Efficacy of Induced Sputum for the Diagnosis of Pulmonary Tuberculosis in Adults Unable to Expectorate Sputum / 결핵및호흡기질환

BACKGROUND: Induced sputum (IS) has been used to collect airway secretions in subjects who have inadequate sputum production. The aim of this study was to investigate the efficacy of IS for the diagnosis of pulmonary tuberculosis (PTB) in adults unable to expectorate sputum. METHODS: Medical records of 39 PTB patients who underwent IS due to absence of spontaneous sputum production between January 2011 and March 2014 at a tertiary hospital in South Korea were reviewed. Results of acid fast bacilli smear, Mycobacterium tuberculosis culture and polymerase chain reaction assay for M. tuberculosis (TB-PCR) of IS specimens from these patients were analyzed. Clinical and high-resolution computed tomography (HRCT) characteristics were also analyzed to find characteristics associated with IS culture positivity. RESULTS: Of the 39 IS specimens from PTB patients, 7 (17.9%) were smear positive and 31 (79.5%) were culture positive. Twenty-four IS specimens were tested for TB-PCR and 13 (54.2%) were positive on TB-PCR. Multivariate analysis showed that younger age (p=0.04) and presence of tree-in-bud appearance on HRCT (p=0.03) were independent predictors of IS culture positivity. CONCLUSION: IS is useful for the diagnosis of PTB in adults unable to expectorate sputum. Younger age and tree-in-bud appearance on HRCT were associated with IS culture positivity in these patients.

The levels of nerve growth factor and IL-4 in induced sputum and characteristics of airway inflammation in cough variant asthma / 中华内科杂志

Objective To observe sputum cytology counts, the levels of nerve growth factor (NGF) and IL-4 in cough variant asthma (CVA) patients and the change of their levels after using glucocorticoids combined with β2-adrenergic agonists one month, and to investigate CVA's characteristics of airway inflammation. Methods Totally 36 patients with untreated CVA were selected, as well as 23 healthy controls. Coughed up sputum cells were obtained and HE strained for differential cell counting in each enrolled patient. In induced sputum's supernatant, the levels of NGF and IL-4 were determined by ELISA.Results Before treatment, CVA patients had a median eosinophils (EOS) percentage of 8%, which was significantly higher than that after treatment (2%, P＜0.05) and in healthy control group (1%, P＜0. 001). The levels of NGF and IL-4 in induced sputum of CVA group were (9. 50 ± 1.69) ng/L and (257.37 ± 53.57) ng/L. After treatment, they were (8.78±1.02) ng/L and (228.60 ±52.93)ng/L in CVA group, (6.98±0.69) ng/L and (166.44±24.75) ng/L in healthy control group. The levels of NGF and IL-4 before and after treatment in the CVA group , as compared with the healthy control group, had statistically significant differences (all P＜0.001). In CVA group before and after treatment, the level of NGF and IL-4 paired difference was significant (P＜0.001). The percentage of induced sputum EOS correlated with sputum supernatant concentrations of NGF and IL-4 (P ＜ 0.01). In induced sputum supernatant, the concentrations of NGF and IL-4 were significant correlated (P＜0.01). Conclusions Glucocorticoid joint long-term β2 agonist inhaled treatment significantly reduced NGF, IL-4 and EOS levels and reduced eosinophilic inflammation, which are closely related with the nerve-immune mechanism, NGF as well as IL-4 participated the inflammation. Induced sputum examination is non-invasive, economical,simple, easily accepted by patients, and repeatable, widely used in clinical.