Study of association of respiratory viruses in the etiology of acute lower respiratory tract infections in children and correlation with clinical and laboratory features: role of emerging new viruses

Background: Viruses are one of the major causes of childhood pneumonia with the respiratory syncytial virus getting great attention as an important organism for pneumonia. Methods: This cross-sectional study was conducted in the Department of Paediatrics, Sree Gokulam Medical College and Research Foundation, Thiruvananthapuram, Kerala from May 2022 TO November 2022. 119 children admitted with lower respiratory tract infections were included in this study. Symptoms, signs, and investigation reports including PCR and clinical course in the hospital were recorded. Results: 25% of children were in the age group less than 1 year, 52% were between 1-5 years and 23% were above 5 years. Viruses were isolated in 82 patients (68.9%). The main viruses were respiratory syncytial virus (23.5%), boca virus (16.14%), influenza A (7.5%), influenza B (4.2%), meta pneumonia virus (3.3%), and para influenza virus (2.5%). Patients with boca virus infections had a more severe clinical course. Conclusions: Molecular testing with PCR along with clinical and lab parameters will help us to have more insights into the etiology and clinical presentation of respiratory infections in children and help us to do optimum management avoiding unnecessary antibiotic usage.

Clinical application of LAMP in rapid detection of pathogens in lower respiratory tract infections / 中国现代医生

@#Objective Loop mediated isothermal amplification(LAMP)was used to detect the distribution of pathogens in sputum samples,namely combined nucleic acid detection of respiratory pathogens(13 pairs),so as to provide provide reference for clinical accurate diagnosis and treatment.Methods A total of 1642 patients with lower respiratory tract infection admitted to Tongren City People's Hospital from January to December in 2022 were selected.Each patient collected sputum specimens/bronchoalveolar for detection by using LAMP(13 pairs).The detection of pathogenic bacteria in respiratory tract and the relationship with sex,age and season were analyzed.Results The overall detection rate of 13 respiratory pathogens was significantly higher in males than in females(P<0.01);In different age groups,the detection rates of Haemophilus influenzae and Streptococcus pneumoniae in patients aged 3-6,Mycoplasma pneumoniae in patients aged 6-18,and methicillin-resistant Staphylococcus aureus,Streptococcus maltophilus,and Klebsiella pneumoniae in patients aged over 60 were significantly higher than those in other groups(P<0.05);In different seasonal groups,Streptococcus pneumoniae and Chlamydia pneumoniae were more prevalent in spring,while Mycoplasma pneumoniae had the highest infection rate in autumn,and the differences were statistically significant(P<0.05).Conclusion LAMP can be used to detect the pathogen rapidly and provide the basis for clinical diagnosis and treatment.

The association of fibrinogen-albumin ratio and neutrophil-lymphocyte ratio with the severity of respiratory syncytial virus infection in children

ABSTRACT Respiratory syncytial virus (RSV) is a common cause of respiratory infections. It is responsible for more than half of lower respiratory tract infections in infants requiring hospitalization. This study aimed to investigate the correlation between the fibrinogen-albumin ratio (FAR) and the severity of RSV infection and to compare its effectiveness with the neutrophil-lymphocyte ratio (NLR). This was a retrospective cohort study with patients aged from 29 days to two years who had been admitted to the pediatric clinic of our hospital. Patients were divided into four groups: group 1 (mild disease), group 2 (moderate disease), group 3 (severe disease), and group 4 (control). FAR and NLR were measured in all groups. FAR was significantly higher in group 3 than in the other groups, in group 2 than in groups 1 and 4, and in group 1 than in group 4 (p<0.001 for all). NLR was significantly higher in group 4 than in the other groups and in group 3 than in groups 1 and 2 (p<0.001 for all). FAR totaled 0.078 ± 0.013 in patients with bronchiolitis; 0.099 ± 0.028, in patients with bronchopneumonia; and 0.126 ± 0.036, in patients with lobar pneumonia, all with statistically significant differences (p<0.001). NLR showed no significant statistical differences. This study found a statistically significant increase in FAR in the group receiving invasive support when compared to that receiving non-invasive support (0.189 ± 0.046 vs. 0.112 ± 0.030; p=0.003). Mechanical ventilation groups showed no differences for NLR. FAR was used to identify severe RSV-positive patients, with a sensitivity of 84.4%, a specificity of 82.2%, and a cutoff value of >0.068. This study determined a cutoff value of ≤1.49 for NLR, with a sensitivity of 62.2% and a specificity of 62.2% to find severe RSV-positive patients. Also, statistically significant associations were found between FAR and hospitalization and treatment length and time up to clinical improvement (p<0.001 for all). NLR and hospitalization and treatment length showed a weak association (p<0.001). In children with RSV infection, FAR could serve to determine disease severity and prognosis and average lengths of hospitalization, treatment, and clinical improvement. Additionally, FAR predicted disease severity more efficiently than NLR.

