SEVA TB ELISA
( Under Field Study )
Dear Sir/Madam,
Thank you for your interest in our “SEVA TB
ELISA” for immunodiagnosis of suspected tuberculosis patients. The following
are the principles and implications of this system brief.
1.
SEVA TB ELISA is based on the
detection of IgG antibody to purify M.tb. H37Ra cocktail Ag ( ES-31,
ES-43, EST-6 Ag) antigen by Indirect ELISA &/ or tubercular antigen
detection against affinity purified anti M.tb. ES31, ES-43, EST-6 antibody by
Sandwich ELISA.
2.
Presence of IgG antibody ( titre of
1:600 and above) against SEVA TB cocktail Ag antigen suggests tuberculosis
infection. Sensitivity and Specificity of the tests are more than 90% compared
to sputum AFB positivity of samples tested. The test is quite helpful in
childhood tuberculosis where it is difficult to get sputum and in clinically
suspected tuberculosis cases negative for AFB smear and culture examination. The
test is also helpful in confirming tuberculosis aetiology in extrapulmonary
tuberculosis (lymphnode Tb, meninges-CNS Tb, genitourinary Tb etc.). Positive
reaction may be observed in other mycobacterial infections and in chronic
obstruction or/ airway diseases. The test results may be used as a complement to
other information available to the clinician.
References:
1)
Bhaskar et al., Ann Trop Paed
1994, 14:25
2)
Nair ER et al., Scand J Infect Dis 2000; 32: 551-556.
3)
Sonika Gupta et al., Current Science; 88(11), 1825-1827.
4)
B.C. Harinath et al., (
Diagnostic Microbiology and Infectious Diseases) in press.
Collection of
blood samples:
5ml of fresh venous blood (or 2ml serum) in
plain sterile vial or finger prick sample on filter paper to be sent to this
department for TB test along with clinical details as given overleaf.
Handling charges for the test:
Rs. 80/- per specimen to be paid
by crossed D.D. in the name of “JBTDRC,
Sevagram” payable at any nationalized Bank in Sevagram/ Wardha.
Collection of
blood sample on filter paper:
Blood
specimen collected at any time of the day can be used in the test. Collect
patient’s finger prick blood ( 20 ml or one drop ) in each of the two circles ( covering the
entire area of the circle) of one filter paper. Similarly collect blood from a
healthy normal person on the second filter paper. Label the filter paper and
send to this department by post for laboratory analysis at the earliest ( within
7 days).
Director
JB
Tropical Disease Research Centre
MGIMS, Sevagram - 442 102