Lower Respiratory Tract Infections Group Research Articles

Çocuk Servisinde Yatırılarak Tedavi Edilen Alt Solunum Yolu Enfeksiyonu Tanılı 0 – 36 Ay Arası Çocukların Vitamin A Ve Vitamin D Düzeylerinin Aynı Yaş Grubu Sağlıklı Çocuklar Ile Karşılaştırılması

Background Lower respiratory system infections are highly common in young children and may require inpatient treatment. Studies have shown that patients treated and followed up for lower respiratory system infections have low levels of vitamin A and Vitamin D. In our study, we aimed to determine whether the deficiencies of these vitamins are risk factors for the development of lower respiratory system infections by comparing the serum vitamin A and vitamin D levels of patients 0-36months with lower respiratory tract infection and healthy children. Materials and Method The study included 82 children who applied to pediatric outpatient clinic between February 1st 2020 and June 30th 2020 with lower respiratory tract infection between the age 0-36 months, who gave blood sample for determination of serum vitamin A and vitamin D levels. 58 healthy children who applied to the outpatient clinic for routine check-up were determined as the control group. Age, sex, height and weight of all children were recorded. Results The average vitamin D level of those in the lower respiratory tract infection group was found to be 15.96±7.49ng/ml and those in the healthy group had average vitamin D levels of 32.19±14.27 ng/ml, showing that the sick group had statistically significantly lower levels of vitamin D (p=0.0001). The average vitamin A level of those in the sick group was found to be 170.42±60.42 ng/ml, whereas those in the control group had average vitamin A levels of 284.42±71.2 ng/ml, which showed that those in the sick group had statistically significantly low levels of vitamin A (p=0.0001). Our study showed that there is a positive statistically meaningful correlation between the vitamin D variable and the vitamin A variable (r=0.432, p=0.0001). Conclusions Our study is the only study in the literature comparing both the vitamin A and vitamin D levels of patients with lower respiratory tract infection. Vitamin A and vitamin D levels of patients with lower respiratory tract infections are found to be lower compared to healthy children, therefore we predict that controlling the vitamin levels of such patient and giving the appropriate treatment when needed, will lower the morbidity and mortality caused by lower respiratory tract infections.

Risk factors and outcomes of lower respiratory tract infections after traumatic brain injury: a retrospective observational study.

Traumatic brain injury (TBI) is a public health problem with a high burden in terms of disability and death. Infections are a common complication, with respiratory infections being the most frequent. Most available studies have addressed the impact of ventilator-associated pneumonia (VAP) after TBI; therefore, we aim to characterize the hospital impact of a broader entity, lower respiratory tract infections (LRTIs). This observational, retrospective, single-center cohort study describes the clinical features and risk factors associated with LRTIs in patients with TBI admitted to an intensive care unit (ICU). We used bivariate and multivariate logistic regressions to identify the risk factors associated with developing LRTI and determine its impact on hospital mortality. We included 291 patients, of whom 77% (225/291) were men. The median (IQR) age was 38 years (28-52 years). The most common cause of injury was road traffic accidents 72% (210/291), followed by falls 18% (52/291) and assault at 3% (9/291). The median (IQR) Glasgow Coma Scale (GCS) score on admission was 9 (6-14), and 47% (136/291) were classified as severe TBI, 13% (37/291) as moderate TBI, and 40% (114/291) as mild TBI. The median (IQR) injury severity score (ISS) was 24 (16-30). Nearly 48% (141/291) of patients presented at least one infection during hospitalization, and from those, 77% (109/141) were classified as LRTIs, which included tracheitis 55% (61/109), ventilator-associated pneumonia (VAP) 34% (37/109), and hospital-acquired pneumoniae (HAP) 19% (21/109). After multivariable analysis, the following variables were significantly associated with LRTIs: age (OR 1.1, 95% CI 1.01-1.2), severe TBI (OR 2.7, 95% CI 1.1-6.9), AIS thorax (OR 1.4, 95 CI 1.1-1.8), and mechanical ventilation on admission (OR 3.7, 95% CI 1.1-13.5). At the same time, hospital mortality did not differ between groups (LRTI 18.6% vs. No LRTI 20.1%, p = 0.7), and ICU and hospital length of stay (LOS) were longer in the LRTI group (median [IQR] 12 [9-17] vs. 5 [3-9], p < 0.01) and (median [IQR] 21 [13-33] vs. 10 [5-18], p = 0.01), respectively. Time on the ventilator was longer for those with LRTIs. The most common site/location of infection in patients with TBI admitted to ICU is respiratory. Age, severe TBI, thoracic trauma, and mechanical ventilation were identified as potential risk factors. LRTI was associated with prolonged ICU, hospital stay, and more days on a ventilator, but not with mortality.

