Hospital-Acquired Pneumonia/Ventilator-Associated Pneumonia and Ventilator-Associated Tracheobronchitis in COVID-19.

Although few studies evaluated the incidence of hospital-acquired pneumonia (HAP) or ventilator-associated tracheobronchitis in COVID-19 patients, several studies evaluated the incidence of ventilator-associated pneumonia (VAP) in these patients. Based on the results of a large multicenter European study, VAP incidence is higher in patients with SARS-CoV-2 pneumonia (36.1%), as compared with those with influenza pneumonia (22.2%), or no viral infection at intensive care unit (ICU) admission (16.5%). Potential explanation for the high incidence of VAP in COVID-19 patients includes long duration of invasive mechanical ventilation, high incidence of acute respiratory distress syndrome, and immune-suppressive treatment. Specific risk factors for VAP, including SARS-CoV-2-related pulmonary lesions, and bacteria-virus interaction in lung microbiota might also play a role in VAP pathogenesis. VAP is associated with increased mortality, duration of mechanical ventilation, and ICU length of stay in COVID-19 patients. Further studies should focus on the incidence of HAP especially in ICU non-ventilated patients, better determine the pathophysiology of these infections, and evaluate the accuracy of currently available treatment guidelines in COVID-19 patients.

Impact of social distancing in response to COVID-19 on hospitalizations for laryngitis, tracheitis, otitis media, and mastoiditis in children aged 0 to 9 years in Brazil.

OBJECTIVE: The objective of this study is to evaluate the impact of social distancing resulting from COVID-19 in hospitalizations for infections of the upper airways (URTI), such as acute laryngitis, tracheitis, and otitis media in children aged 0 to 9 years in Brazil, considering that they share the same forms of transmission. METHODS: Data on hospitalizations for acute airway changes and their complications in children <9 years old were obtained from the Database of the Brazilian Department of Public Health Informatics for the period 2015 to 2020. These data were also analyzed by macroregions of Brazil (North, Northeast, Southeast, South, and Midwest). The effect of the social distancing strategy on the increase of acute laryngitis, tracheitis, otitis media, and mastitis, as absolute and relative reductions, was calculated by analyzing the annual calculation of 2015-2019 vs 2020. RESULTS: All the hospitalizations compared in the Unified Health System (SUS) for laryngitis and acute tracheitis and otitis media decreased, considering all states of Brazil. The largest reduction in hospitalization reduction was in the North, with -94% in 2015-2019 vs 2020 in cases of laryngitis and acute tracheitis, and in the Midwest, with - 85% in 2015-2019 vs 2020 in cases of otitis media. CONCLUSION: Hospitalizations for laryngitis, acute tracheitis, and acute otitis media in children <9 years old decreased between March and July 2020 in Brazil, when social distancing measures were adopted due to the COVID-19 pandemic.

Demographic Characteristics of Children Diagnosed with Bacterial Tracheitis.

OBJECTIVES: Examine the presentation and clinical course of patients with bacterial tracheitis (BT). Identify if socioeconomic differences exist among children who present with BT. METHODS: This was a retrospective case series from a tertiary care pediatric medical center. The study group included patients less than 18 years old who were diagnosed with BT from January 2011 to March 2019. Patients with a tracheostomy and those who developed BT after prolonged hospitalization were excluded. Patient demographics were compared with the demographics of the counties surrounding the hospital. RESULTS: 33 patients with BT met inclusion criteria. The most common presenting symptoms were difficulty breathing, stridor, and sore throat (81.8% each), followed by cough (78.8%). Median length of stay was 3 days [interquartile range (IQR):2-4]. 19 patients (57.5%) were admitted to the intensive care unit. Intubation was required for 13 patients (39.4%), for a median length of 2 days [IQR:2-2]. Methicillin sensitive staphylococcus aureus was the most common bacterial etiology (33%). Mean presenting age was 8.58 years [95% confidence interval:7.3-9.9] and 14 patients were female (42.4%). 31 patients were white (93.9%), 1 was black (3%), and 1 was Hispanic (3%). BT patients were more likely to have private insurance compared to comparison (81.8% vs 63.4%, P < .001). CONCLUSION: Children who presented with BT were more likely to be privately insured than a comparison population.

