Analysis of Multimorbidity of Moderate to Severe Allergic Rhinitis in Children: A Real-World Study.

INTRODUCTION: Allergic rhinitis (AR) in children is associated with various comorbidities, posing challenges for treatment and management. There have been few investigations of these multimorbidities in Chinese children with AR. Here, we investigated the prevalence of multimorbidities in children with moderate to severe AR and analyzed the influencing factors using real-world data. METHODS: In total, 600 children who visited the outpatient clinic of our hospital and were diagnosed with moderate-severe AR were prospectively enrolled. All children underwent allergen detection and electronic nasopharyngoscopy. Parents or guardians completed a questionnaire that included age, sex, mode of delivery, feeding pattern, and familial history of allergy. The multimorbidities investigated included atopic dermatitis (AD), asthma, allergic conjunctivitis (AC), chronic rhinosinusitis (CRS), adenoid hypertrophy (AH), tonsil hypertrophy (TH), recurrent epistaxis, and recurrent respiratory tract infections (RRTIs). RESULTS: The AR multimorbidities reported in children were as follows: recurrent epistaxis (46.5%), AC (46.3%), AD (40.7%), asthma (22.5%), RRIs (21.3%), CRS (20.5%), AH (19.7%), and TH (12.5%). In univariate logistic regression analysis, age (<6 years), birth mode, familial history of allergy, and single dust mite allergy were associated with AR multimorbidity (p < 0.05). Multivariate logistic regression revealed that a familial history of allergy was an independent risk factor for AC (odds ratio [OR] = 1.539, 95% confidence interval [CI]: 1.104-2.145) and AH (OR = 1.506, 95% CI: 1.000-2.267) (p < 0.05). Age (<6 years) was independently associated with the risk of AD (OR = 1.405, 95% CI: 1.003-1.969) and RRTIs (OR = 1.869, 95% CI: 1.250-2.793) (p < 0.05), cesarean section with AR and CRS risk (OR = 1.678, 95% CI: 1.100-2.561), and single dust mite allergy with asthma (OR = 1.590, 95% CI: 1.040-2.432) and CRS (OR = 1.600, 95% CI: 1.018-2.515) risk (p < 0.05). Further, non-dust mite allergy was independently associated with AR and CRS (OR = 2.056, 95% CI: 1.084-3.899). CONCLUSION: AR was found to be accompanied by different comorbidities, including both allergic and non-allergic comorbidities, complicating disease treatment. These findings demonstrated that age (<6 years), familial history of allergy, types of allergens, and cesarean section were risk factors for different multimorbidities associated with AR.

Age-specific spectrum of etiological pathogens for viral diarrhea among children in twelve consecutive winter-spring seasons (2009-2021) in China.

Viral diarrhea is one of the leading causes of morbidity and mortality in children. This study was conducted to disclose the etiological cause and epidemiological features of viral diarrhea among children in China. From 2009 to 2021, active surveillance was performed on pediatric patients with acute diarrhea and tested for five enteric viruses. Positive detection was determined in 65.56% (3325/5072) patients and an age-specific infection pattern was observed. A significantly higher positive rate was observed in 12-23-month-old children for rotavirus (47.46%) and adenovirus (7.06%), while a significantly higher positive rate was observed for norovirus (37.62%) in 6-11-month-old patients, and for astrovirus (11.60%) and sapovirus (10.79%) in 24-47-month-old patients. A higher positive rate of rotavirus in girls and norovirus in boys was observed only among 6-11 months of patients. We also observed more norovirus among patients from rural areas in the 0-5- and 36-47-month groups and more rotavirus among those from rural areas in the 12-23-month group. Diarrhea severity was greater for rotavirus in the 6-23-month group and norovirus in the 6-11-month group. Coinfections were observed in 29.26% (973/3325) of positive patients, and were most frequently observed between rotavirus and others (89.31%). Our findings could help the prediction, prevention, and potential therapeutic approaches to viral diarrhea in children.

Vasoactive intestinal peptide: a potential target for antiviral therapy.