Evaluation of peak expiratory flow rate with severity of lower respiratory tract infection in children of Hadoti region

Background: Correlation of peak expiratory flow rate (PEFR) with severity of lower respiratory tract infection (LRTI) and comparison of PEFR with same age, sex, height and nutritional status of children of age group 7 to 18 years. Methods: This is a case control study in children in the age group of 7 to 18 years of both sexes suffering from LRTI admitted in department of paediatrics of a tertiary care government hospital of Hadoti region. The duration of study was October 2019 to September 2020. Group 1 (case group) comprised of children having LRTI, whereas group 2 (control group) comprised of healthy and asymptomatic children There were 250 children in each group and they were further categorized into 3 age groups of 7-10 years, 11-13 years and 14-18 years. The PEFR of LRTI group children was compared with control group children with the similar age, sex as well as the anthropometric measurements. Results: In LRTI group, the PEFR had significant difference from control group, in all three age groups (p&lt;0.0001). The study showed positive co-linear relationship between age, height, weight and BMI with PEFR in both males and females in LTRI and control groups. Conclusions: Effect of PEFR depends upon anthropometric measurements of children of different age group in both LRTI population and control population. In control group PEFR showed significant difference between boys and girls, but in LRTI group PEFR showed non-significant difference between boys and girl in their respective age groups.

Risk Factors for Lower Respiratory Tract Infection Associated With Tracheobronchial Foreign Body Aspiration in Children.

Tracheobronchial foreign body aspiration (TFBA) is a major cause of accidental death in children. Lower respiratory tract infection (LRTI) may be caused by TFBA, but there are few reports about LRTI associated with TFBA. This study collected TFBA cases in our hospital to analyze LRTI and determine its risk factors. A total of 194 children who underwent tracheobronchial foreign body (TFB) extraction in The Children's Hospital of Zhejiang University School of Medicine from June 2019 to April 2020 were enrolled. CT chest is routinely used in the workup of suspected airway FB at our institution to evaluate for patients, a FB was already highly suspected. The retention time was defined as from the time of TFB inhalation or presentation (if there was no history of TFBA) to the time of TFB removal. General characteristics including weight, clinical symptoms, operative records, cervicothoracic CT, retention time, type of TFB and postoperative hospitalization time were collected. Chi-square tests, rank sum tests and multivariate logistic regression analyses were performed. The incidence of LRTI was 46.6%, 68.6%, and 68.6% when the retention time was within 24 hours, between 24 hours and up to 1 week and more than 1 week, respectively. Postoperative hospitalization time of LRTI group was significantly longer than that of non-LRTI group. Findings for cervicothoracic CT as pneumonia, emphysema, atelectasis meant more serious clinical manifestations and the retention time was longer in the LRTI group than in the non-LRTI group. There was a positive correlation between the retention time of a TFB and LRTI in multivariate logistic regression analysis. The incidence of LRTI caused by TFBA is high. LRTI is association with longer postoperative hospitalization time. The TFB retention time is an independent risk factor for LRTI. If a patient presents with significant LRTI symptoms, a course of steroids and antibiotics maybe a safer approach rather than proceeding immediately with bronchoscopic removal.

Characteristics and impact of postoperative surgical site infection on increased antibiotic duration among patients with laryngocarcinoma: a retrospective cohort study.

