Does the use of adjunct urine lipopolysaccharide lipoarabinomannan in HIV-infected hospitalized patients reduce the utilization of healthcare resources? A post hoc analysis of the LAM multi-country randomized controlled trial

Abstract

Background: The World Health Organization (WHO) recommends the use of adjunctive urine lipopolysaccharide lipoarabinomannan (LAM) testing in hospitalized HIV-infected persons with suspected tuberculosis (TB) and a CD4 count <100cells/ml. However, the recommendation is conditional, and uptake by individual treatment programmes depends on perceived additional benefit. The aim of this study was to determine whether adjunctive LAM testing has additional clinical benefits including a reduction in healthcare-related use of resources.

Methods: A post hoc analysis was performed of a published multicentre, multi-country, randomized controlled trial that showed an approximate 20% mortality benefit in HIV-infected hospitalized patients who underwent adjunctive LAM testing as part of their diagnostic workup. In that parent study, adult HIV-infected hospitalized patients with suspected TB (n=2528) were randomly allocated to either routine diagnostics (smear microscopy, Xpert MTB/RIF, and culture; n=1271), or routine diagnostics plus adjunctive urine LAM testing (n=1257). Data were further analyzed to determine whether there were other potential benefits of LAM usage based on CD4 count and illness severity. Aspects evaluated included: (1) the reduction in number of diagnostic sputum samples tested, (2) the utilization of additional imaging, (3) disease resolution based on follow-up signs and symptoms of illness severity, and (4) the reduction in hospital readmission.

Results: Adjuvant LAM did not reduce the number of diagnostic sputum samples requested, the need for additional imaging, or the hospital readmission rate. However, adjunctive LAM was associated with a more rapid rate of disease resolution (dyspnoea) in the severely ill subgroup. Higher LAM grade (grades 4 and 5), compared to lower grade positivity (≤3), was associated with lower use of ultrasound, lower Karnofsky performance score, lower CD4 cell count, and shorter time to culture positivity.

Conclusions: Although, adjunct LAM was associated with a mortality benefit in the parent study, no benefit could be demonstrated in the secondary analysis with respect to the number of diagnostic sputum samples requested, the use of additional imaging, or hospital readmission rates. However, given the limitations of the present study, further appropriately designed studies are required to determine the effect of adjunct urine LAM on the utilization of healthcare resources.

Keywords: HIV-infected; Tuberculosis; Urine lipopolysaccharide lipoarabinomannan.