Detection of human immunodeficiency virus infection in the sputum of tuberculosis patients in South India.
METHODS
A DOTS clinic in an academic tertiary referral hospital in South India.


OBJECTIVE
To evaluate the performance of two rapid enzyme-linked immunoassays (EIAs) for the detection of human immunodeficiency virus (HIV) infection in sputum samples of patients with tuberculosis (TB).


METHODS
We prospectively recruited 522 consecutive out-patients presenting to the DOTS clinic with confirmed TB of any type to undergo HIV testing using reference serum EIA and index-blinded parallel sputum HIV testing with two rapid EIAs designed for oral mucosal transudate.


RESULTS
HIV positivity was 14.9% (95%CI 12.1-18.4). Compared to reference serum EIA, the Oraquick™ assay was 93.1% sensitive (95%CI 83.8-97.4) and 95.3% specific (95%CI 92.7-96.9), while the Aware™ assay was 92.3% sensitive (95%CI 83.4-96.8) and 96.6% specific (95%CI 94.4-98.0). The positive predictive values were respectively 77.0% and 82.7%. After freezing of sputum, the sensitivity of both assays declined, but the specificity significantly increased. Higher sputum volume reduced the odds of obtaining a true result with both assays.


CONCLUSIONS
HIV testing of fresh sputum is not sufficiently accurate for anonymous HIV surveillance among TB patients in a setting of low (<10%) HIV prevalence. Freezing sputum samples and limiting sputum volume for HIV testing may improve assay specificity.
Grandin
W
W
Department of Internal Medicine, Brigham and Women's Hospital, Harvard Medical School, Boston, Massachusetts, USA.
Dev
A V
AV
Latha
A
A
Armstrong
L
L
Mathai
D
D
John
K R
KR
Daley
P
P
D000328:Adult; D005260:Female; D006678:HIV / Q000302:isolation & purification*; D015658:HIV Infections / Q000175:diagnosis* / Q000453:epidemiology / Q000821:virology; D006801:Humans; D007124:Immunoenzyme Techniques; D007194:India / Q000453:epidemiology; D016015:Logistic Models; D008297:Male; D008403:Mass Screening / Q000379:methods; D008875:Middle Aged; D009169:Mycobacterium tuberculosis / Q000302:isolation & purification*; D011237:Predictive Value of Tests; D015995:Prevalence; D011446:Prospective Studies; D011933:Reagent Kits, Diagnostic; D012680:Sensitivity and Specificity; D013048:Specimen Handling; D013183:Sputum / Q000382:microbiology* / Q000821:virology*; D014376:Tuberculosis / Q000175:diagnosis* / Q000453:epidemiology / Q000382:microbiology
D011933:Reagent Kits, Diagnostic