Rapid assay using recombinase polymerase amplification and lateral flow dipstick for identifying Agrilus mali (Coleoptera: Buprestidae), a serious wood-boring beetle of the western Tianshan Mountains in China.

Agrilus mali stands as a significant wood-boring pest prevalent in Northeast Asia. Identifying this pest beetle is often hindered by insufficient efficient, rapid, on-site discrimination methods beyond examining adult morphological features. As a result, an urgent need arises for developing and implementing a rapid and accurate molecular technique to distinguish and manage the beetle. This study presents a straightforward, swift, highly specific, and sensitive method built upon recombinase polymerase amplification combined with a lateral flow dipstick (RPA-LFD). This method demonstrates the capability to promptly identify the beetle, even during its larval stage. RPA primers and probes were designed using the internal transcribed spacer 1 region. Through probe optimization, false-positive signals were successfully eliminated, with an accompanying discussion on the underlying causes of such signals. The RPA-LFD assays exhibited remarkable specificity and sensitivity, requiring as little as 10-3 ng of purified DNA. Furthermore, the extraction of crude DNA was achieved through immersion in sterile distilled water, thus streamlining the assay process. Achievable at temperatures ranging from 30 to 50 °C, the RPA-LFD assay can be executed manually without specialized equipment. By merging the RPA-LFD assay with DNA coarse extraction, A. mali can be detected within just 30 min. This current study effectively demonstrates the immense potential of RPA-LFD in quarantine and pest management. Additionally, it presents a universal technique for the rapid on-site diagnosis of insects, showcasing the wide applicability of this method.

The complete mitochondrial genome of Platygaster robiniae (Hymenoptera: Platygastridae): A novel tRNA secondary structure, gene rearrangements and phylogenetic implications.

Platygaster robiniae is economically important as a highly specific parasitoid of the invasive pest Obolodiplosis robiniae which was introduced into the Euro-Asia region in the last decade. Despite being a critical and specific parasitoid of the invasive pest O. robiniae and its use as an effective biocontrol agent, the absence of sequence information from P. robiniae have limited its genetic applications for pest management in forests. Mitochondrial (mt) genomes generally contain abundant nucleotide information and thus are helpful for understanding species history. Here, we sequenced the complete mt genome of P. robiniae using next generation sequencing, and annotated 13 protein-coding, 22 tRNA, and 2 rRNA genes and a 702 bp noncoding region. Comparative analysis indicated that this mt genome has a normal A + T content and codons use, however possessed both the expected and unique rearrangements. Ten tRNAs at four gene blocks COII-ATP8, COIII-ND3, ND3-ND5 and the A + T-rich region-ND2 were rearranged, including gene shuffles, transpositions and inversions. Notably, two genes tRNA Ser(UCN) and tRNA Leu(CUN) had undergone long-range inversions, which is the first record of this rearrangement type in the superfamily Platygastroidea. The D-loops of both tRNA Ile and tRNA Leu(CUN) were absent from the tRNA secondary structure, which has not been reported from hymenopteran previously. Phylogenetic analysis based with the maximum likelihood and Bayesian methods showed that P. robiniae grouped with other species of Platygastridae, and that the superfamily Platygastridea is sister to the other Proctotrupomorpha superfamilies. Our tree strongly supports the monophyly of the five superfamilies of Proctotrupomorpha. This study discovered some unique characters of P. robiniae, and contributes to our understanding of genome rearrangements in the order Hymenoptera.

High Expression of MUC5AC, MUC5B, and Layilin Plays an Essential Role in Prediction in the Development of Plastic Bronchitis Caused by MPP.