Whether increased antibiotic duration is necessary for surgical site infection (SSI) in patients after neck surgery is unclear. We investigated the characteristics of SSI, and the impact of SSI on increased antibiotic duration among patients with laryngocarcinoma (LC). A retrospective cohort study including consecutive LC patients ≥18 years, undergoing surgery without remote metastasis was conducted from October 2015 to February 2022 in the Department of Otolaryngology-Head and Neck Surgery, Chengdu Second People's Hospital. SSI was defined according to current guidelines. Patients were stratified into 3 groups including no-infection, lower respiratory tract infection (LRTI) and SSI. Patient characteristics was recorded. Patients were followed up until discharge. A multiple linear regression model including SSI and other factors including age, sex, comorbidity and antibiotic treatments was performed to explore the impact of SSI on increased antibiotic duration among LC patients with postoperative infection. A total of 88 patients were included, with 26 (29.5%) in no-infection group, 38 (43.2%) in LRTI group, and 24 (27.3%) in SSI group. Laryngocutaneous fistula occurred in 8 (33.3%) patients with SSI. Thirteen (34.2%) patients in LRTI group and 9 (37.5%) patients in SSI group experienced postoperative infection within 2 days after surgery, and antibiotic susceptibility tests were performed in 18 (47.4%) and 12 (50.0%) patients in LRTI and SSI group, respectively (P>0.05 for both). Levofloxacin and cefoperazone-sulbactam were the most commonly used antibiotics for postoperative infection in both LRTI and SSI groups (P>0.05 for both), irrespective of antibiotic susceptibility tests or not. The postoperative antibiotic duration in SSI group was significantly longer than that in LRTI group (13.62±4.28 days in SSI vs. 11.22±3.64 days in LRTI, P=0.021). A multiple linear regression analysis including SSI, age, sex, diabetes, antibiotic susceptibility test and hypoalbuminemia showed that, SSI was independently associated with increased antibiotic duration with LRTI as the reference among LC patients diagnosed [regression coefficient β=3.02, 95% confidence interval (CI): 1.01-5.03, P=0.004], whereas antibiotic susceptibility test was not (P=0.467). SSI may be independently associated with increased postoperative antibiotic duration in patients with LC with or without antibiotic susceptibility test.

Clinical and Microbiological Efficacy of CSE-1034 in Treatment of Acute Bacterial Infections: A Systematic Review and Meta-Analysis of Randomized Controlled Trials

This study aimed to conduct a meta-analysis to assess the clinical and microbiological efficacy of CSE-1034 for treating acute bacterial infections in adult patients. PubMed, Embase, ClinicalTrials.gov, and Cochrane databases were searched from their inception until April 2022 for relevant randomized controlled trials (RCTs). Only RCTs evaluating CSE-1034 and comparators for treating acute bacterial infections in adult patients were included. The primary outcome was the clinical response rate at the end of treatment (EOT) evaluation. Five RCTs were included. A total of 950 patients (n:638 in the UTI group, n:186 in the lower respiratory tract infection group, n:70 in the bone and joint infection group, and n:56 in SSSI) were included in this meta-analysis; 478 and 472 patients received CSE-1034 and comparators, respectively. Overall, CSE-1034 had a higher clinical cure rate at EOT than did the comparators (95.3% [384/403] vs. 81% [319/394], RR, 1.2; 95%CI, 1.04-1.39; I2=92%). Moreover, the clinical failure rate of CSE-1034 was lower than that of the comparators (RR, 0.04; 95%CI, 0.01-0.13; I2=0%). CSE-1034 also had a higher microbiological eradication rate than the comparators (92.9% [315/339] vs. 71.1% [216/304], RR, 1.53; 95%CI, 1.06-2.21; I2=97%). The clinical and microbiological efficacy of CSE-1034 is comparable or even superior in treating acute bacterial infections.

Clinical Utility of In-house Metagenomic Next-generation Sequencing for the Diagnosis of Lower Respiratory Tract Infections and Analysis of the Host Immune Response.

