Diagnostic value of FeNO and MMEF for predicting cough variant asthma in chronic cough patients with or without allergic rhinitis.

OBJECTIVE: To evaluate the diagnostic value of fractional exhaled nitric oxide (FeNO) and maximum mid-expiratory flow (MMEF) for differentiating cough variant asthma (CVA) from chronic cough in patients with or without allergic rhinitis. METHODS: In total, 328 patients with chronic cough who underwent spirometry and FeNO testing were consecutively included in the retrospective analysis. Patients were divided into the CVA (n = 125) or NCVA (n = 203) groups according to the diagnostic criteria of CVA. Receiver operating characteristic (ROC) curves were established to assess the diagnostic efficiency and optimal cutoff points of FeNO and MMEF for the prediction of CVA. RESULTS: The optimal cutoff values of FeNO and MMEF to discriminate CVA from chronic cough were 24.5 ppb (AUC, 0.765; sensitivity, 69.60%; specificity 72.91%; PPV, 61.27%; NPV, 79.57%) and 66.2% (AUC, 0.771; sensitivity, 67.20%; specificity 78.33%; PPV, 65.63%; NPV, 79.50%). The optimal cutoff values of combining FeNO with MMEF to discriminate CVA from chronic cough were >22 ppb for FeNO and <62.6% for MMEF (AUC, 0.877). In patients with and without allergic rhinitis, the optimal cutoff point of FeNO to discriminate CVA from chronic cough was 24.5 ppb (AUC, 0.820) and 33.5 ppb (AUC, 0.707), respectively. CONCLUSIONS: FeNO and MMEF might have greater value as negative parameters for differentiating CVA from chronic cough. Combining FeNO and MMEF provided a significantly better prediction than either alone. The diagnostic accuracy of FeNO for predicting CVA in chronic cough patients with allergic rhinitis was higher than in chronic cough patients without allergic rhinitis.

[Effect and mechanism of lipopolysaccharides-induced myeloid-derived suppressor cells on airway inflammation in asthmatic mice].

OBJECTIVE: To explore the effect and mechanism of lipopolysaccharides (LPS)-induced CD11b⁺Gr-1⁺ myeloid-derived suppressor cells (MDSCs) on airway inflammation in asthmatic mice. METHODS: A total of 34 female BALB/c mice were selected. Among them, 4 mice received an intraperitoneal injection of LPS for inducing the accumulation of MDSCs. And the MDSCs were separated with CD11b immunomagnetic beads from spleen extract. Another 30 mice were randomly divided into normal control, asthmatic and cell treatment groups. The mice in the asthmatic and cell treatment groups were sensitized with ovalbumin by a combination of intraperitoneal injection and challenges to establish the murine asthmatic model. At Days 14 and 21 post-sensitization, the mice in cell treatment group received an intravenous injection of LPS-induced MDSCs. At 24 hours after the last allergen challenge, the number of inflammatory cells were counted and morphological identification of leucocytes in bronchoalveolar lavage fluid (BALF) was performed to analyze the degree of airway inflammation in conjunctions with pathological sections. The BALF and serum levels of interleukin-13 were measured by enzyme-linked immunosorbent assay (ELISA). The number of CD4⁺CD25⁺Foxp3⁺ regulatory T cells (Tregs) in peripheral blood was measured by flow cytometry. RESULTS: The total number of cells, the percentage of neutrophils and eosinophils of BALF in the cell treatment group [(17.0 ± 8.3)×104/ml, 11.1% ± 2.0%, 9.8% ± 2.9%] were significantly lower than those in the asthmatic group [(36.0 ± 15.9)×104/ml, 20.8% ± 4.0%, 14.1% ± 4.2%] (P = 0.000, 0.000, 0.011). Compared to the asthmatic group, the BALF and serum levels of IL-13 were significantly lower [(34.7 ± 7.1) vs (105.0 ± 9.0) ng/L, (34.0 ± 4.7) vs (48.1 ± 6.1) ng/L] (both P = 0.000) and the number of CD4⁺CD25⁺Foxp3⁺ regulatory T cells increased in peripheral blood (8.0% ± 1.3% vs 5.1% ± 2.1%, P = 0.002) and airway inflammation was significantly relieved in the cell treatment group. CONCLUSION: LPS-induced MDSCs may improve airway inflammation through up-regulating Tregs in peripheral blood and suppressing Th2 effector function in asthmatic mice.

Pleomorphic adenoma of the trachea: A case report and review of the literature.