Evaluation of prescription pattern of antimicrobials in the treatment of respiratory tract infections in pediatric patients attending a tertiary care hospital

Background: Irrational use of antimicrobials is a complex and multifactorial problem in developing countries. Prescriptions not adhering to the treatment guidelines, self-medication, inappropriate use of drugs by patients can inadvertently lead to development of antimicrobial resistance. An observational study was designed to evaluate antimicrobial use in pediatric population with respiratory tract infections and its adherence to national treatment guidelines. Methods: This was a cross sectional observational study initiated after taking institutional ethics committee permission. The prescriptions of children diagnosed with upper respiratory tract infections and lower respiratory tract infections (LRTI) were screened. Their demographic profile and details of drugs prescribed were recorded. Results: Out of 230 pediatric prescriptions,155 (67%) were from outpatient department and 75 (33%) from those admitted in ward. Total 145 children were diagnosed with URTI whereas 85 had LRTI. In this study, 60 children with URTI received combination of amoxicillin and clavulanic acid (Co-amoxiclav) whereas 66 children with LRTI received Co-amoxiclav,18 ceftriaxone (N=18), 6 vancomycin (N=6) and 18 were prescribed oseltamivir (N=18), either alone or in combination. Other drugs prescribed included, paracetamol for fever and cough syrups. Out of 195 drugs prescribed by brand names, 138 (70.8%) were antimicrobials. Fixed dose combination amoxicillin and clavulanic acid, paracetamol and cough syrups were available from hospital pharmacy. None of the prescriptions had polypharmacy. Conclusions: URTI was treated using single antimicrobial whereas LRTI was treated with more than one antimicrobials or combination of antimicrobial and antiviral agent. The prescriptions were in accordance with the national treatment guidelines.

Epidemiological characteristics and risk factors of rotavirus lower respiratory tract infection in preschool children / 公共卫生与预防医学

Objective To investigate and study epidemiological characteristics and risk factors of rotavirus lower respiratory tract infection in preschool children. Methods The preschool children with rotavirus enteritis and lower respiratory tract infection admitted to the hospital were retrospectively analyzed January 2021 and June 2022. The situations and risk factors of lower respiratory tract infection were evaluated by chest X-ray, serological examination and throat swab culture. Results In the 155 preschool children with rotavirus enteritis, there were 59 (38.06%) cases with lower respiratory tract infection. The results of pathogens culture showed that proportion of Haemophilus influenzae was the highest (28.81%), followed by Streptococcus pneumoniae and Klebsiella pneumoniae (18.64%, 15.25%). There were significant differences between infection group and non-infection group in age, histories of family members smoking, children's aggregated activities and family members' respiratory diseases, family members' and children' attention to hand hygiene, pregnancy outcomes, age at the first usage of antibiotics and onset seasons (P0.05). Logistic regression analysis showed that age <3 years (OR=2.962, P=0.031), history of family members' smoking (OR=2.869, P=0.035), history of family members' respiratory diseases (OR=2.354, P=0.039) and the age at the first usage of antibiotics <1 year (OR=2.622, P=0.033) were all independent risk factors of rotavirus lower respiratory tract infection in preschool children. Conclusion The preschool children with rotavirus are prone to lower respiratory tract infection. Clinically, more attentions should be payed to children with age <3 years, history of family members' smoking, history of family members' respiratory diseases and the age at the first usage of antibiotics <1 year. The targeted measures should be actively taken to prevent the risk of lower respiratory tract infection.

Distribution and drug resistance of pathogenic bacteria in lower respiratory tract of 276 hospitalized children / 公共卫生与预防医学

Objective To analyze the epidemiological characteristics and drug resistance of pathogenic bacteria in 276 hospitalized children with lower respiratory tract infection to facilitate prevention and treatment. Methods Among of 276 hospitalized children with lower respiratory tract infection from January 2019 to December 2021 were analyzed. Data on the distribution of pathogenic bacteria were collected and analyzed. At the same time, the information on drug resistance was collected, and the potential relationship between pathogen distribution and drug resistance was briefly analyzed and discussed. Results A total of 532 strains of pathogenic bacteria were detected in the blood samples from 276 patients in this study. There were 207 strains of Gram-positive bacteria, including 104 strains of Staphylococcus aureus, 96 strains of Staphylococcus epidermidis and 7 strains of others. Gram negative bacteria (325 strains) were 172 strains of Klebsiella and 153 strains of Escherichia coli. The distribution of pathogenic bacteria in different gender and age groups (under 5 years old, 5-10 years old, and over 10 -14 years old) was calculated separately. The results showed that the distribution of pathogenic bacteria in female children under 5 years old (n=49 cases) was different from the total population: the infection of Gram-positive bacteria was higher than that of Gram-negative bacteria, and the proportion of Staphylococcus epidermidis was the highest (P<0.05). The distribution characteristics of children of other ages and sexes were consistent with the total distribution characteristics. The resistance rate of Gram-positive bacteria to penicillin, erythromycin and clarithromycin was high, while the resistance rate of Gram-negative bacteria to ampicillin, cefazolin and cefuroxime was high. The distribution characteristics were the same in children of different sex and age. Conclusion The pathogenic bacteria in children with lower respiratory tract infection in pediatric ward are mainly Gram-negative bacteria, and the main pathogenic bacteria have a high resistance rate to common drugs. The distribution of pathogenic bacteria in female children under 5 years old is unique: the infection of Gram-positive bacteria is higher than that of Gram-negative bacteria, and the proportion of Staphylococcus epidermidis is the highest, which deserves attention. The clinical drug sensitivity test can be used as an important reference for the treatment of drugs to guide the rational selection of antibiotics.