Traqueobronquitis necrosante con obstrucción del tubo endotraqueal en pacientes COVID-19 / Necrotizing tracheobronchitis with endotracheal tube obstruction in COVID-19 patients

No disponible

Seroprevalence of infectious laryngotracheitis disease in backyard chickens in villages of Ada'a district, Oromia, Ethiopia: first report.

As per the report from the OIE in 2005, infectious laryngotracheitis (ILT) has not been yet reported in Ethiopia. Hence, considering the evident clinical signs on-field associated with the disease, it felt that there is a need to identify the disease and to protect the chicken population. The study was, therefore, aimed at identifying the seroprevalence of ILT virus from the samples collected from chickens in backyard system, so as to notify its prevalence and setup recommendations for further research in the future. Consequently, cross-sectional study was conducted in eleven purposefully selected peasant associations (PA) of Ada'a district from January to May 2019 to determine ILT in backyard chickens. A total number of 426 sera sample of backyard chickens were randomly collected from 11 PA and each sera was exposed to an indirect enzyme-linked immunosorbent assay (iELISA), at the National Animal Health Diagnostic and Investigation Center, Ethiopia. Out of 426 samples, 233 (54.7%) samples were found positive for ILT virus-specific antibody. The highest prevalence was recorded in Wajitu (83.3%), whereas the least was in Giche (40.7%) PA. There was a statistically significant difference (p < 0.05) among seroprevalence and study PA. The result of this study revealed that a high prevalence of ILT virus is circulating among backyard chickens in the selected PA of Ada'a district, which could significantly affect the poultry sector. Thus, further studies on the circulating strains and the epidemiology of the disease should be carried using a molecular diagnostic test.

Acute pediatric tracheitis: Distinguishing the disease by tracheostomy status.

OBJECTIVES: Tracheitis is an upper airway infection that often presents in patients with tracheostomies and can potentially cause airway obstruction. This study aims to use a nationwide database to identify a large cohort of pediatric patients admitted with tracheitis to elucidate the management and resource utilization associated with the disease both with and without tracheostomies. METHODS: The Kids' Inpatient Database (KID) 2012 was used to identify 2394 weighted discharges with acute tracheitis, with or without obstruction, as the primary diagnosis. Data on prior tracheostomy status, demographics, hospital characteristics, management, and resource utilization were obtained. Two groups of interest, based on presence of prior tracheostomy, were studied. Linear regression was performed to determine independent predictors of total charges. RESULTS: The mean age was 5.52 years (SD: 5.54), mean length of stay (LOS) was 6.37 days (SD: 10.18), and mean total charges were $60,996.61 (SD: 107,798.41). Patients with prior tracheostomy had lower rates of endoscopy and endotracheal intubation than patients without (p < 0.0005). There was no significant difference in LOS (p = 0.076) or total charges (p = 0.210) between the groups based on prior tracheostomy status. CONCLUSION: Pediatric tracheitis should be differentiated on the basis of tracheostomy status. We propose that tracheitis diagnosis codes should be distinguished by the presence of tracheostomy as "open" and the absence of tracheostomy as "closed."

Traqueobronquite associada à ventilação mecânica: uma atualização / Ventilator-associated tracheobronchitis: an update