Plastic bronchitis (PB) is a rare respiratory condition which can result in severe respiratory complications such as respiratory failure and death. Mycoplasma pneumoniae infection is a main etiology cause of plastic bronchitis. However, the pathogenesis of plastic bronchitis complicated by Mycoplasma pneumoniae pneumonia (MPP) has not yet been fully elucidated. Our article aims to explore biomarkers for early prediction of MPP cases complicated with plastic bronchitis. We utilized a protein chip to screen for significantly different proteins among the groups of healthy, general Mycoplasma pneumoniae pneumonia (GMPP) and refractory Mycoplasma pneumoniae pneumonia (RMPP) patients, where layilin exhibited a potent change across biology information technology. Next, we demonstrated the high expression of MUC5AC, MUC5B, and layilin in bronchoalveolar lavage fluid (BALF) of MPP cases complicated with plastic bronchitis. Further study suggested that the level of layilin had a positive correlation with both MUC5AC and MUC5B. A receiver operating characteristic (ROC) analysis was performed to assess the diagnostic values of MUC5AC, MUC5B, and layilin in MPP cases with PB. Data show that the three indicators have similar diagnostic ability for MPP children with plastic bronchitis. Then, we used different concentrations of community-acquired respiratory distress syndrome (CARDS) toxin or lipid-associated membrane proteins (LAMPs) to simulate an in vitro experiment. The in vitro assay revealed that CARDS toxin or LAMPs induced A549 cells to secrete MUC5AC, MUC5B, layilin, and proinflammatory factors. These findings suggest that MUC5AC, MUC5B, and layilin are correlated with MPP. The high expression of MUC5AC, MUC5B, and layilin play an essential role in prediction in the development of plastic bronchitis caused by MPP. The high expression of MUC5AC, MUC5B, and layilin may be relevant to the severity of illness.

Population Genetics Reveals That the Western Tianshan Mountains Populations of Agrilus mali (Coleoptera: Buprestidae) May Have Not been Recently Introduced.

Agrilus mali Matsumura is a wood-boring beetle that aggressively attacks species of the genus Malus, that has recently caused serious damage to the wild apple tree M. sieversii (Lebed.) in the western Tianshan Mountains in Xinjiang. It was first detected there in the early 1990s and spread rapidly, being thus considered a regional invasive pest. To explore the possible outbreak mechanism of the local population and characterize the genetic differentiation of A. mali across different regions of China, we used three mitochondrial genes (COI, COII, and CytB) to investigate the genetic diversity and genetic structure of 17 A. mali populations containing 205 individuals collected from five Chinese provinces. Among them, nine populations were from the western Tianshan Mountains. Ultimately, of the 136 pairwise F st comparisons, 99 showed high genetic differentiation among overall populations, and Tianshan populations exhibited significant differentiation with most of the non-Tianshan populations. Furthermore, A. mali populations represented relatively abundant haplotypes (54 haplotypes). Nine populations from the Tianshan Mountains showed 32 haplotypes (26 of which were unique), displaying relatively high genetic diversity. Additionally, the Mantel test revealed population genetic differentiation among either overall populations or the Tianshan Mountains populations, likely caused by geographical isolation. Phylogenic relationships showed that all populations clustered into three clades, and Tianshan Mountains populations, including CY, occupied one of the three clades. These results suggest that A. mali in the western Tianshan region has possibly been present in the area for a long period, and may not have been introduced recently. Highly frequent gene flows within Tianshan populations are possibly caused by human activities and may enhance the adaptability of A. mali along the western Tianshan Mountains, leading to periodic outbreaks. These findings enhance our understanding of jewel beetle population genetics and provide valuable information for pest management.

The conserved mitochondrial genome of the jewel beetle (Coleoptera: Buprestidae) and its phylogenetic implications for the suborder Polyphaga.

In this study, we sequenced the mitochondrial (mt) genome of Agrilus mali (Coleoptera: Buprestidae) using next-generation sequencing, and accordingly annotated 13 protein-coding, 22 tRNA, and 2 rRNA genes and a 1458-bp non-coding region. Comparative analysis indicated that the mt genome of A. mali is relatively conserved, with a typical gene content and order identical to those of other coleopterans. However, the newly sequenced mt genome is characterized by a relatively higher A + T content compared with that of other species within the family Buprestidae. Phylogenetic analysis based on Bayesian inference revealed that the evolutionary relationship among the six infraorders of the suborder Polyphaga is (Scirtiformia + (Elateriformia + ((Scarabaeiformia + Staphyliniformia) + (Bostrichiformia + (Cucujiformia))))). However, the topology indicated that the family Buprestidae is a sister group to other Polyphaga infraorders, excluding Scirtiformia as a monophyly, and thus the monophyly of Elateriformia was not supported. This study not only presents the mt genome of a species in the family Buprestidae and a comparative analysis of jewel beetles but also examines the contribution of mt genomes in elucidating phylogenetic relationships within the suborder Polyphaga of Coleoptera.

c.753_754delAG, a novel CFTR mutation found in a Chinese patient with cystic fibrosis: A case report and review of the literature.