A Study to Assess the Effectiveness of Balloon Therapy on Lung Capacity of Patients with Lower Respiratory Tract Infections in Selected Hospital of Chitrakoot U.P.

As per 2019 report of the National Health Portal of India, 41,996,260 cases and 3,740 deaths from respiratory infections were recorded across India in 2018. The main aim of the study was to assess the effectiveness of balloon therapy on increased level of oxygenation of patients with lower respiratory tract disorders. Quasi experimental design was used for this study. Balloon therapy improves pulmonary functions. Daily practice of blowing up balloon, once a day, 10 times per day for 10 days will steadily increase lung capacity. The data pertaining to lung capacity was collected using self-administered questionnaire. Respiratory assessment viz Vital, Tidal and Lung capacity were measured using balloon therapy. The pre-test mean and SD were 6.83 & 1.30 respectively where as posttest mean & SD were 7.16 & 1.26, with t-test value of 6.12. These reading indicate the effectiveness of Balloon therapy on lung capacity in patients with lower respiratory tract infections. The result of this study guides that regular practice of balloon therapy can improve the lung capacity to a greater extent among patients with lower respiratory tract infection. Off course, large sample size is recommended for generalization.

Distribution and antimicrobial resistance pattern of bacteria isolated from alveolar lavage fluid in pediatric patients with lower respiratory tract infection / 中华传染病杂志

Objective:To analyze the distribution and antimicrobial resistance pattern of bacteria isolated from alveolar lavage fluid in pediatric patients with lower respiratory tract infection from 2016 to 2018.Methods:The alveolar lavage fluid of pediatric patients aged <18 years old with lower respiratory tract infection in ten hospitals from January 2016 to December 2018 were collected, and the pathogenic bacteria were cultured and isolated. The paper diffusion method or minimum inhibitory concentration method was used to conduct drug susceptibility tests for the isolated strains.The distribution of pathogenic bacteria and the source department of the strains were analyzed.Chi-sqare test was used for statistical analysis.Results:Of 1 271 isolates, 606 strains (47.7%) were gram-negative bacteria, 628 strains (49.4%) were gram-positive bacteria, and 37 strains (2.9%) were fungi. The common pathogens were Streptococcus pneumoniae (36.7%, 466/1 271), Acinetobacter baumannii (16.8%, 214/1 271), Staphylococcus aureus (12.7%, 162/1 271), Klebsiella pneumoniae (8.3%, 105/1 271), Haemophilus influenzae (7.4%, 94/1 271), Pseudomonas aeruginosa (6.2%, 79/1 271), Burkholderia cepacia (5.3%, 67/1 271) and Escherichia coli (3.7%, 47/1 271). The main pathogens in the intensive care unit (ICU) were gram-negative bacteria (80.1%, 428/534), among which Acinetobacter baumannii was the most common (3.7%, 199/534). The main pathogens in the non-ICU were gram-positive bacteria (70.8%, 522/737). The detection rates of methicillin-resistant Staphylococcus aureus (MRSA) were 45.1%(23/51) in the ICU and 43.2% (48/111) in the non-ICU, respectively. The detection rates of penicillin-resistant Streptococcus pneumoniae (PRSP) were 10.9%(6/55) in the ICU and 18.5% (76/411) in the non-ICU, respectively. The detection rates of carbapenem-resistant Klebsiella pneumoniae (CRKP) were 57.3%(43/75) in the ICU and 33.3%(10/30) in the non-ICU, respectively. The detection rate of carbapenem-resistant Pseudomonas aeruginosa (CRPA) in the ICU was higher than that in the non-ICU (49.1%(27/55) vs 25.0%(6/24)), and the difference was statistically significant ( χ2=3.98, P=0.046). Eight strains (17.0%) of carbapenem-resistant Escherichia coli were detected, and 164 strains(76.6%) of carbapenem-resistant Acinetobacter baumannii were detected. Seventy-eight Haemophilus influenzae isolates were isolated from non-ICU, and the resistance rate to ampicillin was 57.4%(54/94). Burkholderia cepacia isolates were all isolated from ICU, and the resistance rates to piperacillin-tazobactam, levofloxacin, ciprofloxacin and compound sulfamethoxazole were 13.4%(9/67), 3.0%(2/67), 0(0/67) and 9.0%(6/67), respectively. Conclusions:Streptococcus pneumoniae is still the most common pathogen in pediatric patients with lower respiratory tract infection. Gram-negative bacilli are the main pathogens in pediatric patients with lower respiratory tract infection in the ICU. The dection rates of MRSA, PRSP and carbopenem-resistant gram-negative bacilli are high. And the resistance rate of Haemophilus influenzae to ampicillin is also high. The clinical empirical treatment should be determined according to different clinical background.