RESUMO As infecções do trato respiratório inferior associadas à ventilação mecânica são uma das complicações mais frequentes em pacientes em ventilação mecânica. Há muitos anos, a traqueobronquite associada à ventilação mecânica tem sido considerada uma doença que não demanda antibioticoterapia. Na última década, diversos estudos demonstraram que a traqueobronquite associada à ventilação mecânica deve ser considerada um processo intermediário que leva à pneumonia associada à ventilação mecânica, uma vez que apesar de ter impacto limitado sobre a mortalidade dos pacientes gravemente enfermos internados nas unidades de terapia intensiva, em contrapartida, demonstra associação significativa com o aumento dos custos hospitalares desses pacientes, assim como do tempo de internação na unidade de terapia intensiva e hospitalar, do uso de antibióticos, e da duração da ventilação mecânica. Embora ainda necessitemos de evidências científicas mais robustas, especialmente no que tange às modalidades terapêuticas, os dados atuais a respeito da traqueobronquite associada à ventilação mecânica salientam que há desfechos suficientemente importantes que exigem vigilância epidemiológica e controle clínico adequados.

ABSTRACT Ventilator-associated lower respiratory tract infection is one of the most frequent complications in mechanically ventilated patients. Ventilator-associated tracheobronchitis has been considered a disease that does not warrant antibiotic treatment by the medical community for many years. In the last decade, several studies have shown that tracheobronchitis could be considered an intermediate process that leads to ventilator-associated pneumonia. Furthermore, ventilator-associated tracheobronchitis has a limited impact on overall mortality but shows a significant association with increased patient costs, length of stay, antibiotic use, and duration of mechanical ventilation. Although we still need clear evidence, especially concerning treatment modalities, the present study on ventilator-associated tracheobronchitis highlights that there are important impacts of including this condition in clinical management and epidemiological and infection surveillance.

Effects of personal nitrogen dioxide exposure on airway inflammation and lung function.

BACKGROUND: Few epidemiological studies have evaluated the respiratory effects of personal exposure to nitrogen dioxide (NO2), a major traffic-related air pollutant. The biological pathway for these effects remains unknown. OBJECTIVES: To evaluate the short-term effects of personal NO2 exposure on lung function, fractional exhaled nitric oxide (FeNO) and DNA methylation of genes involved. METHODS: We conducted a longitudinal panel study among 40 college students with four repeated measurements in Shanghai from May to October in 2016. We measured DNA methylation of the key encoding genes of inducible nitric oxide synthase (NOS2A) and arginase (ARG2). We applied linear mixed-effect models to assess the effects of NO2 on respiratory outcomes. RESULTS: Personal exposure to NO2 was 27.39 ±â€¯23.20 ppb on average. In response to a 10-ppb increase in NO2 exposure, NOS2A methylation (%5 mC) decreased 0.19 at lag 0 d, ARG2 methylation (%5 mC) increased 0.21 and FeNO levels increased 2.82% at lag 1 d; and at lag 2 d the percentage of forced vital capacity, forced expiratory volume in 1 s and peak expiratory flow in predicted values decreased 0.12, 0.37 and 0.67, respectively. The model performance was better compared with those estimated using fixed-site measurements. These effects were robust to the adjustment for co-pollutants and weather conditions. CONCLUSIONS: Our study suggests that short-term personal exposure to NO2 is associated with NOS2A hypomethylation, ARG2 hypermethylation, respiratory inflammation and lung function impairment. The use of personal measurements may better predict the respiratory effects of NO2.

Ventilator-associated tracheobronchitis: an update. / Traqueobronquite associada à ventilação mecânica: uma atualização.

Ventilator-associated lower respiratory tract infection is one of the most frequent complications in mechanically ventilated patients. Ventilator-associated tracheobronchitis has been considered a disease that does not warrant antibiotic treatment by the medical community for many years. In the last decade, several studies have shown that tracheobronchitis could be considered an intermediate process that leads to ventilator-associated pneumonia. Furthermore, ventilator-associated tracheobronchitis has a limited impact on overall mortality but shows a significant association with increased patient costs, length of stay, antibiotic use, and duration of mechanical ventilation. Although we still need clear evidence, especially concerning treatment modalities, the present study on ventilator-associated tracheobronchitis highlights that there are important impacts of including this condition in clinical management and epidemiological and infection surveillance.