Viral infection is clinically common and some viral diseases, such as the ongoing global outbreak of coronavirus disease 2019 (COVID-19), caused by severe acute respiratory syndrome coronavirus-2 (SARS-CoV-2), have high morbidity and mortality. However, most viral infections are currently lacking in specific therapeutic agents and effective prophylactic vaccines, due to inadequate response, increased rate of drug resistance and severe adverse side effects. Therefore, it is urgent to find new specific therapeutic targets for antiviral defense among which "peptide-based therapeutics" is an emerging field. Peptides may be promising antiviral drugs because of their high efficacy and low toxic side effects. Vasoactive intestinal peptide (VIP) is a prospective antiviral peptide. Since its successful isolation in 1970, VIP has been reported to be involved in infections of SARS-CoV-2, human immune deficiency virus (HIV), vesicular stomatitis virus (VSV), respiratory syncytial virus (RSV), Zika virus (ZIKV) and cytomegalovirus (CMV). Additionally, given that viral attacks sometimes cause severe complications due to overaction of inflammatory and immune responses, the potent anti-inflammatory and immunoregulator properties of VIP facilitate it to be a powerful and promising candidate. This review summarizes the role and mechanisms of VIP in all reported viral infections and suggests its clinical potential as an antiviral therapeutic target.

[Neuro-immune interactions in respiratory diseases].

The nervous system and the immune system are relatively independent but interactional, and neuro-immune regulation is very important for the respiratory system to resist external harmful stimuli and to maintain homeostasis. Neuro-immune interaction is involved in the occurrence and development of respiratory diseases, and is essential for monitoring and modulating inflammation and tissue repair. This article summaries the neuro-immune regulation of respiratory system and discusses its role in respiratory diseases, aiming to provide a theoretical basis for further understanding the crosstalk between the nervous and immune systems, to explore the underlying mechanism in respiratory diseases, and to provide new thoughts for the prevention and treatment of respiratory diseases.

Publishing clinical prActice GuidelinEs (PAGE): Recommendations from editors and reviewers.

Transparency Ecosystem for Research and Journals in Medicine (TERM) working group summarized the essential recommendations that should be considered to review and publish a high-quality guideline. These recommendations from editors and reviewers included 10 components of essential requirements: systematic review of existing relevant guidelines, guideline registration, guideline protocol, stakeholders, conflicts of interest, clinical questions, systematic reviews, recommendation consensus, guideline reporting and external review. TERM working group abbreviates them as PAGE (essential requirements for Publishing clinical prActice GuidelinEs), and recommends guideline authors, editors, and peer reviewers to use them for high-quality guidelines.

The Impact of Weather and Air Pollution on Viral Infection and Disease Outcome Among Pediatric Pneumonia Patients in Chongqing, China, from 2009 to 2018: A Prospective Observational Study.

BACKGROUND: For pediatric pneumonia, the meteorological and air pollution indicators have been frequently investigated for their association with viral circulation but not for their impact on disease severity. METHODS: We performed a 10-year prospective, observational study in 1 hospital in Chongqing, China, to recruit children with pneumonia. Eight commonly seen respiratory viruses were tested. Autoregressive distributed lag (ADL) and random forest (RF) models were used to fit monthly detection rates of each virus at the population level and to predict the possibility of severe pneumonia at the individual level, respectively. RESULTS: Between 2009 and 2018, 6611 pediatric pneumonia patients were included, and 4846 (73.3%) tested positive for at least 1 respiratory virus. The patient median age was 9 months (interquartile range, 4‒20). ADL models demonstrated a decent fitting of detection rates of R2 > 0.7 for respiratory syncytial virus, human rhinovirus, parainfluenza virus, and human metapneumovirus. Based on the RF models, the area under the curve for host-related factors alone was 0.88 (95% confidence interval [CI], .87‒.89) and 0.86 (95% CI, .85‒.88) for meteorological and air pollution indicators alone and 0.62 (95% CI, .60‒.63) for viral infections alone. The final model indicated that 9 weather and air pollution indicators were important determinants of severe pneumonia, with a relative contribution of 62.53%, which is significantly higher than respiratory viral infections (7.36%). CONCLUSIONS: Meteorological and air pollution predictors contributed more to severe pneumonia in children than did respiratory viruses. These meteorological data could help predict times when children would be at increased risk for severe pneumonia and when interventions, such as reducing outdoor activities, may be warranted.

[Clinical effect of azithromycin adjuvant therapy in children with bronchiolitis: a systematic review and Meta analysis].