Epidemiological study of pathogens in hospitalized children with lower respiratory tract infection in a single center of Shanghai from 2015 to 2019 / 中华传染病杂志

Objective:To analyze common respiratory pathogens epidemiology in hospitalized children with lower respiratory tract infection (LRTI) in a single center in Shanghai, and to provide the basic data support for clinical diagnosis and treatment of children with LRTI in Shanghai.Methods:Children with LRTI in Children′s Hospital of Fudan University were enrolled from January 1, 2015 to December 31, 2019, and respiratory samples were collected and tested by direct immunofluorescence assay and real time polymerase chain reaction. The epidemiological characteristics of different respiratory pathogens were analyzed. Chi-square test was used for statistical analysis.Results:A total of 18 716 children were included, the total detection rate of respiratory pathogens was 36.96% (6 918/18 716), and the most frequent detected pathogen was Mycoplasma pneumoniae (MP) (15.31%(2 866/18 716)), followed by respiratory syncytial virus (RSV) (10.40%(1 946/18 716)) and parainfluenza virus Ⅲ (PIV-Ⅲ) (4.65%(871/18 716)). The detection rate of pathogens in female was significantly higher than that in male (38.48%(2 936/7 630) vs 35.92%(3 982/11 086), χ2=12.72, P<0.001). RSV and influenza virus A (Flu-A) infections peaked in winter. The detection rates of influenza virus B (Flu-B) and human metapneumovirus (MPV) were higher in winter and spring. PIV-Ⅲ infection peaked in spring and summer. The peak of PIV-Ⅱ infection occurred in summer and autumn. The infections of adenovirus (ADV), MP, Chlamydia trachomatis (CT) and PIV-Ⅰ were prevalent throughout the year without significant seasonality. The detection rate of RSV declined with age, while the detection rate of MP increased with age. The co-infection rate was 1.65%(309/18 716), and the predominant co-infection type was MP and RSV (0.37%(70/18 716)). Conclusions:A variety of pathogens lead to children′s LRTI in Shanghai from 2015 to 2019, with the common infection of MP, RSV and PIV-Ⅲ. Different pathogens showed different epidemiological characteristics in age and season distributions.

Human bocavirus infection in children hospitalized with lower respiratory tract infections: Does viral load affect disease course?

Objective: To examine the effects of human bocavirus type 1 (HBoV1) on the course of lower respiratory tract infections in cases of monoinfection and coinfection, and the effects of HBoV1 viral load on the disease in children under six years old hospitalized with a diagnosis of HBoV1-associated lower respiratory tract infections. Methods: Children under six years of age, who were hospitalized with the diagnosis of lower respiratory tract infection due to HBoV1 between 1 January 2021 and 1 January 2022 were included in the study. Laboratory confirmation of the respiratory pathogens was performed using polymerase chain reaction (PCR). Results: Fifty-four (16.4%) children with HBoV1 among 329 children whose PCR was positive with bacterial/viral agent in nasopharyngeal swab samples were included in the study. There were 28 (51.9%) males and 26 (48.1%) females with a median age 23.4 months [interquartile range (IQR): 13.2, 30.0 months] (min-max:1 month-68 months). HBoV1 was detected as a monoinfecton in 26 (48.1%) children, and as a coinfection with other respiratory agents in 28 children (51.9%). In multiple regression analysis, coinfection (P=0.032) was associated with the length of hospitalization (P<0.001; R 2 =0.166). There was a negative correlation (r= 0.281, P=0.040) between cough and cycle threshold. Fever was found to be positively correlated with C-reactive protein (r=0.568, P<0.001) and procalcitonin (r=0.472; P=0.001). Conclusions: Although we found a higher HBoV1 viral load in children with more cough symptoms in our study, it had no effect on the severity of the disease, such as length of hospital stay and need for intensive care. Coinfection was found to affect the length of hospitalization.

Safety, tolerability and efficacy of LEGA-Kid® mechanical percussion device versus conventional chest physiotherapy in children: a randomised, single-blind controlled study

INTRODUCTION@#Chest physiotherapy (CPT) may benefit children aged below five years who suffer from lower respiratory tract infection (LRTI). However, its effects depend on the technique used. This study aimed to determine whether mechanical CPT using the LEGA-Kid® mechanical percussion device is superior to manual CPT in children with LRTI.@*METHODS@#Children aged five months to five years who were admitted and referred for CPT from January to April 2017 were randomised to either manual CPT or mechanical CPT with LEGA-Kid. Outcomes measured before intervention and two hours after intervention were respiratory rate (RR), oxygen saturation and modified Respiratory Distress Assessment Instrument (mRDAI) score.@*RESULTS@#All 30 enrolled patients showed significant reduction in post-intervention RR and mRDAI scores. There was an 8% reduction in RR for the manual CPT group (p = 0.002) and a 16.5% reduction in the mechanical CPT group (p = 0.0001), with a significantly greater reduction in the latter (p = 0.024). mRDAI scores decreased by 2.96 in the manual group (p = 0.0001) and 3.62 in the mechanical group (p = 0.002), with no significant difference between the groups. There was no significant improvement in oxygen saturation, and no adverse events were observed after CPT.@*CONCLUSION@#Children receiving both manual and mechanical CPT showed improvements in respiratory distress symptoms, with no adverse effects. A combined strategy of nebulised hypertonic saline followed by CPT for LRTI removes airway secretions and results in improvements in moderately severe respiratory distress. The LEGA-Kid mechanical CPT method is superior to manual CPT in reducing the RR.

