Epidemiological and Clinical Characteristics of 217 Cases of COVID-19 in Jiangsu Province, China.

BACKGROUND COVID-19 has become a worldwide epidemic disease and is a public health crisis. We aim to provide evidence for clinical diagnosis and assessment of severity by analyzing patients' clinical data and early laboratory results and exploring the correlation between laboratory results and clinical classification. MATERIAL AND METHODS We enrolled 283 cases of suspected and diagnosed COVID-19 from 16 hospitals in Jiangsu Province from January to April 2020. The routine laboratory blood examinations, T lymphocyte subsets, and biochemical and coagulation function among different populations were contrasted by t test and chi-square (χ²) test. RESULTS Cough, fever, and dyspnea could be helpful to diagnose COVID-19 infection (P<0.05). Patients who were older or had comorbidities tended to become severe and critical cases. Among all the patients, the most obvious abnormal laboratory results were higher neutrophil count, CRP, total bilirubin, BUN, CRE, APTT, PT, and D-dimer, and lower blood platelet and lymphocyte count. CD3⁺ T cell, CD4⁺ T cell, and CD8⁺ T cell counts gradually decreased with exacerbation of the disease (P<0.05). CONCLUSIONS Cough and fever were the most common symptom. Patients with comorbidities were in more serious condition. The detection of inflammatory indexes, coagulation function, lymphocyte subsets, and renal function can help diagnose and assess the severity of COVID-19.

Is carbonic anhydrase inhibition useful as a complementary therapy of Covid-19 infection?

The ongoing Covid-19 is a contagious disease, and it is characterised by different symptoms such as fever, cough, and shortness of breath. Rising concerns about Covid-19 have severely affected the healthcare system in all countries as the Covid-19 outbreak has developed at a rapid rate all around the globe. Intriguing, a clinically used drug, acetazolamide (a specific inhibitor of carbonic anhydrase, CA, EC 4.2.1.1), is used to treat high-altitude pulmonary oedema (HAPE), showing a high degree of clinical similarities with the pulmonary disease caused by Covid-19. In this context, this preliminary study aims to provide insights into some factors affecting the Covid-19 patients, such as hypoxaemia, hypoxia as well as the blood CA activity. We hypothesise that patients with Covid-19 problems could show a dysregulated acid-base status influenced by CA activity. These preliminary results suggest that the use of CA inhibitors as a pharmacological treatment for Covid-19 may be beneficial.

Clinical characteristics of rehospitalized patients with COVID-19 in China.

This study aims to observe the clinical characteristics of recovered patients from Coronavirus Disease 2019 (COVID-19) with positive in reverse transcription-polymerase chain reaction (RT-PCR) or serum antibody. The profile, clinical symptoms, laboratory outcomes, and radiologic assessments were extracted on 11 patients, who tested positive for COVID-19 with RT-PCR or serum antibody after discharged and was admitted to Hubei No. 3 People's Hospital of Jianghan University for a second treatment in March 2020. The average interval time between the first discharge and the second admission measured 16.00 ± 7.14 days, ranging from 6 to 27 days. In the second hospitalization, one patient was positive for RT-PCR and serum antibody immunoglobulin M (IgM)-immunoglobulin G (IgG), five patients were positive for both IgM and IgG but negative for RT-PCR. Three patients were positive for both RT-PCR and IgG but negative for IgM. The main symptoms were cough (54.55%), fever (27.27%), and feeble (27.27%) in the second hospitalization. Compared with the first hospitalization, there were significant decreases in gastrointestinal symptoms (5 vs 0, P = .035), elevated levels of both white blood cell count (P = .036) and lymphocyte count (P = .002), remarkedly decreases in C-reactive protein and serum amyloid A (P < .05) in the second hospitalization. Additionally, six patients' chest computed tomography (CT) exhibited notable improvements in acute exudative lesions. There could be positive results for RT-PCR analysis or serum IgM-IgG in discharged patients, even with mild clinical symptoms, however, their laboratory outcomes and chest CT images would not indicate the on-going development in those patients.

COVID-19 patients' clinical characteristics, discharge rate, and fatality rate of meta-analysis.

