Lower Respiratory Tract Infections In Children Research Articles

Lung function at 10 yr is not impaired by early childhood lower respiratory tract infections

The causal relationship between lower respiratory tract infections (LRIs) in early life and reduced lung function later in childhood is unsettled. Therefore, we assessed whether LRIs the first 2 yr of life influenced lung function development from birth to school age. In the prospective Oslo birth cohort, 'the Environment and Childhood Asthma (ECA) study' lung function was measured at birth in 802 infants by tidal flow volume loops and in 664 infants by passive respiratory mechanics and half yearly questionnaires, including LRI questions, were completed until 2 yr of age. The present study includes 607 children with information about LRIs the first 2 yr of life and successfully forced expiratory flow (FEF) volume measurements at the 10-yr follow-up assessment. At 10 yr of age, FEF at 50% of forced vital capacity (FEF(50)) (mean 95% confidence interval) was reduced in children with at least one bronchiolitis (85.0, 80.6-89.5, p = 0.020) or bronchitis (86.2, 82.6-89.8, p = 0.030) or > or =3 LRIs (83.4, 78.1-88.8, p = 0.017) when compared with no LRIs (90.6, 88.8-92.5) by 2 yr of life. The effects were significant in girls only when stratifying for gender. Among girls with later bronchiolitis compliance of the respiratory system (3.64, 3.17-4.10 vs. 4.18, 3.98-4.37, p = 0.031) and the ratio of time to peak tidal expiratory flow to total expiratory time (t(PTEF)/t(E)) measured at birth was significantly reduced (0. 26, 0.23-0.29 vs. 0.32, 0.30-0.33, p = 0.005) when compared with children with no LRIs. Change in lung function from birth (by t(PTEF)/t(E)) to 10 yr of age was not significantly associated with LRIs the first 2 yr of life, and LRIs by 2 yr of life were not significantly associated with lung function at 10 yr of age in regression analyses including lung function at birth and other possible predictors of lung function at 10 yr. In our study, LRIs during the first 2 yr of life did not impair lung function development from birth until 10 yr of age.

Rhinovirus Associated With Severe Lower Respiratory Tract Infections in Children

Rhinovirus is a respiratory virus most typically associated with the common cold and asthma exacerbations, and has not traditionally been considered to play a major role in severe lower respiratory tract infections (LRTIs). As part of a surveillance program for respiratory pathogens of public health importance, children consecutively admitted to intensive care for LRTI at a large tertiary children's hospital were tested with polymerase chain reaction for 11 respiratory viruses and Mycoplasma pneumoniae from February 21 to October 31, 2007; 43 cases were enrolled and rhinovirus was the most frequently detected pathogen, with 21 (49%) positive. Rhinovirus cases frequently were young (median age, 1.4 years [range, 44 days-15 years]), hospitalized for pneumonia (10; 48%), had chronic underlying illnesses (15; 71%), had abnormal chest radiographs (18; 86%), required mechanical ventilation (12; 57%), and had prolonged hospitalization (median length, 7 days [range, 1-29 days]). Coinfection with other viruses or bacteria was common (10; 47%). Rhinovirus may be associated with more severe LRTI in children than previously reported, particularly in the noninfluenza, nonrespiratory syncytial virus season.

Recent diarrhoeal illness and risk of lower respiratory infections in children under the age of 5 years

Background Children in low-income settings suffering from frequent diarrhoea episodes are also at a high risk of acute lower respiratory infections (ALRI). We explored whether this is due to common risk factors for both conditions or whether diarrhoea can increase the risk of ALRI directly.Methods We used a dynamic time-to-event analysis of data from two large child studies in low-income settings in Ghana and Brazil, with the cumulative diarrhoea prevalence over 2 weeks as the exposure and severe ALRI as outcome. The analysis was adjusted for baseline risk of ALRI and diarrhoea, seasonality and age.Results The child population from Ghana had a much higher risk of diarrhoea, malnutrition and death than the children in Brazil. In the data from Ghana, every additional day of diarrhoea within 2 weeks increased the risk of ALRI by a factor of 1.08 (95% CI 1.00–1.15). In addition, we found a roughly linear relationship between the number of diarrhoea days over the last 28 days and the risk of ALRI. In the Ghana data, 26% of ALRI episodes may be due to recent exposure to diarrhoea. The Brazilian data gave no evidence for an association between diarrhoea and ALRI.Conclusion Diarrhoea may contribute substantially to the burden of ALRI in malnourished child populations.

