Pneumonia in pediatric outpatients: cause and clinical manifestations

Antibiotic prescribing practices for acute respiratory illness in children less than 24 months of age in Kenema, Sierra Leone: is it time to move beyond algorithm driven decision making?

BACKGROUND

Lower respiratory tract infections are the leading cause of mortality in young children globally. In many resource-limited settings clinicians rely on guidelines such as IMCI or ETAT + that promote empiric antibiotic utilization for management of acute respiratory illness (ARI). Numerous evaluations of both guidelines have shown an overall positive response however, several challenges have also been reported, including the potential for over-prescribing of unnecessary antibiotics. The aims of this study were to describe the antibiotic prescribing practices for children less than 24 months of age with symptoms of ARI, that were admitted to Kenema Government Hospital (KGH) in the Eastern Province of Sierra Leone, and to identify the number of children empirically prescribed antibiotics who were admitted to hospital with ARI, as well as their clinical signs, symptoms, and outcomes.

METHODS

We conducted a prospective study of children < 24 months of age admitted to the KGH pediatric ward with respiratory symptoms between October 1, 2020 and May 31, 2022. Study nurses collected data on demographic information, medical and medication history, and information on clinical course while hospitalized.

RESULTS

A total of 777 children were enrolled. Prior to arrival at the hospital, 224 children (28.8%) reported taking an antibiotic for this illness without improvement. Only 15 (1.9%) children received a chest radiograph to aid in diagnosis and 100% of patients were placed on antibiotics during their hospital stay.

CONCLUSIONS

Despite the lives saved, reliance on clinical decision-support tools such as IMCI and ETAT + for pediatric ARI, is resulting in the likely over-prescribing of antibiotics. Greater uptake of implementation research is needed to develop strategies and tools designed to optimize antibiotic use for ARI in LMIC settings. Additionally, much greater priority needs to be given to ensuring clinicians have the basic tools for clinical diagnosis, as well as greater investments in essential laboratory and radiographic diagnostics that help LMIC clinicians move beyond the sole reliance on algorithm based clinical decision making.

Infant mortality rates and pneumococcal vaccines: a time-series trend analysis in 194 countries, 1950-2020

Pneumonia due to Streptococcus pneumoniae (pneumococcus) is a major cause of mortality in infants (children under 1 year of age), and pneumococcal conjugate vaccines (PCVs), delivered during the first year of life, are available since the year 2000. Given those two premises, the conclusion follows logically that favourable impact reported for PCVs in preventing pneumococcal disease should be reflected in the infant mortality rates (IMRs) from all causes. Using publicly available datasets, country-level IMR estimates from UNICEF and PCV introduction status from WHO, country-specific time series analysed the temporal relationship between annual IMRs and the introduction of PCVs, providing a unique context into the long-term secular trends of IMRs in countries that included and countries that did not include PCVs in their national immunisation programmes. PCV status was available for 194 countries during the period 1950-2020: 150 (77.3%) of these countries achieved nationwide PCV coverage at some point after the year 2000, 13 (6.7%) achieved only partial or temporary PCV coverage, and 31 (15.9%) never introduced PCVs to their population. One hundred and thirty-nine (92.7%) of countries that reported a decreasing (negative) trend in IMR, also reported a strong correlation with decreasing maternal mortality rates (MMRs), suggesting an improvement in overall child/mother healthcare. Conversely, all but one of the countries that never introduced PCVs in their national immunisation programme also reported a decreasing trend in IMR that strongly correlates with MMRs. IMRs have been decreasing for decades all over the world, but this latest decrease may not be related to PCVs.

Lectin Microarray Combined with Mass Spectrometry Identifies Haptoglobin-Related Protein (HPR) as a Potential Serologic Biomarker for Separating Nonbacterial Pneumonia from Bacterial Pneumonia in Childhood

PURPOSE

Etiological diagnosis of pediatric patients with community-acquired pneumonia is difficult. For therapy, one of the major problems is the difficulty in separating bacterial pneumonia which would benefit from antibiotics from nonbacterial pneumonia. Therefore, to identify potential biomarkers for distinguishing nonbacterial pneumonia from bacterial pneumonia are sought .

EXPERIMENTAL DESIGN

Lectin microarray containing 91 lectins is used to screen serums from pediatric patients with pneumonia. Lectin-based pull-down assay combined with LC-MS/MS is used to identify the potential biomarkers.

RESULTS

SNA-I, a lectin binding preferentially to α2-6 linked sialic acid residues, shows higher binding signals (near 42 kDa) in the mycoplasma pneumonia group, when compared with the other groups. A total of 18 proteins are identified with LC-MS/MS. By western blot analysis, the authors confirm that the expression of haptoglobin-related protein (HPR) is elevated in pediatric patients with pneumonia compared with normal children (p < 0.001). Furthermore, HPR is higher in the mycoplasma pneumonia group (p < 0.01) and the viral pneumonia group (p < 0.05), when compared with the bacterial pneumonia group.

CONCLUSIONS AND CLINICAL RELEVANCE

These results indicate that HPR is a potential serologic biomarker which can differentiate between bacterial pneumonia and nonbacterial pneumonia. Detection of serum HPR might be useful for clinical diagnosis.

Association of C-Reactive Protein With Bacterial and Respiratory Syncytial Virus-Associated Pneumonia Among Children Aged <5 Years in the PERCH Study

Background.

Lack of a gold standard for identifying bacterial and viral etiologies of pneumonia has limited evaluation of C-reactive protein (CRP) for identifying bacterial pneumonia. We evaluated the sensitivity and specificity of CRP for identifying bacterial vs respiratory syncytial virus (RSV) pneumonia in the Pneumonia Etiology Research for Child Health (PERCH) multicenter case-control study.

Methods.

We measured serum CRP levels in cases with World Health Organization-defined severe or very severe pneumonia and a subset of community controls. We evaluated the sensitivity and specificity of elevated CRP for "confirmed" bacterial pneumonia (positive blood culture or positive lung aspirate or pleural fluid culture or polymerase chain reaction [PCR]) compared to "RSV pneumonia" (nasopharyngeal/oropharyngeal or induced sputum PCR-positive without confirmed/suspected bacterial pneumonia). Receiver operating characteristic (ROC) curves were constructed to assess the performance of elevated CRP in distinguishing these cases.

Results.

Among 601 human immunodeficiency virus (HIV)-negative tested controls, 3% had CRP ≥40 mg/L. Among 119 HIV-negative cases with confirmed bacterial pneumonia, 77% had CRP ≥40 mg/L compared with 17% of 556 RSV pneumonia cases. The ROC analysis produced an area under the curve of 0.87, indicating very good discrimination; a cut-point of 37.1 mg/L best discriminated confirmed bacterial pneumonia (sensitivity 77%) from RSV pneumonia (specificity 82%). CRP ≥100 mg/L substantially improved specificity over CRP ≥40 mg/L, though at a loss to sensitivity.

Conclusions.

Elevated CRP was positively associated with confirmed bacterial pneumonia and negatively associated with RSV pneumonia in PERCH. CRP may be useful for distinguishing bacterial from RSV-associated pneumonia, although its role in discriminating against other respiratory viral-associated pneumonia needs further study.

Etiologic spectrum and occurrence of coinfections in children hospitalized with community-acquired pneumonia

Background

Co-infections are common in childhood community acquired pneumonia (CAP). However, their etiological pattern and clinical impact remains inconclusive.