Only few pathogens that cause lower respiratory tract infections (LRTIs) can be identified due to limitations of traditional microbiological methods and the complexity of the oropharyngeal normal flora. Metagenomic next-generation sequencing (mNGS) has the potential to solve this problem. This prospective observational study sequentially enrolled 93 patients with LRTI and 69 patients without LRTI who visited Peking University People's Hospital in 2019. Pathogens in bronchoalveolar lavage fluid (BALF) specimens were detected using mNGS (DNA and RNA) and traditional microbiological assays. Human transcriptomes were compared between LRTI and non-LRTI, bacterial and viral LRTI, and tuberculosis and nontuberculosis groups. Among 93 patients with LRTI, 20%, 35%, and 65% of cases were detected as definite or probable pathogens by culture, all microbiological tests, and mNGS, respectively. Our in-house BALF mNGS platform had an approximately 2-working-day turnaround time and detected more viruses and fungi than the other methods. Taking the composite reference standard as a gold standard, it had a sensitivity of 66.7%, specificity of 75.4%, positive-predictive value of 78.5%, and negative-predictive value of 62.7%. LRTI-, viral LRTI-, and tuberculosis-related differentially expressed genes were respectively related to immunity responses to infection, viral transcription and response to interferon-γ pathways, and perforin 1 and T-cell receptor B variable 9. Metagenomic DNA and RNA-seq can identify a wide range of LRTI pathogens, with improved sensitivity for viruses and fungi. Our in-host platform is likely feasible in the clinic. Host transcriptome data are expected to be useful for the diagnosis of LRTIs.

Lactate dehydrogenase isoenzymes in patients with acute exacerbation of chronic obstructive pulmonary disease: An exploratory cross-sectional study

We aimed to evaluate differences in serum lactate dehydrogenase (LDH) isoenzymes between patients hospitalized for acute exacerbation of chronic obstructive pulmonary disease (AECOPD) and other lower respiratory tract infections (LRTIs). Based on self-reported COPD diagnosis, 71 participants were divided into AECOPD (n = 38, 29 males, mean age 70.5 years) and LRTI (n = 33, 12 males, mean age 70.4 years) groups. Information on demographics, comorbidities, and COPD severity markers, as well as arterial blood gases and laboratory data were collected, while serum LDH electrophoresis was performed to examine the LDH isoenzymes. Adjusting for sex, age, comorbidities, degree of hypoxemia, inflammation markers, muscle and myocardial enzymes, and total serum LDH, the mean differences (95 % confidence intervals) in the ratios of serum LDH isoenzymes to total serum LDH between groups (LDHxAECOPD − LDHxLRTI) were statistically significant for LDH1 [4.9 (1.4 to 8.3)], LDH2 [3.0 (0.1 to 5.8)], LDH3 [−4.3 (−6.3 to −2.3)], and LDH4 [−3.2 (−4.9 to −1.5)]. A sum of LDH3 and LDH4 ratios below 29 % had the highest discriminative ability to classify a subject in the AECOPD group (AUC 0.841, sensitivity 76 %, specificity 87 %). Aerobic metabolic adaptive mechanisms in respiratory muscles during AECOPD could explain the above differences.

Respiratory syncytial virus and human metapneumovirus after allogeneic hematopoietic stem cell transplantation: Impact of the immunodeficiency scoring index, viral load, and ribavirin treatment on the outcomes.

Respiratory viral infections are a major cause of morbidity and mortality among stem cell transplant recipients. While there is a substantial amount of information on prognostic factors and response to ribavirin therapy is available for RSV infections, this information is largely lacking for hMPV. In total, 71 patients were included in this study: 47 patients with RSV and 24 with hMPV. Forty-one patients presented as an upper respiratory tract infection (URTI) and 30 as a primary lower respiratory tract infection (LRTI). Patients were stratified as per ISI criteria into low-, moderate-, and high-risk groups. Twenty-two patients in the URTI cohort received treatment with ribavirin (mainly oral), and 19 patients received no antiviral therapy. The decision for antiviral treatment was at the discretion of the attending physician. All 30 patients with primary LRTI and 10 patients with secondary LRTI were treated with ribavirin, 95% with the intravenous formulation. 45% of these patients received additional treatment with intravenous immunoglobulins. The viral load was assessed indirectly by using the CT value of the RT-PCR. In the cohort, as whole 11.5% suffered a virus-associated death, 5% in the URTI group, and 20% in the LRTI group. Sixty-day mortality was significantly higher in the ISI high-risk group (log-rank P=.05). Mortality was independent of the type of virus (P=.817). Respiratory failure with an indication for mechanical ventilation developed in 11.5%, this risk was independent of the type of virus. Progression from URTI to LRTI was observed in 24% of cases with a significantly higher risk (75%) in the ISI high group (log-rank P=.001). In the ISI high-risk group, treatment with ribavirin significantly reduced the risk of progression (log-rank P<.001). Neither the type of virus nor the viral load in the nasopharyngeal swab impacted the risk of progression (P=.529 and P=.141, respectively). The detection of co-pathogens in the BAL fluid was borderline significant for mortality (P=.07). We could detect no differences between RSV and hMPV with respect to progression to LRTI, risk of respiratory failure or need for mechanical ventilation and virus-associated death. The ISI index is of predictive value in hMPV patients with a high ISI score and treatment with oral ribavirin has an equivalent protective effect in RSV and hMPV patients. Treatment of LRTI with intravenous ribavirin results in a similar outcome in RSV- and hMPV-infected patients. We could not detect any benefit of adjunctive treatment with immunoglobulins in both primary and secondary LRTI. No role of viral load as an independent prognostic marker could be detected either for progression to LRTI or death.