The aim of this study was to analyze the clinical data, discharge rate, and fatality rate of COVID-19 patients for clinical help. The clinical data of COVID-19 patients from December 2019 to February 2020 were retrieved from four databases. We statistically analyzed the clinical symptoms and laboratory results of COVID-19 patients and explained the discharge rate and fatality rate with a single-arm meta-analysis. The available data of 1994 patients in 10 literatures were included in our study. The main clinical symptoms of COVID-19 patients were fever (88.5%), cough (68.6%), myalgia or fatigue (35.8%), expectoration (28.2%), and dyspnea (21.9%). Minor symptoms include headache or dizziness (12.1%), diarrhea (4.8%), nausea and vomiting (3.9%). The results of the laboratory showed that the lymphocytopenia (64.5%), increase of C-reactive protein (44.3%), increase of lactic dehydrogenase (28.3%), and leukocytopenia (29.4%) were more common. The results of single-arm meta-analysis showed that the male took a larger percentage in the gender distribution of COVID-19 patients 60% (95% CI [0.54, 0.65]), the discharge rate of COVID-19 patients was 52% (95% CI [0.34,0.70]), and the fatality rate was 5% (95% CI [0.01,0.11]).

Prognostic value of serum amyloid A in patients with COVID-19.

OBJECTIVE: To investigate the prognostic value of serum amyloid A (SAA) in the patients with Corona Virus Disease 2019 (COVID-19). METHODS: The medical data of 89 COVID-19 patients admitted to Renmin Hospital of Wuhan University from January 3, 2020 to February 26, 2020 were collected. Eighty-nine cases were divided into survival group (53 cases) and non-survival group (36 cases) according to the results of 28-day follow-up. The SAA levels of all patients were recorded and compared on 1 day after admission (before treatment) and 3 days, 5 days, and 7 days after treatment. The ROC curve was drawn to analyze the prognosis of patients with COVID-19 by SAA. RESULTS: The difference of comparison of SAA between survival group and non-survival group before treatment was not statistically significant, Z1 = - 1.426, P = 0.154. The Z1 values (Z1 is the Z value of the rank sum test) of the two groups of patients at 3 days, 5 days, and 7 days after treatment were - 5.569, - 6.967, and - 7.542, respectively. The P values were all less than 0.001, and the difference was statistically significant. The ROC curve results showed that SAA has higher sensitivity to the prognostic value of 1 day (before treatment), 3 days, 5 days, and 7 days after treatment, with values of 0.806, 0.972, 0.861, and 0.961, respectively. Compared with SAA on the 7th day and C-reactive protein, leukocyte count, neutrophil count, lymphocyte count, and hemoglobin on the 7th day, the sensitivities were: 96.1%, 83.3%, 88.3%, 83.3%, 67.9%, and 83.0%, respectively, of which SAA has the highest sensitivity. CONCLUSION: SAA can be used as a predictor of the prognosis in patients with COVID-19.

Effect of anti-reflux treatment on gastroesophageal reflux-associated chronic cough: Implications of neurogenic and neutrophilic inflammation.

Objective: Gastroesophageal reflux disease (GERD) is an important cause of chronic cough. Substance P (SP) has been implicated in the pathophysiology of cough. Proton pump inhibitors (PPIs) and prokinetic agents are the current treatment for GER-associated cough. The aim was to evaluate the effects of anti-reflux treatment and its associations with cellular and neurogenic inflammation.Methods: Thirty-seven patients with GER-associated cough suspected based on characteristic symptoms such as heartburn and worsening of cough by phonation and rising were recruited. A PPI, rabeprazole 20 mg daily, and a prokinetic agent, itopride 50 mg t.i.d., were administered for 4 weeks in a prospective, observational manner. Before and after treatment, subjective cough measures [visual analog scale (VAS) and the Japanese version of the Leicester Cough Questionnaire (J-LCQ)], the modified frequency scale for the symptoms of GERD [FSSG, consisting of 2 domains: acid-reflux (AR) and functional dyspepsia symptoms], sputum and plasma SP levels, and sputum cell differentials were examined. Patients with good response to treatment [Δ (decrease of) VAS >15 mm; n = 21) were compared with poor responders (ΔVAS ≤15 mm).Results: Anti-reflux treatment significantly improved the cough VAS, J-LCQ, and AR symptoms, and ΔVAS and ΔAR were significantly correlated. Decreases of plasma and sputum SP levels and sputum neutrophil counts were significantly greater in responders than in poor responders. Both baseline values and post-treatment changes of plasma SP and sputum neutrophils were significantly correlated for all patients.Conclusions: Successful treatment of GER-associated cough may be associated with the attenuation of neurogenic and neutrophilic inflammation.

Long term effect of sulfur mustard exposure on hematologic and respiratory status, a case control study.