Progress on the relationship between lower respiratory tract microbiota and lower respiratory tract diseases in children / 国际儿科学杂志

The lower respiratory tract of healthy children exists microbiota, not sterile.The microbiota is symbiotic with children and plays a role in nutrition absorption, vitamin synthesis, metabolism of foreign substances and immune regulation, to maintain the health of children′s lower respiratory tract.The disturbance of lower respiratory tract microbiota would lead to some lower respiratory tract diseases or aggravate the occurrence and development of diseases.This paper reviews the research progress in the sources and detection methods of lower respiratory tract microbiota, the characteristics of lower respiratory tract microbiota in healthy children, and the relationship between lower respiratory tract microbiota and lower respiratory tract diseases in children, to provide help for more accurate diagnosis and treatment of lower respiratory diseases in children.

Epidemiological study of respiratory syncytial virus-associated acute lower respiratory tract infection in hospitalized children in Shanghai / 中华传染病杂志

Objective:To investigate the epidemiological characteristics of hospitalized children with respiratory syncytial virus (RSV)-associated acute lower respiratory tract infection (ALRTI), and to analyzed the risk factors for severe infection.Methods:The epidemiological and clinical data of hospitalized children with ALRTI and positive RSV test from Children′s Hospital of Fudan University from January 2013 to December 2018 were retrospectively analyzed.The hospitalized children from October 2016 to November 2017 were selected by random singular sequence and divided into severe infection group and non-severe infection group. The clinical data of the two groups were compared. Multivariate logistic regression analysis was used to analyze the risk factors of severe RSV-associated ALRTI.Results:A total of 34 192 hospitalized children were diagnosed with ALRTI, and 8 113(23.73%) children were positive for respiratory tract viruses, including 4 028(11.78%) children with RSV infection, which was higher than other common respiratory tract viruses. Among the 4 028 RSV-positive children, 2 550(63.31%) were under six months of age, 3 623(89.95%) were under two years of age. The detection rates of RSV in spring, summer, autumn and winter were 6.47%(553/8 551), 2.46%(176/7 161), 12.85%(1 042/8 111) and 21.77%(2 257/10 369), respectively. In 347 hospitalized children with RSV-associated ALRTI, 54 cases were severe cases. Multivariate logistic regression analysis showed that RSV-positive patients complicated with respiratory diseases ( Z=3.43), cardiovascular diseases ( Z=4.96), non-exclusive breast-feeding ( Z=-1.97) and premature birth ( Z=-1.98) were independent risk factors for severe RSV-associated ALRTI (all P<0.050). Conclusions:RSV is the most important and common viral pathogen in hospitalized children with ALRTI in Shanghai, and infants under six months of age are the most susceptible to RSV. RSV patients complicated with respiratory diseases, cardiovascular diseases, non-exclusive breast-feeding and premature birth are more likely to develope severe RSV-associated ALRTI.

Microbiota pulmonar y el eje intestino-pulmón

RESUMEN Introducción: A la luz de los conocimientos más recientes, es trascendente enfatizar el potencial papel que desarrolla la microbiota intestinal, a través del eje intestino-pulmón, con la microbiota pulmonar. Objetivo: Actualizar criterios acerca de la microbiota pulmonar en sujetos sanos y su relación con el eje intestino-pulmón. Métodos: Se revisaron publicaciones en español e inglés en PubMed, Google Scholar, ScIELO, desde enero 2010-mayo 2020, se usaron los términos: microbiota pulmonar, microbiota vías respiratorias inferiores, eje intestino-pulmón, microbiota pulmonar e inmunidad y probióticos de nueva generación. Análisis e integración de la información: Se exponen argumentos relacionados con la presencia de microbiota comensal residente en el pulmón formada por bacterias, hongos y virus como integrantes de la comunidad microbiana. Papel del eje intestino-pulmón y su participación en modulación inmune. Se describen rasgos de la microbiota pulmonar, su biomasa, diversidad, y filos integrantes. Se resumen investigaciones en animales. Se destaca valor de la nueva tecnología de secuenciación gen 16S del ARNr para estudio e identificación. Consideraciones finales: El pulmón era considerado órgano estéril. Aquí se documenta la presencia de microbiota comensal residente en el pulmón, de gran diversidad, se postulan los mecanismos del eje intestino-pulmón y su papel en la modulación de la inmunidad pulmonar y valor diagnóstico en enfermedades del tracto respiratorio inferior. Se enfatiza el uso futuro de probióticos de nueva generación como moduladores de la microbiota pulmonar.