Methods

Eight hundred forty-six consecutive children with CAP were evaluated prospectively for the presence of viral and bacterial pathogens. Nasopharyngeal aspirates were examined by direct immunofluorescence assay or polymerase chain reaction (PCR) for viruses. PCR of nasopharyngeal aspirates and enzyme-linked immunosorbent assays were performed to detect M. pneumoniae. Bacteria was detected in blood, bronchoalveolar lavage specimen, or pleural fluid by culture.

Results

Causative pathogen was identified in 70.1% (593 of 846) of the patients. The most commonly detected pathogens were respiratory syncytial virus (RSV) (22.9%), human rhinovirus (HRV) (22.1%), M. pneumoniae (15.8%). Coinfection was identified in 34.6% (293 of 846) of the patients. The majority of these (209 [71.3%] of 293) were mixed viral-bacterial infections. Age < 6 months (odds ratio: 2.1; 95% confidence interval: 1.2–3.3) and admission of PICU (odds ratio: 12.5; 95% confidence interval: 1.6–97.4) were associated with mix infection. Patients with mix infection had a higher rate of PICU admission.

Conclusions

The high mix infection burden in childhood CAP underscores a need for the enhancement of sensitive, inexpensive, and rapid diagnostics to accurately identify pneumonia pathogens.

Biomarkers in Pediatric Community-Acquired Pneumonia

Community-acquired pneumonia (CAP) is an infectious disease caused by bacteria, viruses, or a combination of these infectious agents. The severity of the clinical manifestations of CAP varies significantly. Consequently, both the differentiation of viral from bacterial CAP cases and the accurate assessment and prediction of disease severity are critical for effectively managing individuals with CAP. To solve questionable cases, several biomarkers indicating the etiology and severity of CAP have been studied. Unfortunately, only a few studies have examined the roles of these biomarkers in pediatric practice. The main aim of this paper is to detail current knowledge regarding the use of biomarkers to diagnose and treat CAP in children, analyzing the most recently published relevant studies. Despite several attempts, the etiologic diagnosis of pediatric CAP and the estimation of the potential outcome remain unsolved problems in most cases. Among traditional biomarkers, procalcitonin (PCT) appears to be the most effective for both selecting bacterial cases and evaluating the severity. However, a precise cut-off separating bacterial from viral and mild from severe cases has not been defined. The three-host protein assay based on C-reactive protein (CRP), tumor necrosis factor-related apoptosis-inducing ligand (TRAIL), plasma interferon-γ protein-10 (IP-10), and micro-array-based whole genome expression arrays might offer more advantages in comparison with former biomarkers. However, further studies are needed before the routine use of those presently in development can be recommended.

Human rhinoviruses and severe respiratory infections: is it possible to identify at-risk patients early?

Molecular methods of viral screening have demonstrated that human rhinoviruses (HRVs) are associated with lower respiratory tract infections (LRTIs, including bronchiolitis and pneumonia), exacerbations of chronic pulmonary disease and the development of asthma. Patients with severe chronic diseases are at greater risk of developing major clinical problems when infected by HRVs, particularly if they are immunocompromised or have a chronic lung disease. Analysing the characteristics of HRVs does not provide any certainty concerning the risk of a poor prognosis and, although viremia seems to be associated with an increased risk of severe HRV infection, the available data are too scanty to be considered conclusive. However, a chest x-ray showing alveolar involvement suggests the potentially negative evolution of a bacterial superinfection. There is therefore an urgent need for more effective diagnostic, preventive and therapeutic measures in order to prevent HRV infection, and identify and treat the patients at highest risk.

Variability and accuracy in interpretation of consolidation on chest radiography for diagnosing pneumonia in children under 5 years of age

BACKGROUND

Consolidation on chest radiography is widely used as the reference standard for defining pneumonia and variability in interpretation is well known but not well explored or explained.

METHODS

Three pediatric sub-specialists (infectious diseases, radiology and respiratory medicine) viewed 3,033 chest radiographs in children aged under 5 years of age who presented to one Emergency Department (ED) with a febrile illness. Radiographs were viewed blind to clinical information about the child and blind to findings of other readers. Each chest radiograph was identified as positive or negative for consolidation. Percentage agreement and kappa scores were calculated for pairs of readers. Prevalence of consolidation and reader sensitivity/specificity was estimated using latent class analysis.

RESULTS

Using the majority rule, 456 (15%) chest radiographs were positive for consolidation while the latent class estimate was 17%. The radiologist was most likely (21.3%) and respiratory physician least likely (13.7%) to diagnose consolidation. Overall percentage agreement for pairs of readers was 85-90%. However, chance corrected agreement between the readers was moderate, with kappa scores 0.4-0.6 and did not vary with patient characteristics (age, gender, and presence of chronic illness). Estimated sensitivity ranged from 0.71 to 0.81 across readers, and specificity 0.91 to 0.98.

CONCLUSIONS

Overall agreement for identification of consolidation on chest radiographs was good, but agreement adjusted for chance was only moderate and did not vary with patient characteristics. Clinicians need to be aware that chest radiography is an imperfect test for diagnosing pneumonia and has considerable variability in its interpretation.

Phylogenetic analysis of human rhinovirus isolates collected from otherwise healthy children with community-acquired pneumonia during five successive years

In order to evaluate the circulation of the different human rhinovirus (HRV) species and genotypes in Italian children with radiographically confirmed community-acquired pneumonia (CAP), a nasopharyngeal swab was obtained from 643 children admitted to hospital because of CAP during five consecutive winter and early spring seasons (2007-2012). Real-time reverse transcriptase polymerase chain reaction (RT-PCR) was used to identify HRV, and the HRV-positive samples were used for sequencing analysis and to reconstruct the phylogenetic tree. HRV was identified in 198 samples (42.2%), and the VP4/VP2 region was successfully amplified in 151 (76.3%). HRV-A was identified in 78 samples (51.6%), HRV-B in 14 (9.3%) and HRV-C in 59 (39.1%). Forty-seven (31.1%) of the children with HRV infection were aged <1 year, 71 (47.0%) were aged 1-3 years, and 33 (21.9%) were aged ≥4 years. Blast and phylogenetic analyses showed that the HRV strains were closely related to a total of 66 reference genotypes, corresponding to 29 HRV-A, 9 HRV-B and 28 HRV-C strains. Nucleotide variability was 37% between HRV-A and HRV-B, 37.3% between HRV-A and HRV-C, and 39.9% between HRV-B and HRV-C. A number of sequences clustered with known serotypes and, within these clusters, there were strains circulating during several seasons. The most frequently detected genotypes were HRV-A78 (n=17), HRV-A12 (n=9) and HRV-C2 (n=5). This study shows that, although it is mainly associated with HRV-A, pediatric CAP can also be diagnosed in subjects infected by HRV-C and, more rarely, by HRV-B. Moreover, a large number of genotypes may be involved in causing pediatric CAP and can be different from year to year. Although the prolonged circulation of the same genotypes can sometimes be associated with a number of CAP episodes in different years.