OBJECTIVE: To systematically evaluate the clinical effect of azithromycin (AZM) adjuvant therapy in children with bronchiolitis. METHODS: Related databases were searched for randomized controlled trials (RCTs) on AZM adjuvant therapy in children with bronchiolitis published up to February 17, 2019. RevMan 5.3 was used to perform the Meta analysis. RESULTS: A total of 14 RCTs were included, with 667 children in the intervention group and 651 in the control group. The pooled effect size showed that in the children with bronchiolitis, AZM adjuvant therapy did not shorten the length of hospital stay (MD=-0.29, 95%CI: -0.62 to 0.04, P=0.08) or oxygen supply time (MD=-0.33, 95%CI: -0.73 to 0.07, P=0.10), while it significantly shortened the time to the relief of wheezing (MD=-1.00, 95%CI: -1.72 to -0.28, P=0.007) and cough (MD=-0.48, 95%CI: -0.67 to -0.29, P<0.00001). The analysis of bacterial colonization revealed that AZM therapy significantly reduced the detection rates of Streptococcus pneumoniae (OR=0.24, 95%CI: 0.11-0.54, P=0.0006), Haemophilus (OR=0.28, 95%CI: 0.14-0.55, P=0.0002), and Moraxella catarrhalis (OR=0.21, 95%CI: 0.11-0.40, P<0.00001) in the nasopharyngeal region. CONCLUSIONS: AZM adjuvant therapy can reduce the time to the relief of wheezing and cough in children with bronchiolitis, but it has no marked effect on the length of hospital stay and oxygen supply time.

Epidemiological analysis and follow-up of human rhinovirus infection in children with asthma exacerbation.

To determine the prevalence of human rhinovirus (HRV) infection in children with acute asthma exacerbations, investigation of HRV viral load and severity of asthma exacerbations is also required. Nasopharyngeal aspirates and swabs were collected and assessed for respiratory viruses. HRV-positive samples were sequenced to identify types and determine viral load. Outpatients with asthma exacerbations underwent follow-up evaluations, their swabs were collected and clinical outcomes were recorded at their next clinic visit 4 weeks later. One hundred forty-three inpatients and 131 outpatients, including 88 patients with asthma exacerbations and 43 controls with stable asthma were recruited. HRV-A was mainly detected in September and February (45.5% and 33.3%, respectively), while HRV-C was mainly detected in November and April (70.0% and 55.6%, respectively). HRV-C was the primary type and was primarily found in inpatients with severe asthma exacerbations. HRV-A viral load in the group of inpatients with severe exacerbations was higher than in the mild and moderate groups (P < 0.001 and P = 0.022). The HRV-A viral load of both inpatients and outpatients was higher than that of HRV-C (P < 0.001 and P = 0.036). The main genotypes were HRV-C53 and HRV-A20 among inpatients, and this genotype caused more severe clinical manifestations. HRV persisted for no more than 4 weeks, and their symptoms or signs of disease were well-controlled well. HRV-C was most frequently detected in asthma exacerbations. HRV-A with high viral load led to severe asthma exacerbations.

Pediatric allergy and immunology in China.

Over the past 30 years, China has enjoyed rapid economic development along with urbanization at a massive scale that the world has not experienced before. Such development has also been associated with a rapid rise in the prevalence of allergic disorders. Because of the large childhood population in the country, the burden of childhood allergic disorders has become one of the major challenges in the healthcare system. Among the Chinese centers participating in the International Study of Asthma and Allergies in Childhood, the data clearly showed a continuing rise in the prevalence of asthma, allergic rhinitis, and atopic eczema. However, the discipline of pediatric allergy in mainland China is still in its infancy due to the lack of formal training program and subspecialty certification. Clinicians and researchers are increasingly interested in providing better care for patients with allergies by establishing pediatric allergy centers in different regions of the country. Many of them have also participated in national or international collaborative projects hoping to answer the various research questions related to the discipline of pediatric allergy and immunology. It is our hope that the research findings from China will not only improve the quality of care of affected children within this country but also the millions of patients with allergies worldwide.

Establishing a Role for Interleukin-17 in Atopic Dermatitis-Related Skin Inflammation.

