<Emphasis Type="Italic">Bordetella Pertussis</Emphasis> Infection in Hospitalized Infants with Acute Bronchiolitis

Objective

To assess the frequency of B. pertussis infection among young infants hospitalized with acute bronchiolitis and to determine whether B. pertussis infection affects the clinical course of acute bronchiolitis.

Methods

A total of 172 infants <6 months of age hospitalized with acute bronchiolitis were tested for B. pertussis and respiratory viruses with real-time PCR. Cases were divided into 2 groups according to B. pertussis positive or negative. Clinical parameters, clinical severity scores and laboratory characteristics of the pertussis-positive and pertussis-negative cases were compared.

Results

Bordetella pertussis infection was detected in 44 (25.6%) of the 172 infants hospitalized for acute bronchiolitis, and as co-infection with respiratory viral agents in 27 (61.4%) infants. Of the 44 pertussis-positive infants, only 17 (38.6%) experienced a paroxysmal cough, 13 (29.5%) had whooping and 15 (34.1%) had post-tussive vomiting. There was no significant difference between pertussis-positive and pertussis-negative infants according to Wang clinical score at admission (4.9 ± 1.5 vs. 5.2 ± 2.5; p = 0.689). The overall disease severity score was also similar between the two groups (6.5 ± 1.4 vs. 6.9 ± 1.6; p = 0.095).

Conclusions

Bordetella pertussis infection is common in young infants hospitalized for acute bronchiolitis, mostly as co-infection with respiratory viruses. The clinical features of pertussis in the infants are not characteristic. Viral bronchiolitis and pertussis cases could not be differentiated by clinical findings. Co-infection with pertussis did not affect the clinical outcome in infants hospitalized with acute bronchiolitis.

     

Rhinoviruses as critical agents in severe bronchiolitis in infants

ObjectivesTo detect RSV or other thirteen respiratory viruses as possible causer agent of bronchiolitis in infants.MethodThis is an epidemiological analytical study, conducted using a nasopharyngeal aspirate of 173 hospitalized children younger than two years old with severe bronchiolitis in three hospitals in the Campinas Metropolitan Region (CMR) during 2013-14. The data was statically evaluated by Pearson's chi-squared test with statistical significance of 0.05 and 95% confidence level.ResultsAs expected, the most prevalent viruses detected were RSV A and B in 47% and 16% of the samples, respectively. However, almost a third of severe bronchiolitis cases there were no detection of RSV, and the viruses more commonly detected were rhinoviruses, which were identified in almost a quarter of all positive samples for at least a viral agent.ConclusionsAlthough nothing could be concluded from the disease severity and clinical-epidemiological data, the present study's results indicate that severe bronchiolitis is not always related to RSV infections in children younger than two years old, and the rhinoviruses were more prevalent in these cases. These findings reinforce the need to carry out a viral diagnosis in the hospital emergency would be very appropriate for all cases of respiratory infections in children, even for diseases in which the primary etiological agent seems to be well known.     

Acute respiratory viral infections in pediatric cancer patients undergoing chemotherapy

Objectiveto estimate the prevalence of infection by respiratory viruses in pediatric patients with cancer and acute respiratory infection (ARI) and/or fever.Methodscross-sectional study, from January 2011 to December 2012. The secretions of nasopharyngeal aspirates were analyzed in children younger than 21 years with acute respiratory infections. Patients were treated at the Grupo em Defesa da Criança Com Câncer (Grendacc) and University Hospital (HU), Jundiaí, SP. The rapid test was used for detection of influenza virus (Kit Biotrin, Inc. Ireland), and real-time multiplex polymerase chain reaction (FTD, Respiratory pathogens, multiplex Fast Trade Kit, Malta) for detection of influenza virus (H1N1, B), rhinovirus, parainfluenza virus, adenovirus, respiratory syncytial virus, human parechovirus, bocavirus, metapneumovirus, and human coronavirus. The prevalence of viral infection was estimated and association tests were used (χ² or Fisher's exact test).Results104 samples of nasopharyngeal aspirate and blood were analyzed. The median age was 12 ± 5.2 years, 51% males, 68% whites, 32% had repeated ARIs, 32% prior antibiotic use, 19.8% cough, and 8% contact with ARIs. A total of 94.3% were in good general status. Acute lymphocytic leukemia (42.3%) was the most prevalent neoplasia. Respiratory viruses were detected in 50 samples: rhinoviruses (23.1%), respiratory syncytial virus AB (8.7%), and coronavirus (6.8%). Co-detection occurred in 19% of cases with 2 viruses and in 3% of those with 3 viruses, and was more frequent between rhinovirus and coronavirus 43. Fever in neutropenic patients was observed in 13%, of which four (30.7) were positive for viruses. There were no deaths.Conclusionsthe prevalence of respiratory viruses was relevant in the infectious episode, with no increase in morbidity and mortality. Viral co-detection was frequent in patients with cancer and ARIs.     

