All-cause 8-week mortality is reduced by rapid point-of-care urine-based testing for tuberculosis (TB), using a test for detection of mycobacterial lipoarabinomannan (LAM) to guide rapid treatment initiation in hospitalised HIV-positive people with signs and symptoms of TB, according to a late-breaker study presented by Dr Jonny Peter of the University of Cape Town, and colleagues, at the 46th Union World Conference on Lung Health in Cape Town from 2 to 6 December 2015.
Those who received LAM testing in addition to standard of care diagnostics were 18% less likely to die at 8 weeks (aHR = 0.82; 95% CI: 0.70-0.96, p = 0.015).
The LAM strip test measures for the presence of lipoarabinomannan in urine. The test has shown variable sensitivity and specificity in different populations, and has performed best in studies of hospitalised patients with HIV infection and advanced immunosuppression (CD4 count below 150 cells/mm3). The test is not considered suitable for outpatient screening. (Lawn 2012)
Speeding up diagnosis by using a point-of-care test in addition to laboratory diagnostic tests such as TB culture or Xpert MTB/RIF has the potential to speed up the initiation of treatment and to increase the number of people receiving treatment.
The randomised controlled trial studied whether the LAM strip test, in combination with current available TB diagnostics, would improve TB-related mortality, morbidity and length of hospital stay in HIV-positive people. TB mortality is high, especially in people living with HIV with extensive immune damage, where a TB diagnosis is already difficult.
The study was conducted in South Africa, Tanzania, Zambia and Zimbabwe.