Korean J Clin Microbiol.  2007 Oct;10(2):123-127.

Evaluation of a Rapid Immunochromatographic Assay Kit for the Diagnosis of Salmonella Typhi Infection

• Lee SM
• Kim YJ
• Hwang SH
• Lee EY
• Son HC
• Chang CL

Abstract

BACKGROUND: Widal test, whose sensitivity and specificity are variable from region to region depending on the incidence of typhoid fever, is still in use and shows a relatively low positive predictive value in Korea. We evaluated a rapid immunochromatographic assay (ICA) kit for the rapid diagnosis of Salmonella Typhi infection.
METHODS
Twenty five patients with Salmonella Typhi bacteremia were selected for the patient group. For the control group, 21 nontyphoidal salmonellosis patients, 56 non-Salmonella bacteremia patients, and 57 healthy individuals were selected for evaluating the specificity of ICA test. Each serum specimen was tested with the SD Salmonella Typhi IgG/IgM kits (Standard Diagnostics, Inc., Yongin, Korea).
RESULTS
The ICA showed a sensitivity of 100% in Salmonella Typhi patients, and specificities of 61.9%, 82.1% and 91.2% in nontyphoidal salmonellosis patients, non-Salmonella bacteremia patients, and healthy individuals, respectively. The ICA test showed a high sensitivity but a low specificity when compared with the Widal test.
CONCLUSION
The ICA test by SD Salmonella Typhi IgG/IgM kit is highly sensitive, but its specificity is relatively low. The ICA test is simple, objective, and suitable for screening typhoid fever.

Keyword

Salmonella Typhi; Immunochromatographic assay; Typhoid fever; Widal test

MeSH Terms

Bacteremia
Diagnosis*
Gyeonggi-do
Humans
Immunochromatography*
Incidence
Korea
Mass Screening
Salmonella Infections
Salmonella typhi*
Salmonella*
Sensitivity and Specificity
Typhoid Fever