Association of Radiology Findings with Etiology of Community Acquired Pneumonia among Children.

OBJECTIVE: To evaluate the association between consolidation on chest radiograph and typical bacterial etiology of childhood community acquired pneumonia (CAP) in the Etiology of Pneumonia in the Community study. STUDY DESIGN: Hospitalized children <18 years of age with CAP enrolled in the Etiology of Pneumonia in the Community study at 3 children's hospitals between January 2010 and June 2012 were included. Testing of blood and respiratory specimens used multiple modalities to identify typical and atypical bacterial, or viral infection. Study radiologists classified chest radiographs (consolidation, other infiltrates [interstitial and/or alveolar], pleural effusion) using modified World Health Organization pneumonia criteria. Infiltrate patterns were compared according to etiology of CAP. RESULTS: Among 2212 children, there were 1302 (59%) with consolidation with or without other infiltrates, 910 (41%) with other infiltrates, and 296 (13%) with pleural effusion. In 1795 children, at least 1 pathogen was detected. Among these patients, consolidation (74%) was the most frequently observed pattern (74% in typical bacterial CAP, 58% in atypical bacterial CAP, and 54% in viral CAP). Positive and negative predictive values of consolidation for typical bacterial CAP were 12% (95% CI 10%-15%) and 96% (95% CI 95%-97%) respectively. In a multivariable model, typical bacterial CAP was associated with pleural effusion (OR 7.3, 95% CI 4.7-11.2) and white blood cell ≥15 000/mL (OR 3.2, 95% CI 2.2-4.9), and absence of wheeze (OR 0.5, 95% CI 0.3-0.8) or viral detection (OR 0.2, 95% CI 0.1-0.4). CONCLUSIONS: Consolidation predicted typical bacterial CAP poorly, but its absence made typical bacterial CAP unlikely. Pleural effusion was the best predictor of typical bacterial infection, but too uncommon to aid etiology prediction.

Parainfluenza Virus Types 1-3 Infections Among Children and Adults Hospitalized With Community-acquired Pneumonia.

BACKGROUND: Parainfluenza virus (PIV) is a leading cause of lower respiratory tract infections. Although there are several distinct PIV serotypes, few studies have compared the clinical characteristics and severity of infection among the individual PIV serotypes and between PIV and other pathogens in patients with community-acquired pneumonia. METHODS: We conducted active population-based surveillance for radiographically confirmed community-acquired pneumonia hospitalizations among children and adults in 8 US hospitals with systematic collection of clinical data and respiratory, blood, and serological specimens for pathogen detection. We compared clinical features of PIV-associated pneumonia among individual serotypes 1, 2, and 3 and among all PIV infections with other viral, atypical, and bacterial pneumonias. We also compared in-hospital disease severity among groups employing an ordinal scale (mild, moderate, severe) using multivariable proportional odds regression. RESULTS: PIV was more commonly detected in children (155/2354; 6.6%) than in adults (66/2297; 2.9%) (P < .001). Other pathogens were commonly co-detected among PIV cases (110/221; 50%). Clinical features of PIV-1, PIV-2, and PIV-3 infections were similar to one another in both children and adults with pneumonia. In multivariable analysis, children with PIV-associated pneumonia exhibited similar severity to children with other nonbacterial pneumonia, whereas children with bacterial pneumonia exhibited increased severity (odds ratio, 8.42; 95% confidence interval, 1.88-37.80). In adults, PIV-associated pneumonia exhibited similar severity to other pneumonia pathogens. CONCLUSIONS: Clinical features did not distinguish among infection with individual PIV serotypes in patients hospitalized with community-acquired pneumonia. However, in children, PIV pneumonia was less severe than bacterial pneumonia.

Clinical Features of Human Metapneumovirus-Associated Community-acquired Pneumonia Hospitalizations.