Detection of new respiratory viruses in hospitalized infants with bronchiolitis: a three‐year prospective study

Aim: We have designed a study with the objective of describing the clinical impact of other viruses different from the respiratory syncytial virus (RSV) in hospitalized infants with bronchiolitis. Methods: A 3 year prospective study was conducted on infants admitted to the Paediatrics Department of the Severo Ochoa Hospital (Spain). We studied the frequency of 16 respiratory viruses. Clinical characteristics of RSV‐only infections were compared with other single agent viral infections. Results: Positive results were confirmed in 275 (86.5%) of the 318 children studied. A single virus was detected in 196 patients and 79 were dual or multiple viral infections. RSV was detected in 61.3% of total bronchiolitis. Rhinovirus (RV) was 17.4% of the identified virus, followed by human bocavirus (HBoV), adenovirus and metapneumovirus (hMPV). Only RV, HBoV and hMPV were significant as single infections. RSV patients were younger than HBoV (p > 0.0001) and hMPV (p = 0.025). Seasonality was clearly different between them. Children with RSV infection needed treatment in the intensive care unit more frequently than others. Conclusions: In hospitalized infants, RSV was the most frequent agent in bronchiolitis in winter, but other viruses were present in 47% of the patients. RV, HBoV and hMPV had a significant proportion of single infections. Clinical characteristics were similar amongst them, but seasonality was clearly different.     

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目的 了解儿童急性下呼吸道感染(ALRTI)病毒病原学特点.方法 2007年3月至2008年2月,在北京儿童医院内科就诊及住院治疗的临床诊断为ALRTI的患儿共572例.对每例患儿在就诊当日或次日采集鼻咽吸取物1份,采用逆转录(RT)-PCR方法进行常见呼吸道病毒核酸检测,包括呼吸道合胞病毒(RSV)、鼻病毒(RV)、副流感病毒(PIV)1～4型、甲型及乙型流感病毒(IFA、IFB)、腺病毒(AdV)、肠道病毒(EV)、冠状病毒(HCoV)、偏肺病毒(hMPV)及博卡病毒(HBoV).结果 572例患儿标本中,444例检出至少1种病毒,总检出率77.6%.各种病毒中,RSV检出率最高,占48.3%,其次是RV(27.1%)和PIV(13.3%).不同年龄组病毒的总检出率差异有统计学意义,<3岁组检出率较高,≥5岁组病毒检出率明显降低.不同年龄组JLRTI病原谱有所不同,<5岁各组主要是RSV、RV、PIV,而≥5岁组则主要为RV、IFV、RSV.572例中,158例(27.6%)检出2种或2种以上病毒,<1岁惠儿混合感染率最高,为40.2%,随年龄增长混合感染率逐渐下降,≥5岁患儿混合感染率仅为14.0%.结论 就诊于北京儿童医院的ALRTI患儿中,5岁以下者ALRTI的主要病毒病原是RSV、RV、PIV;≥5岁则主要为RV、IFV、RSV.     