BACKGROUND: Although CD4+ T cells are known to contribute to the pathology of atopic dermatitis (AD), the role of T helper 17 cells and interleukin (IL)-17 in skin inflammation remains poorly understood. The aim of this study was to characterize the role of IL-17 in AD-related inflammation and immunopathology. METHODS: Blood samples were collected from 87 children with AD and 60 healthy control subjects. In addition, 10 skin biopsies from each group were collected. Skin and serum expression levels of IL-17 were analyzed by immunohistochemistry and enzyme-linked immunosorbent assay, respectively. 2,4-Dinitrochlorobenzene (DNCB)-sensitized IL-17 knockout and wild-type mice were used as an animal model of skin AD. The messenger ribonucleic acid expression levels of T helper types 1 and 2 cytokines isolated from mouse skin biopsies were determined by quantitative polymerase chain reaction. Cytokine expression profiles of concanavalin A-stimulated splenocytes and IL-17-treated HaCaT keratinocytes were determined. RESULTS: IL-17 expression levels were significantly elevated in the skin, but not in the serum, of patients with AD compared with healthy control subjects. Compared with control subjects, skin lesions from AD animal models exhibited significantly reduced epidermal and dermal thicknesses, as well as reduced messenger ribonucleic acid expression levels of T helper type 2 cytokines IL-4 and IL-13. Concanavalin A-stimulated splenocytes isolated from DNCB-treated IL-17 knockout mice showed significantly less production of IL-4 and IL-5 compared with wild-type controls. IL-6 and IL-8 production by IL-17-stimulated HaCaT cells was blocked by inhibitors of p38 kinase and extracellular signal-regulated kinase. CONCLUSIONS: IL-17 may mediate AD-related immune dysregulation by amplifying the inflammatory response.

[Levels of surfactant proteins A and D in bronchoalveolar lavage fluid of children with pneumonia and their relationships with clinical characteristics].

OBJECTIVE: To observe the levels of pulmonary surfactant proteins A and D (SP-A, SP-D) in bronchoalveolar lavage fluid (BALF) of children with pneumonia, and to explore their relationships with clinical characteristics. METHODS: Thirty-five children with pneumonia were enrolled in this study. Differential cell counts were obtained by Countstar counting board. The levels of SP-A and SP-D in BALF were detected using ELISA. RESULTS: In children with pneumonia, SP-D levels were significantly higher than SP-A levels (P<0.001). SP-D levels were negatively correlated with the neutrophil percentage in BALF (r(s)=-0.5255, P<0.01). SP-D levels in BALF in children with increased blood C-reactive protein levels (>8 mg/L) were significantly lower than in those with a normal level of C-reactive protein (P<0.05). Compared with those in children without wheezing, SP-D levels in children with wheezing were significantly lower (P<0.01). There was no correlation between SP-A levels and clinical characteristics. CONCLUSIONS: SP-D levels in BALF are significantly higher than SP-A levels, and have a certain correlation with clinical characteristics in children with pneumonia. As a protective factor, SP-D plays a more important role than SP-A in regulating the immune and inflammatory responses.

[Airway inflammation induced by Poly(I:C) stimulation in the late stage of respiratory syncytial virus infection in mice and its mechanism].

OBJECTIVE: To investigate the pathogenic mechanisms of airway inflammation and recurrent wheezing induced by recurrent respiratory virus infection after respiratory syncytial virus (RSV) infection. METHODS: Sixty-four female BALB/c mice (aged 6-8 weeks) were randomly divided into four groups: control, RSV, Poly(I:C), and RSV+Poly(I:C) (n=16 each). The bronchoalveolar lavage fluid (BALF) was collected on the 3rd day after Poly(I:C) administration, and the total cell number and differential counts in BALF were determined. Hematoxylin-eosin staining was used to observe pulmonary pathological changes. The airway responsiveness was detected. ELISA was used to measure the levels of interferon-γ (IFN-γ), interleukin-4 (IL-4), interleukin-13 (IL-13), matrix metallopeptidase-9 (MMP-9), and tissue inhibitor of metalloproteinase-1 (TIMP-1) in BALF. RESULTS: Compared with the other three groups, the RSV+Poly(I:C) group had significant increases in the total number of inflammatory infiltrating cells in the airway, airway responsiveness, and MMP-9 level in BALF (P<0.05). The RSV+Poly(I:C) group showed more severe pulmonary tissue injuries compared with the control and RSV groups (P<0.01). Compared with the RSV group, the RSV+Poly(I:C) group showed significant reductions in the levels of IL-4 and TIMP-1 in BALF (P<0.01). CONCLUSIONS: Viral re-infection in the late stage of RSV infection may cause an imbalance of MMP-9/TIMP-1 expression and thus contribute to aggravated airway inflammation.

