QuantiFERON-TB Gold In-Tube as a Confirmatory Test for Tuberculin Skin Test in Tuberculosis Contact Tracing: A Noninferiority Clinical Trial.

Background: Screening strategies based on interferon-γ release assays in tuberculosis contact tracing may reduce the need for preventive therapy without increasing subsequent active disease. Methods: We conducted an open-label, randomized trial to test the noninferiority of a 2-step strategy with the tuberculin skin test (TST) followed by QuantiFERON-TB Gold In-Tube (QFT-GIT) as a confirmatory test (the TST/QFT arm) to the standard TST-alone strategy (TST arm) for targeting preventive therapy in household contacts of patients with tuberculosis. Participants were followed for 24 months after randomization. The primary endpoint was the development of tuberculosis, with a noninferiority margin of 1.5 percentage points. Results: A total of 871 contacts were randomized. Four contacts in the TST arm and 2 in the TST/QFT arm developed tuberculosis. In the modified intention-to-treat analysis, this accounted for 0.99% in the TST arm and 0.51% in the TST/QFT arm (-0.48% difference; 97.5% confidence interval [CI], -1.86% to 0.90%); in the per-protocol analysis, the corresponding rates were 1.67% and 0.82% in the TST and TST/QFT arms, respectively (-0.85% difference; 97.5% CI, -3.14% to 1.43%). Of the 792 contacts analyzed, 65.3% in the TST arm and 42.2% in the TST/QFT arm were diagnosed with tuberculosis infection (23.1% difference; 95% CI, 16.4% to 30.0%). Conclusions: In low-incidence settings, screening household contacts with the TST and using QFT-GIT as a confirmatory test is not inferior to TST-alone for preventing active tuberculosis, allowing a safe reduction of preventive treatments. Clinical Trials Registration: NCT01223534.

Nasal versus oronasal mask in home mechanical ventilation: the preference of patients as a strategy for choosing the interface.

INTRODUCTION: In home mechanical ventilation (HMV), the mask is a key factor for patient comfort and therapeutic adherence. There is no evidence on the best strategy for choosing the mask in HMV. OBJECTIVE: To explore patient preference when prescribing the mask for HMV treatment and assess its relationship with effectiveness. METHODS: A prospective study with repeated measures in stable patients receiving home nocturnal ventilation. Alternating oronasal mask (ONM) and nasal mask (NM) were tested in day and overnight sessions, with arterial blood gas measured and S(pO(2)) monitored. At the end of each evening session, patients rated interface comfort using a visual analog scale. At 3 months we evaluated adherence and effectiveness of the treatment. RESULTS: Twenty-nine subjects (mean ± SD age 65 ± 13 y, 44% male) completed the study. Initial functional values were P(CO(2)) 57.4 ± 5.2 mm Hg and time with S(pO(2)) < 90% (T90) 81.5 ± 9.5%. Both ONM and NM significantly decreased P(CO(2)) and T90. Over a third (38%) of our subjects preferred ONM, while NM was deemed more comfortable in general. At 3 months, effectiveness and adherence showed no differences between those treated with NM or ONM. CONCLUSIONS: Patient choice is an effective criterion for selecting the interface in HMV treatment.

Nocturnal home pulse oximetry: variability and clinical implications in home mechanical ventilation.

BACKGROUND: Nocturnal home pulse oximetry (NHPO) provides information by measuring a series of variables: time spent with SaO(2) <90% expressed as percentage (T90) or in minutes (Tm90), mean SaO(2) (MnS), and lowest SaO(2) (LwS.) The presence of significant nocturnal desaturation has been proposed as a parameter in decision making with regard to initiating home mechanical ventilation (HMV) or monitoring HMV effectiveness. However, there is limited information on the possible variability of the test, and this could influence the interpretation of results. OBJECTIVES: To explore the variability between 2 consecutive measurements of NHPO and to determine clinical applications in HMV. METHODS: The patients presented diseases susceptible to HMV treatment and were enrolled in stable condition without respiratory failure. NHPO was conducted on 2 consecutive nights. The variables analyzed were: T90, Tm90, Mns, and LwS. The coefficient of variation (CV), a concordance coefficient (CC), and the Bland-Altman method were used in order to explore the variability. RESULTS: We studied 40 cases. Two were excluded, and the remaining 38 were aged 58 ± 16 years (19 males). Eighteen were receiving HMV. CV values exceeded 100% for T90 and Tm90 and were below 5% for MnS and LwS. The CC for T90, Tm90, and LwS showed confidence intervals with lower limits below 0.5, while for MnS the value was 0.88 (0.79-0.93). CONCLUSIONS: There is a wide variability in NHPO recordings for T90, Tm90, and LwS, so a single determination to detect nocturnal desaturation may not be valid for decision making; the parameter with the least interindividual variability and intraindividual variability was MnS.