BACKGROUND: Cystic fibrosis (CF) is rare in Asian populations relative to the Caucasian population. In this paper, we report the cystic fibrosis transmembrane conductance regulator (CFTR) variation in a family of Chinese CF patients, and systematically review the previous literature. CASE SUMMARY: Here we report a 30-month-old Chinese girl who was diagnosed with CF based on her history and symptoms such as recurrent productive cough, wheezing with repeated infection of Pseudomonas aeruginosa, and parasinusitis. Chest computed tomography (CT) scanning revealed obvious exudative lesions and bilateral bronchiectasis. Liver CT scanning revealed a low-density lesion in the left lobe of the liver. A diagnosis of CF was made based upon CFTR gene tests. The CFTR gene was sequenced using the blood samples of her and her parents and showed a heterozygous novel missense mutation of c.753_754delAG in exon 7. In addition, a heterozygous c.1240 C>T mutation was found in exon 10 of the CFTR. The mutation c.753_754delAG was verified to have been inherited from her mother, and the c.1240 C>T mutation was from her father who was diagnosed with congenital absence of vas deferens. CONCLUSION: A novel mutation of CFTR, c.753_754delAG, was found in a Chinese CF child. c.2909G>A is the most common mutation among Chinese CF patients.

Pediatric clinical features of Mycoplasma pneumoniae infection are associated with bacterial P1 genotype.

The present study evaluated the association between different Mycoplasma pneumoniae (M. pneumonia) genotypes and clinical features of pediatric patients. Subjects were children diagnosed with community-acquired pneumonia at the Children's Hospital of Soochow University (Suzhou, China) from January 2012 to December 2013. Clinical and laboratory tests were conducted and clinical samples positive for M. pneumoniae were genotyped by nested-multiplex polymerase chain reaction. Three type I strains and three type II strains were also randomly selected for sequencing. A total of 335 clinical samples positive for M. pneumoniae were obtained. The average age of M. pneumonia-infected pediatric patients was 4.8±3.3 (years). Genotyping results identified 304 positive samples as group I strains and 30 samples as group II strains, in which 1 sample was type II variant 2a. It was also observed that point mutations were more likely to occur in type I strains compared with type II strains. Although clinical pulmonary infection scores between patients with type I and type II strains did not significantly differ, patients with type I strains had a higher risk of developing severe M. pneumoniae pneumonia (SMPP) and extrapulmonary complications, and had significantly higher percentages of peripheral blood neutrophils than patients with type II strains (P<0.05). Collectively, these data indicate that the predominant strains of M. pneumoniae in Suzhou between 2012 and 2013 were type I, and that pediatric pneumonia patients with type I strains of M. pneumoniae were more likely to progress to SMPP.

[Epidemiological analysis of 440 cases of respiratory adenovirus infections in children from the Suzhou area between 2006 and 2015].

OBJECTIVE: To study the epidemiological characteristics of respiratory adenovirus (ADV) infections in children from the Suzhou area, China. METHODS: The clinical data of ADV-positive children out of 35 529 children with respiratory tract infections who were hospitalized in the Children's Hospital of Soochow University between January 2006 and December 2015 were retrospectively studied. RESULTS: Of the 35 529 children with respiratory tract infections, 440 (1.24%) were ADV-positive. There was no significant difference in the rate of ADV infections between boys and girls (1.18% vs 1.34%). The ADV infection rates of children at the age of <1 year old, 1-3 years old, 3-7 years old and 7-14 years old were 0.39% (71/18 002), 1.12% (103/9 191), 3.14% (201/6 398), and 3.35%( 65/1 938) respectively and the rate increased with age (P<0.01). The ADV infection rates in spring [1.85%(60/8 658)] and summer [2.20%(189/8 606)] were significantly higher than in autumn [0.30%(27/8 952)] and winter [0.69%(64/9 313)] (P<0.01). CONCLUSIONS: The ADV infection rate is increased with age in the children from the Suzhou area, but it is not associated with gender. ADV infections are more common in spring and summer.

Prediction of Bronchial Mucus Plugs Formation in Patients with Refractory Mycoplasma Pneumoniae Pneumonia.