BACKGROUND: Human metapneumovirus (HMPV) is a leading cause of respiratory tract infections. Few studies have compared the clinical characteristics and severity of HMPV-associated pneumonia with other pathogens. METHODS: Active, population-based surveillance was previously conducted for radiographically confirmed, community-acquired pneumonia hospitalizations among children and adults in 8 United States hospitals. Clinical data and specimens for pathogen detection were systematically collected. We described clinical features of all HMPV-associated pneumonia and, after excluding codetections with other pathogen types, we compared features of HMPV-associated pneumonia with other viral, atypical, and bacterial pneumonia and modeled the severity (mild, moderate, and severe) and length of stay using multivariable proportional odds regression. RESULTS: HMPV was detected in 298/2358 (12.6%) children and 88/2320 (3.8%) adults hospitalized with pneumonia and was commonly codetected with other pathogens (125/298 [42%] children and 21/88 [24%] adults). Fever and cough were the most common presenting symptoms of HMPV-associated pneumonia and were also common symptoms of other pathogens. After excluding codetections in children (n = 1778), compared to HMPV (reference), bacterial pneumonia exhibited increased severity (odds ratio [OR], 3.66; 95% confidence interval [CI], 1.43-9.40), respiratory syncytial virus (RSV; OR, 0.76; 95% CI, .59-.99) and atypical (OR, 0.39; 95% CI, .19-.81) infections exhibited decreased severity, and other viral pneumonia exhibited similar severity (OR, 0.88; 95% CI, .55-1.39). In adults (n = 2145), bacterial (OR, 3.74; 95% CI, 1.87-7.47) and RSV pneumonia (OR, 1.82; 95% CI, 1.32-2.50) were more severe than HMPV (reference), but all other pathogens had similar severity. CONCLUSIONS: Clinical features did not reliably distinguish HMPV-associated pneumonia from other pathogens. HMPV-associated pneumonia was less severe than bacterial and adult RSV pneumonia, but was otherwise as or more severe than other common pathogens.

Mycoplasma pneumoniae Among Children Hospitalized With Community-acquired Pneumonia.

Background: The epidemiology of Mycoplasma pneumoniae (Mp) among US children (<18 years) hospitalized with community-acquired pneumonia (CAP) is poorly understood. Methods: In the Etiology of Pneumonia in the Community study, we prospectively enrolled 2254 children hospitalized with radiographically confirmed pneumonia from January 2010-June 2012 and tested nasopharyngeal/oropharyngeal swabs for Mp using real-time polymerase chain reaction (PCR). Clinical and epidemiological features of Mp PCR-positive and -negative children were compared using logistic regression. Macrolide susceptibility was assessed by genotyping isolates. Results: One hundred and eighty two (8%) children were Mp PCR-positive (median age, 7 years); 12% required intensive care and 26% had pleural effusion. No in-hospital deaths occurred. Macrolide resistance was found in 4% (6/169) isolates. Of 178 (98%) Mp PCR-positive children tested for copathogens, 50 (28%) had ≥1 copathogen detected. Variables significantly associated with higher odds of Mp detection included age (10-17 years: adjusted odds ratio [aOR], 10.7 [95% confidence interval {CI}, 5.4-21.1] and 5-9 years: aOR, 6.4 [95% CI, 3.4-12.1] vs 2-4 years), outpatient antibiotics ≤5 days preadmission (aOR, 2.3 [95% CI, 1.5-3.5]), and copathogen detection (aOR, 2.1 [95% CI, 1.3-3.3]). Clinical characteristics were non-specific. Conclusions: Usually considered as a mild respiratory infection, Mp was the most commonly detected bacteria among children aged ≥5 years hospitalized with CAP, one-quarter of whom had codetections. Although associated with clinically nonspecific symptoms, there was a need for intensive care in some cases. Mycoplasma pneumoniae should be included in the differential diagnosis for school-aged children hospitalized with CAP.

Etiology and Impact of Coinfections in Children Hospitalized With Community-Acquired Pneumonia.

Background: Recognition that coinfections are common in children with community-acquired pneumonia (CAP) is increasing, but gaps remain in our understanding of their frequency and importance. Methods: We analyzed data from 2219 children hospitalized with CAP and compared demographic and clinical characteristics and outcomes between groups with viruses alone, bacteria alone, or coinfections. We also assessed the frequency of selected pairings of codetected pathogens and their clinical characteristics. Results: A total of 576 children (26%) had a coinfection. Children with only virus detected were younger, more likely to be black, and more likely to have comorbidities such as asthma, compared with children infected with typical bacteria alone. Children with virus-bacterium coinfections had a higher frequency of leukocytosis, consolidation on chest radiography, parapneumonic effusions, intensive care unit admission, and need for mechanical ventilation and an increased length of stay, compared with children infected with viruses alone. Virus-virus coinfections were generally comparable to single-virus infections, with the exception of the need for oxygen supplementation, which was higher during the first 24 hours of hospitalization in some virus-virus pairings. Conclusions: Coinfections occurred in 26% of children hospitalized for CAP. Children with typical bacterial infections, alone or complicated by a viral infection, have worse outcomes than children infected with a virus alone.