Impact of rhinovirus nasopharyngeal viral load and viremia on severity of respiratory infections in children

There are few and partially discordant data regarding nasopharyngeal rhinovirus (RV) load and viremia, and none of the published studies evaluated the two variables together. The aim of this study was to provide new information concerning the clinical relevance of determining nasopharyngeal viral load and viremia when characterising RV infection. Nasopharyngeal swabs were obtained from 251 children upon their admission to hospital because of fever and signs and symptoms of acute respiratory infection in order to identify the virus and determine its nasopharyngeal load, and a venous blood sample was taken in order to evaluate viremia. Fifty children (19.9 %) had RV-positive nasopharyngeal swabs, six (12 %) of whom also had RV viremia: RV-C in four cases (66.6 %), and RV-A and RV-B in one case each. The RV nasopharyngeal load was significantly higher in the children with RV viremia (p < 0.001), who also had a higher respiratory rate (p = 0.02), white blood cell counts (p = 0.008) and C-reactive protein levels (p = 0.006), lower blood O2 saturation levels (P = 0.005), and more often required O2 therapy (p = 0.009). The presence of RV viremia is associated with a significantly higher nasopharyngeal viral load and more severe disease, which suggests that a high nasopharyngeal viral load is a prerequisite for viremia, and that viremia is associated with considerable clinical involvement.

Circulation of different rhinovirus groups among children with lower respiratory tract infection in Kiremba, Burundi

The purpose of this investigation was to collect information regarding rhinovirus (RV) circulation in children with lower respiratory tract infections (LRTIs) in Burundi, Central Africa. We enrolled all of the children aged between 1 month and 14 years who were admitted to the hospital of Kiremba, North Burundi, with fever and signs and symptoms of LRTI (i.e., cough, tachypnea, dyspnea or respiratory distress, and breathing with grunting or wheezing sounds with rales) between 1 November 2010 and 31 October 2011, and obtained nasopharyngeal swabs for RV detection by means of polymerase chain reaction (PCR). The VP4/VP2 region of the positive samples was sequenced to determine the species of RV (A, B, or C). Four hundred and sixty-two children were enrolled: 160 (34.6 %) with bronchitis, 35 (7.6 %) with infectious wheezing, and 267 (57.8 %) with community-acquired pneumonia (CAP). RV infection was demonstrated in 186 patients [40.3 %; mean age ± standard deviation (SD) 1.77 ± 2.14 years]. RV infection was detected in 78 patients aged <12 months (40.0 %), 102 aged 12-48 months (44.3 %), and six aged >48 months (16.7 %; p < 0.01 vs. the other age groups). The most frequently identified RV was RV-A (81 cases, 43.5 %), followed by RV-C (47, 25.3 %) and RV-B (18, 9.7 %); subtyping was not possible in 40 cases (21.5 %). RV-A was significantly associated with bronchitis and CAP (p < 0.01) and RV-C with wheezing (p < 0.05). In Burundi, RVs are frequently detected in children with LRTIs. RV-A seems to be the most important species and is identified mainly in patients with bronchitis and CAP.

Impact of rhinoviruses on pediatric community-acquired pneumonia

This study of 592 children seen in our Emergency Department with radiographically confirmed community-acquired pneumonia (CAP) was designed to evaluate the role of rhinoviruses (RVs) in the disease. The respiratory secretions of each child were assayed using RVP Fast in order to detect 17 respiratory viruses, and the RV-positive samples were characterised by means of real-time polymerase chain reaction and sequencing. RVs were identified in 172 cases (29.0%): 48/132 children aged <1 year (36.3%), 80/293 aged 1–3 years (27.3%), and 44/167 aged ≥4 years (26.3%). Sequencing demonstrated that 82 RVs (49.1%) were group A, 17 (10.1%) group B, and 52 (31.1%) group C; 21 (12.2%) were untyped. RVs were found as single agents in 99 cases, and together with two or more other viruses in 73 (40.7%). There were only marginal differences between the different RV groups and between single RV infection and RV co-infections. RV CAP is frequent not only in younger but also in older children, and RV-A is the most common strain associated with it. The clinical relevance of RV CAP seems to be mild to moderate without any major differences between the A and B strains and the recently identified RV C.

Bronconeumopatías agudas del niño

Las infecciones infantiles afectan con frecuencia al aparato respiratorio inferior. Las clasificaciones convencionales, basadas en el tipo de afección anatómica, radiológica y etiopatogénica, permiten definir entidades clínicas (bronquitis, bronquiolitis, neumopatía); sin embargo, la evaluación de la gravedad del proceso es lo más útil para decidir el tipo y la rapidez del tratamiento. Aunque la etiología viral es la más frecuente, la estrategia fundamental para reducir la morbilidad e incluso la mortalidad de las infecciones respiratorias bajas se basa en el tratamiento adecuado de las neumonías bacterianas. Ante la ausencia de especificidad, es indispensable, cuando esté indicado, recurrir a una antibioticoterapia inicial probabilística que incluya el neumococo. En el niño, las muestras no suelen proceder del parénquima pulmonar y, además, la recogida de las secreciones bronquiales durante los primeros años de vida no es de buena calidad. Al contrario de lo que ocurre con los virus, el examen bacteriológico de las secreciones de las vías respiratorias altas es poco útil, porque los niños suelen ser portadores de gérmenes que pueden causar neumopatías. Los datos clínicos y radiológicos sólo pueden sugerir el diagnóstico. El desarrollo de técnicas que detectan antígenos microbianos o la búsqueda de material genético por biología molecular han permitido mejorar de manera significativa la identificación del patógeno responsable y la elección del tratamiento adecuado. Algunos grupos particulares de pacientes pueden padecer una afección respiratoria por agentes infecciosos inusuales o, incluso, oportunistas. Una proporción importante de la afectación respiratoria del adulto puede atribuirse a las agresiones pulmonares sufridas durante su infancia. La aplicación de vacunas, en especial, la antigripal y la antineumocócica, es fundamental para la prevención de estas afecciones respiratorias.

Epidemiological and economic burden of pneumococcal diseases in Canadian children

BACKGROUND

With the arrival of a new conjugate pneumococcal vaccine, it is important to estimate the burden of pneumococcal diseases in Canadian children. The epidemiological data and the economic cost of these diseases are crucial elements in evaluating the relevance of a vaccination program.

METHODS

Using provincial databases, ad hoc surveys and published data, age-specific incidence rates of pneumococcal infections were estimated in a cohort of 340,000 children between six months and nine years of age. The costs of these diseases to the health system and to families were also evaluated using data from Quebec and Manitoba.

RESULTS

Cumulative risks were one in 5000 for pneumococcal meningitis, one in 500 for bacteremia and one in 20 for pneumonia, leading to 16 deaths in the cohort. About 262,000 otitis media episodes and 32,000 cases of myringotomy with ventilation tube insertion were attributable to Streptococcus pneumoniae. Societal costs were estimated at $125 million, of which 32% was borne by the health system and 68% was borne by families. Invasive infections represented only 2% of total costs, while 84% were generated by otitis media.

CONCLUSION

Pneumococcal infections represent a significant burden for Canadian children and society that could be significantly reduced through immunization.

Variations in the management of pneumonia in pediatric emergency departments: compliance with the guidelines

OBJECTIVE

We sought to assess compliance with evidence-based guidelines for the management of pediatric pneumonia, including the variations in tests ordered and antimicrobials prescribed. Our primary hypothesis was that compliance with the treatment recommendations from the most current guidelines would be low for antimicrobial prescriptions.

