Article

Rapid detection of early typhoid fever in endemic community children by the TUBEX O9-antibody test.

Laboratory Sciences Division, International Centre for Diarrhoeal Disease Research, GPO Box 128, Dhaka 1000, Bangladesh.
Diagnostic Microbiology and Infectious Disease (impact factor: 2.53). 08/2007; 58(3):275-81. DOI:10.1016/j.diagmicrobio.2007.01.010 pp.275-81
Source: PubMed

ABSTRACT Typhoid remains a global public health problem, and quick accurate immunodiagnosis is needed. Here, we examined the performance of the 5-min TUBEX O9-antibody detection kit in 243 outpatients (mostly children and infants) in their first week of fever and 57 healthy subjects in the Bangladesh community. Based on culture results, TUBEX was 91.2% (31/34) sensitive and 82.3% (172/209) specific in febrile subjects. However, specificity was better in nonfebrile healthy subjects (89.5%, 51/57) or in febrile individuals who serologically had dengue fever (90.5%, 57/63), suggesting that some culture-negative febrile individuals could be truly typhoidal. These individuals were also positive in an anti-crude O9 enzyme-linked immunosorbent assay (ELISA) and the Widal test. Regression analysis of the TUBEX and ELISA results showed good concordance between them, better with the combined IgM-IgG ELISA than with IgM alone, suggesting that TUBEX detects IgM antibodies not necessarily by themselves, as previously reported, but with the help of IgG antibodies.

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Keywords

243 outpatients
 
5-min TUBEX O9-antibody detection kit
 
57 healthy subjects
 
anti-crude O9 enzyme-linked immunosorbent assay
 
Bangladesh community
 
combined IgM-IgG ELISA
 
first week
 
global public health problem
 
IgG antibodies
 
IgM
 
nonfebrile healthy subjects
 
Regression analysis
 
TUBEX detects IgM antibodies
 
Typhoid