As infecções do trato respiratório inferior associadas à ventilação mecânica são uma das complicações mais frequentes em pacientes em ventilação mecânica. Há muitos anos, a traqueobronquite associada à ventilação mecânica tem sido considerada uma doença que não demanda antibioticoterapia. Na última década, diversos estudos demonstraram que a traqueobronquite associada à ventilação mecânica deve ser considerada um processo intermediário que leva à pneumonia associada à ventilação mecânica, uma vez que apesar de ter impacto limitado sobre a mortalidade dos pacientes gravemente enfermos internados nas unidades de terapia intensiva, em contrapartida, demonstra associação significativa com o aumento dos custos hospitalares desses pacientes, assim como do tempo de internação na unidade de terapia intensiva e hospitalar, do uso de antibióticos, e da duração da ventilação mecânica. Embora ainda necessitemos de evidências científicas mais robustas, especialmente no que tange às modalidades terapêuticas, os dados atuais a respeito da traqueobronquite associada à ventilação mecânica salientam que há desfechos suficientemente importantes que exigem vigilância epidemiológica e controle clínico adequados.

[Maternal occupational hazards during pregnancy and allergy in the first year of life as risk factors of laryngotracheitis recurrence in сhildren].

OBJECTIVE: Introduction: Some studies have found associations between maternal occupational hazards during pregnancy and allergy in children. The role of allergy and maternal occupational hazards in predisposition to laryngotracheitis (LT) needs to be clarified. The aim: Objective of the research was to evaluate the possibility of relationship between maternal occupational hazards during pregnancy and allergy in the first year of life in children with LT and recurrent laryngotracheitis (RLT), as well as the debut timing of LT and RLT depending on allergy. PATIENTS AND METHODS: Materials and methods: A questionnaire was used to obtain life history of 405 children aged 6-14 years: 133 children with LT (1-3 episodes of LT), 74 children with RLT (4 or more episodes of LT) and 198 age matched children of control group. RESULTS: Results: The percentage of children with allergy in case of RLT was 48,6% and exceeded the percentage of children with allergy in case of LT and control group in 1,7 and 2,1 times, correspondingly (p<0,01). The tendency (p=0,06) towards increase of the percentage of children with allergy among children with RLT in case of maternal occupational health hazards has been revealed. Among children with RLT percentage of those who had allergy and the debut timing in the first year of life exceeded 3 times the corresponding percentage in children with LT (p<0,01). There was no difference in the debut timing of LT and RLT between children with and without allergу. CONCLUSION: Conclusions: Maternal occupational health hazards during pregnancy and allergy in the first year of life may be considered as risk factors of RLT in children.

Postoperative outcomes of frequent exacerbator patients with Chronic Obstructive Pulmonary Disease after resection of Non-Small Cells Lung Cancer.

Chronic obstructive pulmonary disease (COPD) is a risk factor of post-operative complications after lung cancer resection. The influence of the "frequent exacerbator (FE)" phenotype (at least three exacerbations per year) is unknown. Postoperative outcomes of frequent exacerbators (POFE) was a prospective observational study of patients with COPD undergoing lung resection for cancer. The inclusion criteria were: age >40 years, FEV1/FVC <70%, non-urgent surgery for lung cancer, filled out self-questionnaires. The primary outcome was assessment of postoperative pulmonary complications (purulent tracheobronchitis, atelectasis, pneumonia, acute respiratory failure, need of mechanical ventilation). Secondary outcomes encompassed the prevalence of the FE phenotype and its impact on postoperative complications. A total of 682 patients were screened from June 2014 to October 2015. 93 patients with COPD were included, 21 (23%) were FE. Postoperative tracheobronchitis, atelectasis pneumonia or respiratory failure (isolated or associated) occurred in 47%, 48%, 26%, and 38% of patients, respectively. Non-invasive and invasive mechanical ventilation were necessary in 4 (4%) and 22 (23%) patients. Purulent tracheobronchitis, pneumonia and hypercapnia (this last requiring noninvasive mechanical ventilation) were more frequent in FE (p = 0.043, 0.042, 0.015); however the number of patients wth at least one respiratory complication was not different (76% vs. 52%, p = 0.056). In all patients, multivariate logistic regression identified two independent factors of postoperative respiratory complications: male sex (OR 10.6 [95% CI 1.97-57.6], p = 0.006) and the FE phenotype (OR 6.33 [1.04-38.39], p = 0.045). Occurrence of postoperative complications in patients with COPD is high. FE phenotype is an independent risk factor.