METHODS

We conducted a chart review at the Children's Hospital in London, Ont., to assess variation in the management of pediatric pneumonia. All patients aged 3 months to 18 years seen at the pediatric emergency department between Apr. 1, 2006, and Mar. 31, 2007, with a diagnosis of pneumonia were eligible for inclusion in the study.

RESULTS

Compliance with management guidelines was 59.7% (95% confidence interval [CI] 53%-66%, n = 211) in children 5-18 years old and 83.0% (95% CI 80%-86%, n = 605) in children 3 months to 5 years old. Significant variation existed in the choice of antimicrobial agent for children with pneumonia, with nonrecommended agents frequently prescribed.

CONCLUSION

Significant variation existed in the management of pediatric pneumonia, and adherence to guidelines was low for the group of patients aged 5-18 years. Future studies should attempt to provide guidance to distinguish between viral and bacterial etiology to allow judicious use of antimicrobials.

Validation and development of a clinical prediction rule in clinically suspected community-acquired pneumonia

OBJECTIVES

To develop a mathematical model to predict the probability of having community-acquired pneumonia and to evaluate an already developed prediction rule that has not been validated in a clinical scenario.

METHODS

Children who presented with fever and had presumptive clinical diagnosis of pneumonia were evaluated in 4 institutions of different complexity during 1 year. The variables assessed were sex, age, respiratory rate, days with fever, maximum body temperature, presence of tachypnea, cough, chest pain, intercostal retraction, nasal flaring, abdominal pain, vomiting, grunting, rales, decreased breath sounds, wheezing, fatigue, loss of appetite, loss of sleep, and season of the year. The chest radiographs were photographed and then interpreted by 2 pediatric radiologists.

RESULTS

A total of 257 children were evaluated: 179 (69%) had clinical and radiological diagnosis of community-acquired pneumonia, and 78 (30%) had no radiological confirmation. A total of 96 photographs were recorded, and in 64 of the cases, there was agreement in the diagnosis between the evaluating pediatrician and the radiologists (kappa index = 0.68).With the calculated probabilities, it was possible to build a receiving operating characteristic curve and, based on the estimated coefficients we calculated, a value associated to the probability of having pneumonia.

CONCLUSIONS

We developed a model including 5 variables of high level of sensitivity for the diagnosis of pneumonia. To use it, it would be useful to apply the appropriate software. In addition, we validated a clinical prediction rule of 4 variables that proved to have 93.8% sensitivity to diagnose pneumonia in children with a fever and localized rales, or decreased breath sounds, or tachypnea, or any combination of these 4 variables.

Imaging of Chest Infections in Children

■ Imaging studies have limited value in the differentiation between viral and bacterial lower respiratory tract infections (moderate evidence).

■ CT provides more information than plain radiographs for complicated pulmonary infections with empyema, pleural effusion, or bronchopleural fistula (moderate evidence).

■ In immunocompromised patients, CT has been shown to characterize the type of infection better than plain radiographs (moderate evidence).

■ Ultrasound has an advantage over CT in the identification and characterization of complicated effusions (moderate evidence).

■ Early detection and therefore intervention for pleural complications of pneumonia are critical and can result in better outcomes (moderate evidence).

■ Early surgery (VATS) is more cost-effective than thoracotomy (without or with image guidance) in the treatment of empyemas in children (strong evidence).

Azithromycin does not improve disease course in hospitalized infants with respiratory syncytial virus (RSV) lower respiratory tract disease: a randomized equivalence trial

BACKGROUND

Nearly half of all hospitalized infants with respiratory syncytial virus (RSV) lower respiratory tract disease (LRTD) are treated with (parenteral) antibiotics. The present study was designed to test our hypothesis that the use of antibiotics would not lead to a reduced duration of hospitalization in mild to moderate RSV LRTD.

METHODS

Seventy-one patients < or =24 months of age with a virologically confirmed clinical diagnosis of RSV LRTD were randomized to azithromycin 10 mg/kg/day (n = 32) or placebo (n = 39) in a multicenter, randomized, double-blind, placebo-controlled equivalence trial during three RSV seasons (2002-2004 through 2005-2006). Primary endpoint was duration of hospitalization, secondary endpoints included duration of oxygen supplementation and nasogastric tube feeding, course of RSV symptom score, number of PICU referrals and number of patients who received additional antibiotic treatment. Data were analyzed according to the intention-to-treat principle using the Mann-Whitney U-test or chi2 test considering P < 0.05 as statistically significant.

RESULTS

Included patients were comparable with respect to baseline demographics, clinical characteristics, laboratory and roentgenologic investigations. The mean duration of hospitalization was not significantly different between patients treated with azithromycin or placebo (132.0 +/- 10.8 vs. 139.6 +/- 7.7 hr, P = 0.328). Azithromycin was not associated with a stronger resolution of clinical symptoms represented by the RSV symptom score. Four patients were treated with antibiotics after 72 hr, three of them were assigned to placebo (P = 0.406).

CONCLUSIONS

Infants and young children with RSV LRTD do not benefit from routine treatment with antibiotics (ISRCTN number 86554663).

Respiratory picornavirus infections in Korean children with lower respiratory tract infections

Recently, human rhinoviruses (RVs) and enteroviruses have been suggested as important etiological agents in young children with lower respiratory tract infections (LRTIs). We investigated the role of respiratory picornaviruses in hospitalized children with LRTI. A total of 233 nasopharyngeal samples were collected from hospitalized children with LRTIs from July 2004 to January 2006. All specimens were tested for the presence of human respiratory syncytial virus (hRSV), influenza virus A, influenza B, parainfluenzavirus, and adenovirus using direct immunofluorescent assay, and for human metapneumovirus (HMPV) by RT-PCR. Detection of RV was performed in nasopharyngeal samples by a RT-PCR assay that incorporated a BglI restriction enzyme digestion of the picornavirus RT-PCR amplicon, and detection of enterovirus was accomplished by hemi-nested RT-PCR using specific primers. Viral agents were detected in 70.4% (164/233) of the study population. The most frequently detected viruses were RV (64/233, 27.4%), hRSV (48/233, 20.6%), and enterovirus (43/233, 18.4%). Picornaviruses were detected as the sole viral agents in 27.0% (63/233) of children, whereas mixed viral infection was detected in 12.0%. These results suggest that picronavirus infection is an important etiological cause of LRTIs in Korean children.

Evaluation of the utility of radiography in acute bronchiolitis

OBJECTIVES

To determine the proportion of radiographs inconsistent with bronchiolitis in children with typical presentation of bronchiolitis and to compare rates of intended antibiotic therapy before radiography versus those given antibiotics after radiography.

STUDY DESIGN

We conducted a prospective cohort study in a pediatric emergency department of 265 infants aged 2 to 23 months with radiographs showing either airway disease only (simple bronchiolitis), airway and airspace disease (complex bronchiolitis), and inconsistent diagnoses (eg, lobar consolidation).

RESULTS

The rate of inconsistent radiographs was 2 of 265 cases (0.75%; 95% CI 0-1.8). A total of 246 children (92.8%) had simple radiographs, and 17 radiographs (6.9%) were complex. To identify 1 inconsistent and 1 complex radiograph requires imaging 133 and 15 children, respectively. Of 148 infants with oxygen saturation >92% and a respiratory disease assessment score <10 of 17 points, 143 (96.6%) had a simple radiograph, compared with 102 of 117 infants (87.2%) with higher scores or lower saturation (odds ratio, 3.9; 95% CI, 1.3-14.3). Seven infants (2.6%) were identified for antibiotics pre-radiography; 39 infants (14.7%) received antibiotics post-radiography (95% CI, 8-16).

