Dot-ELISA vs. PCR of fine needle aspirates of tuberculous lymphadenitis: a prospective study in India.
OBJECTIVE
To evaluate an in-house dot-enzyme-linked immunosorbent assay (ELISA) for confirmation of clinically suspected cases of tuberculous lymphadenitis (TBLN).


METHODS
The study was performed at the postgraduate departments of microbiology and pathology of a tertiary-care teaching hospital in India. Suspected cases of TBLN were prospectively enrolled. Fine needle aspiration was done of enlarged lymph nodes in all patients, and 2 smears were prepared, 1 for acid-fast bacillus (AFB) demonstration and the other for cytologic examination. The remaining material was tested with in-house dot-ELISA and by IS6110 amplification with polymerase chain reaction (PCR), for diagnosis of TBLN.


RESULTS
ELISA was more sensitive and detected 93.2% of cases. PCR and fine needle aspiration cytology (FNAC) detected 82.5% and 61.0% cases, respectively. AFB positivity was 33.1%.


CONCLUSIONS
Application of dot-ELISA was more sensitive but less specific as compared to PCR. PCR, though expensive, should be used in problem cases because of its high specificity.
Jain
Amita
A
Department of Microbiology, K. G. Medical University, Lucknow, UP, India. amita602002@yahoo.com
Verma
Raj Kumar
RK
Tiwari
Vandana
V
Goel
Madhu Mati
MM
D000293:Adolescent; D000328:Adult; D000368:Aged; D000369:Aged, 80 and over; D044963:Biopsy, Fine-Needle; D002648:Child; D002675:Child, Preschool; D003906:Developing Countries; D004797:Enzyme-Linked Immunosorbent Assay; D006801:Humans; D007194:India / Q000453:epidemiology; D008199:Lymphadenitis / Q000382:microbiology / Q000473:pathology*; D008875:Middle Aged; D009169:Mycobacterium tuberculosis / Q000302:isolation & purification*; D016133:Polymerase Chain Reaction; D011446:Prospective Studies; D012680:Sensitivity and Specificity; D014388:Tuberculosis, Lymph Node / Q000382:microbiology / Q000473:pathology*