Association of Pneumococcal Carriage and Expression of Foxp3+ Regulatory T Cells and Th17 Cells in the Adenoids of Children.

BACKGROUND: Pneumococcal carriage in the nasopharynx is a primary means of transmission and a necessary prerequisite for pneumococcal disease. OBJECTIVES: We analyzed the relationship between expressions of Foxp3+ regulatory T (Treg) cells and Th17 cells, and pneumococcal carriage in the adenoids of children who were either positive or negative for pneumococci. METHODS: We collected adenoidal tissue and nasopharyngeal swab samples from children undergoing an adenoidectomy. Adenoidal mononuclear cells were isolated, cultured and then stimulated with culture concentrated supernatant (CCS) obtained from a D39 bacterial strain. RESULTS: Foxp3+ Treg cells were upregulated and Th17 cells were downregulated in populations of adenoidal mononuclear cells obtained from the pneumococcus-positive group. Following CCS stimulation, the increment in Foxp3+ Treg cells in the pneumococcus-positive group was significantly greater than that in the pneumococcus-negative group, while the increment in Th17 cells was less as compared to that in the pneumococcus-negative group. These results were consistent with variations in levels of Foxp3 mRNA and retinoic acid receptor-related orphan receptor-γt mRNA in adenoidal mononuclear cells. Levels of IL-17A and IL-6 in adenoid tissue were higher in the pneumococcus-negative group, and the levels of TGF-ß in adenoid tissue were lower in the pneumococcus-negative group compared to the pneumococcus-positive group. Pneumococcal carriage in children was closely associated with the expressions of Foxp3+ Treg and Th17 cells in the adenoid. CONCLUSION: Upregulation of Foxp3+ Treg cells might downregulate the production of Th17 cells in the adenoid, resulting in decreased scavenging of Streptococcus pneumoniae and chronic pneumococcal carriage.

Indoor Allergen Levels and Household Distributions in Nine Cities Across China.

OBJECTIVE: Chinese allergic subjects have high levels of sensitization to house dust mite (HDM) and other indoor allergens. This study quantifies common indoor allergen levels in Chinese households. METHODS: Dust samples were collected from nine cities. Major allergens Der p 1 and Der f 1 from Dermatophagoides pteronyssinus and D. farinae, and specific antigens of Blomia tropicalis, Tyrophagus putrescentiae, Acarus siro, and cockroach species Blattella germanica and Periplaneta americana were measured by ELISA. RESULTS: HDM allergens were found in dust samples from bedding in 95% of the Chinese households. The median levels varied from <0.006 to 9.2 µg/g of dust, depending on the city. The percentages of households having HDM allergen levels associated with the risk of developing allergy sensitization and asthma were 65% and 25%, respectively. Specific antigens of the storage mite and cockroach were only found in samples from the southern and tropical regions of China. Levels of mite allergens were generally higher in samples from bedding compared to samples from the living room, even for storage mites, whereas levels of cockroach antigens were higher in the living room samples. CONCLUSION: HDM allergens are present in bedding dust samples from most Chinese households. Cities in southern and central China have relatively high levels of HDM major allergens compared to cities in northern and western China. Antigens of storage mites and cockroaches are not as common as HDM allergens.

Systematic review of montelukast's efficacy for preventing post-bronchiolitis wheezing.