Occlusive mycotic tracheobronchitis and systemic Alphaherpesvirus coinfection in a free-living striped dolphin Stenella coeruleoalba in Italy.

A juvenile female striped dolphin Stenella coeruleoalba live stranded on 4 March 2016 at Alassio, western Ligurian Sea coast, Italy. The dolphin died shortly after stranding, and a complete postmortem examination was performed. Necropsy revealed severe tracheal occlusion and unilateral bronchial stenosis with luminal accumulation of abundant green-yellow mucous-gelatinous material. Histological features suggestive of tracheobronchial aspergillosis were observed. Cultures of lung tissue and tracheo-bronchial exudate isolated Aspergillus fumigatus, identified by a Microseq D2 LSUrDNA fungal sequencing kit. A pan-Herpesvirus nested-PCR assay on frozen samples obtained from multiple organs was positive. Phylogenetic analysis on the partial DNA polymerase gene revealed that the striped dolphin isolate was closely related to known cetacean Alphaherpesvirus sequences from the same host species. Attempted virus isolation was unsuccessful. The tissue levels of different persistent organic pollutants and the toxicological stress, evaluated using a theoretical model, showed a severely impaired immune response. This study reports the first case of occlusive mycotic tracheobronchitis in a free-living cetacean and the first molecular identification of an Alphaherpesvirus in a free-ranging striped dolphin stranded on the coast of Italy.

Update on childhood and adult infectious tracheitis.

The trachea is a pivotal organ of the respiratory tract. Rather than a genuine anatomic border, it acts as a crossroad in all respiratory infectious processes. Even though not strictly limited to the trachea, infections such as laryngotracheitis and tracheobronchitis are frequently diagnosed in children, in particular during the winter season. Infectious tracheitis etiologies are diverse and the distinction between viral and bacterial origins, albeit difficult, remains relevant considering the substantial differences in terms of gravity and therapeutic management. This literature review summarizes the microbiological and clinical aspects of community-acquired and nosocomial tracheitis in adults and children, as well as the adequate diagnostic and therapeutic approaches. It also highlights the emergence of fungal tracheitis in immunocompromised patients, of ventilator-associated tracheitis in intensive care medicine, and beyond all that the potential short and long-term consequences of tracheitis.

Pseudomonas aeruginosa and post-tracheotomy bacterial respiratory tract infection readmissions.

OBJECTIVE: Identify risk factors for readmission due to a bacterial tracheostomy-associated respiratory tract infection (bTARTI) within 12 months of discharge after tracheotomy. DESIGN/METHODS: We performed a retrospective cohort study of 240 children who underwent tracheotomy and were discharged with tracheotsomy in place between January 1, 2005 and June 30, 2013. Children with prolonged total or post-tracheotomy length of stay (LOS), less than 12 months of follow-up, or who died during the index hospitalization were excluded. Readmission for a bTARTI (eg, pneumonia, tracheitis) treated with antibiotics, as ascertained by manual chart review, was the outcome variable. We used multivariate logistic regression to identify the independent association between risk factors and hospital readmission for bTARTI within 12 months. RESULTS: At index hospitalizations for tracheotomy, the median admission age was 5 months (interquartile range [IQR] 2-43 months) and median LOS was 73 days (IQR 43-121 days). Most patients were of Hispanic ethnicity (n = 162, 68%) and were publicly insured (n = 213, 89%). Nearly half (n = 112, 47%) were discharged on positive pressure mechanical ventilation. Many (n = 103, 43%) were admitted for bTARTI within 12 months of discharge. Only Hispanic ethnicity (adjusted odds ratio [AOR] 2.0; 95% confidence interval [CI]: 1.1-3.9; P = 0.03) and acquisition of Pseudomonas aeruginosa between tracheotomy and discharge from index hospitalization (AOR 3.2; 95%CI: 1.2-8.3; P = 0.02) were independently associated with increased odds of bTARTI readmission, while discharge on gastrointestinal pro-motility agents was associated with decreased risk (AOR = 0.4; 95%CI: 0.2-0.8; P = 0.01). CONCLUSIONS: Hispanic ethnicity and post-tracheotomy acquisition of P. aeruginosa during initial hospitalization are associated with bTARTI readmission.