CONCLUSIONS

Infants with typical bronchiolitis do not need imaging because it is almost always consistent with bronchiolitis. Risk of airspace disease appears particularly low in children with saturation higher than 92% and mild to moderate distress.

Aetiological agents, interleukin-6, interleukin-8 and CRP concentrations in children with community- and hospital-acquired pneumonia

OBJECTIVE

To determine the pathogens causing pneumonia in community-acquired pneumonia (CAP) and hospital-acquired pneumonia (HAP) and to investigate serum levels of interleukin-6 (IL-6), interleukin-8 (IL-8) and CRP in pneumonia caused by different aetiological agents.

STUDY DESIGN

Eighty-seven children (mostly < 5 years of age) were recruited in a prospective study, 55 of them with CAP without prior antibiotic treatment and 32 with HAP. Thirty healthy outpatient children served as controls.

RESULTS

The causative micro-organisms were determined by serological and microbiological methods in 40 cases with CAP (72.7%) and 30 with HAP (93.7%). In CAP, M. pneumoniae was the most common causative agent (43.6%), followed by S. pneumoniae (20%) and C. pneumoniae (18.1%). Bacteria alone were the sole causative agents in only 21.8% of cases with HAP. Pseudomonas aeruginosa (34.3%) and K. pneumoniae (32.5%) were the most frequently isolated. Although IL-6 and IL-8 levels were raised, there was no statistical difference between the CAP and HAP groups, or between bacterial and mycoplasma infections; neither was there a difference in CRP levels between these two groups.

CONCLUSION

The causes of pneumonia differ between CAP and HAP. Levels of IL-6, IL-8 and CRP are raised in pneumonia but are unhelpful in differentiating the various aetiologies.

Viral pneumonia in children

Viral pneumonia causes a heavy burden on our society. In the United States, more than one million cases of pneumonias afflict children under the age of 5 years, costing hundreds of millions of dollars annually. The majority of these infections are caused by a handful of common viruses. Knowledge of the epidemiology of these viruses combined with new rapid diagnostic techniques will provide faster and more, reliable diagnoses in the future. Although the basic clinical epidemiology of these viruses has been carefully investigated over the last 30 years, new molecular techniques are greatly expanding our understanding of these agents and the diseases they cause. Antigenic and genetic variations are being discovered in many viruses previously thought to be homogeneous. The exact roles and the biological significance of these variations are just beginning to be explored, but already evidence of differences in pathogenicity and immunogenicity has been found in many of these substrains. All of this information clearly will impact the development of future vaccines and antiviral drugs. Effective drugs exist for prophylaxis against influenza A and respiratory syncytial virus, and specific therapy exists for influenza A. Ribarivin is approved for use in respiratory synctial virus infections, and it alone or in combination with other agents (eg, IGIV) may be effective in immunocompromised patients, either in preventing the development of pneumonia or in decreasing morbidity and mortality. Many new antiviral agents are being tested and developed, and several are in clinical trials.

The burden of pneumonia in children in the developed world

There are few comprehensive epidemiological studies of pneumonia in the developed world. Ascertainment and definition are important variables in the estimation of pneumonia incidence both in primary care and from hospital data. The available figures suggest a burden of disease in the order of 10-15 cases/1000 children per year and a hospital admission rate of 1-4/1000 per year. Both incidence and hospital admission are greatest in the youngest children and rapidly fall after the age of 5 years. In a majority of cases of community acquired pneumonia an organism is not identified. Viral infections are common and influenza A, B, respiratory syncitial virus (RSV) and parainfluenza 1, 2 and 3 are the most common viruses identified. Streptococcus pneumoniae is the most common bacterial cause. Broad brush calculations suggest that the NHS cost of childhood pneumonia in England is 6-8 million pound sterling per annum. This does not include family and social costs. There is potential for new vaccine strategies to decrease childhood pneumonia.

Imaging in immunocompetent children who have pneumonia

This article discusses the common clinical scenarios regarding otherwise healthy children who develop suspected pneumonia in which imaging becomes an issue. The following topics are covered concerning the roles of imaging in the management of pneumonia: evaluation for possible pneumonia, determination of a specific etiologic agent, exclusion of other pathology, evaluation of the child with failure of pneumonia to clear, and evaluation of complications related to pneumonia.

Can chest X-ray predict pneumonia severity?

Predictors of the severity of pneumonia have not been thoroughly evaluated among children in developed countries. We investigate whether chest radiographic findings could be used as predictors of severity of childhood pneumonia. The study included 167 children, aged more than 12 months, hospitalized in our department during a 4-year period with unilateral lobar or segmental pneumonia. The durations of fever and of hospitalization were considered indicators of severity of the disease. The size of the consolidation and its location in the left hemithorax were independently associated with severity of the disease. Univariate analysis showed that the mean duration of fever and of hospitalization as well as the prevalence of pleural effusion was significantly higher among children with left-sided pneumonia. A multiple logistic regression analysis revealed that only the presence of pleural effusion was significantly more likely in left-sided pneumonia (odds ratio, 2.65; 95% confidence interval, 1.09-6.47; P = 0.031). We conclude that the size of consolidation and the side of its location can be used as predictors of severity of pneumonia, with left-sided pneumonia running a more severe course, possibly due to increased risk for the development of pleurisy.

Assessment and management of children aged 1-59 months presenting with wheeze, fast breathing, and/or lower chest indrawing; results of a multicentre descriptive study in Pakistan

BACKGROUND AND AIMS

Using current WHO guidelines, children with wheezing are being over prescribed antibiotics and bronchodilators are underutilised. To improve the WHO case management guidelines, more data is needed about the clinical outcome in children with wheezing/pneumonia overlap.

METHODOLOGY

In a multicentre prospective study, children aged 1-59 months with auscultatory/audible wheeze and fast breathing and/or lower chest indrawing were screened. Response to up to three cycles of inhaled salbutamol was recorded. The responders were enrolled and sent home on inhaled bronchodilators, and followed up on days 3 and 5.

RESULTS

A total of 1622 children with wheeze were screened from May 2001 to April 2002, of which 1004 (61.8%) had WHO defined non-severe and 618 (38.2%) severe pneumonia. Wheeze was audible in only 595 (36.7%) of children. Of 1004 non-severe pneumonia children, 621 (61.8%) responded to up to three cycles of bronchodilator. Of 618 severe pneumonia children, only 166 (26.8%) responded. Among responders, 93 (14.9%) in the non-severe and 63 (37.9%) children in the severe pneumonia group showed subsequent deterioration on follow ups. No family history of wheeze, temperature >100 degrees F, and lower chest indrawing were identified as predictors of subsequent deterioration.

CONCLUSIONS

Two third of children with wheeze are not identified by current WHO ARI (acute respiratory infections) guidelines. Antibiotics are over prescribed and bronchodilators under utilised in children with wheeze. Children with wheeze constitute a special ARI group requiring a separate management algorithm. In countries where wheeze is common it would be worthwhile to train health workers in use of the stethoscope to identify wheeze.