Community-Acquired Pneumonia Requiring Hospitalization among U.S. Adults.

BACKGROUND: Community-acquired pneumonia is a leading infectious cause of hospitalization and death among U.S. adults. Incidence estimates of pneumonia confirmed radiographically and with the use of current laboratory diagnostic tests are needed. METHODS: We conducted active population-based surveillance for community-acquired pneumonia requiring hospitalization among adults 18 years of age or older in five hospitals in Chicago and Nashville. Patients with recent hospitalization or severe immunosuppression were excluded. Blood, urine, and respiratory specimens were systematically collected for culture, serologic testing, antigen detection, and molecular diagnostic testing. Study radiologists independently reviewed chest radiographs. We calculated population-based incidence rates of community-acquired pneumonia requiring hospitalization according to age and pathogen. RESULTS: From January 2010 through June 2012, we enrolled 2488 of 3634 eligible adults (68%). Among 2320 adults with radiographic evidence of pneumonia (93%), the median age of the patients was 57 years (interquartile range, 46 to 71); 498 patients (21%) required intensive care, and 52 (2%) died. Among 2259 patients who had radiographic evidence of pneumonia and specimens available for both bacterial and viral testing, a pathogen was detected in 853 (38%): one or more viruses in 530 (23%), bacteria in 247 (11%), bacterial and viral pathogens in 59 (3%), and a fungal or mycobacterial pathogen in 17 (1%). The most common pathogens were human rhinovirus (in 9% of patients), influenza virus (in 6%), and Streptococcus pneumoniae (in 5%). The annual incidence of pneumonia was 24.8 cases (95% confidence interval, 23.5 to 26.1) per 10,000 adults, with the highest rates among adults 65 to 79 years of age (63.0 cases per 10,000 adults) and those 80 years of age or older (164.3 cases per 10,000 adults). For each pathogen, the incidence increased with age. CONCLUSIONS: The incidence of community-acquired pneumonia requiring hospitalization was highest among the oldest adults. Despite current diagnostic tests, no pathogen was detected in the majority of patients. Respiratory viruses were detected more frequently than bacteria. (Funded by the Influenza Division of the National Center for Immunizations and Respiratory Diseases.).

Community-acquired pneumonia requiring hospitalization among U.S. children.

BACKGROUND: Incidence estimates of hospitalizations for community-acquired pneumonia among children in the United States that are based on prospective data collection are limited. Updated estimates of pneumonia that has been confirmed radiographically and with the use of current laboratory diagnostic tests are needed. METHODS: We conducted active population-based surveillance for community-acquired pneumonia requiring hospitalization among children younger than 18 years of age in three hospitals in Memphis, Nashville, and Salt Lake City. We excluded children with recent hospitalization or severe immunosuppression. Blood and respiratory specimens were systematically collected for pathogen detection with the use of multiple methods. Chest radiographs were reviewed independently by study radiologists. RESULTS: From January 2010 through June 2012, we enrolled 2638 of 3803 eligible children (69%), 2358 of whom (89%) had radiographic evidence of pneumonia. The median age of the children was 2 years (interquartile range, 1 to 6); 497 of 2358 children (21%) required intensive care, and 3 (<1%) died. Among 2222 children with radiographic evidence of pneumonia and with specimens available for bacterial and viral testing, a viral or bacterial pathogen was detected in 1802 (81%), one or more viruses in 1472 (66%), bacteria in 175 (8%), and both bacterial and viral pathogens in 155 (7%). The annual incidence of pneumonia was 15.7 cases per 10,000 children (95% confidence interval [CI], 14.9 to 16.5), with the highest rate among children younger than 2 years of age (62.2 cases per 10,000 children; 95% CI, 57.6 to 67.1). Respiratory syncytial virus was more common among children younger than 5 years of age than among older children (37% vs. 8%), as were adenovirus (15% vs. 3%) and human metapneumovirus (15% vs. 8%). Mycoplasma pneumoniae was more common among children 5 years of age or older than among younger children (19% vs. 3%). CONCLUSIONS: The burden of hospitalization for children with community-acquired pneumonia was highest among the very young, with respiratory viruses the most commonly detected causes of pneumonia. (Funded by the Influenza Division of the National Center for Immunization and Respiratory Diseases.).