Infants often develop reactive airway diseases subsequent to respiratory syncytial virus (RSV) bronchiolitis. Cysteinyl leukotrienes (cysLTs), a class of lipid mediators that have been implicated in the pathogenesis of allergic rhinitis and asthma, are released during RSV infection, thereby contributing to the pathogenic changes in airway inflammation. Many pediatric patients, especially those of very young age, continue to have recurrent episodes of lower airway obstruction after bronchiolitis treatment. This study was to systematically review and assessed the efficacy of montelukast for preventing wheezing in patients with post-bronchiolitis. The Cochrane library, PubMed, China National Knowledge Infrastructure (CNKI) periodical databases were screened for studies related to use of montelukast for preventing post-bronchiolitis wheezing published up to 31 December 2012. Randomized controlled trials (RCTs) and quasi-RCTs using montelukast alone as an active intervention in infants up to 24 months of age with post-bronchiolitis were selected. Two authors independently extracted data and assessed trial quality using the recommendations published by the Cochrane Collaboration. The meta-analyses were performed using the Cochrane statistical package RevMan5.0.0. Four trials, containing 1430 infants with confirmed diagnosis of acute bronchiolitis, were analyzed. Patients were administered montelukast at post-bronchiolitis. Three trials showed no effects of montelukast on reducing the incidence of recurrent wheezing risk ratios (RR = 0.78, 95% CI: 0.55-1.12, p = 0.17), while two trials found that montelukast did reduce the frequency of recurrent wheezing and another two trials demonstrated no effects of montelukast on symptom-free days. The pooled montelukast treatment group showed no significant effect on reducing the usage of corticosteroids, as compared to the placebo group (RR = 1.11, 95% CI: 0.85-1.44, p = 0.45). Two trials showed that montelukast significantly decreased serum eosinophil-derived neurotoxin levels, as compared to the control group. In general, the side effects of rash, vomiting, and insomnia caused by montelukast occurred in 1.5% of patients analyzed. The recent evidences indicate that montelukast may reduce the frequency of post-bronchiolitic wheezing without causing significant side effects but that it has no effects on decreasing incidences of recurrent wheezing, symptom-free days, or the associated usage of corticosteroid in post-bronchiolitis patients. The small number of enrolled participants and the inability to pool all clinical outcomes precludes us from making solid recommendations.

Detection and complete genome characterization of human enterovirus 118 from children with acute respiratory disease in China.

Enterovirus 118 (EV-118) within species HEV-C was detected in two 5-month-old boys with pneumonia in China. The EV-118 from both cases was genetically closer to ISR10 strain from Israel than to PER161 strain from Peru based on VP1 gene sequences. The complete genome of the detected EV-118 consists of 7,360 nucleotides, excluding the poly (A) tail. The 5'UTR contains 669 nucleotides, and 3'UTR consists of 73 nucleotides. A single open reading frame from base 670 to 7,287 that encodes a 2,206-amino-acid polyprotein was featured. The base composition of the full genome is 27.9 % A, 24.2 % C, 24.4 % G, and 23.6 % U. Phylogenetic analysis of the full genome sequences illustrated EV-118 was genetically closer to EV-109 and EV-105, and the Chinese strain differed from Peru strain. In summary, the presence of EV-118 was confirmed in pediatric pneumonia cases and complete genome sequences were identified for the first time in China.

[Clinical analysis of 28 cases of bronchiolitis obliterans].

OBJECTIVE: To study the clinical features of bronchiolitis obliterans (BO) in children. METHODS: The clinical data of 28 children with BO between July 2007 and April 2012 was retrospectively reviewed. RESULTS: All patients presented with persistent or repeated cough and wheezing. Twenty-three cases were post-infectious bronchiolitis obliterans (PIBO), among whom the etiology were adenovirus (12 cases), measles (2 cases), influenza virus A (2 cases), mycoplasma pneumoniae (1 case), mycoplasma pneumoniae coinfection with adenovirus (1 case), respiratory syncytial virus coinfection with Parainfluenza type 3 virus (1 case) and pulmonary tuberculosis (1 case). The etiology of 3 cases was not associated with infection. The etiology was unknown in 2 cases. Pulmonary HRCT revealed that decreased density in 25 cases, mosaic perfusion in 21 cases, bronchial wall thickening in 15 cases, bronchiectasis in 12 cases and air retention in 6 cases. Lung function test was performed on 21 cases and demonstrated that obstructive ventilation disorder in all 21 cases. Bronchodilation test was performed on 18 cases and 17 cases showed a negative result. All 28 cases received corticosteroid treatment, and 24 cases were orally administered with low doses of azithromycin. One case died during hospitalization. Eighteen cases were followed up for 4 months to 4 years and seven months. Clinical manifestations were improved in 12 cases and one case died. CONCLUSIONS: Low respiratory infection is the most common cause of pediatric BO and adenovirus is a major pathogen. Persistent wheezing and cough were main clinical manifestations. Pulmonary HRCT imaging is important for diagnosis and follow-up of BO. Lung function test can typically show obstructive ventilation disorder. Corticosteroid and methotrexate may be effective for treatment of BO. Prognosis of this disease is unsatisfactory. Early diagnosis and treatment, and avoidance of repeated respiratory tract infection may be helpful to improve the prognosis.