Procalcitonin as an early marker of infection in neonates and children

A child or neonate presenting with fever is a common medical problem. To differentiate between those with a severe bacterial infection and those with a localised bacterial or a viral infection can be a challenge. This review provides an overview of neonatal and paediatric studies that assess the use of procalcitonin as an early marker of bacterial infection. Procalcitonin is an excellent marker for severe, invasive bacterial infection in children. However, the use of procalcitonin in the diagnosis of neonatal bacterial infection is complicated, but if correctly used procalcitonin results in a higher specificity than C-reactive protein. In addition, procalcitonin has been shown to correlate with severity of disease (urinary tract infections and sepsis), and can therefore be used as a prognostic marker. Procalcitonin is therefore a useful additional tool for the diagnosis of bacterial disease in neonates and children.

Is routine chest radiography necessary for the initial evaluation of fever in neutropenic children with cancer?

BACKGROUND

The yield of routine chest radiography (CXR) as part of the initial management of febrile neutropenic pediatric oncology patients is questionable.

PROCEDURE

We retrospectively analyzed the clinical records of neutropenic (absolute neutrophil count < or = 0.5 x 10(9)/L) children with cancer, admitted with oral temperature > or = 38 degrees C to our institution, between January 2001 and October 2002. Following admission, patients received tobramycin plus (piperacillin or ticarcillin-clavulanic acid). Admission routine CXRs were reviewed. Clinical and radiological features were compared with the discharge diagnosis. Age, underlying disease, and the presence of pulmonary symptoms or signs were studied as possible predictors of CXR findings related to pneumonia.

RESULTS

In total, 88 patients experienced 170 episodes of fever. A routine admission CXR was obtained for 157 of the episodes. Radiologists found 20 (12.7%) abnormal CXR (6 with a segmental or lobar consolidation considered as a pneumonia). In addition, two patients with abnormal admission CXR developed lobar consolidation on a repeat film, later in their hospital course. There were no differences in age and type of underlying disease between children with or without pneumonia. Respiratory symptoms were initially present in 58 cases. Seven (12%) had pneumonia. Among the 99 asymptomatic cases only one (1%) patient had a pneumonia (P = 0.0041). This child had a positive blood culture for P. aeruginosa at the time of admission. None of the children had initial therapy modified on the basis of radiologic findings.

CONCLUSION

In this study, pneumonia is an unusual cause of fever (5%), especially in the absence of respiratory signs or symptoms (1%). Admission CXR should be reserved for the neutropenic pediatric oncology patient presenting with fever and abnormal respiratory findings.

Etiology of community-acquired pneumonia in hospitalized school-age children: evidence for high prevalence of viral infections

BACKGROUND

Community-acquired pneumonia (CAP) in young children is most commonly associated with viral infections; however, the role of viruses in CAP of school-age children is still inconclusive.

METHODS

Seventy-five school-age children hospitalized with CAP were prospectively evaluated for the presence of viral and bacterial pathogens. Nasopharyngeal washes were examined by polymerase chain reaction for viruses and atypical bacteria. Antibody assays to detect bacterial pathogens in acute-phase and convalescent-phase serum samples were also performed.

RESULTS

A viral infection was identified in 65% of cases. Rhinovirus RNA was detected in 45% of patients; infection with another virus occurred in 31%. The most common bacterial pathogen was Mycoplasma pneumoniae, which was diagnosed in 35% of cases. Chlamydia pneumoniae DNA was not detected in any patient; results of serological tests were positive in only 2 patients (3%). Mixed infections were documented in 35% of patients, and the majority were a viral-bacterial combination.

CONCLUSIONS

The high prevalence of viral and mixed viral-bacterial infections supports the notion that the presence of a virus, acting either as a direct or an indirect pathogen, may be the rule rather than the exception in the development of CAP in school-age children requiring hospitalization.

Do rhinoviruses cause pneumonia in children?

Rhinoviruses are the most common precipitants of the common cold and have been associated with different infections of the respiratory tract, such as otitis media and sinusitis. They have also been implicated in the induction of acute asthma exacerbations, most of which are preceded by a common cold. Although in several occasions, mainly in immunocompromised hosts, severe lower respiratory tract infections have been attributed to rhinovirus infections, it is still unclear whether and to what extent these viruses contribute as pathogens in community-acquired pneumonia. Current mechanistic data suggest that rhinoviruses could be the cause of pneumonia in immunocompetent subjects. This notion is supported by epidemiological evidence, however, more clinical studies are needed to assess the actual burden.

Viral pneumoniae in children: incidence and aetiology

Community-acquired pneumonia remains a common and serious illness, which affects children of all age groups. The spectrum of causative organisms is wide and it differs according to the age of the patients. With the advent of new and improved diagnostic techniques our understanding of the aetiology of the disease has been improved considerably. Viruses have been shown to cause up to 90% of pneumonias, especially in the first year of life, with the respiratory syncytial virus to be the most important pathogen and this percentage decreases to approximately 50% by school age. Viral pneumonias frequently are complicated by bacterial infections and mixed infections are identified in 30% of the cases. The precise role of viruses and bacteria in these cases, remains to be clarified.

Incidence of community-acquired pneumonia in children caused by Mycoplasma pneumoniae: Serological results of a prospective, population-based study in primary health care

OBJECTIVE

The objective of the present study was to assess the incidence of community-acquired pneumonia (CAP) in children caused by Mycoplasma pneumoniae.

METHODOLOGY

During 12 months in 1981-1982, all CAP cases in a defined child population were registered. M. pneumoniae aetiology, initially measured by complement fixation (CF) test, was in 1999 supplemented by measurement of IgG and IgM antibodies using enzyme immunoassays (EIA).

RESULTS

M. pneumoniae was detected in 61 (30%) of 201 paediatric CAP cases, being the most common aetiological agent in those 5 years of age or over. At that age, M. pneumoniae was responsible for over 50% of cases, and over 90% of mycoplasmal cases were treated as outpatients. The EIA detected 17 new cases over and above the 44 detected by CF, while CF alone revealed 10 cases. The incidence of M. pneumoniae CAP increased with age, being over 10/1000 children at the age of 10 years or more. Co-infections with Streptococcus pneumoniae and Chlamydia pneumoniae were present in over 30% and 15%, respectively, of mycoplasmal CAP cases.

CONCLUSION

M. pneumoniae is a common cause of paediatric CAP in primary health care, and co-infections with S. pneumoniae are common. Both S. pneumoniae and M. pneumoniae should be taken into account when starting antibiotics for children with CAP.

Community-acquired pneumonia in children

Community acquired pneumonia (CAP) is common in childhood. Viruses account for most cases of CAP during the first two years of life. After this period, bacteria such as Streptococcus pneumoniae, Mycoplasma pneumoniae and Chlamydia pneumoniae become more frequent. CAP symptoms are nonspecific in younger infants, but cough and tachypnea are usually present in older children. Chest x-ray is useful for confirming the diagnosis. Most children can be managed empirically with oral antibiotics as outpatients without specific laboratory investigations. Those with severe infections or with persistent or worsening symptoms need more intensive investigations and may need admission to hospital. The choice and dosage of antibiotics should be based on the age of the patient, severity of the pneumonia and knowledge of local antimicrobial resistance patterns. The Canadian Paediatric Society recommends the use of the heptavalent conjugate pneumococcal vaccine, which is efficacious in reducing chest x-ray positive pneumonia by up to 20%.