Human Bocavirus Capsid Messenger RNA Detection in Children With Pneumonia.

Background: The role of human bocavirus (HBoV) in respiratory illness is uncertain. HBoV genomic DNA is frequently detected in both ill and healthy children. We hypothesized that spliced viral capsid messenger RNA (mRNA) produced during active replication might be a better marker for acute infection. Methods: As part of the Etiology of Pneumonia in the Community (EPIC) study, children aged <18 years who were hospitalized with community-acquired pneumonia (CAP) and children asymptomatic at the time of elective outpatient surgery (controls) were enrolled. Nasopharyngeal/oropharyngeal specimens were tested for HBoV mRNA and genomic DNA by quantitative polymerase chain reaction. Results: HBoV DNA was detected in 10.4% of 1295 patients with CAP and 7.5% of 721 controls (odds ratio [OR], 1.4 [95% confidence interval {CI}, 1.0-2.0]); HBoV mRNA was detected in 2.1% and 0.4%, respectively (OR, 5.1 [95% CI, 1.6-26]). When adjusted for age, enrollment month, and detection of other respiratory viruses, HBoV mRNA detection (adjusted OR, 7.6 [95% CI, 1.5-38.4]) but not DNA (adjusted OR, 1.2 [95% CI, .6-2.4]) was associated with CAP. Among children with no other pathogens detected, HBoV mRNA (OR, 9.6 [95% CI, 1.9-82]) was strongly associated with CAP. Conclusions: Detection of HBoV mRNA but not DNA was associated with CAP, supporting a pathogenic role for HBoV in CAP. HBoV mRNA could be a useful target for diagnostic testing.

Viral Pathogen Detection by Metagenomics and Pan-Viral Group Polymerase Chain Reaction in Children With Pneumonia Lacking Identifiable Etiology.

Background: Community-acquired pneumonia (CAP) is a leading cause of pediatric hospitalization. Pathogen identification fails in approximately 20% of children but is critical for optimal treatment and prevention of hospital-acquired infections. We used two broad-spectrum detection strategies to identify pathogens in test-negative children with CAP and asymptomatic controls. Methods: Nasopharyngeal/oropharyngeal (NP/OP) swabs from 70 children <5 years with CAP of unknown etiology and 90 asymptomatic controls were tested by next-generation sequencing (RNA-seq) and pan viral group (PVG) PCR for 19 viral families. Association of viruses with CAP was assessed by adjusted odds ratios (aOR) and 95% confidence intervals controlling for season and age group. Results: RNA-seq/PVG PCR detected previously missed, putative pathogens in 34% of patients. Putative viral pathogens included human parainfluenza virus 4 (aOR 9.3, P = .12), human bocavirus (aOR 9.1, P < .01), Coxsackieviruses (aOR 5.1, P = .09), rhinovirus A (aOR 3.5, P = .34), and rhinovirus C (aOR 2.9, P = .57). RNA-seq was more sensitive for RNA viruses whereas PVG PCR detected more DNA viruses. Conclusions: RNA-seq and PVG PCR identified additional viruses, some known to be pathogenic, in NP/OP specimens from one-third of children hospitalized with CAP without a previously identified etiology. Both broad-range methods could be useful tools in future epidemiologic and diagnostic studies.

Rhinovirus Viremia in Patients Hospitalized With Community-Acquired Pneumonia.

Background: Rhinoviruses (RVs) are ubiquitous respiratory pathogens that often cause mild or subclinical infections. Molecular detection of RVs from the upper respiratory tract can be prolonged, complicating etiologic association in persons with severe lower respiratory tract infections. Little is known about RV viremia and its value as a diagnostic indicator in persons hospitalized with community-acquired pneumonia (CAP). Methods: Sera from RV-positive children and adults hospitalized with CAP were tested for RV by real-time reverse-transcription polymerase chain reaction. Rhinovirus species and type were determined by partial genome sequencing. Results: Overall, 57 of 570 (10%) RV-positive patients were viremic, and all were children aged <10 years (n = 57/375; 15.2%). Although RV-A was the most common RV species detected from respiratory specimens (48.8%), almost all viremias were RV-C (98.2%). Viremic patients had fewer codetected pathogens and were more likely to have chest retractions, wheezing, and a history of underlying asthma/reactive airway disease than patients without viremia. Conclusions: More than 1 out of 7 RV-infected children aged <10 years hospitalized with CAP were viremic. In contrast with other RV species, RV-C infections were highly associated with viremia and were usually the only respiratory pathogen identified, suggesting that RV-C viremia may be an important diagnostic indicator in pediatric pneumonia.