The long term effect of sulfur mustard (SM) exposure including, total and differential white blood cells (WBC), hematological parameters, pulmonary function tests (PFT), and respiratory symptoms (RS) in chemical war victims (CWV) exposed to SM 27-30 years ago were examined. Forty-six CWV and 42 control subjects with similar age from the general population were studied. Hematologic parameters, RS including; chest wheezing, night cough, night wheezing and cough, wheezing due to exercise (by Persian questionnaire), and PFT were assessed in all subjects. Total WBC count (p < 0.001), hematocrit, and mean corpuscular volume (MCV) were significantly higher (p < 0.05 and 0.001, respectively) but mean corpuscular hemoglobin concentration (MCHC) and the percent of monocyte were lower in veterans than control group (p < 0.001 and 0.01, respectively). All PFT values were also lower in CWV compared to control subjects (p < 0.001 for all cases). Maximal mid expiratory flow (MMEF) and maximal expiratory flow at 75% of forced vital capacity (MEF75) were the most affected PFT values in CWV and were 50% or lower of predicted values. All CWV reported respiratory symptoms, including; chest wheezing, night cough, night wheezing and cough, and wheezing due to exercise were higher in the veterans compared to control group (p < 0.001 for all cases). Increased total WBC count and RS but reduction in monocyte, MCHC, and PFT values were shown in CWV 27-30 years after exposure to SM. These results indicated profound hematologic (mainly WBC) and pulmonary effect of SM long time after exposure.

WeChat Public Account Use Improves Clinical Control of Cough-Variant Asthma: A Randomized Controlled Trial.

BACKGROUND WeChat is a convenient and popular social medium, and it seems to be an appropriate platform for education and management of patients. This study sought to identify usefulness in clinical control of cough-variant asthma (CVA). MATERIAL AND METHODS A randomized controlled trial was conducted among 80 CVA patients. After being assigned to either the traditional group (TG) or the WeChat group (WG), they received the same inhalation therapy, but patients in WG received additional education and instruction via our public account on the WeChat application. Questionnaires on asthma and chronic cough, data on pulmonary function, blood-related items, follow-up adherence, and Emergency Department (ED) visits were collected at the initial visit and at 3 months. RESULTS A total of 67 participants completed the trial for analysis. FEV1/predicted and FEV1/FVC were significantly increased in WG (p<0.001; p=0.012) after 3 months. PD20-FEV1 was increased in both groups compared with baseline, but more pronounced in WG (p=0.004). ACQ-7 scores were improved in both groups (p=0.024; p<0.001). Participants allocated to WG experienced a greater improvement in AQLQ and LCQ scores, and between-group differences were significant at 3 months (p=0.040; p=0.001). Furthermore, we observed decreases in blood eosinophil count and FeNO in WG (p=0.048; p=0.014), and WG presented better follow-up compliance (p=0.034). CONCLUSIONS Using WeChat as part of treatment and management of CVA can help patients learn about their disease and medications, as well as improve disease control and therapy outcomes.

Does FeNO Predict Clinical Characteristics in Chronic Cough?

PURPOSE: To evaluate whether exhaled nitric oxide measurement can facilitate in the assessment of chronic cough patients based on their airway inflammatory phenotype. METHODS: We have studied consecutive patients attending a specialist cough clinic. 30 patients with high FeNO (> 30 ppb) and 20 patients with low FeNO (< 20 ppb) were recruited. RESULTS: There was a significant correlation between FeNO, B-Eos and sputum eosinophil count (p < 0.001). The number of recorded coughs in 24 h and HARQ scores were significantly (p < 0.05) higher in patients with a low FeNO. In contrast to the high FeNO group (48%), the greater proportion of these patients were women (90%). LCQ scores were worse in the low FeNO group but it was not significant. CONCLUSION: A strong relationship between FeNO, blood eosinophils and sputum eosinophils confirming phenotypic identity was observed. Whether the observed gender disparity accounts for the different cough frequency characteristics is unknown.

Pertussis without apparent cough in a disabled girl with a tracheostomy.

Pertussis is characterized by intense, prolonged coughing in children often followed by a distinctive whooping sound on inspiration. However, the clinical manifestations and natural course of pertussis in disabled children are largely unknown. We experienced a case of pertussis in a disabled girl who had previously undergone a tracheostomy and laryngotracheal separation. She presented with increased tracheal secretions and required hospitalization but did not develop a cough. Pertussis was suspected from the sputum Gram stain, which revealed numerous, short gram-negative rods that did not grow on chocolate agar. A nucleic acid amplification test was positive for Bordetella pertussis and the patient improved on azithromycin. Pertussis may present without its cardinal symptoms in disabled children.