2013~2018年重庆地区2 066例急性下呼吸道感染住院患儿呼吸道合胞病毒流行特征分析

目的 研究急性下呼吸道感染住院患儿呼吸道合胞病毒（RSV）检出率、流行规律及临床特征。方法 收集2013年6月至2018年5月于重庆医科大学附属儿童医院呼吸中心住院的2岁以下急性下呼吸道感染（ALRI）患儿鼻咽抽吸物,采用多重PCR检测16种常见呼吸道病毒,分析RSV流行特征。结果 共纳入2 066例ALRI住院患儿,病毒检出阳性1 595份（77.20%）。其中RSV阳性检出826份（39.98%）。RSV阳性样本中,RSV-A阳性410份（49.6%）,RSV-B阳性414份（50.1%）,RSV-A与RSV-B均阳性2份（0.2%）。2013~2014年、2016~2017年主导流行亚型为RSV-B,2014~2015年、2017~2018年以RSV-A为主要检出亚型,2015~2016年为RSV-A与RSV-B共同流行。冬季检出率最高。RSV合并人鼻病毒为最常见的2种病毒混合检出组合（123份）。该组患儿较单一RSV检出患儿更易出现喘息（P=0.030）。在2 066例患儿中,单一RSV检出298份,RSV混合其他病毒检出148份,其他病毒检出389份,病毒检出阴性241份。RSV单一检出组较其他病毒检出组和病毒检出阴性组月龄更小,更易发生呼吸困难、呼吸衰竭及重症下呼吸道感染（P < 0.0083）。RSV-A阳性患儿中的男性比例高于RSV-B阳性患儿（P=0.004）,而临床表现二者未见显著差异。结论 2013~2018年重庆地区RSV-A与RSV-B既可分别主导流行,也可共同流行;RSV为急性下呼吸道感染住院患儿最主要病毒病原,易导致重症下呼吸道感染;RSV-A和RSV-B感染患儿临床表现无差异,但RSV-A更易感染男性患儿。     

Clinical and laboratory features of pertussis in infants at the onset of a California epidemic

We report clinical characteristics and outcome of infants <3 months of age hospitalized with pertussis compared with viral respiratory infection (respiratory syncytial virus and influenza). Patients with pertussis more often were afebrile, had more visits before admission, and had longer hospital stays. Household coughing contacts were common.     

Pertussis is common in nonvaccinated infants hospitalized for respiratory syncytial virus infection

BACKGROUND: There is some evidence that Bordetella pertussis can cause co-infection with respiratory syncytial virus (RSV). SUBJECTS AND METHODS: RSV etiology was studied by antigen detection in 117 infants <6 months of age, who were hospitalized for respiratory tract infection during an RSV epidemic. B. pertussis etiology was studied by polymerase chain reaction in those 88 in whom parents or nurses reported cough. RESULTS: RSV was found in 91 (78%) infants and B. pertussis in 9 (8%) infants. In 7 cases, there was mixed RSV-pertussis infection. In retrospective analysis, RSV and mixed RSV-pertussis cases could not be separated by clinical characteristics. CONCLUSIONS: Co-infection caused by B. pertussis was present in 8% of infants, aged <6 months, who were hospitalized for RSV infection. To avoid under-diagnosis, pertussis should be considered in all nonvaccinated infants with lower respiratory tract infection.     

The impact of dual viral infection in infants admitted to a pediatric intensive care unit associated with severe bronchiolitis

INTRODUCTION: Bronchiolitis is a major cause of morbidity and mortality in early childhood worldwide. The presence of more than one pathogen may influence the natural history of acute bronchiolitis in infants. OBJECTIVE: To investigate the relevance of dual viral infection in infants with severe bronchiolitis hospitalized in a short-term unit compared with those in a pediatric intensive care unit (PICU). STUDY DESIGN: One hundred eighty infants <1 year old hospitalized with bronchiolitis in a short-term unit (n = 92) or admitted to the PICU (n = 88) during 2 consecutive winter seasons 2003/2004 and 2004/2005 were evaluated. Molecular biology and standard methods were used to diagnose human respiratory viruses in nasal/throat swabs and nasal aspirates. Clinical data related to host factors and viral prevalence were compared among infants requiring or not PICU support. RESULTS: A viral agent was identified in 96.1% of infants with bronchiolitis. Respiratory syncytial virus (70.6% and 73.6%, respectively in the short-term unit and PICU) and rhinovirus (18.5% and 25.3%, respectively in the short-term unit and PICU) were the main detected respiratory viruses in infants hospitalized in both units. No significant difference in viral prevalence was observed between the populations studied. From multivariate analysis, infants with coinfections were 2.7 times (95% CI: 1.2-6.2) more at risk for PICU admission than those with a single infection. Respiratory syncytial virus and rhinovirus were the viruses most frequently identified in mixed infections in infants hospitalized with bronchiolitis. CONCLUSIONS: Dual viral infection is a relevant risk factor for the admission of infants with severe bronchiolitis to the PICU.     