Relationship Between Body Mass Index and Outcomes Among Hospitalized Patients With Community-Acquired Pneumonia.

Background: The effect of body mass index (BMI) on community-acquired pneumonia (CAP) severity is unclear. Methods: We investigated the relationship between BMI and CAP outcomes (hospital length of stay [LOS], intensive care unit [ICU] admission, and invasive mechanical ventilation) in hospitalized CAP patients from the Centers for Disease Control and Prevention Etiology of Pneumonia in the Community (EPIC) study, adjusting for age, demographics, underlying conditions, and smoking status (adults only). Results: Compared with normal-weight children, odds of ICU admission were higher in children who were overweight (adjusted odds ratio [aOR], 1.7; 95% confidence interval [CI], 1.1-2.8) or obese (aOR, 2.1; 95% CI, 1.4-3.2), and odds of mechanical ventilation were higher in children with obesity (aOR, 2.7; 95% CI, 1.3-5.6). When stratified by asthma (presence/absence), these findings remained significant only in children with asthma. Compared with normal-weight adults, odds of LOS >3 days were higher in adults who were underweight (aOR, 1.6; 95% CI, 1.1-2.4), and odds of mechanical ventilation were lowest in adults who were overweight (aOR, 0.5; 95% CI, .3-.9). Conclusions: Children who were overweight or obese, particularly those with asthma, had higher odds of ICU admission or mechanical ventilation. In contrast, adults who were underweight had longer LOS. These results underscore the complex relationship between BMI and CAP outcomes.

Serology Enhances Molecular Diagnosis of Respiratory Virus Infections Other than Influenza in Children and Adults Hospitalized with Community-Acquired Pneumonia.

Both molecular and serological assays have been used previously to determine the etiology of community-acquired pneumonia (CAP). However, the extent to which these methods are correlated and the added diagnostic value of serology for respiratory viruses other than influenza virus have not been fully evaluated. Using data from patients enrolled in the Centers for Disease Control and Prevention (CDC) Etiology of Pneumonia in the Community (EPIC) study, we compared real-time reverse transcription-PCR (RT-PCR) and serology for the diagnosis of respiratory syncytial virus (RSV), human metapneumovirus (HMPV), parainfluenza virus 1 to 3 (PIV1, PIV2, and PIV3), and adenovirus (AdV) infections. Of 5,126 patients enrolled, RT-PCR and serology test results were available for 2,023, including 1,087 children below the age of 18 years and 936 adults. For RSV, 287 (14.2%) patients were positive by RT-PCR and 234 (11.6%) were positive by serology; for HMPV, 172 (8.5%) tested positive by RT-PCR and 147 (7.3%) by serology; for the PIVs, 94 (4.6%) tested positive by RT-PCR and 92 (4.6%) by serology; and for AdV, 111 (5.5%) tested positive by RT-PCR and 62 (3.1%) by serology. RT-PCR provided the highest number of positive detections overall, but serology increased diagnostic yield for RSV (by 11.8%), HMPV (by 25.0%), AdV (by 32.4%), and PIV (by 48.9%). The method concordance estimated by Cohen's kappa coefficient (κ) ranged from good (for RSV; κ = 0.73) to fair (for AdV; κ = 0.27). Heterotypic seroresponses observed between PIVs and persistent low-level AdV shedding may account for the higher method discordance observed with each of these viruses. Serology can be a helpful adjunct to RT-PCR for research-based assessment of the etiologic contribution of respiratory viruses other than influenza virus to CAP.

Respiratory Viral Detection in Children and Adults: Comparing Asymptomatic Controls and Patients With Community-Acquired Pneumonia.

