Tuberc Respir Dis.  1999 Apr;46(4):473-480. 10.4046/trd.1999.46.4.473.

Evaluating the Usefulness of the ICT Tuberculosis Test Kit for the Diagnosis of Tuberculosis

• Chang CH
• Son HC
• Ryu KC
• Park SK
• Lee SH
• Kim SR
• Park KH
• Kim WS
• Koo KS

• KMID: 2050109
• DOI: http://doi.org/10.4046/trd.1999.46.4.473

Abstract

BACKGROUND: Early diagnosis of tuberculosis is critical, especially in Korea, an area where tuberculosis is endemic. Because antibody responses to some membrane proteins of Mycobacterium tuberculosis are not comparable, and the policy of BCG vaccination and the prevalence of tuberculosis are different from country to country, the usefulness of the serological diagnostic tests is questionable in Korea, even though they have been confirmed to be useful in other countries. In the specific context of Korea, we tried to evaluate the validity of the ICT Tuberculosis Test (ICT), a membrane-based antibody kit that purports to detect the 5 M. tuberculosis complex-specific antigens including 38-kDa protein. METHOD: 68 patients with tuberculosis were tested: 37 had no history of previous tuberculosis, and 31 were reactivated cases. The control group comprised 77 subjects: 25 healthy adults, 35 hospital workers with frequent contact with tuberculosis patients, and 17 in-patients with non-tuberculous respiratory diseases.
RESULTS
The diagnostic sensitivities of the ICT were 87% and 73% in patients with versus without previous history of tuberculosis, respectively. The sensitivities of smear-positive and smear-negative patient groups were 81% and 73%, respectively. Both of the two patients with extrapulmonary tuberculosis tested positive through the ICT. The specificities of the ICT were 88%, 94%, and 94% in healthy adults, hospital workers, and non-tuberculous patients, respectively, with an overall specificity of 92%. Conclusion: It is suggested that when combined with traditional techniques, the ICT is an useful tool for the diagnosis of pulmonary tuberculosis. The procedure is simple, easy to perform, rapid, and needs no equipment. It shows 73% sensitivity and 92% specificity for the diagnosis of tuberculosis.

Keyword

Mycobacterium tuberculosis; Serological Diagnosis; 38-kDa Antigen; Diagnostic Sensitivity; ICT

MeSH Terms

Adult
Antibody Formation
Diagnosis*
Diagnostic Tests, Routine
Early Diagnosis
Humans
Korea
Membrane Proteins
Mycobacterium bovis
Mycobacterium tuberculosis
Prevalence
Tuberculosis*
Tuberculosis, Pulmonary
Vaccination
Membrane Proteins