Association between anemia and acute lower respiratory tract infection in under-five children at Puducherry, India: a case control study

Background: Anemia has been widely studied as an important factor in the immunity composition of under five children. The incidence of infections in children can be attributed to some extend to the prevalence of anemia among them. Hence this study aimed at exploring the association between anemia and lower respiratory tract infection (LRTI) among the 6 months to 5 years old children as an effort to establish anemia as an independent risk factor for LRTI.Methods: A case-control study was conducted among 200 children in the age group of 6 months–5 years who attended the out-patient and in-patient unit of the department of paediatrics during July to September 2019. Accordingly 100 cases of LRTI and 100 normal controls were age and gender matched and their parents were interviewed using a semi-structured questionnaire. Blood investigations were done and documented in a proforma. The association between anemia and LRTI was studied statistically.Results: Anemia was associated strongly with LRTI [odds ratio=4.96 (2.72, 9.1)] with 68% of the cases with LRTI manifesting anemia. The highest level of anemia was recorded among those with LRTI in the 25-42 months age group (80.8%) which was significantly (p&lt;0.001) higher than controls. The mean hemoglobin level was 9.6±0.8 gm% among the cases which was significantly lower (p&lt;0.001) than that of the controls (11.7±1.1 gm%). The mean iron level was 40±7.3 μg/dL among cases and 72±12.1μg/dL among the non-LRTI group (p&lt;0.001).Conclusions: Anemia was significantly associated with LRTI group compared to the control group proving it to be an independent risk factor for LRTI.

Respiratory viral infections in infancy and school age respiratory outcomes and healthcare costs.

To determine the impact of viral lower respiratory tract infections (LRTIs) in infancy including rhinovirus (RV) and infancy respiratory syncytial virus (RSV), on school age pulmonary function and healthcare utilization in prematurely born children. School age respiratory outcomes would be worse and healthcare utilization greater in children who had viral LRTIs in infancy. Prospective study. A cohort of prematurely born children who had symptomatic LRTIs during infancy documented, was recalled. Pulmonary function was assessed at 5 to 7 years of age and health related costs of care from aged one to follow-up determined. Fifty-one children, median gestational age 33+6 weeks, were assessed at a median (IQR) age 7.03 (6.37-7.26) years. Twenty-one children had no LRTI, 14 RV LRTI, 10 RSV LRTI, and 6 another viral LRTI (other LRTI). Compared to the no LRTI group, the RV group had a lower FEV1 (P = 0.033) and the other LRTI group a lower FVC (P = 0.006). Non-respiratory medication costs were higher in the RV (P = 0.018) and RSV (P = 0.013) groups. Overall respiratory healthcare costs in the RV (£153/year) and RSV (£27/year) groups did not differ significantly from the no LRTI group (£56/year); the other LRTI group (£431/year) had higher respiratory healthcare costs (P = 0.042). In moderately prematurely born children, RV and RSV LRTIs in infancy were not associated with higher respiratory healthcare costs after infancy. Children who experienced LRTIs caused by other respiratory viruses (including RV) had higher respiratory healthcare costs and greater pulmonary function impairment.