Correlation study of cough variant asthma and mycoplasma pneumonia infection in children.

Cough variant asthma (CVA), as one of bronchitis diseases, features with repeated cough. In clinics, CAV does not show significant abnormal signs, therefore antibiotic therapy can hardly achieve satisfactory treatment effect. With the development of scientific technologies, the correlation between mycoplasma pneumoniae infection and CVA has become a hot research topic in clinics. In clinics, mycoplasma pneumoniae is extensively regarded as major cause for CVA, with complex pathogenic mechanism. The symptoms of CVA is characterized by chronic non abnormal inflammation, normally accompanied with bronchospasm and intestinal infection. Clinical practices show that about 6% of CVA children mainly show continuous cough till midnight during onset period, which is easily to misdiagnosed as bronchitis. Mycoplasma pneumoniae infection is a common disease threatening Children's health in China. With the annual increase of incidence of infantile pneumonia in China, mycoplasma pneumoniae infection has become a major reason leading to the death of child in China. More such mycoplasma pneumoniae infection is a sporadic disease spreading in a small range, and can onset in four seasons, making great impact on living quality and health of children. On this basis, this paper analyzes the correlation between Children's CVA and mycoplasma pneumoniae infection, in the hope of providing valuable reference for clinical treatment.

Cord Blood Soluble CD14 Predicts Wheeze and Prolonged Cough in Young Children: The PATCH Study.

BACKGROUND: Soluble cluster of differentiation 14 (sCD14) plays a role in the development and manifestation of atopic symptoms, although the results of previous studies have been inconclusive. The aim of this study is to evaluate the practical use of sCD14 as a predictive biomarker of allergy in young children. METHODS: Children aged 0-1 year from a birth cohort in the Prediction of Allergies in Taiwanese Children (PATCH) study were enrolled. Cord blood sCD14 concentrations were measured. Pediatrician evaluation and questionnaire interviews were performed periodically until 1 year of age to determine the children's allergic and respiratory symptoms. RESULTS: Two hundred and six 1-year-old subjects were enrolled. Wheeze was positively associated with cord blood sCD14, a family member with asthma and parental smoking. Prolonged cough was associated with cord blood sCD14, older maternal age and more siblings. In the multivariate logistic regression analysis, cord blood sCD14 was the only independent predictive biomarker for wheeze and prolonged cough by 1 year of age. Every 100-ng/ml increase in cord blood sCD14 resulted in a 1.56-fold higher risk of developing wheeze and a 1.62-fold higher risk of prolonged cough in children by 1 year of age. CONCLUSIONS: Cord blood sCD14 may be a useful biomarker for predicting infant wheeze and prolonged cough by 1 year of age.

Beware the "red herring".

A young patient with relapsed diffuse large B-cell lymphoma presented with new onset respiratory symptoms and hypereosinophilia in the early stage post high-dose therapy/autologous stem cell rescue. Here, we present a step-wise practical approach to this unexpected laboratory finding for a not uncommon infective complication in the immunosuppressed patient.

A test of vitamin D benefits on respiratory health mediated through inflammatory markers.

Previous studies have shown that vitamin D has beneficial effects on respiratory health. The role of inflammation as a possible mediator between vitamin D and respiratory health is not well understood. We used National Health and Nutrition Examination Survey 2001-2006 data (unweighted N = 12,856) to examine the mediating effects of biomarkers of inflammation on associations between vitamin D and respiratory health. Vitamin D was measured by serum 25 hydroxy vitamin D test. Respiratory health was measured by self-reported respiratory symptoms and chronic obstructive pulmonary disease (COPD). Biomarkers included C-reactive protein (CRP), alkaline phosphatase (AP), and five leukocyte measures. Models controlled for season, age, sex, race/ethnicity, body mass index, and current and former smoking. Lower levels of vitamin D were significantly associated with respiratory symptoms (linear trend p < 0.01) and with COPD (linear trend p < 0.0002) after adjusting for covariates. Adding biomarkers to the models to test for mediation, the vitamin D effect on respiratory health was not a consequence of any single marker but was partially attenuated as a combined result of leukocytes, AP, and CRP. Vitamin D is beneficial to improve respiratory health. Its benefits do not appear to be mediated by any single biomarker examined in this study; rather, benefits of vitamin D may act broadly through multiple mediating mechanisms.

Usefulness of C-reactive protein testing in acute cough/respiratory tract infection: an open cluster-randomized clinical trial with C-reactive protein testing in the intervention group.