Integrin αvβ1 promotes infection by human metapneumovirus

Human metapneumovirus (hMPV) is a recently described paramyxovirus that causes lower respiratory infections in children and adults worldwide. The hMPV fusion (F) protein is a membrane-anchored glycoprotein and major protective antigen. All hMPV F protein sequences determined to date contain an Arg-Gly-Asp (RGD) sequence, suggesting that F engages RGD-binding integrins to mediate cell entry. The divalent cation chelator EDTA, which disrupts heterodimeric integrin interactions, inhibits infectivity of hMPV but not the closely related respiratory syncytial virus (RSV), which lacks an RGD motif. Function-blocking antibodies specific for alphavbeta1 integrin inhibit infectivity of hMPV but not RSV. Transfection of nonpermissive cells with alphav or beta1 cDNAs confers hMPV infectivity, whereas reduction of alphav and beta1 integrin expression by siRNA inhibits hMPV infection. Recombinant hMPV F protein binds to cells, whereas Arg-Gly-Glu (RGE)-mutant F protein does not. These data suggest that alphavbeta1 integrin is a functional receptor for hMPV.

Lifecourse predictors of adult respiratory function: results from the Newcastle Thousand Families Study

Background:Impaired development in utero is suggested to increase the risk of poor respiratory health in adulthood, although a consensus has not been reached. A possible explanation for discrepancies between previous...

Vitamin A for preventing acute lower respiratory tract infections in children up to seven years of age

Vitamin A supplements are effective for preventing diarrhoea. There are theoretical reasons it might also be effective for acute lower respiratory tract infections (LRTIs), also very common in children, especially in low income countries. To assess the effectiveness and safety of vitamin A for preventing acute LRTIs in children up to seven years of age. We searched the Cochrane Central Register of Controlled Trials (CENTRAL) (The Cochrane Library 2007, Issue 2); MEDLINE (1966 to July 2007); EMBASE (1974 to July 2007); and the Chinese Biomedicine Database (CBM) (1976 to July 2007). Randomised controlled trials (RCTs) that assessed the effectiveness of vitamin A in the prevention of acute LRTI in children up to seven years of age. The review authors independently extracted data and assessed trial quality. Study authors were contacted for additional information. Most studies found no significant effect of vitamin A on the incidence of acute LRTI, or prevalence of symptoms of acute LRTI. Vitamin A caused an increased incidence of acute LRTI in one study; an increase in cough and fever; and increased symptoms of cough and rapid breathing in two others. Three reported no differences and no protective effect of vitamin A. Two studies reported that vitamin A significantly reduced the incidence of acute LRTI with children with poor nutritional status or weight, but increased it in normal children. This unexpected result is outside our current understanding of the use of vitamin A for preventing acute LRTIs. Accordingly, vitamin A should not be given to all children to prevent acute LRTIs. There is evidence for vitamin A supplements to prevent acute LRTIs in children with low serum retinol or those with a poor nutritional status.

Immune and metabolic characteristics of children with recurrent respiratory diseases and efficacy of complex differentiated improving using seleksen and ascorbic acid

This comparative clinical and immunological trial investigated clinical efficacy of Seleksen combined with ascorbic acid as a part of complex rehabilitation of children with recurrent respiratory diseases in sanatorium pre-school child care settings. We assessed serum levels of IgA, IgG, IgM, IgE, and interleukin-8, leucocyte luminol-induced chemiluminescence, secretory IgA level in saliva, erythrocyte glutathione peroxidase activity, serum superoxide dismutase activity, serum concentrations of malone dialdehyde and diene conjugates. The follow-up period was 12 months. The complex rehabilitation with Seleksen and ascorbic acid led to clear improvement in clinical, immunological, and metabolic parameters. It allows significant reduction in rate of upper and particularly lower respiratory infections in children attending pre-school child care facilities. This therapy was the most effective in children with allergic respiratory diseases and recurrent tracheobronchitis.