RSV infection in Istanbul: risk factors and frequency

Respiratory syncytial virus (RSV) is one of the most common causes of acute respiratory infections in all age groups especially under two years. The aim of this study was to investigate the frequency and clinical features of RSV in hospitalized children under two years of age with the diagnosis of lower respiratory tract infections (LRTI) in our region. Between September 2011- May 2013, hospitalized children aged 0-2 years with the diagnosis of viral LRTI, in which nasopharengeal secretions were tested for the presence of the RSV antigen, were included in this prospective study. Among the total of 361 hospitalized children who were investigated for RSV antigen, 138 (38%) were female and 223 (62%) were male. The mean age of the group was 5,7±5,1 months (0-24 months). RSV antigen in nasopharyngeal secretions was positive in 68 (19%) of 361 patients. RSV infection was detected significantly higher in December and January (p = 0.003). RSV positivity was significantly higher in patients aged under 6 months (p=0.01), with shorter duration of breastfeeding (p = 0.02), low socioeconomic status (p = 0.02), and also born with spontaneous vaginal delivery (p = 0.007). In RSV(+) LRTI group, children were associated with severe disease than RSV (- LRTI group (p = 0.014). Since there is lack of data investigating the frequency and the risk factors of RSV respiratory infections in our region, the present study is important for providing new data. Furthermore, this is the second study investigating the correlation between RSV positivity and meteorological conditions in Turkey.

Chronic respiratory morbidity following viral lower respiratory tract infections in prematurely born infants

Human meta-pneumovirus (hMPV) and rhinovirus (RV) lower respiratory tract infections (LRTIs) may result in acute symptoms similar to those of respiratory syncytial virus (RSV) LRTI. We, therefore, tested the hypothesis that other viral LRTI, as RSV LRTI, will increase healthcare utilization and chronic respiratory morbidity in prematurely born infants. One hundred and twelve prematurely born infants were followed prospectively. Hospital admissions and general practitioner (GP) attendances were recorded and cough and wheeze documented by diary card. Nasopharyngeal aspirates (NPA) were obtained for every LRTI and analyzed to identify RSV (A and B), hMPV, RV, parainfluenza (1 and 2) and influenza (A and B) viruses. Eighty-four infants suffered 126 LRTIs; 94 viruses (41 RSV, 36 RV, seven hMPV, five parainfluenza (1, 2 or 3) and five influenza (A or B) viruses) were identified from 82 of the 126 NPAs. Compared to the no viral LRTI group, infants with only RSV infection had more (P =0 .038) and longer (P =0 .045) hospital admissions, more GP attendances (P =0 .024), more cough (P =0 .030) and wheeze at follow up (P =0 .018). If infants with dual infections are also considered, however, infants with a hMPV LRTI, with or without other viral RNA being detected, compared to the no viral group, had more hospital admissions (P =0 .005), longer admissions ( P< 0.001), more GP visits (P =0 .029), more days of cough (P =0 .008) and more days of wheeze (P =0 .004). RSV and possibly hMPV, but not RV, LRTI increase healthcare utilization and respiratory morbidity in prematurely born infants.

Viral lower respiratory tract infections and preterm infants' healthcare utilisation.

The aim of this study was to determine whether respiratory syncytial virus (RSV) and other viral lower respiratory tract infections (LRTI) in prematurely born infants were associated with similar effects on healthcare utilisation and related cost of care in the second compared to the first year after birth. Thirteen infants who had RSV LRTIs (RSV), 21 who had other viral LRTIs (other viral) and 25 had no viral LRTIs (no LRTI) were prospectively followed. Nasopharyngeal aspirates were collected whenever an infant had an LRTI regardless of whether it was in the hospital or in the community. Healthcare utilisation and the health-related cost of care were determined. Only the RSV group compared to the no LRTI group had higher overall respiratory costs in both year 1 (mean, £3,917 versus £24; p < 0.041) and year 2 (mean, £1,164 versus £61; p = 0.012). Only the RSV group required respiratory admissions; the RSV admission rate in year 2 was 3.4 % (number needed to treat 59). RSV LRTIs are associated with increased healthcare utilisation and cost of care in the first and second year; nevertheless, if prophylaxis is to be cost-effective in the second year, a high risk group needs to be identified.

Lung function of preterm infants before and after viral infections.