ABSTRACT Introduction: In the light of the most recent knowledge, it is important to emphasize the potential role played by the gut microbiota, through the gut-lung axis, with the lung microbiota. Objective: Update the criteria about the lung microbiota in healthy subjects and its relationship with the gut-lung axis. Methods: Publications in Spanish and English were reviewed in PubMed, Google Scholar, ScIELO, from January 2010 to May 2020; the following terms were used: lung microbiota, lower respiratory tract microbiota, gut-lung axis, lung microbiota and immunity and next- generation probiotics. Analysis and integration of information: Arguments related to the presence of commensal microbiota resident in the lung formed by bacteria, fungi and viruses as members of the microbial community are presented. Role of the gut-lung axis and its participation in immune modulation. Features of the lung microbiota, its biomass, diversity, and component phylums are described. Researches in animals are summarized. The value of the new 16S gene sequencing technology of rRNA for study and identification is highlighted. Final considerations: The lung was considered a sterile organ. Here the presence of resident commensal microbiota of great diversity in the lung is documented; the mechanisms of the gut-lung axis and its role in the modulation of lung immunity and diagnostic value in diseases of the lower respiratory tract are stated. The future use of next-generation probiotics as modulators of the lung microbiota is emphasized.

The effect of recombinant human interferon α1b treatment of infants hospitalized with lower respiratory tract infection on subsequent wheezing

Abstract Objective: To investigate the impact of recombinant human interferon α1b (rhIFNα1b) treatment in infants hospitalized with lower respiratory tract infections on subsequent wheezing. Methods: The clinical data of infants (n = 540) with viral pneumonia, wheezy bronchitis, or bronchiolitis hospitalized in 19 Chinese hospitals from June 2009 to June 2015 were retrospectively analyzed. The parameters relevant to wheezing episodes within the last year were collected by telephone and questionnaires. The rhIFNα1b treatment group (n = 253) and control group (n = 287) were compared in terms of wheezing episodes within the last year. Moreover, the wheezing group (95 cases) and non-wheezing group (445 cases) were compared. Results: Out of 540 cases, 95 (17.6%) experienced wheezing episodes, 13.8% (35/253) cases treated with rhIFNα1b, and 20.9% (60/287) cases without rhIFNα1b experienced wheezing episodes within the last year. The rhIFNα1b treatment significantly improved wheezing episodes within the last year, compared with the control peers (p = 0.031). Single-factor regression showed statistically significant differences between the wheezing and non-wheezing groups in terms of age, rhIFNα1b use, childhood and family history of allergy, housing situation, and feeding history (p < 0.05). Binary logistic regression showed a childhood history of allergy (OR = 2.14, p = 0.004), no rhIFNα1b use (OR = 1.70, p = 0.028), and living in a crowded house (OR = 1.92, p = 0.012) might be risk factors of subsequent wheezing. Accordingly, breastfeeding (OR = 0.44, p = 0.008) and hospitalization age of 1-year-old (OR = 0.58, p = 0.024) were protective factors. Conclusions: Early use of rhIFNα1b in infants hospitalized with lower respiratory tract infections and breastfeeding could prevent subsequent wheezing. Living in a crowded house could promote subsequent wheezing.

Application of next-generation sequencing technology in pathogen detection of lower respiratory tract infection in children / 中华实用儿科临床杂志

Next-generation sequencing (NGS), also known as high-throughput sequencing, is more efficient compared with Sanger sequencing that has become the standard method of clinical DNA sequencing, and can obtain a large amount of information in a relatively short time at a lower cost.NGS has broad prospects in such aspects as diagnosing the pathogen of lower respiratory tract infection in children, identifying the pathogen of cross-infection in hospital, drug resistance research and vaccine development.It is still worth conducting further studies on the approach to improve the specificity and sensitivity of diagnosis and to optimize NGS.

Clinical study of acute lower respiratory tract infection caused by respiratory syncytial virus in neonates / 中华实用儿科临床杂志