Association between multiple respiratory viral infections and pediatric intensive care unit admission among infants with bronchiolitis

BackgroundIt is unclear whether multiple respiratory viral infections are associated with more severe bronchiolitis requiring pediatric intensive care unit (PICU) admission. We aimed to identify the association between multiple respiratory viral infections and PICU admission among infants with bronchiolitis.MethodsWe performed a 1:1 case-control study enrolling previously healthy full-term infants (≤12 months) with bronchiolitis admitted to the PICU as cases and those to the general pediatric ward as controls from 2015 to 2017. Multiplex polymerase chain reaction (PCR) was used for detection of the respiratory viruses. We summarized the characteristics of infants admitted to the PICU and the general pediatric unit. Multivariable logistic regression analysis was used to fit the association between multiple respiratory viral infections (≥2 strains) and PICU admission.ResultsA total of 135 infants admitted to the PICU were compared with 135 randomly selected control infants admitted to the general pediatric unit. The PICU patients were younger (median: 2.2 months, interquartile range: 1.3–4.2) than the general ward patients (median: 3.2 months, interquartile range: 1.6–6.4). Respiratory syncytial virus (74.1%), rhinovirus (28.9%), and coronavirus (5.9%) were the most common viruses for bronchiolitis requiring PICU admission. Patients with bronchiolitis admitted to the PICU tended to have multiple viral infections compared with patients on the general ward (23.0% vs. 10.4%, P < 0.001). In the multivariable logistic regression analysis, bronchiolitis with multiple viral infections was associated with higher odds of PICU admission (adjusted odds ratio: 2.56, 95% confidence interval: 1.17–5.57, P = 0.02).ConclusionInfants with multiviral bronchiolitis have higher odds of PICU admission compared with those with a single or nondetectable viral infection.     

Equal virulence of rhinovirus and respiratory syncytial virus in infants hospitalized for lower respiratory tract infection

Respiratory syncytial virus (RSV) and rhinovirus (RV) are predominant viruses associated with lower respiratory tract infection in infants. We compared the symptoms of lower respiratory tract infection caused by RSV and RV in hospitalized infants. RV showed the same symptoms as RSV, so on clinical grounds, no difference can be made between these pathogens. No relation between polymerase chain reaction cycle threshold value and length of hospital stay was found.     

Etiology of acute lower respiratory tract infection

Objective : To identify pathogens responsible for acute severe lower respiratory tract infection (ALRTI) in under five children by non-invasive methods.Method : 95 children hospitalized with acute severe lower respiratory tract infection were investigated for identification of viruses, bacteria, chlamydia or mycoplasma by nasopharyngeal aspirates, blood culture and serology.Result : Etiological agents could be identified in 94% of the patients. Viruses from NP aspirate could be isolated in 36 (38%), bacterial isolates from blood cultures in 15(16%); mycoplasma was identified in 23(24%) and chlamydia in 10(11%) by serological tests; mixed infections were present in 8 (8%) patients.Conclusion : Noninvasive methods can be useful in identifying etiological agents in severe ALRTI     

Single versus dual respiratory virus infections in hospitalized infants: impact on clinical course of disease and interferon-gamma response

BACKGROUND: Dual respiratory viral infections are frequently associated with lower respiratory tract illness in infants. This study aimed to determine the impact of a dual respiratory viral infection on specific aspects of the infant's immune response and the clinical course of illness. METHODS: A prospective study was performed with 772 infants hospitalized from October 2000 through July 2004. Sensitive polymerase chain reaction methodology revealed the presence of a single respiratory virus in 443 (57%) of 772 cases, whereas dual infections were identified in 153 (20%) of cases. From 250 infants with confirmed respiratory viral infection, fresh heparinized blood was analyzed for interferon-gamma (IFN-gamma) responses by flow cytometry. Of these, 191 patients had a single infection with respiratory syncytial virus (RSV), rhinoviruses, adenoviruses or influenza viruses; and 59 patients had a dual infection with RSV and rhinoviruses, RSV and adenoviruses, influenza viruses and rhinoviruses or adenoviruses and rhinoviruses. The clinical features and peripheral lymphocyte IFN-gamma responses were compared among infants with single or dual infections. RESULTS: It was found that dual infections with non-RSV respiratory viruses induced peripheral blood mononuclear cell IFN-gamma responses that mimic those of single infections, whereas coinfection with RSV was associated with reduced IFN-gamma responses and a more severe clinical course of lower respiratory tract disease. CONCLUSIONS: The results indicate that the clinical characteristics and the IFN-gamma response differ significantly in single and dual respiratory viral infection, depending on the nature of the simultaneously detected viruses. In dual infections, RSV involvement was associated with a decreased IFN-gamma response in peripheral blood mononuclear cell and an increase in severity of illness.     