Influenza A community-acquired pneumonia in East London infants and young children

BACKGROUND

Community-acquired pneumonia (CAP) is common in young children, but there are few data in Europe on influenza A virus as a cause of childhood CAP. The aim of this study was to determine the relative contributions of different etiologic agents to CAP in children.

METHODS

This was a 6-month prospective study of pediatric accident and emergency and general practice consultations with a diagnosis of CAP. Nasopharyngeal aspirates for viral immunofluorescence and PCR studies and blood cultures for bacterial studies were taken from 51 children with symptoms, signs and chest radiographic features that satisfied a diagnosis of pneumonia.

RESULTS

An etiologic agent was isolated from 25 patients (49%). A viral cause was identified in 22 patients (43%), and influenza A virus and respiratory syncytial virus (RSV) were detected in 16 and 18% of all cases, respectively. Only four patients (8%) had a positive bacterial blood culture; three had Streptococcus pneumoniae and one had Neisseria meningitidis W135. Mycoplasma pneumoniae was detected in 2 children, and mixed infections were detected in 5 (10%). The use of viral PCR increased the detection rate of influenza A virus by 100%.

CONCLUSION

Influenza A virus caused more than one-third of all viral CAP cases, a rate comparable with that of RSV CAP. Viral PCR doubled the diagnostic yield of influenza A virus. The clinical burden of influenza A CAP was comparable with that of RSV CAP, as measured by the duration of fever, hospital stay and total duration of illness.

Serologically indicated pneumococcal pneumonia in children: a population-based study in primary care settings

The aim of the study was to assess age-specific incidences of community-acquired pneumonia (CAP) caused by Streptococcus pneumoniae and diagnosed serologically in a child population. The study was population-based, and prospective, and performed in primary health care settings. During a surveillance period of 12 months from 1981-1982, all pneumonia cases in a defined child population (57% urban residents) were registered prospectively. In total, 201 CAP cases were diagnosed (mean age 5.6 years; 57% boys; 58% urban residents). S. pneumoniae etiology was studied by antibody and immune complex (IC) assays to C-polysacchride (C-PS), type-specific capsular polysaccharides (CPS), and to pneumolysin (Ply), in acute and convalescent sera. Serologic evidence of S. pneumoniae etiology was indicated in 57(28%) cases, 35(61%) being mixed infections with other microbes. The distribution of pneumococcal cases was 44%, 30% and 26% in the three 5-year age groups, respectively. There were 33 (58%) males and 34 (60%) urban residents. In total, 26 cases were identified by antibody assays and 35 cases by IC assays, 26/35 being positive in acute sera. Responses to C-PS, CPS and Ply, when antibody and IC results are combined, were found equally often in 23-25 cases. The total annual incidence of pediatric S. pneumoniae CAP was 6.4/1000/year. S. pneumoniae etiology was found in 28% of the children and was similar at all ages. The incidence of pneumococcal CAP was assessed for the first time, being high (19/1000/year) in 0- to 4-year-old urban boys and rather stable (5-9/1000/year) in all other groups by age, sex and residence.

Benefits and costs of immunization of children with pneumococcal conjugate vaccine in Canada

To estimate cost-effectiveness of routine and catch-up vaccination of Canadian children with seven-valent pneumococcal conjugate vaccine, a simulation model was constructed. In base scenario (vaccination coverage: 80%, and vaccine price: 58 dollars per dose), pneumococcal disease incidence reduction would be superior to 60% for invasive infections, and to 30% for non-invasive infections, but the number of deaths prevented would be small. Annual costs of routine immunization would be 71 million dollars (98% borne by the health system). Societal benefit to cost ratio would be 0.57. Net societal costs per averted pneumococcal disease would be 389 dollars and 125,000 per life-year gained (LYG). Vaccine purchase cost is the most important variable in sensitivity analyses, and program costs would be superior to societal benefits in all likely scenarios. Vaccination would result in net savings for society, if vaccine cost is less than 30 dollars per dose. Economic indicators of catch-up programs are less favorable than for routine infant immunization.

Streptococcus pneumoniae-related illnesses in young children: secular trends and regional variation

BACKGROUND

Children <2 years old have been targeted for routine pneumococcal conjugate vaccine. Laboratory-confirmed illnesses represent a minority of all medical care utilization for pneumococcal disease.

OBJECTIVES

To evaluate trends in medical care utilization for Streptococcus pneumoniae-related illnesses before introduction of pneumococcal conjugate vaccine (1995 to 1999) and to evaluate regional variation in utilization.

METHOD

Retrospective cohort analysis with the use of computerized billing data of children <2 years old enrolled in Tennessee (Medicaid program) and the Rochester, NY area (commercial and Medicaid managed care plans). Secular trends (1995 to 1999) analysis included 316 519 person-years in Tennessee Medicaid. Regional variation (1998 to 1999) analysis included 130 525 person-years in Tennessee and 26 140 and 3184 person-years in commercial and Medicaid plans, respectively, in the Rochester, NY area.

RESULTS

From 1995 to 1999 in Tennessee, the net increase in medical care visits was 12% for pneumococcal and nonspecific pneumonia and invasive disease, 11% for otitis media and 11% for other acute respiratory conditions. Analysis of trends indicated that a significant vaccine effect could be detected if utilization rates declined by 32, 9 and 21%, respectively. In the Tennessee Medicaid population, rates of pneumococcal and nonspecific pneumonia and invasive disease were 60% higher than in either the New York Medicaid or the commercial populations. Children with commercial insurance had the highest medical care utilization for otitis media.

CONCLUSIONS

Geographic variation and large population differences in medical care utilization among children < 2 years old in three study populations suggest that the benefits of vaccination may vary by region and by population. In the Tennessee Medicaid population, temporal trends and year-to-year variability of pneumococcal-related outcomes were observed from 1995 to 1999. In this population a 10% decline in otitis media visits after the introduction of pneumococcal conjugate vaccine could be detected by trend analysis.

Formulations of antibiotics for children in primary care: effects on compliance and efficacy

This review article is designed for pediatricians as well as primary care physicians in the outpatient setting as a clinical guide to antibiotic selection. It emphasizes variables related to compliance as well as efficacy. The aim is to give recommendations as to the choice of antibiotics, depending on factors such as taste, cost, efficacy, and compliance. Common bacterial pathogens causing infections in children are reviewed, along with their susceptibility patterns to antimicrobial agents. Emerging mechanisms of resistance, particularly the increasing resistance of pneumococci to beta-lactam antibiotics, are discussed because of their importance to antibiotic selection. Previously published studies that have examined the treatment of common outpatient infections in children, such as otitis media, streptococcal tonsillopharyngitis, and sinusitis, are summarized. Adverse reactions associated with antibiotics, second in importance only to efficacy, are reviewed. Finally, compliance issues, which include palatability, cost, duration of therapy, and administration frequency, are analyzed using recently published information related to each of these issues. The efficacy of the commonly used antibiotics for urinary tract infections, pneumonia, and streptococcal pharyngitis does not vary significantly; however, for otitis media and sinusitis, some studies have shown that treatment efficacy with the antibiotic does not vary significantly from that with placebo. Likewise, adverse reactions rarely provide a basis for antibiotic selection, since virtually all antibiotics are generally well tolerated. The final factor, compliance, is a major issue in determining both first- and second-line therapy of common outpatient infections in children. Although cost is not a factor in compliance in countries such as the UK where no copayment is required for pediatric drugs, it is of major importance in the US. This is followed by palatability, administration duration and finally administration frequency. As a group, cephalosporins are generally the best tasting but are relatively more expensive than macrolides. Antibiotics that can be given for 5 days, and just once or twice daily, are preferred by most parents and physicians. Since final assessment of antibiotic choice is likely to vary considerably among healthcare personnel, decisions must be made on an individual basis.