Estimating the burden of disease attributable to indoor air pollution from household use of solid fuels in South Africa in 2000.

To estimate the burden of respiratory ill health in South African children and adults in 2000 from exposure to indoor air pollution associated with household use of solid fuels. World Health Organization comparative risk assessment (CRA) methodology was followed. The South African Census 2001 was used to derive the proportion of households using solid fuels for cooking and heating by population group. Exposure estimates were adjusted by a ventilation factor taking into account the general level of ventilation in the households. Population-attributable fractions were calculated and applied to revised burden of disease estimates for each population group. Monte Carlo simulation-modelling techniques were used for uncertainty analysis. South Africa. Black African, coloured, white and Indian children under 5 years of age and adults aged 30 years and older. Mortality and disability-adjusted life years (DALYs) from acute lower respiratory infections in children under 5 years, and chronic obstructive pulmonary disease and lung cancer in adults 30 years and older. An estimated 20% of South African households were exposed to indoor smoke from solid fuels, with marked variation by population group. This exposure was estimated to have caused 2,489 deaths (95% uncertainty interval 1,672 - 3,324) or 0.5% (95% uncertainty interval 0.3 - 0.6%) of all deaths in South Africa in 2000. The loss of healthy life years comprised a slightly smaller proportion of the total: 60,934 DALYs (95% uncertainty interval 41,170 - 81,246) or 0.4% of all DALYs (95% uncertainty interval 0.3 - 0.5%) in South Africa in 2000. Almost 99% of this burden occurred in the black African population. The most important interventions to reduce this impact include access to cleaner household fuels, improved stoves, and better ventilation.

Quantification of human bocavirus in lower respiratory tract infections in China

A quantitative PCR method was established to quantify human bocavirus (HBoV) genomic copies in clinical specimens from children with lower respiratory tract infections (LRTI) in China. A total of 257 respiratory tract specimens were tested, and 7 (2.7%) of these (all sputum samples) were positive, with genomic copies that ranged from 8.0 × 103 to 8.0 × 109 in the samples. The main clinical symptom of patients who were positive for HBoV DNA was a pneumonia-like syndrome represented by high fever and cough. Our results suggest that HBoV may be an important etiological agent of LRTI in children in China.

Reducing the global burden of acute lower respiratory infections in children: the contribution of new diagnostics

Acute lower respiratory infections (ALRIs) are the primary killer of children in developing countries. Many children with ALRIs are not properly diagnosed, and overuse of antibiotics has led to increasing drug resistance. The introduction of simple and widely accessible diagnostic tests could significantly reduce deaths among children with ALRIs and reduce the inappropriate use of antibiotics.

The Role of Chest X-Ray in the Diagnosis of Community Acquired Pneumonia in Children: A Systematic Review

For many years the gold standard in diagnosing pneumonia has been the chest x-ray, both in clinical practice and for research purposes. The objective of this review was to examine the evidence to determine the role of chest x-ray in the diagnosis of pneumonia. A comprehensive literature search was conducted and abstracts were obtained from articles that, judged by their titles, bore relevance to the subject in question. Articles were selected for review based on their abstracts. Articles were subsequently reviewed, appraised and results were presented by grading evidence as Level I, II or III. Even the best available evidence failed to demonstrate improved outcome with the addition of chest radiography in ambulatory acute lower-respiratory infection in children. There is little evidence to justify the routine use of chest radiography in the diagnosis of pneumonia in children, but more research is needed to explore the potential benefit of chest radiography in specific clinical scenarios. Keywords: Pneumonia, chest x-ray/radiograph, diagnosis