Our aim was to determine whether viral lower respiratory tract infections (LRTIs) adversely affect prematurely born infants' lung function at follow up. Seventy infants, median gestational age 34 (range, 24-35) weeks were prospectively followed; 32 had an RSV (n = 14) or another respiratory viral (n = 18) LRTI (viral LRTI group) and 38 had no LRTI (no LRTI group). Six of the viral LRTI and five of the no LRTI group had been hospitalised. Nasopharyngeal aspirates (NPAs) obtained whenever the infants had an LRTI. Lung function (functional residual capacity [FRCHe], compliance [Crs] and resistance [Rrs] of the respiratory system) was measured at 36weeks postmenstrual age (PMA) and 1year corrected. At 1year, lung volume (FRCpleth) and airways resistance (Raw) were also assessed. There were no significant differences in the lung function of the two groups at 36weeks PMA but at 1year, the viral LRTI compared to the no LRTI group had a higher mean Raw (23 versus 17cm H2O/l/s, p = 0.0068), the differences remained significant after adjustment. These results suggest viral LRTIs, regardless of whether hospitalisation is required, adversely affect prematurely born infants' airway resistance at follow up.

Respiratory outcome of prematurely born infants following human rhinovirus A and C infections

Human rhinoviruses (HRVs) are a common cause of lower respiratory tract infections (LRTIs) and are associated with chronic respiratory morbidity. Our aim was to determine whether HRV species A or C were associated with chronic respiratory morbidity and increased health care utilisation in prematurely born infants. A number of 153 infants with a median gestational age of 34 (range 23-35) weeks were prospectively followed. Nasopharyngeal aspirates were collected whenever the infants had LRTIs regardless of hospitalisation status. Parents completed a respiratory diary card and health questionnaire about their infant when they were 11 and 12 months corrected age, respectively. The health-related cost of care during infancy was calculated from the medical records using the National Health Service (NHS) reference costing scheme and the British National Formulary for children. There were 32 infants that developed 40 HRV LRTIs; samples were available from 23 of the 32 infants for subtyping. Nine infants had HRV-A LRTIs, 13 HRV-C LRTIs, and one infant had a HRV-B LRTI. Exclusion of infants who also had RSV LRTIs revealed that the infants who had a HRV-C LRTI were more likely to wheeze (p < 0.0005) and use respiratory medications (p < 0.0005) and had more days of wheeze (p = 0.01) and used an inhaler (p = 0.02) than the no LRTI group. In addition, the respiratory cost of care was greater for the HRV-C LRTI than the no LRTI group (p < 0.0005). Our results suggest HRV-C is associated with chronic respiratory morbidity during infancy in prematurely born infants.

Rhinovirus infection and healthcare utilisation in prematurely born infants

Our aim was to determine whether rhinovirus (RV) lower respiratory tract infections (LRTIs) in prematurely born infants increase health-related cost of care during infancy. 153 infants born at <36 weeks of gestation were prospectively followed to 1 year. Cost of care was calculated from the National Health Service reference costing scheme and healthcare utilisation determined by examining hospital/general practitioner records. 20 infants developed RV LRTIs (RV group), 17 respiratory syncytial virus (RSV) LRTIs (RSV group), 12 both RV and RSV LRTIs (RV/RSV group) and 74 had no LRTI (no LRTI group). Compared with the no LRTI group, the RV/RSV LRTI group had the greatest increase in adjusted mean cost (difference GBP 5769), followed by the RV LRTI group (difference GBP 278) and, finally, the RSV LRTI group (difference GBP 172) (p=0.045). The RV group had more outpatient (p<0.05) and respiratory-related general practitioner (p<0.05) attendances, more wheezed at follow-up (p<0.001) than the no LRTI group and more had respiratory-related outpatient attendances than the RSV LRTI group (p<0.05). We conclude that RV LRTIs were associated with increased health-related cost of care during infancy; our results suggest that the RV group compared with the RSV group suffered greater chronic respiratory morbidity.