Incidence and prognosis of ventilator-associated tracheobronchitis (TAVeM): a multicentre, prospective, observational study.

BACKGROUND: Ventilator-associated tracheobronchitis has been suggested as an intermediate process between tracheobronchial colonisation and ventilator-associated pneumonia in patients receiving mechanical ventilation. We aimed to establish the incidence and effect of ventilator-associated tracheobronchitis in a large, international patient cohort. METHODS: We did a multicentre, prospective, observational study in 114 intensive care units (ICU) in Spain, France, Portugal, Brazil, Argentina, Ecuador, Bolivia, and Colombia over a preplanned time of 10 months. All patients older than 18 years admitted to an ICU who received invasive mechanical ventilation for more than 48 h were eligible. We prospectively obtained data for incidence of ventilator-associated lower respiratory tract infections, defined as ventilator-associated tracheobronchitis or ventilator-associated pneumonia. We grouped patients according to the presence or absence of such infections, and obtained data for the effect of appropriate antibiotics on progression of tracheobronchitis to pneumonia. Patients were followed up until death or discharge from hospital. To account for centre effects with a binary outcome, we fitted a generalised estimating equation model with a logit link, exchangeable correlation structure, and non-robust standard errors. This trial is registered with ClinicalTrials.gov, number NCT01791530. FINDINGS: Between Sept 1, 2013, and July 31, 2014, we obtained data for 2960 eligible patients, of whom 689 (23%) developed ventilator-associated lower respiratory tract infections. The incidence of ventilator-associated tracheobronchitis and that of ventilator-associated pneumonia at baseline were similar (320 [11%; 10·2 of 1000 mechanically ventilated days] vs 369 [12%; 8·8 of 1000 mechanically ventilated days], p=0·48). Of the 320 patients with tracheobronchitis, 250 received appropriate antibiotic treatment and 70 received inappropriate antibiotics. 39 patients with tracheobronchitis progressed to pneumonia; however, the use of appropriate antibiotic therapy for tracheobronchitis was associated with significantly lower progression to pneumonia than was inappropriate treatment (19 [8%] of 250 vs 20 [29%] of 70, p<0·0001; crude odds ratio 0·21 [95% CI 0·11-0·41]). Significantly more patients with ventilator-associated pneumonia died (146 [40%] of 369) than those with tracheobronchitis (93 [29%] of 320) or absence of ventilator-associated lower respiratory tract infections (673 [30%] of 2271, p<0·0001). Median time to discharge from the ICU for survivors was significantly longer in the tracheobronchitis (21 days [IQR 15-34]) and pneumonia (22 [13-36]) groups than in the group with no ventilator-associated lower respiratory tract infections (12 [8-20]; hazard ratio 1·65 [95% CI 1·38-1·97], p<0·0001). INTERPRETATION: This large database study emphasises that ventilator-associated tracheobronchitis is a major health problem worldwide, associated with high resources consumption in all countries. Our findings also show improved outcomes with use of appropriate antibiotic treatment for both ventilator-associated tracheobronchitis and ventilator-associated pneumonia, underlining the importance of treating both infections, since inappropriate treatment of tracheobronchitis was associated with a higher risk of progression to pneumonia. FUNDING: None.