Background: We aimed to find the relationship between the clinical characteristics and mucus plug formation and developed models to predict mucus plug formation in refractory Mycoplasma pneumoniae pneumonia (RMPP) infection. Methods: RMPP patients treated with bronchoscopy were retrospectively enrolled in the study between November 2011 and November 2015. Multivariate logistic regression was performed to identify independent predictors of mucus plug formation. Results: Of the 173 RMPP patients enrolled, the mucus plug group accounted for 82 (47.4%) cases. Multivariate logistic regression analysis identified age, fever duration, C-reactive protein (CRP) and lactic dehydrogenase (LDH) as independent risk factors for mucus plug. We assigned one point for age, length of fever and CRP and two points for LDH. Using this predicted score, we identified patients with mucus plug with 71.8% sensitivity and 78.9% specificity. Conclusions: Our predictive models based on demographic and laboratory variables accurately predicted mucus plug formation in initial treatment of patients with RMPP.

Prevalence of rhinovirus in wheezing children: a comparison with respiratory syncytial virus wheezing

Abstract Objective To explore the distribution and clinical manifestations of rhinovirus infection in wheezing children, and compare the clinical differences between rhinovirus- and respiratory syncytial virus-induced wheezing. Materials and methods This prospective cohort study was carried out in Children's Hospital of Soochow University from Dec 2012 to Nov 2014. We enrolled consecutive hospitalized children <60 months of age presented with wheezing. Clinical data including cough, fever, dyspnea, crackles were recorded by pediatricians on the first day of admission. Meanwhile, nasopharyngeal aspirates were obtained to test for respiratory viruses, by using polymerase chain reaction method for rhinovirus, human bocavirus, and human metapneumovirus, and direct immunofluorescence assay to test for respiratory syncytial virus, adenovirus, parainfluenza virus types 1–3, and influenza virus types A and B. Results Rhinovirus was a main causative agent isolated in 14.7% of the hospitalized wheezing children in Suzhou, China, being second to respiratory syncytial virus (21.0%). Different from respiratory syncytial virus infection, which peaked in winter months, rhinovirus could be detected all year round, peaked between July and September, and in November. Children with rhinovirus infection were older and presented with more often allergic sensitizations, blood eosinophilia, and leukocytosis than those of respiratory syncytial virus infection. Logistic regression analysis revealed that rhinovirus-infected children experienced earlier wheezing more often than respiratory syncytial virus children (odds ratio, 3.441; 95% confidence interval, 1.187–9.979; p = 0.023). Conclusion Rhinovirus was a main viral pathogen in wheezing children, especially in summer time. Rhinovirus-induced wheezing was different from respiratory syncytial virus, apart from seasonal epidemics; these two groups differed with regard to age, allergic sensitizations, laboratory test, and history of wheezing episodes.

Prevalence of rhinovirus in wheezing children: a comparison with respiratory syncytial virus wheezing.

OBJECTIVE: To explore the distribution and clinical manifestations of rhinovirus infection in wheezing children, and compare the clinical differences between rhinovirus- and respiratory syncytial virus-induced wheezing. MATERIALS AND METHODS: This prospective cohort study was carried out in Children's Hospital of Soochow University from Dec 2012 to Nov 2014. We enrolled consecutive hospitalized children <60 months of age presented with wheezing. Clinical data including cough, fever, dyspnea, crackles were recorded by pediatricians on the first day of admission. Meanwhile, nasopharyngeal aspirates were obtained to test for respiratory viruses, by using polymerase chain reaction method for rhinovirus, human bocavirus, and human metapneumovirus, and direct immunofluorescence assay to test for respiratory syncytial virus, adenovirus, parainfluenza virus types 1-3, and influenza virus types A and B. RESULTS: Rhinovirus was a main causative agent isolated in 14.7% of the hospitalized wheezing children in Suzhou, China, being second to respiratory syncytial virus (21.0%). Different from respiratory syncytial virus infection, which peaked in winter months, rhinovirus could be detected all year round, peaked between July and September, and in November. Children with rhinovirus infection were older and presented with more often allergic sensitizations, blood eosinophilia, and leukocytosis than those of respiratory syncytial virus infection. Logistic regression analysis revealed that rhinovirus-infected children experienced earlier wheezing more often than respiratory syncytial virus children (odds ratio, 3.441; 95% confidence interval, 1.187-9.979; p=0.023). CONCLUSION: Rhinovirus was a main viral pathogen in wheezing children, especially in summer time. Rhinovirus-induced wheezing was different from respiratory syncytial virus, apart from seasonal epidemics; these two groups differed with regard to age, allergic sensitizations, laboratory test, and history of wheezing episodes.

[The diagnostic value of the fractional exhaled nitric oxide for cough variant asthma in children].