Neonatal nosocomial respiratory infection with coronavirus: a prospective study in a neonatal intensive care unit

The aim of this prospective study was to evaluate the incidence of viral respiratory infection in hospitalized premature newborn infants and to assess the role of coronaviruses. All hospitalized premature infants with a gestational age less than or equal to 32 weeks were included. Tracheal or nasopharyngal specimens were studied by immunofluorescence for coronaviruses, respiratory syncytial virus, adenoviruses, influenza and parainfluenza viruses. Forty premature infants were included; 13 samples were positive in 10 newborns (coronaviruses n = 10; influenza 1 n = 2; adenovirus n = 1). None was positive at admission. All premature infants infected with coronaviruses had symptoms of bradycardia, apnea, hypoxemia, fever or abdominal distension. Chest X-ray revealed diffuse infiltrates in two cases. However, no significant difference was observed between infected and non-infected premature infants for gestational age, birth weight, duration of ventilation, age at discharge, incidence of apnea or bradycardia. Nosocomial respiratory tract infection with coronaviruses appears to be frequent. The clinical consequences should be evaluated in a larger population.     

Human parainfluenza virus surveillance in pediatric patients with lower respiratory tract infections: a special view of parainfluenza type 4

Objective

Characterize the role of human parainfluenza virus and its clinical features in Brazilian children under 2 years of age presenting with acute lower respiratory tract infections.

Recurrent wheezing in preterm infants: Prevalence and risk factors

ObjectiveTo evaluate the prevalence and risk factors associated with progression to recurrent wheezing in preterm infants.MethodsThe cross-sectional study was carried out in 2014 and 2015 and analyzed preterm infants born between 2011 and 2012. The search for these children was performed in a university maternity hospital and a Special Immunobiological Reference Center. The evaluation was performed through a questionnaire applied during a telephone interview.ResultsThe study included 445 children aged 39 (18–54) months. In the univariate analysis, the risk factors with the greatest chance of recurrent wheezing were birth weight <1000 g, gestational age <28 weeks, living with two or more siblings, food allergy, and atopic dermatitis in the child, as well as food allergy and asthma in the parents. In the multivariate analysis, there was a significant association between recurrent wheezing and gestational age at birth <28 weeks, food allergy and atopic dermatitis in the child, and living with two or more children. Of the 445 analyzed subjects, 194 received passive immunization against the respiratory syncytial virus, and 251 preterm infants were not immunized. There was a difference between the gestational age of these subgroups (p < 0.001). The overall prevalence of recurrent wheezing was 27.4% (95% CI: 23.42–31.70), whereas in the children who received passive immunization it was 36.1% (95% CI: 29.55–43.03).ConclusionsPersonal history of atopy, lower gestational age, and living with two or more children had a significant association with recurrent wheezing. Children with lower gestational age who received passive immunization against the respiratory syncytial virus had a higher prevalence of recurrent wheezing than the group with higher gestational age.     

771例小儿下呼吸道感染的病毒病原检测分析

目的 通过检测和分析下呼吸道感染住院患儿的病毒病原学,掌握,小儿病毒感染的病原学特点.方法 对临床诊断为下呼吸道感染的771例住院患儿下呼吸道分泌物采用直接免疫荧光法进行常见的七种呼吸道病毒抗原检测.结果 771例患儿中共有243例病毒检测阳性,总阳性率占31.52%.呼吸道病毒感染与年龄和季节有明显的相关性.哮喘急性发作患儿病毒检出率最高(72.73%);其次为毛细支气管炎,病毒检出率达58.80%,主要病原为呼吸道合胞病毒;第三位是喘息性支气管炎患儿,病毒检出率为35.56%.结论 小儿在不同年龄、不同季节存在不同的病毒感染率.婴幼儿感染率明显高于其他年龄儿童.呼吸道合胞病毒、副流感病毒Ⅲ是小儿下呼吸道感染的主要病毒.病毒感染是喘息的主要原因.