Human Metapneumovirus Fusion Protein Vaccines That Are Immunogenic and Protective in Cotton Rats

Human metapneumovirus (hMPV) is a recently described paramyxovirus that is a major cause of upper and lower respiratory infection in children and adults worldwide. A safe and effective vaccine could decrease the burden of disease associated with this novel pathogen. We previously reported the development of the cotton rat model of hMPV infection and pathogenesis (J. V. Williams et al., J. Virol. 79:10944-10951, 2005). We report here the immunogenicity of an hMPV fusion (F) protein in this model. We constructed DNA plasmids that exhibited high levels of expression of hMPV F in mammalian cells (DNA-F). These constructs were used to develop a novel strategy to produce highly pure, soluble hMPV F protein lacking the transmembrane domain (FDeltaTM). We then immunized cotton rats at 0 and 14 days with either control vector, DNA-F alone, DNA-F followed by FDeltaTM protein, or FDeltaTM alone. All groups were challenged intranasally at 28 days with live hMPV. All three groups that received some form of hMPV F immunization mounted neutralizing antibody responses and exhibited partial protection against virus shedding in the lungs compared to controls. The FDeltaTM-immunized animals showed the greatest degree of protection (>1,500-fold reduction in lung virus titer). All three immunized groups showed a modest reduction of nasal virus shedding. Neither evidence of a Th2-type response nor increased lung pathology were present in the immunized animals. We conclude that sequence-optimized hMPV F protein protects against hMPV infection when delivered as either a DNA or a protein vaccine in cotton rats.

The Research for Incidence of Klebsialla Pneumonia Infection in Acute lower Respiratory Infection in Children

目的 了解儿童急性下呼吸道感染肺炎克雷白菌(Klebsialla Pneumonia)(KPN)感染状况和特点.方法 采用敏感性较好培养方法 对288例各年龄组下呼吸道感染住院儿童进行痰培养.结果 共发现肺炎克雷白菌(KPN)阳性58例,总感染率(20.14%),其中89例肺炎中,KPN阳性34例(38.21%),128例毛细支气管炎KPN阳性19(14.85%),71例支气管炎KPN阳性5例(7.05%).结论 肺炎克雷白菌(KPN)是儿童急性下呼吸道感染的重要病原,其在儿童急性感染中占有重要地位,在毛细支气管炎,支气管肺炎,支气管炎中作用值得重视.且KPN多产生ESBL,对儿科常用药耐药率高.对亚胺培南,氧哌嗪/他唑巴坦敏感。

Hemoglobin level as a risk factor for lower respiratory tract infections

This prospective study was conducted to evaluate the role of hemoglobin level, as a risk factor for Lower Respiratory Tract Infections in children (LRTI). 100 children who came to the outpatient department for LRTI were included in the study. Age and sex-matched 100 children, not having any respiratory illness, were taken as control. They were subjected to complete blood count (CBC),C-reactive protein estimation (CRP), Mantoux test and X-ray chest. Peripheral smear, serum ferritin and serum iron binding capacity were done for all anemic children. Results. Radiological evidence of pneumonia was present in 63 children(63%).Hyper inflated lungs were seen in 27 (27%). Mantoux was positive in 22 children (22%) of study group and none among control group. CRP > 6 mg/L was noted in 45 children (45%) of study group and 14 (14%) of control group. Seventy four of study group (74 %) and 33 of control group (33%) had anemia. Of the anemic children, 60 (60%) had iron deficiency,10 (10%) chronic inflammation and 4 (4%) had hemolytic anemia. These values were 30 (30%), 2 (2%) and 1 (1%)respectively for control group. Low hemoglobin level due to whatever etiology, was a risk factor (p=0.000). Anemic children were 5.75 times more susceptible to LRTI compared to the control group. Prevention of anemia, due to whatever etiology, will reduce the incidence of LRTI.