OBJECTIVE: To determine the diagnostic value of fractional exhaled nitric oxide (FeNO) measurement in diagnosis of Cough Variant Asthma (CVA) in children. METHODS: Outpatients with a cough > 4 weeks visiting The Children's Hospital Affiliated to Suzhou University from March 2012 to April 2013 were enrolled. FeNO was measured by a nitric oxide analyzer in accordance with American Thoracic Society guidelines. The levels of FeNO in CVA and other causes of chronic cough were compared. The value of FeNO was assessed and the optimal operating point of FeNO testing for the diagnosis of CVA was determined by the means of the receiver operating characteristic (ROC) curves. RESULTS: A total of 84 children with chronic cough were recruited, among whom 38 were diagnosed as having CVA. The levels of FeNO were not statistically different between patients with CVA [(37.2 ± 13.8) ppb] and patients with CVA combined with upper airway cough syndrome [UACS, (40.1 ± 13.8) ppb, P = 0.124], but were both significantly higher than those in patients with UACS or with postinfectious cough (PIC), and the normal control group (P < 0.01 respectively). There were 46 non-CVA patients, including 34 cases with UACS and 12 PIC, and their FeNO levels were not statistically different [(18.3 ± 7.6) to (19.2 ± 4.4) ppb, t = 2.580, P = 2.996]. The levels of FeNO declined rapidly in CVA patients after inhaled corticosteroids during the 4 week follow-up. The proportion of eosinophils in the sputum from CVA patients was higher than that from the non-CVA patients, consistent with the level of FeNO, which showed a positive linear correlation with sputum eosinophils. The area under ROC curve was 0.94.The optimal diagnostic cutoff point was 22.5 ppb which was capable of differentiating CVA and non-CVA with a sensitivity of 84%, and a specificity of 94.3%. CONCLUSIONS: The level of FENO was higher in CVA compared to other causes of chronic cough. FeNO, a marker of airway eosinophilic inflammation, may be helpful in the diagnosis of CVA in children with high sensitivity and specificity.

Clinical characteristics of protracted bacterial bronchitis in Chinese infants.

Protracted bacterial bronchitis (PBB) is the common cause of chronic cough in children worldwide, but its etiology has not been fully recognized in China. We retrospectively investigated a total of 66 hospitalized infants under the age of three years with chronic wet cough enrolled in the Affiliated Children's Hospital of Soochow University from October 2010 to March 2014. All patients underwent bronchoscopy and broncho-alveolar lavage (BAL) samples were processed for microbiological and cytological analysis. Of 66 patients with wet cough, 50 (75.8%) were diagnosed with PBB. In the PBB group, wet cough was accompanied by wheezing (90%). Airway malacia were identified in 22 cases (44%). The clinical manifestations of PBB with airway malacia did not differ from those without malacia. Haemophilus influenzae (47.4%) and Streptococcus pneumoniae (36.8%) were the most commonly identified pathogens. Furthermore, CD3(+) and CD3(+)CD4(+) cells were significantly lower in the PBB group (p < 0.01), while CD19(+), CD16(+)CD56(+) and CD23(+) cells were elevated (p < 0.01) in the PBB group. Our study revealed PBB is an important cause of chronic wet cough in Chinese infants, and that changes of lymphocyte subsets are observed in children with PBB. Airway malacia frequently co-existed with PBB, but did not exacerbate the disease.

[Characteristics of airway hyperresponsiveness in children with chronic cough of different causes].

OBJECTIVE: To study the characteristics of airway hyperresponsiveness in children with different causes of chronic cough. METHODS: A prospective study was conducted in children suffering from chronic cough caused by a single reason at the department of respirology of Children's Hospital of Soochow University from April 2012 to December 2013. Bronchial provocation test, induced sputum eosinophil count, and exhale nitric oxide were detected at beginning and 4 weeks later. The severity of the CVA was classified according to the integral dose of histamine which resulted in a 20% (PD20) fall in forced expiratory volume in 1 s (FEV1). All patients received treatment according to the recommended guidelines for chronic cough in children of China. According to the responses to the treatment and the results of physical examinations and laboratory findings, a final diagnosis was confirmed. RESULTS: A total of 66 children were enrolled in this study, including cough variant asthma (CVA)in 17, upper airway cough syndrome (UACS) in 37, and post infection cough (PIC) in 12 cases. Positive AHR in CVA, UACS, and PIC groups was found in 17, 13, and 9 cases respectively at the first visit, and after 4 weeks, it was found in 17, 5, and 2 cases respectively. The severity of AHR in CVA, UACS and PIC at beginning and after 4 weeks were moderate to severe in 5, 0, 0 cases and 1, 0, 0 case; Mild to very mild in 12, 13, 9 cases and 16, 5, 2 cases.Negative response was found in 0, 24, 3 cases and 0, 32, 10 cases, respectively. The values of PD20 in CVA group (0.47 ± 0.28) mg were statistically lower those in UACS group (1.8 ± 0.64) mg and PIC group (1.2 ± 0.80) mg (P < 0.01) . The sputum eosinophil count was > 3% in all cases of CVA but all <3% in UACS and PIC.FeNO and sputum eosinophil counts were positively correlated (r = 0.687, P = 0.000) . CONCLUSION: The characteristics of airway responsiveness of chronic cough caused by different causes were varied in different AHR severity and course. Bronchial provocation test combined with induced sputum showed certain values for confirming the cause of chronic cough in children.