Phaeohyphomycosis resulting in obstructive tracheitis in three green sea turtles Chelonia mydas stranded along the Florida coast.

Three wild immature green sea turtles Chelonia mydas were found alive but lethargic on the shores of the Indian River Lagoon and Gulf of Mexico in Florida, USA, and subsequently died. Necropsy findings in all 3 turtles included partial occlusion of the trachea by a mass comprised of granulomatous inflammation. Pigmented fungal hyphae were observed within the lesion by histology and were characterized by culture and sequencing of the internal transcribed spacer 2 domain of the rRNA gene and D1/D2 region of the fungal 28s gene. The dematiaceous fungus species Veronaea botryosa was isolated from the tracheal mass in 2 cases, and genetic sequence of V. botryosa was detected by polymerase chain reaction in all 3 cases. Genetic sequencing and fungal cultures also detected other dematiaceous fungi, including a Cladosporium sp., an Ochroconis sp., and a Cochliobolus sp. These cases are the first report of phaeohyphomycosis caused by V. botryosa in wild marine animals.

[CYCLIC VARIATIONS OF LARYNGOTRACHEITIS IN CHILDREN].

It was analyzed the incidences of laryngotracheitis (LT) in children aged 0 to 14 years in Vinnytsya between 1995 and 2008. It was studied seasonal and circadian rhythms of LT in children. The seasonal variations of LT are characterized by two-wave curve with peaks in October and March, and with a significant decrease in July and August. The incidences of LT in October and March exceed the incidences of LT in July and August in 2.6 times. Circadian variation of LT is characterized by peak at night. The incidences of LT at night exceed the incidences in the morning in 2.6 times. The total number of the incidences of LT in the evening and at night exceed the total number of the incidences of LT in the morning and in the afternoon in 1.7 times. The maximum of incidences of LT to minimum of incidences of LT per hour ratio is 5:1 in girls compared to 4:1 in boys.

Impact of air pollution on respiratory diseases in children with recurrent wheezing or asthma.

BACKGROUND: Air pollution has many negative health effects on the general population, especially children, subjects with underlying chronic disease and the elderly. The aims of this study were to evaluate the effects of traffic-related pollution on the exacerbation of asthma and development of respiratory infections in Italian children suffering from asthma or wheezing compared with healthy subjects and to estimate the association between incremental increases in principal pollutants and the incidence of respiratory symptoms. METHODS: This prospective study enrolled 777 children aged 2 to 18 years (375 with recurrent wheezing or asthma and 402 healthy subjects). Over 12 months, parents filled out a daily clinical diary to report information about respiratory symptoms, type of medication used and healthcare utilization. Clinical data were combined with the results obtained using an air pollution monitoring system of the five most common pollutants. RESULTS: Among the 329 children with recurrent wheezing or asthma and 364 healthy subjects who completed follow-up, children with recurrent wheezing or asthma reported significantly more days of fever (p=0.005) and cough (p<0.001), episodes of rhinitis (p=0.04) and tracheitis (p=0.01), asthma attacks (p<0.001), episodes of pneumonia (p<0.001) and hospitalizations (p=0.02). In the wheezing/asthma cohort, living close to the street with a high traffic density was a risk factor for asthma exacerbations (odds ratio [OR]=1.79; 95% confidence interval [CI], 1.13-2.84), whereas living near green areas was found to be protective (OR=0.50; 95% CI, 0.31 -0.80). An increase of 10 µg/m3 of particulates less than 10 microns in diameter (PM10) and nitrogen dioxide (NO2) increased the onset of pneumonia only in wheezing/asthmatic children (continuous rate ratio [RR]=1.08, 95% CI: 1.00-1.17 for PM10; continuous RR=1.08, 95% CI: 1.01-1.17 for NO2). CONCLUSIONS: There is a significant association between traffic-related pollution and the development of asthma exacerbations and respiratory infections in children born to atopic parents and in those suffering from recurrent wheezing or asthma. These findings suggest that environmental control may be crucial for respiratory health in children with underlying respiratory disease.