Office pediatrics: current perspectives on the outpatient evaluation and management of lower respiratory infections in children

The outpatient evaluation and management of a child with lower respiratory infection (LRI) remain a challenge to clinicians worldwide. This update will discuss current problems and new developments in the outpatient evaluation and treatment of pediatric LRIs. The cause of pediatric LRIs remains partially defined. Mixed infections and 'unknown' organisms may be important sources of clinical illness. A wider incidence of atypical bacteria LRIs (notably Mycoplasma pneumoniae) in children is now recognized. Viral LRIs from rhinoviruses and human metapneumovirus are increasingly detected in children. Human metapneumovirus may compound the clinical severity of pediatric LRIs, specifically in combination with respiratory syncytial virus. Innovations in testing for viral LRIs offer a promising tool for the outpatient evaluation and management of pediatric LRIs. Neither clinical symptoms nor findings on chest radiographs can reliably distinguish children with bacterial LRIs from those with viral or atypical pathogens. The efficacy of outpatient antibiotic treatment of atypical bacteria LRIs remains unproven. Multiplex rapid viral testing may ultimately help to refine strategies for outpatient management. The outpatient treatment of viral LRIs remains limited to supportive care; the 'value' of bronchodilators, epinephrine, or corticosteroids for treatment of bronchiolitis is unconfirmed.

Human Metapneumovirus Infection in Hospitalized Children with Acute Respiratory Disease in Korea

Human metapneumovirus (hMPV) is a recently isolated virus, mostly associated with acute lower respiratory infection in children, of which symptoms are similar to those of respiratory syncytial virus (RSV) infection. The aim of our study was to determine the frequency of hMPV in hospitalized children with acute respiratory tract disease in Korea. Nasal aspirates from hospitalized children with respiratory infections under 15 yr old between December 2003 and February 2005 were included in the study. Each sample was analyzed for RSV, adenovirus, influenza virus A and B, and parainfluenza virus by indirect fluorescent assay (IFA). F-gene sequences were used for PCR for the detection and sequencing of hMPV. In total 381 samples, negative samples in which any viral pathogen could not be identified by IFA were 231 cases. hMPV was detected using reverse transcriptase-PCR (RT-PCR) in 28 of 231 (12.1%) children who were not infected with another respiratory viruses. The hMPV-infected children were diagnosed as having pneumonia, bronchiolitis, bronchial asthma exacerbation, croup, and upper respiratory tract infection. Most of the RT-PCR positive samples for hMPV were collected in winter season. These results suggest that hMPV may be a responsible pathogen causing acute respiratory tract infection in Korean children.

Economic impact of community-acquired and nosocomial lower respiratory tract infections in young children in Germany

Data on the economic burden of lower respiratory tract infections (LRTI) in young children are lacking in Germany. The objective of the cost-of-illness study was to estimate the economic impact of community-acquired LRTI and nosocomial LRTI as well as of infections due to respiratory syncytial virus (RSV), parainfluenza viruses (PIV) and influenza viruses (IV). The economic analysis is part of the PRIDE study, a prospective, multi-centre, population-based epidemiological study on the impact of LRTI in children aged 0 to 36 months in Germany. The analysis includes children with community-acquired infections (1329 cases treated as outpatients, 2039 cases treated as inpatients) and nosocomial infections (90 cases). Medical services consumed were generated by chart abstraction and parental expenses data by telephone interviews within four weeks after physician visit or hospitalisation. Costs were evaluated from following perspectives: third party payer, parent and society. Total costs for outpatient treatment are Euro 123 per LRTI case. Stratified by virus type, total costs per case are Euro 163 (RSV), Euro 100 (PIV) and Euro 223 (IV). Total costs per hospitalised LRTI case amount to Euro 2579. Stratified by virus type, total costs per case are Euro 2772 (RSV), Euro 2374 (PIV) and Euro 2597 (IV). Total costs per nosocomial case are Euro 2814. Economic burden due to LRTI is Euro 213 million annually. It is concluded that treatment of LRTI in children up to age three causes a considerable economic burden in Germany. Presented results are the first data describing the economic burden of LRTI in young children assessed by means of the incidence data for Germany. This cost-of-illness study provides basic data for further decision-making, focusing on the economic assessment of preventive strategies for RSV, PIV and IV infections.