Objective:To investigate the clinical characteristics of acute lower respiratory tract infection (ALRTI) in neonates caused by respiratory syncytial virus (RSV), and to analyze the factors associated with the severe infection.Methods:Clinical data of 399 ALRTI neonates with positive nucleic acids or antigen of RSV admitted to Shenzhen Children′s Hospital from January 2014 to December 2020 were retrospectively analyzed for their clinical cha-racteristics.They were divided into mild-to-moderate group and severe group according to the severity index (SI), and the clinical data of the 2 groups were compared.Relevant factors of severe ALRTI of RSV in neonates were analyzed by multivariate Logistic regression. Results:(1) A total of 399 ALRTI neonates with RSV infection were included, involving 239 males (59.9%) and 160 females (40.1%) with a male-to-female ratio of 1.49∶1.00.There were 349 cases (87.5%) and 50 cases (12.5%) in the mild-to-moderate group and severe group, respectively.The disease mainly occurred from March to October.(2) There were significant differences in the preterm delivery [15 cases (4.3%) vs.9 cases (18.0%)], low birth weight [11 cases (3.2%) vs.6 cases (12.0%)], previous hospitalization history [12 cases (3.4%) vs.5 cases (10.0%)], and breastfeeding [167 cases (47.9%) vs.16 cases (32.0%)] between the mild-to-moderate group and severe group ( χ2=14.524, 8.394, 4.616 and 4.426, respectively, all P<0.05). (3) There were significant differences in fever [78 cases (22.4%) vs.18 cases (36.0%)], shortness of breath [156 cases (44.7%) vs.36 cases (72.0%)], poor appetite [48 cases (13.8%) vs.15 cases (30.0%)], wheezing [20 cases (5.7%) vs.10 cases (20.0%)], cyanosis [30 cases (8.0%) vs.16 cases (32.0%)] and mental status (irritability/malaise) [20 cases (5.7%) vs.8 cases (16.0%)], and duration of cough[(8.1±2.6) days vs.(9.4±2.9) days ] between the mild-to-moderate group and severe group ( χ2=4.460, 13.057, 8.682, 12.806, 23.486 and 7.068, t=-3.054, all P<0.05). Moist rales in the lungs [29 cases (58.0%) vs.114 cases (32.7%)] and three concave signs [14 cases (28.0%) vs.20 cases (5.7%)] were commonly found in the severe group, while pulmonary phlegm sounds [168 cases (48.1%) vs.14 cases (28.0%)]was commonly found in the mild-to-moderate group, and the differences were statistically significant ( χ2=12.208, 27.823 and 7.149, respectively, all P<0.05). (4) Multifactorial analysis showed that premature delivery was an independent risk factor for the development of severe ALRTI caused by RSV in neonates ( OR=3.717, 95% CI: 1.257-10.987), and shortness of breath ( OR=2.216, 95% CI: 1.061-4.629), cyanosis ( OR=3.621, 95% CI: 1.638-8.004) and three concave signs ( OR=2.688, 95% CI: 1.077-6.711) may be early warning factors for the severe condition. Conclusions:Preterm infants with RSV infection are prone to develop into severe disease, and neonates with RSV infection with shortness of breath, cyanosis and three concave signs as symptoms of severe infection should be well concerned for a close monitoring.

Phenotypic and genotypic characterization of plasmid-mediated AmpC beta-lactamases in enteric Gram-negative bacteria from patients with lower respiratory tract infections in a tertiary hospital, southwest Nigeria

Background: AmpC or class C or group 1 beta lactamases are class C cephalosporinases that hydrolyse a wide variety of beta-lactam antibiotics including alpha methoxy beta-lactams (cefoxitin), narrow and broad spectrum cephalosporins. This study was conducted to characterize plasmid-mediated AmpC producing enteric Gram- negative bacteria from patients with lower respiratory tract infections in Obafemi Awolowo University Teaching Hospital Complex (OAUTHC) Ile Ife, Osun State, Nigeria Methodology: A total of 149 patients with clinical features of lower respiratory tract infections (LRTI) were selected by simple random sampling for the study. All Gram-negative isolates recovered from standard microbiological cultures of respiratory specimens of these patients were tested against cefoxitin, third generation cephalosporins (3GCs), and other antibiotics using the disc diffusion AST method, and also screened for production of AmpC beta-lactamases phenotypically by the CLSI method. Plasmid DNA extraction was carried out on twenty-nine cefoxitin-resistant selected isolates using the Kado and Lin method, while genotypic detection of plasmid-mediated AmpC gene was carried out by the polymerase chain reaction (PCR) assay. Results: The results showed that 204 (43.3%) of 471 isolates recovered from the 149 selected patients were resistant to 3GC in the AST assay, among which 121 (59.3%) were resistant to cefoxitin, and 189 of the 471 isolates (40.1%) were AmpC producers. The AmpC producers concurrently showed multiple resistance pattern to other antibiotics tested in this study. Ninety six percent of the 29 selected isolates for plasmid analysis contained plasmids, 45% of which amplified positive on PCR for CMY, 38% for FOX, and 31% for ACC types of AmpC genes. Conclusion: This study showed a high degree of antibiotic resistance among enteric Gram-negative bacteria recovered from patients with LRTIs, as well as high degree of plasmid-encoded AmpC genes responsible for this high antibiotic resistance among the isolates. Proper antibiotic policy and regulation are required to limit the spread of plasmid mediated AmpC ß-lactamase

Molecular epidemiology of Pseudomonas aeruginosa isolated from lower respiratory tract of ICU patients / Epidemiologia molecular de Pseudomonas aeruginosa isolada em pacientes com infecções do trato respiratório inferior admitidos em UTI