Preterm birth and detection of common respiratory pathogens among pediatric pneumonia.

Pneumonia complicated by preterm birth is related to adverse clinical sequelae from the neonatal period to childhood. Children with pneumonia during 2009-2021 were enrolled at the Children's Hospital of Chongqing Medical University. Altogether 20 respiratory pathogens were detected and compared. Among 8,206 children, 779 were in the preterm group with 246 of early-preterm and 533 of late preterm. The positive rates for all viral pathogens were comparable between the preterm group and the full-term group. For bacterial pathogens, higher positive rates for Escherichia coli and Klebsiella pneumoniae were observed in the preterm group. Severe pneumonia developed in 16.52% of all, which was higher in the preterm group than in the full-term group. A significantly higher rate of severe pneumonia was observed in the early-preterm group compared to the late-preterm group. Preterm birth has an impact on the detection of bacterial pathogens in children and is a risk factor for severe pneumonia.

Detection and genetic diversity of human metapneumovirus in hospitalized children with acute respiratory infections in Southwest China.

Human metapneumovirus (hMPV) is the main pathogen causing respiratory tract infection in susceptible populations, particularly in children and the elderly. Specimens were collected from hospitalized children with acute lower respiratory tract infections (ALRTI), and the hMPV was detected by using real-time reverse transcription-PCR (RT-PCR). The full-length G gene of hMPV was amplified by RT-PCR. A total of 1,410 nasopharyngeal aspirates (NPAs) were collected from April 2008 to March 2011, and 114 (10.2%) were positive for hMPV. Most hMPV-positive children were <5 years of age. The hMPV infection rate peaked in the spring-summer season of 2008 to 2009 and 2009 to 2010, while hMPV circulated predominantly during the winter-spring season of 2010 to 2011. The full-length G gene of 23 hMPV strains was amplified, and group A and B viruses accounted for 95.7% (22/23) and 4.3% (1/23), respectively. Genotype A2b of hMPV appeared to be predominant during the study period. Three genotypes (A2b, A1, and B1) were prevalent in the epidemic season of 2008 to 2009, and only genotype A2b was identified in the other two seasons (2009 to 2010 and 2010 to 2011). The G gene of hMPV was predicted to encode proteins with four different lengths, in which one with 210 amino acids was first identified in China. These findings suggest that hMPV was an important pathogen of ALRTI in pediatric patients, especially those <5 years of age. Genotype A2b of hMPV likely predominates in Southwest China, where other genotypes also circulate.

[Etiology of nonspecific chronic cough in children and relationship between TRPV1 gene polymorphisms and nonspecific chronic cough].

OBJECTIVE: To explore the causes of nonspecific chronic cough in children and relationship between transient receptor potential vanilloid 1 (TRPV1) gene polymorphisms and nonspecific chronic cough. METHODS: A total of 195 children with chronic cough were followed up half a month, one month and three months after their first visit to hospital. Polymerase chain reaction-restriction fragment length polymorphism (PCR-RFLP) was used to examine polymorphisms of the TRPV1 gene in the children. A total of 205 healthy or surgical children without chronic cough served as the control group. RESULTS: The etiologic distribution of the 195 children with chronic cough was as follows: 96 (49.2%) cases of cough variant asthma (CVA), 48 (24.6%) cases of CVA complicated by upper airway cough syndrome (UACS), 34 (17.4%) cases of post-infectious cough, and 17 (8.7%) cases of UACS. Three genotypes were identified in both groups at positions rs222747 (CC, GC and GG), rs222748 (CC, TC and TT) and rs8065080 (CC, TC and TT). The frequencies of genotype and allele at position rs222747 did not accord with the law of Hardy-Weinberg. There was no significant difference in frequencies of genotype and allele at positions rs222748 and rs8065080 between the two groups. CONCLUSIONS: CVA, UACS and post-infectious cough are common causes of nonspecific chronic cough in children. TRPV1 gene polymorphisms at positions rs222748 and rs8065080 may be unrelated to nonspecific chronic cough in children.