Point-of-care Xpert MTB/RIF tuberculosis testing is associated with more patients getting same-day diagnosis and having same-day treatment initiation but does not result in improved tuberculosis-related morbidity, according to a study published online Oct. 28 in The Lancet.

Grant Theron, Ph.D., from the University of Cape Town in South Africa, and colleagues conducted a multicenter, randomized trial to examine the feasibility, accuracy, and clinical effect of point-of-care Xpert MTB/RIF testing at primary care health care facilities in southern Africa. A total of 758 patients were randomized to receive smear microscopy, and 744 to nurse-performed Xpert MTB/RIF.

The researchers found that there were 182 culture positive patients in the smear microscopy group and 185 culture positive patients in the Xpert MTB/RIF group. At two and six months there were no significant differences between the groups in tuberculosis-related morbidity in culture-positive patients (as measured by TBscore and Karnofsky performance score). Compared with microscopy, sensitivity was higher and specificity similar with point-of-care MTB/RIF. Sensitivity was similar and specificity higher for point-of-care MTB/RIF versus laboratory-based MTB/RIF. More patients in the MTB/RIF group had a same-day diagnosis, same-day treatment initiation, and more culture-positive patients were on treatment by the end of the study, due to reduced dropout.

“The benefits did not translate into lower tuberculosis-related morbidity, partly because of high levels of empirical-evidence-based treatment in smear-negative patients,” the authors write.

Read more Doctors Lounge, 28 October 2013