BACKGROUND: The clinical significance of viruses detected in patients with community-acquired pneumonia (CAP) is often unclear. METHODS: We conducted a prospective study to identify the prevalence of 13 viruses in the upper respiratory tract of patients with CAP and concurrently enrolled asymptomatic controls with real-time reverse-transcriptase polymerase chain reaction. We compared age-stratified prevalence of each virus between patients with CAP and controls and used multivariable logistic regression to calculate attributable fractions (AFs). RESULTS: We enrolled 1024 patients with CAP and 759 controls. Detections of influenza, respiratory syncytial virus, and human metapneumovirus were substantially more common in patients with CAP of all ages than in controls (AFs near 1.0). Parainfluenza and coronaviruses were also more common among patients with CAP (AF, 0.5-0.75). Rhinovirus was associated with CAP among adults (AF, 0.93) but not children (AF, 0.02). Adenovirus was associated with CAP only among children <2 years old (AF, 0.77). CONCLUSIONS: The probability that a virus detected with real-time reverse-transcriptase polymerase chain reaction in patients with CAP contributed to symptomatic disease varied by age group and specific virus. Detections of influenza, respiratory syncytial virus, and human metapneumovirus among patients with CAP of all ages probably indicate an etiologic role, whereas detections of parainfluenza, coronaviruses, rhinovirus, and adenovirus, especially in children, require further scrutiny.

Clinical and Epidemiological Evidence of the Red Queen Hypothesis in Pneumococcal Serotype Dynamics.

BACKGROUND: The Red Queen hypothesis is an evolutionary theory that describes the reciprocal coevolution of competing species. We sought to study whether introduction of the 7- and 13-valent pneumococcal conjugate vaccines (PCV7 and PCV13, respectively) altered pneumococcal serotype dynamics among children with invasive pneumococcal disease (IPD) as predicted by the Red Queen hypothesis. METHODS: This study examined pneumococcal isolates (n = 641) obtained from children <18 years of age hospitalized with IPD from 1997 to 2014 in Utah. A review of the literature also identified several additional studies conducted in the United States and Europe that were used to test the external generalizability of our Utah findings. Simpson's index was used to quantify pneumococcal serotype diversity. RESULTS: In Utah, the introduction of PCV7 and PCV13 was associated with rapid increases in serotype diversity (P < .001). Serotypes rarely present before vaccine introduction emerged as common causes of IPD. Diversity then decreased (P < .001) as competition selected for the fittest serotypes and new evolutionary equilibriums were established. This pattern was also observed more broadly in the United States, the United Kingdom, Norway, and Spain. CONCLUSIONS: This vaccine-driven example of human/bacterial coevolution appears to confirm the Red Queen hypothesis, which reveals a limitation of serotype-specific vaccines and offers insights that may facilitate alternative strategies for the elimination of IPD.

Community-Acquired Pneumonia Hospitalization among Children with Neurologic Disorders.

OBJECTIVE: To describe and compare the clinical characteristics, outcomes, and etiology of pneumonia among children hospitalized with community-acquired pneumonia (CAP) with neurologic disorders, non-neurologic underlying conditions, and no underlying conditions. STUDY DESIGN: Children <18 years old hospitalized with clinical and radiographic CAP were enrolled at 3 US children's hospitals. Neurologic disorders included cerebral palsy, developmental delay, Down syndrome, epilepsy, non-Down syndrome chromosomal abnormalities, and spinal cord abnormalities. We compared the epidemiology, etiology, and clinical outcomes of CAP in children with neurologic disorders with those with non-neurologic underlying conditions, and those with no underlying conditions using bivariate, age-stratified, and multivariate logistic regression analyses. RESULTS: From January 2010-June 2012, 2358 children with radiographically confirmed CAP were enrolled; 280 (11.9%) had a neurologic disorder (52.1% of these individuals also had non-neurologic underlying conditions), 934 (39.6%) had non-neurologic underlying conditions only, and 1144 (48.5%) had no underlying conditions. Children with neurologic disorders were older and more likely to require intensive care unit (ICU) admission than children with non-neurologic underlying conditions and children with no underlying conditions; similar proportions were mechanically ventilated. In age-stratified analysis, children with neurologic disorders were less likely to have a pathogen detected than children with non-neurologic underlying conditions. In multivariate analysis, having a neurologic disorder was associated with ICU admission for children ≥2 years of age. CONCLUSIONS: Children with neurologic disorders hospitalized with CAP were less likely to have a pathogen detected and more likely to be admitted to the ICU than children without neurologic disorders.