BACKGROUND: Point of care testing for C-reactive protein (CRP) has shown promise as a measure to reduce unnecessary antibiotic prescribing in respiratory tract infections (RTI), but its use in primary care is still controversial. We aimed to evaluate the effect of CRP testing on the prescription of antibiotics, referral for radiography, and the outcome of patients in general practice with acute cough/RTI. METHODS: An open-cluster randomized clinical trial was conducted, with CRP testing performed in the intervention group. Antibiotic prescribing and referral for radiography were the main outcome measures. RESULTS: A total of 179 patients were included: 101 in the intervention group and 78 in the control group. The two groups were similar in clinical characteristics. In the intervention group, the antibiotic prescribing rate was 37.6%, which was significantly lower than that in the control group (58.9%) (P=0.006). Referral for chest X-ray was also significantly lower in the intervention group (55.4%) than in the control group (75.6%) (P=0.004). The recovery rate, as recorded by the GPs, was 92.9% and 93.6% in the intervention and control groups, respectively. CONCLUSION: The study showed that CRP testing in patients with acute cough/RTI may reduce antibiotic prescribing and referral for radiography, probably without compromising recovery. TRIAL REGISTRATION: The trial was registered in the ClinicalTrials.gov Protocol Registration System (identification number: NCT01794819).

Dry night cough as a marker of allergy in preschool children: the PARIS birth cohort.

BACKGROUND: Early detection of children at risk for developing allergy is an important challenge. Our first analyses in infants from the Pollution and Asthma Risk: an Infant Study (PARIS) birth cohort suggested that dry night cough was associated with parental-reported allergic disorders. The aim of the present study was to refine this finding by investigating the time course of dry night cough from birth to age 4 yr in relation to blood markers of atopy and allergic morbidity. METHODS: Health outcomes were regularly assessed by parental self-administered questionnaires. Blood markers of atopy were measured at age 18 months. Children with similar patterns of dry night cough over the first 4 yr of life were grouped together using k-means clustering. Associations with atopy/allergy were studied using multinomial logistic regression. RESULTS: Three trajectories of dry night cough were identified in 1869 children. Besides the never/infrequent pattern (72.4%), the transient pattern (8.8%) was composed of children who coughed in the first year and recovered by age 4 yr, while the rising pattern (18.8%) included all symptomatic children at age 4 yr, whether they were persistent or late coughers. Compared with the never/infrequent pattern, the rising pattern was significantly associated with elevated total immunoglobulin E (IgE) level (odds ratio [OR] = 1.70, 95% confidence interval [CI] = 1.21-2.39) and inhalant allergens sensitization (OR = 2.66, 95% CI = 1.26-5.61) at age 18 months, and with doctor-diagnosed allergic diseases over the first 4 yr such as hay fever (OR = 2.52, 95% CI = 1.49-4.26) and eczema (OR = 1.29, 95% CI = 1.00-1.66). CONCLUSIONS: This study provides evidence that persistent/late dry night cough may indicate allergy in preschool children.

Sensitization profile in differential diagnosis: allergic asthma vs. chronic (nonspecific) cough syndrome.

BACKGROUND: In the subgroup of children with chronic cough, distinguishing children with allergic asthma from those with non-specific respiratory symptoms is difficult. We have focused on determination of diagnostic efficiency of serum total IgE, sIgE, and skin prick test in differentiation of asthmatic children from children with nonspecific respiratory symptoms. MATERIAL AND METHODS: A total of 131 children with median age of 7.5 years were enrolled in study and divided into 2 groups; children with allergic asthma (N=71) and children with chronic cough (N=60). Participants underwent the standard allergological examination, including skin prick test and measurement of total IgE, and following 3 allergen-specific IgE antibodies against aeroallergens: Dermatophagoides pteronyssinus, Ambrosia artemisiifolia, and Phleum pratense. RESULTS: The percentage of patients with elevated level of total and sIgE was higher in children with allergic asthma than in children with chronic cough syndrome (P=0.0001). In children with asthma, sIgE had a better diagnostic value than total IgE. The best diagnostic efficiency of cut-off values for sIgE was shown for Der p sIgE. Skin prick test to all allergens had 78.82% sensitivity and 91.3% specificity in differentiating the 2 tested groups. The highest sensitivity and specificity in skin prick test was proved for Dermatophagoides pteronyssinus. CONCLUSIONS: The sensitization profile consisting of total IgE, sIgE levels, and SPT clearly distinguishes children with allergic asthma from children with chronic nonspecific cough, but still with overlap. Therefore, diagnosis should always be confirmed by a thorough allergy investigation.

