Chaisson LH, et al. - Experts assessed the implementation and effect of a molecular testing strategy to guide discontinuation of isolation for patients with possible tuberculosis (TB) in a US hospital. Findings suggested safety, feasibility, wide and sustainable implementation, and considerable clinical and economic advantages of a sputum molecular testing algorithm to guide discontinuation of respiratory isolation for patients being evaluated for active TB. In US hospitals, more efficient, patient-centered evaluation may be enabled by molecular testing for possible TB.

Methods

• Authors conducted a prospective cohort study with a pragmatic, before-and-after-implementation design of 621 consecutive patients hospitalized at Zuckerberg San Francisco General Hospital and Trauma Center who were undergoing sputum examination for evaluation for active pulmonary TB from January 2014 to January 2016.
• Implementation of a sputum molecular testing algorithm using GeneXpert MTB/RIF (Xpert; Cepheid) to guide discontinuation of isolation was included in the interventions.
• The proportion of patients with molecular testing ordered and completed were measured along with the accuracy of the molecular testing algorithm in reference to mycobacterial culture; the duration of each component of the testing and isolation processes; length of stay; mean days in isolation and in hospital; and mean cost.
• Data from hospital records were extracted and measures before and after implementation were assessed.

Results

• During the 2-year study period, clinicians ordered sputum testing for TB for 621 patients at ZSFG.
• Findings suggested that out of 301 patients in the preimplementation period with at least 1 sputum microscopy and culture ordered, clinicians completed the rapid TB testing evaluation process for 233 (77%).
• Among 320 patients evaluated in the postimplementation period, molecular testing for 234 (73%) patients was ordered by clinicians and results were received for 295 of 302 (98%) tests ordered.
• Fifty-four years (interquartile range, 44-63 years) was the median age, and 161 (26%) were women.
• Results demonstrated an accurate diagnosis of all 7 patients by the molecular testing algorithm with culture-confirmed TB and excluded TB in all 251 patients with Mycobacterium tuberculosis (MTB) culture-negative results.
• Relative to the preimplementation period, there were significant decreases in median times to final rapid test result (39.1 vs 22.4 hours, P < .001), discontinuation of isolation (2.9 vs 2.5 days, P=.001), and hospital discharge (6.0 vs 4.9 days, P=.003), with average $13,347 saved per isolated TB-negative patient.