The patient impact of point-of-care vs. laboratory placement of Xpert(®) MTB/RIF

Abstract

Background: The Xpert(®) MTB/RIF assay can diagnose tuberculosis (TB) rapidly and with great accuracy. The effect of Xpert placement at point of care (POC) vs. at an off-site laboratory on patient management remains unknown.

Design: At a primary care clinic in Johannesburg, South Africa, we compared TB diagnosis and treatment initiation among 1861 individuals evaluated for pulmonary TB using Xpert performed either at POC or offsite.

Results: When Xpert was performed at POC, a higher proportion of Xpert-positive individuals started treatment (95% vs. 87%, P = 0.047) and time to treatment initiation was shorter (median 0 vs. 5 days, P < 0.001). In contrast, among Xpert-negative TB cases, a higher proportion (87% vs. 72%, P = 0.001) started treatment when the sample was sent to the laboratory, with a shorter time to treatment (median 9 vs. 13 days, P = 0.056). While the overall proportion of presumed TB patients starting treatment was independent of Xpert placement, the proportion started based on a bacteriologically confirmed diagnosis was higher when Xpert was performed at POC (73% vs. 58%, P = 0.006).

Conclusions: Placement of Xpert at POC resulted in more Xpert-positive patients receiving treatment, but did not increase the total number of presumed TB patients starting treatment. When samples were sent to a laboratory for Xpert testing, empiric decision making increased.

Conflict of interest statement

Conflicts of interest: none declared.

Figures

Figure

Estimated time to anti-tuberculosis treatment by Xpert status and Xpert placement. A) All patients with a TB diagnosis, regardless of its basis; B) all patients who were Xpert-positive; and C) all patients who were diagnosed with Xpert-negative TB. TB=tuberculosis; IQR=interquartile range; POC=point of care.