Differentiation of bacterial and viral pneumonia in children

BACKGROUND

A study was undertaken to investigate the differential diagnostic role of chest radiographic findings, total white blood cell count (WBC), erythrocyte sedimentation rate (ESR), and serum C reactive protein (CRP) in children with community acquired pneumonia of varying aetiology.

METHODS

The study population consisted of 254 consecutive children admitted to hospital with community acquired pneumonia diagnosed between 1993 and 1995. WBC, ESR, and CRP levels were determined on admission. Seventeen infective agents (10 viruses and seven bacteria) were searched for. Chest radiographs were retrospectively and separately reviewed by three paediatric radiologists.

RESULTS

A potential causative agent was found in 215 (85%) of the 254 cases. Bacterial infection was found in 71% of 137 children with alveolar infiltrates on the chest radiograph, while 72% of the 134 cases with a bacterial pneumonia had alveolar infiltrates. Half of the 77 children with solely interstitial infiltrates on the chest radiograph had evidence of bacterial infection. The proportion of patients with increased WBC or ESR did not differ between bacterial and viral pneumonias, but differences in the CRP levels of >40 mg/l, >80 mg/l, and >120 mg/l were significant although the sensitivity for detecting bacterial pneumonia was too low for use in clinical practice.

CONCLUSIONS

Most children with alveolar pneumonia, especially those with lobar infiltrates, have laboratory evidence of a bacterial infection. Interstitial infiltrates are seen in both viral and bacterial pneumonias.

Emerging resistance to antibiotics against respiratory bacteria: impact on therapy of community-acquired pneumonia in children

Perhaps because of its etiologic complexity, community-acquired pneumonia (CAP) in infants and children remains a significant problem worldwide. Over the last few years, difficulties related to CAP treatment in children have greatly increased because of the emergence of resistance to the most widely used antibiotics against some of the bacterial pathogens involved in the development of the disease. There are few data describing the impact of antibiotic resistance on clinical outcomes in CAP, but many experts believe that the clinical impact is limited. We here discuss the prevalence of different etiologic agents in CAP of children, the diagnostic criteria, problems related to antibiotic resistance, therapeutic strategies, and future implications.

Diagnosis of Streptococcus pneumoniae lower respiratory infection in hospitalized children by culture, polymerase chain reaction, serological testing, and urinary antigen detection

A prospective study of 154 consecutive high-risk hospitalized children with lower respiratory infections was conducted to determine the clinical utility of a pneumolysin-based polymerase chain reaction (PCR) assay compared with blood and pleural fluid cultures and serological and urinary antigen tests to determine the incidence of Streptococcus pneumoniae. Whole blood, buffy coat, or plasma samples from 67 children (44%) tested positive by PCR. Sensitivity was 100% among 11 promptly tested culture-confirmed children and specificity was 95% among control subjects. Age, prior oral antibiotic therapy, and pneumococcal nasopharyngeal colonization did not influence PCR results, whereas several surrogates of disease severity were associated with positive tests. Although serological and urinary antigen tests had comparable sensitivity, specificity varied among infected children, and statistical agreement among all assays was limited. These findings support the use of PCR tests to evaluate the protective efficacy of pneumococcal conjugate vaccines and to identify promptly children with pretreated or nonbacteremic pneumococcal lower respiratory infections.

Clinical profile of serologically diagnosed pneumococcal pneumonia

OBJECTIVE

To describe the characteristics of serologically diagnosed pneumococcal pneumonia and compare them with those of respiratory syncytial virus (RSV) pneumonia and bacteremic pneumococcal pneumonia.

METHODS

IgG antibodies to pneumococcal pneumolysin and C-polysaccharide as well as immune complexes containing IgG antibodies to pneumolysin and C-polysaccharide were measured from acute and convalescent sera of 254 children with community-acquired pneumonia. Evidence of pneumococcal infection was found in 93 children. Clinical and laboratory data were retrospectively collected from the records of 38 children with sole (all tests for 16 other microbes negative) pneumococcal pneumonia and compared with 26 sole RSV-induced pneumonia from the present series and with the data of our 85 bacteremic pneumococcal pneumonia cases reported earlier.

RESULTS

Serologically diagnosed sole pneumococcal pneumonia clinically overlapped with RSV pneumonia, but RSV pneumonia was more often associated with tachypnea (45% vs. 17%, P < 0.05) and low white blood cell counts (means, 12.0 x 109/l vs. 20.8 x 109/l; P < 0.001) as well as low serum C-reactive protein levels (means, 28 mg/l vs. 137 mg/l; P < 0.001). Alveolar infiltrates were found in 15% of chest radiographs of children with RSV pneumonia compared with 76% of those in children with sole pneumococcal pneumonia (P < 0.001). Patients with bacteremic pneumonia more often appeared ill (79% vs. 50%, P < 0.001) and more often had typical pneumococcal pneumonia with high fever, leukocytosis and lobar infiltrates in their chest radiographs (70% vs. 34%, P < 0.05) than those with serologically diagnosed pneumococcal pneumonia.

CONCLUSIONS

Serologically detected pneumococcal pneumonia differs significantly from RSV pneumonia in laboratory and chest radiography findings, but the clinical signs and symptoms overlap considerably. Bacteremic pneumococcal pneumonia is a more severe illness than the serologically diagnosed one.

Management of fever without source in infants and children

Twenty percent of febrile children have fever without an apparent source of infection after history and physical examination. Of these, a small proportion may have an occult bacterial infection, including bacteremia, urinary tract infection (UTI), occult pneumonia, or, rarely, early bacterial meningitis. Febrile infants and young children have, by tradition, been arbitrarily assigned to different management strategies by age group: neonates (birth to 28 days), young infants (29 to 90 days), and older infants and young children (3 to 36 months). Infants younger than 3 months are often managed by using low-risk criteria, such as the Rochester Criteria or Philadelphia Criteria. The purpose of these criteria is to reduce the number of infants hospitalized unnecessarily and to identify infants who may be managed as outpatients by using clinical and laboratory criteria. In children with fever without source (FWS), occult UTIs occur in 3% to 4% of boys younger than 1 year and 8% to 9% of girls younger than 2 years of age. Most UTIs in boys occur in those who are uncircumcised. Occult pneumococcal bacteremia occurs in approximately 3% of children younger than 3 years with FWS with a temperature of 39.0 degrees C (102.2 degrees F) or greater and in approximately 10% of children with FWS with a temperature of 39.5 degrees C (103.1 degrees F) or greater and a WBC count of 15, 000/mm(3) or greater. The risk of a child with occult pneumococcal bacteremia later having meningitis is approximately 3%. The new conjugate pneumococcal vaccine (7 serogroups) has an efficacy of 90% for reducing invasive infections of Streptococcus pneumoniae. The widespread use of this vaccine will make the use of WBC counts and blood cultures and empiric antibiotic treatment of children with FWS who have received this vaccine obsolete.