1553. Development of an Improved Antibody Detection EIA for Use in Diagnosis of Coccidioidomycosis.
Session: Poster Abstract Session: Mycology: Diagnostic
Friday, October 28, 2016
Room: Poster Hall
Background: Coccidioidomycosis is a mycoses caused by Coccidioides spp., endemic to the southwestern U.S., northern Mexico and regions of South America. Infections can range from subclinical to life-threatening disease. Serology is the most common technique used for diagnosis, specifically the detection of anti-Coccidioides IgG and IgM antibodies. Here, we present the characteristics of a new antibody detection assay for the diagnosis of coccidioidomycosis, the MVista® Coccidioidesantibody detection EIA (MVD EIA).

Methods: Sera from patients with a coccidioidomycosis diagnosis (n=103), as determined by serology and/or culture followed by confirmatory case review (JM, TZ, CS), and controls (n=220). Samples were diluted and added to microtiter plate wells coated with Coccidioides antigen. Standards and controls containing anti-Coccidioides antibodies were utilized to translate results into EIA units (EU). McNemar’s test was used to compare matched pair test data.

Results: The MVD EIA detected IgG, IgM or either antibody to Coccidioides in 87.4%, 61.2% and 88.3%, respectively, in sera from subjects with coccidioidomycosis. Specificity was determined to be 92.3% for IgG, 96.4% for IgM and 91.8% for both using human control sera. The MVD EIA demonstrated improved sensitivity compared to ID, as both ID and EIA detected 61 cases (59.8%), the EIA detected 29 cases (28.4%), ID detected 2 cases (2.0%) and neither detected 10 cases (9.8%) [McNemar χ2: 21.8, p<0.0001]. Compared to complement fixation (CF), both methods detected 38 cases (61.3%), the EIA detected 20 cases (32.3%), CF detected 2 cases (3.2%) and neither detected 2 cases (3.2%) [p=0.0001]. The MVD EIA also demonstrated improved sensitivity compared to a commercially available EIA, with both assays detecting 61 cases (59.2%), the MVD EIA alone detecting 30 cases (29.1%), the commercial EIA alone detecting 1 case (1.00%) and neither detecting 11 cases (10.6%) [McNemar χ2: 26.3, p<0.0001].

Conclusion: The MVD EIA is sensitive and specific for use with patient sera. The MVD EIA demonstrates improved sensitivity compared to commercial EIAs and traditional serology. The use of this assay has the potential to aid in the diagnosis of coccidioidomycosis by providing increased sensitivity compared to currently available assays, and improved throughput and turnaround time compared to classical serology methods.

Eric D. Holbrook, PhD1, Joshua Malo, MD2, Tirdad Zangeneh, DO3, Christopher Strawter, MD2, Eyal Oren, PhD4, Ian Robey, PhD2, Heidi Erickson, RN5, Racquel Chahal, BS5, Michelle Durkin, MS1, Cynthia Thompson, HSD5, Susan E. Hoover, MD, PhD6, Neil M. Ampel, MD, FIDSA7, L. Joseph Wheat, MD, FIDSA1 and Kenneth Knox, MD3, (1)MiraVista Diagnostics, Indianapolis, IN, (2)University of Arizona College of Medicine, Tucson, AZ, (3)College of Medicine, University of Arizona, Tucson, AZ, (4)University of Arizona College of Public Health, Indianapolis, AZ, (5)University of Arizona, Tucson, AZ, (6)Infectious Diseases, Sanford Health, Sioux Falls, SD, (7)Medicine, University of Arizona College of Medicine, Tucson, AZ

Disclosures:

E. D. Holbrook, MiraVista Diagnostics: Employee , Salary

J. Malo, None

T. Zangeneh, None

C. Strawter, None

E. Oren, None

I. Robey, None

H. Erickson, None

R. Chahal, None

M. Durkin, MiraVista Diagnostics: Employee , Salary

C. Thompson, None

S. E. Hoover, None

N. M. Ampel, None

L. J. Wheat, MiraVista Diagnostics: Owner and director , Owner

K. Knox, None

See more of: Mycology: Diagnostic
See more of: Poster Abstract Session

Findings in the abstracts are embargoed until 12:01 a.m. CDT, Wednesday Oct. 26th with the exception of research findings presented at the IDWeek press conferences.