Immunoglobulin signature predicts risk of post-acute COVID-19 syndrome.

Following acute infection with severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) a significant proportion of individuals develop prolonged symptoms, a serious condition termed post-acute coronavirus disease 2019 (COVID-19) syndrome (PACS) or long COVID. Predictors of PACS are needed. In a prospective multicentric cohort study of 215 individuals, we study COVID-19 patients during primary infection and up to one year later, compared to healthy subjects. We discover an immunoglobulin (Ig) signature, based on total IgM and IgG3 levels, which - combined with age, history of asthma bronchiale, and five symptoms during primary infection - is able to predict the risk of PACS independently of timepoint of blood sampling. We validate the score in an independent cohort of 395 individuals with COVID-19. Our results highlight the benefit of measuring Igs for the early identification of patients at high risk for PACS, which facilitates the study of targeted treatment and pathomechanisms of PACS.

Plasma substance P levels in patients with persistent cough.

BACKGROUND: Substance P (SP) is involved in the pathogenesis of cough in animal models. However, few studies in humans have been reported and the roles of SP in clinical cough remain obscure. OBJECTIVES: To clarify the relevance of plasma levels of SP in patients with persistent cough. METHODS: We studied 82 patients with cough persisting for at least 3 weeks and 15 healthy controls. Patients were classified as having asthmatic cough (cough-variant asthma and cough-predominant asthma; n = 61) or nonasthmatic cough (n = 21; postinfectious cough, n = 6; gastroesophageal reflux disease, n = 5; idiopathic cough, n = 5, and others, n = 5). Correlations were evaluated between plasma SP levels as measured with ELISA and methacholine airway hyperresponsiveness (airway sensitivity and airway reactivity), capsaicin cough sensitivity, sputum eosinophil and neutrophil counts, and pulmonary function. RESULTS: Plasma SP levels were significantly elevated in patients with both asthmatic and nonasthmatic cough compared with controls [31.1 pg/ml (range 18.0-52.2) and 30.0 pg/ml (range 15.1-50.3) vs. 15.4 pg/ml (range 11.3-23.7); p = 0.003 and p = 0.038, respectively] but did not differ between the two patient groups (p = 0.90). Plasma SP levels correlated with airway sensitivity (threshold dose of methacholine) in the patients with asthmatic cough (r = -0.37, p = 0.005) but not with airway reactivity, cough sensitivity, FEV1 values, or sputum eosinophil and neutrophil counts in either group. CONCLUSIONS: Increased levels of SP in plasma are associated with persistent cough in humans and might be related to airway sensitivity in asthmatic cough.

Diagnostic Value of Fractional Exhaled Nitric Oxide and Small Airway Function in Differentiating Cough-Variant Asthma from Typical Asthma.

Purpose: To explore the diagnostic value of fractional exhaled nitric oxide (FeNO), small airway function, and a combined of both in differentiating cough-variant asthma (CVA) from typical asthma (TA). Methods: A total of 206 asthma subjects, including 104 CVA and 102 TA, were tested for pulmonary function, bronchial provocation test and FeNO. The correlation between FeNO, small airway function and other pulmonary indicators was analyzed by single correlation and multiple regression analysis. The receiver operating characteristic (ROC) curve was established to evaluate the diagnostic efficiency of FeNO, small airway function, and their combination and to predict the optimal cut-off point. Results: All the respiratory function parameters and small airway function indicators in TA group were significantly different from those in CVA group, and FeNO value was significantly higher than that in CVA group. In addition, the area under the ROC curve (AUC) was estimated to be 0.660 for FeNO, 0.895 for MMEF75%/25%, 0.873 for FEF50%, 0.898 for FEF25%, 0.695 for Fres, 0.650 for R5-R20, and 0.645 for X5. The optimal cut-off points of FeNO, MMEF75%/25%, FEF50%, FEF25%, Fres, R5-R20 and X5, were 48.50 ppb, 60.02%, 63.46%, 45.26%, 16.63 Hz, 0.38 kPa·L-1·s-1, and -1.32, respectively. And the AUC of FeNO combined with small airway function indexes FEF25%, Fres, R5-R20, and X5 were prior than single indicators. Conclusion: FeNO and small airway function indexes might have great diagnostic value for differentiating CVA from TA. The combination of FeNO and FEF25%, Fres, R5-R20, and X5 provided a significantly better prediction than either alone.