Mycopathologia

, Volume 166, Issue 2, pp 77–82

Significance of Isolated Positive IgM Serologic Results by Enzyme Immunoassay for Coccidioidomycosis

  • Janis E. Blair
  • Jeremiah T. Currier
Article

DOI: 10.1007/s11046-008-9129-9

Cite this article as:
Blair, J.E. & Currier, J.T. Mycopathologia (2008) 166: 77. doi:10.1007/s11046-008-9129-9

Abstract

Serologic testing is important for diagnosis of coccidioidomycosis. Many methods are available for diagnostic testing. Enzyme immunoassay (EIA) can be performed quickly and locally but has the potential for false-positive results in patients manifesting a positive EIA for immunoglobulin M (IgM) antibodies and a negative EIA for immunoglobulin G (IgG). We retrospectively reviewed the charts of 405 patients with coccidioidal serologic testing performed between 1999 and 2003. Of 706 EIAs, 37 (5%) produced test results for 28 patients that showed isolated IgM positivity. Among these 28 patients, 24 (86%) had positive serologic findings by other methods (complement fixation or immunodiffusion or both), and 7 (25%) had positive microbiologic or histopathologic findings. All 4 (14%) patients without other positive serologic results had diagnostic tests with positive microbiologic or histopathologic results. No false-positive IgM assays were observed. We conclude that the false-positive rate of the EIA IgM is low, and that an isolated positive EIA IgM should prompt further follow-up and diagnostic testing.

Keywords

CoccidioidesImmunoenzyme techniquesFalse-positive reactionsPredictive value of tests

Abbreviations

ADHS

Arizona Department of Health Services

CF

Complement fixation

EIA

Enzyme immunoassay

HIV

Human immunodeficiency virus

ID

Immunodiffusion

IgG

Immunoglobulin G

IgM

Immunoglobulin M

Copyright information

© Springer Science+Business Media B.V. 2008

Authors and Affiliations

  • Janis E. Blair
    • 1
  • Jeremiah T. Currier
    • 2
  1. 1.Division of Infectious DiseasesMayo ClinicScottsdaleUSA
  2. 2.Northern Arizona UniversityFlagstaffUSA