with the polymerase chain reaction in maternal blood to diagnose cytomegalovirus infection.


METHODS
A descriptive study was performed.


METHODS
High-risk outpatient clinic of Campinas University (Unicamp).


METHODS
We selected 243 pregnant women. All of them had been indicated for blood sampling because of suspicions of cytomegalovirus infection and also because of other infections.


METHODS
The group was tested for cytomegalovirus. Serological tests were run and compared to the polymerase chain reaction, which was considered to be the gold standard. Status analyses were done using Fisher's exact test, via the SAS software.


RESULTS
The previous cytomegalovirus infection rate was 94.6%. The main reasons for inclusion in the study were fetal nervous system malformation (25.5%), maternal toxoplasmosis (25.5%) and Rh isoimmunization (14.8%). Only two women were included because of positive serological immunoglobulin M test for cytomegalovirus. The sensitivity and specificity of the serological tests were 94% and 6% for immunoglobulin G.


CONCLUSIONS
Serological tests had lower sensitivity in comparison with the polymerase chain reaction test when diagnosing cytomegalovirus infection. The consequences of positive polymerase chain reaction and negative immunoglobulin M in women remain unknown.
Parmigiani
Silvana Varella
SV
Department of Gynecology and Obstetrics, Faculdade de Ciências Médicas, Universidade Estadual de Campinas, Campinas, São Paulo, Brazil. aparmigiani@aol.com
Barini
Ricardo
R
Costa
Sandra Cecília Botelho
SC
Amaral
Eliana
E
da Silva
José Carlos Gama
JC
Pinto e Silva
João Luiz de Carvalho
JL
D000328:Adult; D003586:Cytomegalovirus Infections / Q000097:blood / Q000175:diagnosis* / Q000276:immunology; D004797:Enzyme-Linked Immunosorbent Assay / Q000379:methods; D005260:Female; D006801:Humans; D007074:Immunoglobulin G / Q000032:analysis; D007075:Immunoglobulin M / Q000032:analysis; D016133:Polymerase Chain Reaction / Q000379:methods; D011247:Pregnancy; D011251:Pregnancy Complications, Infectious / Q000097:blood / Q000175:diagnosis* / Q000276:immunology; D012698:Serologic Tests
D007074:Immunoglobulin G; D007075:Immunoglobulin M