O.5.1 Prevalence of human bocavirus and KI/WU polyomaviruses in children with and without lower respiratory tract infection at the pediatric intensive care unit

Purpose: Little is known about the prevalence of human bocavirus (HBoV), KI polyomavirus (KIPyV) and WU polyomavirus (WUPyV) in children with severe lower respiratory tract infections (LRTIs) admitted to the pediatric intensive care unit (PICU). The aim of our study was to evaluate the prevalence of HBoV, KIPyV and WUPyV in PICU patients with and without LRTI. Methods: For the LRTI group PICU patients under five years of age were included during three winters (2005–2008). For the control group PICU patients under 18 years of age admitted for other reasons than LRTI were included during one winter (2005–2006). Respiratory specimens of both groups were tested for HBoV, KIPyV and WUPyV by real-time PCR. Specimens in the LRTI group were also tested by real-time PCR for other respiratory viruses. Results: Respiratory specimens of 78 LRTI patients and 83 controls were examined. HBoV, KIPyV and WUPyV were detected in 4 (5.1%), 0 (0%), and 2 (2.6%) LRTI patients and 4 (4.8%), 4 (4.8%), and 2 (2.4%) controls, respectively. Multiple viruses were present in 3 out of 4 HBoV and 2 out of 2 WUPyV positive LRTI patients. In the LRTI patient with single HBoV infection, the virus was present in very high quantities. Conclusion: In conclusion, at the PICU-population level detection of HBoV, KIPyV, and WUPyV viruses was not associated with lower respiratory tract infection in children admitted to the PICU. In individual patients, however, HBoV may cause LRTI.

O.5.2 Correlation between (semi-)quantity of respiratory viruses using a multiple RT-PCR and clinical respiratory symptoms in children under 6 years

Purpose: Little is known about the prevalence of human bocavirus (HBoV), KI polyomavirus (KIPyV) and WU polyomavirus (WUPyV) in children with severe lower respiratory tract infections (LRTIs) admitted to the pediatric intensive care unit (PICU). The aim of our study was to evaluate the prevalence of HBoV, KIPyV and WUPyV in PICU patients with and without LRTI. Methods: For the LRTI group PICU patients under five years of age were included during three winters (2005–2008). For the control group PICU patients under 18 years of age admitted for other reasons than LRTI were included during one winter (2005–2006). Respiratory specimens of both groups were tested for HBoV, KIPyV and WUPyV by real-time PCR. Specimens in the LRTI group were also tested by real-time PCR for other respiratory viruses. Results: Respiratory specimens of 78 LRTI patients and 83 controls were examined. HBoV, KIPyV and WUPyV were detected in 4 (5.1%), 0 (0%), and 2 (2.6%) LRTI patients and 4 (4.8%), 4 (4.8%), and 2 (2.4%) controls, respectively. Multiple viruses were present in 3 out of 4 HBoV and 2 out of 2 WUPyV positive LRTI patients. In the LRTI patient with single HBoV infection, the virus was present in very high quantities. Conclusion: In conclusion, at the PICU-population level detection of HBoV, KIPyV, and WUPyV viruses was not associated with lower respiratory tract infection in children admitted to the PICU. In individual patients, however, HBoV may cause LRTI.

Mycoplasma pneumoniae infection in a pediatric population: Analysis of soluble immune markers as risk factors for asthma

Epidemiologic and clinical evidence suggests that respiratory tract infection with Mycoplasma pneumoniae maybe implicated in the initiation and exacerbation of asthma. This study examines the incidence and frequency of M. pneumoniae infection in children and evaluates the serum cytokine profile and total immunoglobulin E (IgE) levels in a subgroup of patients with clinical presentation of either upper respiratory tract infections (URTI) or lower respiratory tract infections (LRTI). A total of 6986 serum samples were tested for specific IgM anti– M. pneumoniae, and a 4-year cyclical incidence of M. pneumoniae infection was confirmed; however; the peak age of highest incidence in the most recent epidemic fell to 3–4 years. A high incidence was also observed in the 6–7-year age group. Children presenting with LRTI, when compared with those patients presenting with URTI, had significantly higher serum levels of the proinflammatory cytokines, interleukin (IL)–1α, IL-6, the T-helper (Th)2-type cytokines, and IL-4 and IL-10. The Th1-type cytokines, IL-2 and IL-12, were within the normal range, whereas interferon-γ levels were slightly raised. Total serum immunoglobulin E levels were significantly higher in the LRTI group ( p < 0.02). Our findings support the emerging evidence that respiratory tract infection with Mycoplasma pneumoniae results in an increased proinflammatory and Th2-type cytokine response that may precede the initiation and exacerbation of asthma.