Community Surveillance of Respiratory Viruses Among Families in the Utah Better Identification of Germs-Longitudinal Viral Epidemiology (BIG-LoVE) Study.

BACKGROUND: This study: (1) describes the viral etiology of respiratory illness by prospectively collecting weekly symptom diaries and nasal swabs from families for 1 year, (2) analyzed data by reported symptoms, virus, age, and family composition, and (3) evaluated the duration of virus detection. METHODS: Twenty-six households (108 individuals) provided concurrent symptom and nasal swab data for 4166 person-weeks. The FilmArray polymerase chain reaction (PCR) platform (BioFire Diagnostics, LLC) was used to detect 16 respiratory viruses. Viral illnesses were defined as ≥1 consecutive weeks with the same virus detected with symptoms reported in ≥1 week. RESULTS: Participants reported symptoms in 23% and a virus was detected in 26% of person-weeks. Children younger than 5 years reported symptoms more often and were more likely to have a virus detected than older participants (odds ratio [OR] 2.47, 95% confidence interval [CI], 2.08-2.94 and OR 3.96, 95% CI, 3.35-4.70, respectively). Compared with single person households, individuals living with children experienced 3 additional weeks of virus detection. There were 783 viral detection episodes; 440 (56%) associated with symptoms. Coronaviruses, human metapneumovirus, and influenza A detections were usually symptomatic; bocavirus and rhinovirus detections were often asymptomatic. The mean duration of PCR detection was ≤2 weeks for all viruses and detections of ≥3 weeks occurred in 16% of episodes. Younger children had longer durations of PCR detection. CONCLUSIONS: Viral detection is often asymptomatic and occasionally prolonged, especially for bocavirus and rhinovirus. In clinical settings, the interpretation of positive PCR tests, particularly in young children and those who live with them, may be confounded.

Secondhand Smoke Exposure and Illness Severity among Children Hospitalized with Pneumonia.

OBJECTIVE: To assess the relationship between secondhand smoke (SHS) exposure and disease severity among children hospitalized with community-acquired pneumonia (CAP). STUDY DESIGN: Children hospitalized with clinical and radiographic CAP were enrolled between January 1, 2010, and June 30, 2012 at 3 hospitals in Tennessee and Utah as part of the Centers for Disease Control and Prevention's Etiology of Pneumonia in the Community study. Household SHS exposure was defined based on the number of smokers in the child's home. Outcomes included hospital length of stay, intensive care unit admission, and mechanical ventilation. Proportional hazards and logistic regression models were used to assess associations between SHS exposure and outcomes. All models were adjusted for age, sex, race/ethnicity, household education level, government insurance, comorbidities, enrollment site, year, and season. RESULTS: Of the 2219 children included in the study, SHS exposure was reported in 785 (35.4%), including 325 (14.8%) with ≥2 smokers in the home. Compared with nonexposed children, the children exposed to ≥2 smokers had longer length of stay (median, 70.4 hours vs 64.4 hours; adjusted hazard ratio, 0.85; 95% CI, 0.75-0.97) and were more likely to receive intensive care (25.2% vs 20.9%; aOR, 1.44; 95% CI, 1.05-1.96), but not mechanical ventilation. Outcomes in children exposed to only 1 household smoker were similar to those in nonexposed children. CONCLUSION: Children hospitalized with CAP from households with ≥2 smokers had a longer length of stay and were more likely to require intensive care compared with children from households with no smokers, suggesting that they experienced greater pneumonia severity.

Association Between Hospitalization With Community-Acquired Laboratory-Confirmed Influenza Pneumonia and Prior Receipt of Influenza Vaccination.