Lower respiratory tract infections (LRTIs) caused by Pseudomonas aeruginosa are the most common infection among hospitalized patients, associated with increased levels of morbidity, mortality and attributable health care costs. Increased resistant Pseudomonas worldwide has been quite meaningful to patients, especially in intensive care unit (ICUs). Different species of Pseudomonas exhibit different genetic profile and varied drug resistance. The present study determines the molecular epidemiology through DNA fingerprinting method and drug resistance of P. aeruginosa isolated from patients with LTRIs admitted in ICU. A total of 79 P. aeruginosa isolated from patients with LRTIs admitted in ICU were characterized by Restriction Fragment Length Polymorphism (RFLP), Random Amplified Polymorphic DNA (RAPD) and Repetitive Extrapalindromic PCR (REP-PCR). Antibiotic resistance was determined by minimum inhibitory concentration (MIC) assay while MDR genes, viz, blaTEM, blaOXA, blaVIM, blaCTX-M-15 were detected by polymerase chain reaction (PCR). Of the 137 Pseudomonas sp isolated from ICU patients, 57.7% of the isolates were reported to be P. aeruginosa. The overall prevalence of P. aeruginosa among the all included patients was 34.5%. The RAPD analysis yielded 45 different patterns with 72 clusters with 57% to 100% similarity level. The RFLP analysis yielded 8 different patterns with 14 clusters with 76% to 100% similarity level. The REP PCR analysis yielded 37 different patterns with 65 clusters with 56% to 100% similarity level. There was no correlation among the different DNA patterns observed between the three different methods. Predominant of the isolates (46.8%) were resistant to amikacin. Of the 79 isolates, 60.8% were positive for blaTEM gene and 39.2% were positive for blaOXA gene. P. aeruginosa was predominantly isolated from patients with LRTIs admitted in ICU. The difference in the similarity level observed between the three DNA fingerprinting methods indicates that there is high inter-strain variability. The high genetic variability and resistance patterns indicates that we should continuously monitor the trend in the prevalence and antibiotic resistance of P. aeruginosa especially in patients with LRTIs admitted in ICU.

Infecções do trato respiratório inferior (ITRIs) são as infecções mais comuns entre pacientes internados em unidade de terapia intensiva (UTI). Pseudomonas aeruginosa é a causa mais comum de ITRIs e está associada ao aumento da mortalidade. Diferentes espécies de Pseudomonas exibem diferentes perfis genéticos e resistência variada as drogas. O presente estudo determina a epidemiologia molecular através do método de fingerprinting de DNA e resistência as drogas de P. aeruginosa isoladas de pacientes com LTRIs internados em UTI. Um total de 79 P. aeruginosa isoladas de pacientes com ITRIs internados em UTI foram caracterizados por Polimorfismo de Comprimento de Fragmentos de Restrição (RFLP), DNA Polimórfico Amplificado ao Acaso (RAPD) e PCR Extrapalindrômico Repetitivo (REP-PCR). A resistência aos antibióticos foram determinadas pelos ensaios de concentrações inibitória mínima (MIC), enquanto os genes MDR, blaTEM, blaOXA, blaVIM, blaCTX-M-15 foram detectados pela reação em cadeia da polimerase (PCR). Das 137 Pseudomonas sp isoladas de pacientes de UTI, 57,7% dos isolados foram relatados como P. aeruginosa. A prevalência geral de P. aeruginosa entre os pacientes incluídos foram de 34,5%. A análise RAPD renderam 45 padrões diferentes com 72 clusters com nível de similaridade de 57% a 100%. A análise RFLP renderam 8 padrões diferentes com 14 clusters com 76% a 100% de similaridade. A análise de PCR do REP produziram 37 padrões diferentes com 65 clusters com nível de similaridade de 56% a 100%. Não houveram correlações entre os diferentes padrões de DNA observados entre os três diferentes métodos. Predominantes dos isolados (46,8%) eram resistentes à amicacina. Dos 79 isolados, 60,8% foram positivos para o gene blaTEM e 39,2% foram positivos para o gene blaOXA. P. aeruginosa foi predominantemente isolado de pacientes com ITRIs internados em UTI. A diferença no nível de similaridade observado entre os três métodos de fingerprinting do DNA indica que há alta variabilidade inter-strain. A alta variabilidade genética e os padrões de resistência indicam que devemos monitorar continuamente a tendência na prevalência e resistência a antibióticos de P. aeruginosa, especialmente em pacientes com ITRIs internados em UTI.

Frequency of nutritional rickets, its clinicobiochemical profile and its relationship to the lower respiratory tract infections in indoor patients from 2 to 60 months of age

Background: Frequency of nutritional rickets, its clinicobiochemical profile and its relationship to the lower respiratory tract infections in indoor patients from 2 to 60 months of age.Methods: Children aged 2 to 60 months admitted for the first time were included in the study and divided into two groups i.e. with and without clinical signs of rickets. Disease profile was studied in both groups. Incidence of lower respiratory tract infection was compared between two groups.  Children with clinicoradiological signs of rickets were also investigated for biochemical abnormalities.Results: During the one year study period a total of 393 children were admitted, 65 were found to have rickets constituted as study group and 328 were without rickets were included the controls. Rickets incidence was 16.5% of which majority (74.6%) were males and most rachitic children (64.6%) were below six months of age. Acute lower respiratory tract infection (64.6%) was commonest in study group and acute gastroenteritis (24.4%) in the controls. The rate of ALRTI was nearly three times in study group.  Frontal bossing (67.7%) was most common sign of rickets and increased alkaline phosphatase (93.8%) was the commonest biochemical abnormality.Conclusions: Nutritional rickets, a multifactorial disease, is easily preventable. The present study has revealed the high incidence of rickets i. e., 16.5% and also show the strong statistically significant association of nutritional rickets with acute lower respiratory tract infections.