BACKGROUND: Pleomorphic adenoma (PA) is the most common benign tumor that occurs in the salivary glands; however, tracheobronchial PA is rarely observed. To the best of our knowledge, fewer than 50 cases have been reported in the literature. We report a 49-year-old woman who had been treated for asthma for 2 years before being diagnosed with PA of the trachea. CASE SUMMARY: A 49-year-old woman was referred to our hospital due to dyspnea upon exertion and chronic cough with wheezing for 2 years. Laboratory tests showed an elevated white blood cell count, absolute neutrophil count, and percentage of neutrophils. A chest computerized tomography scan showed a well-defined, soft-tissue density lesion measuring 2.4 cm × 2.1 cm in the lower trachea. Flexible bronchoscopy revealed that nearly 90% of the tracheal lumen was obstructed. The histopathological and immunohistochemistry features suggested PA of the trachea. Furthermore, we review the characteristics of 29 patients with tracheobronchial PA over the last 30 years. CONCLUSION: Tracheobronchial PA occurs without gender predominance, mostly in the lower or upper trachea, and has a low recurrence rate. The median age at diagnosis is 48 years. The most common symptoms are cough, stridor, dyspnea, and wheezing.

The relationship between steps of 6MWT and COPD severity: a cross-sectional study.

BACKGROUND AND OBJECTIVE: The distance of 6-minute walk test (D6MWT) has been widely used in the assessment of functional status in patients with COPD, while very little attention has been paid to the role of steps of 6-minute walk test (S6MWT). The purpose of this study was to investigate the relationship between S6MWT and other physiologic parameters of COPD. PATIENTS AND METHODS: Seventy patients with stable COPD were enrolled consecutively in this cross-sectional study. Pulmonary function tests, including spirometry, impulse oscillometry (IOS) and the single-breath diffusing capacity of the lungs for carbon monoxide (DLCO), were carried out at rest. Quality of life was assessed by health-related quality of life (HRQoL) questionnaires, including modified Medical Research Council dyspnea scale (mMRC), St George's Respiratory Questionnaire, Chronic Obstructive Pulmonary Disease Assessment Test (CAT) and Clinical Chronic Obstructive Pulmonary Questionnaire. Both steps and distance were measured in the following 6-minute walk test (6MWT). RESULTS: Both S6MWT and D6MWT showed significant correlation with spirometry, IOS, DLCO parameters and HRQoL questionnaires score. Both pre- and post-6MWT inspiratory capacity showed significant correlation with S6MWT (ρ=0.338, P=0.004; ρ=0.359, P=0.002, respectively), whereas did not correlate with D6MWT (ρ=0.145, P=0.230; ρ=0.160, P=0.189, respectively). In stepwise multiple regression analysis, mMRC grade, age and CAT score remained as significant predictors in the final model for D6MWT (adjusted R 2=0.445, P<0.01). DLCO and CAT score remained as significant predictors in the final model for S6MWT (adjusted R 2=0.417, P<0.01). CONCLUSION: S6MWT is efficient in the evaluation of functional status and quality of life in COPD and has significant correlation with various parameters indicating disease severity. Additionally, S6MWT might be better in predicting lung hyperinflation in COPD compared with D6MWT.

[Comparison of functional parameters of small airways between patients with typical asthma and cough-variant asthma].

OBJECTIVE: To compare the functional parameters of the small airways and clinical characteristics between patients with typical asthma (TA) and cough-variant asthma (CVA). METHODS: Forty-three newly diagnosed asthmatic patients were enrolled, including 15 with TA and positive bronchial provocation test [TA BPT(+)], 12 with TA and positive bronchial dilation test [TA BDT(+)] and 16 with CVA, and 27 healthy subjects served as the control group. All the subjects were required to complete data acquisition, asthma control test, asthma control test scale, fractional exhaled nitric oxide, airway resistance and pulmonary function tests, BPT or BDT. RESULTS: The interval from onset to a definite diagnosis of TA BDT(+) was longer than that of TA BPT(+), while that of CVA was the shortest (P=0.022). The pulmonary functional parameters of TA BDT (+) was significantly lower than those of the other 3 groups (P<0.05). MMEF, MEF75, MEF50, and MEF25 in patients with TA BDT(+), TA BPT(+) and CVA were significantly lower than those in the control group (P<0.01). The resonant frequency, respiratory impedance, resistance at 5 Hz, resistance at 20 Hz, and reactance at 5 Hz were significant higher in patients with TA BDT (+) than in the control subjects, while these parameters showed no significant differences among TA BPT (+), CVA and control groups. The airway resistance in TA BPT(+), CVA, and control groups increased after BPT, and the patients with TA BPT(+) showed greater changes in airway resistance than those in CVA and control groups. In CVA patients, FeNO showed a strong positive correlation with respiratory impedance (r=0.523, P=0.038), resistance at 5 Hz (r=0.542, P=0.030), and resistance at 20 Hz (r=0.524, P=0.037), and the airway responsiveness showed a strong positive correlation with resistance at 20 Hz (Rho=-0.512, P=0.043). CONCLUSION: CVA is the early stage of TA, and CVA, TA BPT(+), and TA BDT(+) may represent different stages of asthma. Uncontrolled, prolonged CVA may evolve into TA BPT (+), whose further progression can cause damages of the pulmonary function and small airway function and leads eventually to TA BDT (+).