[Clinical features of protracted bacterial bronchitis in children].

OBJECTIVE: To analyze the clinical characteristics of protracted bacterial bronchitis (PBB) in children. METHOD: The clinical data of patients seen from October, 2010 to March, 2014 in Department of Respiratory Diseases of our hospital were retrospectively analyzed. Inclusion criteria were over 4 weeks cough, receiving fiberoptic bronchoscopy, positive bacterial culture and (or) the increased percentage of neutral granulocytes in bronchoalveolar lavage fluid (BALF). RESULT: Twenty eight patients were involved, 26 were male (93%) and two were female (7%). The median age of patients was 8.5 months. The median duration of cough was four weeks. The average length of hospital stay was (8.3 ± 3.9)days. The main clinical feature was wet cough in 28 cases, wet cough with wheezing was seen in 21 cases. The wet cough phase distribution was irregular in 21 cases. The crackles with wheeze (in 21 cases) was main signs of PBB. The percentage of CD3⁻ CD16⁺ 56⁺ cells increased in peripheral blood. The fiberoptic bronchoscopic manifestations of PBB were luminal mucosal edema. Eleven patients also had airway malacia. The neutrophil median in BALF was 0.2. The positive rate of bacterial culture of BALF was 36%. The main bacteria were Streptococcus pneumoniae (50%) and Haemophilus influenzae (30%). The main treatment for PBB patients included amoxycillin/clavulanate potassium and second-generation cephalosporins. The average duration of treatment was (17.3 ± 3.2)days, the prognosis was good. CONCLUSION: PBB is common in male infants. Persistent wet cough with wheezing was the main characteristic of PBB. PBB is commonly accompanied by immune dysfunction and airway malacia, and the pathogens were Streptococcus pneumoniae and Haemophilus influenzae.

[Study on dynamic changes of airway hyperresponsiveness in children with cough variant asthma].

OBJECTIVE: To explore the dynamic changes of airway hyperresponsiveness (AHR) in children with cough variant asthma (CVA). METHODS: A prospective observational study was conducted at the Children's Hospital of Soochow University from April 2012 to March 2013. A total of 36 patients were diagnosed as CVA. According to the integral dose of histamine resulting in a 20% (PD20) fall in forced expiratory volume in 1 s (FEV1), the severity of CVA was graded. Corresponding treatment was administered and the dynamic changes of airway hyperresponsiveness were followed for 0, 1 and 6 months. RESULTS: Among them, 14 patients suffered from CVA only while another 22 cases had CVA plus upper airway cough syndrome (UACS). PD20 of CVA and CVA+UACS groups were (0.46 ± 0.26) and (0.58 ± 0.34) mg respectively. No statistically significance existed between two groups (t = -0.880, P > 0.05). According to the value of PD20, AHR in CVA patients was classified into four degrees of severe, moderate, mild and very mild. Initially there were moderate (n = 8), mild (n = 21) and very mild (n = 5). At 1 month follow-up, moderate (n = 1), mild (n = 28) and borderline (n = 7); At 6 month, moderate (n = 2), mild (n = 20) and very mild (n = 7). And 4 cases turned negative and another 3 cases became lost. Cough symptom score and PD20 showed no significant correlation (r = -0.086, P > 0.05). CONCLUSIONS: AHR in CVA patients is predominantly mild and very mild. And it decreases rapidly mostly during initial treatment phase. The proportion of conversion from CVA into negative and typical bronchial asthma is relatively low.