Office pediatrics: current issues in lower respiratory infections in children

Recent estimates indicate that 1.9 million children worldwide die each year from acute respiratory illnesses, many of which are lower respiratory infections (LRIs). Global threats from indoor and outdoor air pollution, urban crowding, biologic weapons, and worldwide rapid transportation complicate our efforts to reduce the impact of LRI disease in children. As new strategies are developed to limit the spread of LRI disease in children, existing pathogens become more complex to treat and newer pathogens emerge as causes of clinical disease. Most LRI disease is managed in outpatient settings and remains a challenge to those who care for children. Atypical pathogens (notably mycoplasma pneumoniae) are now known to cause a wide spectrum of disease, and with more extensive complications than previously recognized. Available data suggest a rapid increase in S. pneumoniae resistance to penicillin and macrolides in many cases of community acquired pneumonia, which has resulted in shifts in outpatient (and inpatient) antibiotic treatment regimens. Human metapneumovirus (HMPV) is now recognized to cause LRI illness similar to respiratory syncytial virus (RSV) in infants and children. General strategies for the prevention of influenza infection are expanded to include many infants and young children, and are projected to significantly reduce morbidity and mortality from this key LRI pathogen. The spectrum of LRI pathogens--and the clinical illnesses caused by them--continues to change. Innovations in immunotherapy and vaccines will be instrumental to reducing the burden of LRI morbidity in infants and children worldwide in the future.

Current challenges in lower respiratory infections in children.

Lower respiratory infections threaten the health of children worldwide. Streptococcus pneumoniae remains the most common bacterial cause of lower respiratory infection in children, whereas viral pathogens dominate as a more common cause of lower respiratory infection illness in infants and children overall. The diagnosis and clinical management of lower respiratory infections pose challenges to pediatric health providers as new technology is developed and new pathogens emerge in the spectrum of clinical disease. Human metapneumovirus is now recognized as a cause of lower respiratory infection disease in children, and coronavirus has been linked to epidemics of severe acute respiratory syndrome. Respiratory syncytial virus continues to be a major source of viral lower respiratory infection illness in children and can lead to childhood asthma. Treatment for respiratory syncytial virus bronchiolitis depends largely on the severity of disease and the course of clinical symptoms. The diagnosis of bacterial lower respiratory infection disease remains a clinical challenge, but new methods to detect S. pneumoniae, or Chlamydia pneumoniae and Mycoplasma pneumoniae may facilitate the clinical management of these illnesses. As immunization against S. pneumoniae becomes more widely used, the complications of bacterial lower respiratory infections will diminish markedly. Future progress in the clinical management of lower respiratory infection diseases will entail improved methods of early diagnosis, broader options for treatment, and better defined clinical parameters for triage and follow-up of children with lower respiratory infections.

The study of nonbacterial pathogen of acute lower respiratory tract infection among younger children in Guangzhou

Objective To investigate the nonbacterial etiology of children's acute lower respiratory infection in Guangzhou. Methods Five kinds of pathogenic serum antibody were tested by ELISA and influenza virus was detected by fluorescence PCR. Results Among all 824 patients, the specific antibody for RSV were detected positive in 182 cases, for AdV in 70 cases ,for CBV in 37 cases, for MP in 135 cases and for CP in 60 cases respectively. The Flu V was detected 35 of 392 patients. The rate of infection with RSV, AdV in children less 3 years old was significant higher than those older 3 years old. The rate of infection with Flu V and MP in children older than 3 years old was significant higher than those less than 3 years old. Rsv ,Flu V and MP infection had a seasonal trend. Conclusions Viral infection was the most common cause of acute lower respiratory infection in children,.RSV is the most common pathogen, followed by MP. There is no evident of influenza virus outbreak. The children less than 3 year old are subject to infection with RSV and AdV while the children older 3 years old are subject to infection with influenza virus and MP.