IMPORTANCE: Few studies have evaluated the relationship between influenza vaccination and pneumonia, a serious complication of influenza infection. OBJECTIVE: To assess the association between influenza vaccination status and hospitalization for community-acquired laboratory-confirmed influenza pneumonia. DESIGN, SETTING, AND PARTICIPANTS: The Etiology of Pneumonia in the Community (EPIC) study was a prospective observational multicenter study of hospitalizations for community-acquired pneumonia conducted from January 2010 through June 2012 at 4 US sites. In this case-control study, we used EPIC data from patients 6 months or older with laboratory-confirmed influenza infection and verified vaccination status during the influenza seasons and excluded patients with recent hospitalization, from chronic care residential facilities, and with severe immunosuppression. Logistic regression was used to calculate odds ratios, comparing the odds of vaccination between influenza-positive (case) and influenza-negative (control) patients with pneumonia, controlling for demographics, comorbidities, season, study site, and timing of disease onset. Vaccine effectiveness was estimated as (1 - adjusted odds ratio) × 100%. EXPOSURE: Influenza vaccination, verified through record review. MAIN OUTCOMES AND MEASURES: Influenza pneumonia, confirmed by real-time reverse-transcription polymerase chain reaction performed on nasal/oropharyngeal swabs. RESULTS: Overall, 2767 patients hospitalized for pneumonia were eligible for the study; 162 (5.9%) had laboratory-confirmed influenza. Twenty-eight of 162 cases (17%) with influenza-associated pneumonia and 766 of 2605 controls (29%) with influenza-negative pneumonia had been vaccinated. The adjusted odds ratio of prior influenza vaccination between cases and controls was 0.43 (95% CI, 0.28-0.68; estimated vaccine effectiveness, 56.7%; 95% CI, 31.9%-72.5%). CONCLUSIONS AND RELEVANCE: Among children and adults hospitalized with community-acquired pneumonia, those with laboratory-confirmed influenza-associated pneumonia, compared with those with pneumonia not associated with influenza, had lower odds of having received influenza vaccination.

Pharmacokinetic and pharmacodynamic optimisation of intravenous tobramycin dosing among children with cystic fibrosis.

This study aimed to characterize the pharmacokinetics of tobramycin administered one, two, or three times daily and to develop an optimal dosing scheme for children with cystic fibrosis. Therapeutic drug monitoring data were obtained from children hospitalized at three academic medical centres from 2006 to 2012. Population pharmacokinetic models were constructed using NONMEM 7.2. Model-based simulations were performed in Matlab R2012b to identify optimal dosing regimens using pharmacodynamic targets. The pharmacokinetic analysis involved 257 patients with a median age of 8.1 years (range 0.1-18.8). Clearance was estimated as 5.59 L/h and the volume of distribution was 18.90 L. Mean (±SD) maximum serum concentrations were highest among patients dosed once per day (24.1 ± 8.9 µg/mL) and were lower among patients dosed two and three times per day (11.2 ± 1.4 and 8.1 ± 2.4 µg/mL, respectively). Simulations revealed that once daily dosing was the only effective regimen for a Pseudomonas aeruginosa MIC of 1.5 µg/mL and none of the tested regimens reliably achieved the pharmacodynamic target for MICs ≥2 µg/mL. Once daily dosing resulted in higher maximum serum concentrations when compared to multiple-daily dosing. In simulations, once daily dosing was the only regimen to achieve the pharmacodynamic target for all subjects with MICs <2 µg/mL.

The impact of human rhinovirus infection in pediatric patients undergoing heart surgery.

Human rhinovirus (HRV), the most common cause of upper respiratory infection in children, can present as bronchiolitis, pneumonia, or asthma exacerbations. The impact of HRV in infants and toddlers with congenital heart disease is poorly defined. A case-control study was performed to compare the clinical course for 19 young children with respiratory symptoms who tested positive for rhinovirus after heart surgery with that of 56 matched control subjects. The control subjects were matched by surgical repair, age, weight, and time of the year. Patients with known HRVs before surgery and control subjects with respiratory symptoms or positive test results for viruses were excluded from the study. Human rhinovirus infection was associated with more than a tenfold increase in the odds of noninvasive ventilation after extubation (odds ratio [OR] 11.45; 95 % confidence interval [CI] 3.97-38.67), a 12-fold increase in the probability of extubation failure (OR 12.84; 95 % CI 2.93-56.29), and increased use of pulmonary medications including bronchodilator and nitric oxide (p < 0.001). As a result, the hospital length of stay (HLOS) was two times longer than for the control subjects (p < 0.001), and the cardiac intensive care unit (CICU) length of stay (CICU LOS) was three times longer (p < 0.0001). The intubation time was significantly longer (p < 0.001), and the CICU respiratory charges were significantly greater (p = 0.001) for the infected patients. Human rhinovirus increases resource use and prolongs postoperative recovery after pediatric heart surgery. Surgery timing should be delayed for patients with rhinovirus if possible.