Diagnostic accuracy of a urine lipoarabinomannan test for tuberculosis in hospitalized patients in a High HIV prevalence setting.
BACKGROUND
Effective tuberculosis (TB) control in HIV-prevalent settings is hindered by absence of accurate, rapid TB diagnostic tests. We evaluated the accuracy of a urine lipoarabinomannan (LAM) test for TB diagnosis in South Africa.


METHODS
Hospitalized adults with signs and/or symptoms of active TB were enrolled. Sputum smear microscopy and mycobacterial culture, mycobacterial blood culture, and HIV testing were performed. A spot urine specimen was tested for LAM.


RESULTS
Four hundred ninety nine participants were enrolled; 422 (84.6%) were HIV infected. In microbiologically confirmed TB patients, the LAM test was positive in 114 of 193 [sensitivity 59%, (95% confidence interval: 52 to 66)], including 112 of 167 [67% (59 to 74)] who were HIV infected. Among individuals classified as "not TB", the LAM test was negative in 117 of 122 [specificity 96% (91 to 99)], including 83 of 88 [94% (87 to 98)] who were HIV infected. In confirmed TB patients, the LAM test was more sensitive than sputum smear microscopy (42%, 82 of 193, P < 0.001) and detected 56% (62 of 111) of those who were sputum smear negative. HIV infection [adjusted odds ratio (AOR 13.4)], mycobacteremia (AOR 3.21), and positive sputum smear (AOR 2.42) were risk factors for a positive LAM test.


CONCLUSIONS
The urine LAM test detected a subset of HIV-infected patients with severe TB in whom sputum smear microscopy had suboptimal sensitivity. The combination of urine LAM testing and sputum smear microscopy is attractive for use in settings with high HIV burden.
Shah
Maunank
M
Department of Medicine, Johns Hopkins University Center for Tuberculosis Research, Baltimore, MD 21231, USA.
Variava
Ebrahim
E
Holmes
Charles B
CB
Coppin
Alison
A
Golub
Jonathan E
JE
McCallum
Jeremy
J
Wong
Michelle
M
Luke
Binu
B
Martin
Desmond J
DJ
Chaisson
Richard E
RE
Dorman
Susan E
SE
Martinson
Neil A
NA
D000293:Adolescent; D000328:Adult; D000368:Aged; D001431:Bacteriological Techniques / Q000379:methods; D001769:Blood / Q000382:microbiology; D005260:Female; D015658:HIV Infections / Q000150:complications*; D006761:Hospitals; D006801:Humans; D007297:Inpatients; D008070:Lipopolysaccharides / Q000652:urine*; D008297:Male; D008853:Microscopy / Q000379:methods; D008875:Middle Aged; D012680:Sensitivity and Specificity; D013019:South Africa; D013183:Sputum / Q000382:microbiology; D014376:Tuberculosis / Q000175:diagnosis*; D014556:Urine / Q000737:chemistry*; D055815:Young Adult
D008070:Lipopolysaccharides; C050016:lipoarabinomannan
J Microbiol Methods. 2001 May;45(1):41-52
11295196
Int J Tuberc Lung Dis. 2008 Sep;12(9):1021-9
18713499
J Clin Microbiol. 1992 Sep;30(9):2415-8
1401008
Yonsei Med J. 1990 Dec;31(4):333-8
2127645
Scand J Infect Dis. 2002;34(3):167-71
12030387
Trans R Soc Trop Med Hyg. 2005 Dec;99(12):893-900
16139316
Arch Intern Med. 2003 May 12;163(9):1009-21
12742798
Proc Natl Acad Sci U S A. 1981 May;78(5):3214-7
6789332
Lancet. 1983 Sep 17;2(8351):651-2
6136798
Lancet. 2007 Jun 16;369(9578):2042-2049
17574096
Scand J Infect Dis. 2001;33(4):279-84
11345220
J Clin Microbiol. 1986 May;23(5):901-4
3086370
J Clin Microbiol. 2000 Jun;38(6):2278-83
10834989
AIDS. 2009 Sep 10;23(14):1875-80
20108382