Akihiko Wada

Comparison of the sensitivity and specificity of two whole blood interferon-gamma assays for M. tuberculosis infection

OBJECTIVESnTo compare the sensitivity and the specificity of the QuantiFERON-TB Gold (QFT-G) and QuantiFERON-TB Gold In Tube (QFT-GIT) diagnostic tests for Mycobacterium tuberculosis infection.nnnMETHODSnOne-hundred patients with culture and/or PCR confirmed M. tuberculosis infection and 168 volunteers with no risk factors for M. tuberculosis infection were tested to estimate sensitivity and specificity, respectively.nnnRESULTSnAnalysis of data from the tuberculosis (TB) patients with valid results found the sensitivity of QFT-GIT (92.6%, 87/94) to be significantly higher than that for the QFT-G test (81.4%, 79/97; p=0.023). The specificity of both QFT-GIT and QFT-G was 98.8% (CI: 95.1%-99.8%) with 2 of the 160 low risk subjects with valid results for both tests being positive. Data analysis confirmed the manufacturers recommended test cut-off as being optimal, but identified higher sensitivity could be obtained by using a lower cut-off, with only a moderate decrease in specificity.nnnCONCLUSIONSnThe QFT-GIT test had enhanced sensitivity for detection of M. tuberculosis infection over the QFT-G test, whilst maintaining equivalent high specificity. The logistic benefits of the QFT-GIT test format, as well as its higher sensitivity, should enable enhanced TB control.

Predictor of success in endobronchial occlusion therapy against intractable pneumothoraces

Background: An increasing number of patients have been receiving bronchial occlusion therapies against spontaneous pneumothoraces. However, predicting which patients will benefit from the procedures remains difficult. Methods: This post-hoc analysis used data from a randomized controlled trial of the Endobronchial Watanabe Spigot (EWS) ®and fibrin glue in patients with intractable pneumothoraces. All of the patients received one or more bronchial occlusion therapies (BOTs). The success of the BOT was defined as the termination of air-leakage from the chest tubes and expansion of the affected lungs within a week of the first or second BOT. Results: The study included 22 patients (male/female: 18/4) with a median age of 68 at the initial BOT. The BOT produced the desired outcome in 13 patients. Univariate analysis suggested that a previous history of pneumothoraces and the absence of a history of heavy cigarette smoking, defined as 40 packs per year or more, are predictors of a favorable therapeutic outcome (p=0.046, 0.067). Multivariate analysis demonstrated that the absence of a history of heavy cigarette smoking significantly correlated with a favorable outcome (p=0.043). Conclusion: The results suggested that spontaneous pneumothorax patients without a history of heavy cigarette smoking may benefit from bronchial occlusion therapies using the EWS, or fibrin glue.