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Two commercial
ELISA tests had very different performance characteristics when used
to test pediatric sera for HSV antibodies.
Performance of two commercial
glycoprotein G-based enzyme immunoassays for detecting antibodies to
herpes simplex viruses 1 and 2 in children and young adolescents.
Leach CT, Ashley RL, Baillargeon J, Jenson
HB.
Clin Diag Lab Immunol. 2002;9:1124-1125
Summary:
Question
What is the accuracy of two commercial enzyme-linked immunosorbent assays
(ELISAs) for the detection of HSV-1 and 2 antibodies in blood samples from
children and adolescents?
Design
The results of two commercial ELISA assays that detect and distinguish
HSV-1 from HSV-2 antibodies on the basis of type-specific antigens of
glycoprotein G-1 (gG-1) and G-2 (gG-2), respectively, were compared to
those obtained by western blotting performed on sera collected from
children and adolescents.
Participants
Healthy children from southern Texas (n = 61; mean age, 7.4 years; range,
1 to 13 years) and pediatric patients referred to the University of
Washington for HSV type-specific serology (n = 128; mean age, 5.7 years;
range, 1 to 13 years) were tested.
Description of Tests and Diagnostic
Standard
Sixty-one sera were tested with an ELISA assay from Gull Laboratories
(Salt Lake City, UT) that was sold by Meridian Diagnostics (Cincinnati,
OH), and 128 sera were tested with the HerpeSelect HSV-1 and HSV-2 ELISA
(Focus Technologies, Cypress, CA). Both assays use type-specific antigens
of gG-1 and gG-2 to distinguish HSV-1 from HSV-2 antibodies. The
Gull/Meridian assay uses immunoaffinity-purified antigens, while the
HerpeSelect uses antigens based on baculovirus recombinant gG-1 and gG-2.
All sera were tested by standard HSV-1 and HSV-2 western blot assays.
Main Outcome Measures
The sensitivity, specificity, positive predictive value (PPV), and
negative predictive value (NPV) of each ELISA assay compared to the
western blot assay for the detection of HSV-1 and HSV-2 antibodies were
determined.
Main Results
The performance of the two ELISAs compared to western blot for detection
of HSV-1 and HSV-2 antibodies in pediatric patients in shown in the table.
The seroprevalence of HSV-1 by western blot in the samples from Texas was
49%, no samples were HSV-2 positive. Of the sera from the University of
Washington, 36% were seropositive for HSV-1 and 6% for HSV-2 by western
blot. The performance of the HerpeSelect assay was based on 123 sera
because 5 had equivocal results (2 by HerpeSelect HSV-2 and 3 by western
blot). The Gull/Meridian had very low specificity and PPVs, especially for
HSV-2. The HerpeSelect had high specificity for both HSV-1 and HSV-2,
however, the sensitivity for HSV-1 was low.
| Concordance among 57
laboratories testing panel 2 samples |
| Virus |
ELISA |
Sensitivity
(%) |
Specificity
(%) |
PPV (%) |
NPV (%) |
| HSV-1 |
Gull/Meridian |
100 |
74.2 |
78.9 |
100 |
| HerpeSelect |
80 |
97.4 |
95 |
89 |
| HSV-2 |
Gull/Meridian |
Indeterminate |
47.5 |
0 |
100 |
| HerpeSelect |
87.5 |
100 |
100 |
99 |
Authors' Conclusions
The two ELISAs had very different
performance characteristics with pediatric sera. The accuracy of HSV
serologic testing for children appears questionable with current ELISAs,
and a serologic diagnosis of HSV infection should be made with caution. A
negative test should be followed by testing in 6 to 8 weeks to detect
seroconversion, and positive results for HSV-2 antibodies should be
confirmed by a second type-specific test.
Source of funding: Public Health
Service grants from the National Institute of Allergy and Infectious
Diseases.
For correspondence: Charles T. Leach,
Department of Pediatrics, Mail Stop 7811, The University of Texas Health
Science Center at San Antonio, 7703 Floyd Curl Dr., San Antonio, TX
78229-3900. E-mail address: leachc@uthscsa.edu.
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