Recovery of beta-lactamase producing bacteria in pediatric infections

The presence of beta-lactamase producing bacteria (beta LPB) was investigated in specimens obtained from 1469 children who presented with infections of the skin and soft tissue (648), upper respiratory tract (514), pulmonary sites (137), surgical sites (113), and other (57). Of 4989 bacterial isolates recovered, 910 (18%) were beta LPB, 492 (54%) aerobes, and 418 (46%) anaerobes. The beta LPB were recovered in 751 (51%) of the children. The most frequently recovered beta LPB was Staphylococcus aureus, which was recovered in 356 (47%) patients. Most isolates were recovered from patients with skin and soft-tissue infections (68% of patients), upper respiratory tract infections (49%), and pulmonary infections (35%). Bacteroides fragilis group was isolated in 35% of patients with beta LPB, mostly from surgical infections (98% of patients), pulmonary infections (36%), skin and soft-tissue infections (25%), and upper respiratory tract infections (20%). Twenty-five percent of the Bacteroides melaninogenicus group produced beta-lactamase. These organisms were recovered in 15% of patients with beta LPB. They were recovered in upper respiratory tract infections (38% of patients), pulmonary infections (22%), and skin and soft-tissue infections (7%). Other beta LPB were Pseudomonas aeruginosa (8% of total patients with beta LPB), Escherichia coli (4%), Bacteroides oralis (3%), Klebsiella pneumoniae (3%), Haemophilus influenzae (2%), Proteus (1%), and Branhamella catarrhalis (1%). The role of beta LPB in the failure of penicillin to eradicate many of the infections is discussed.     

Deficiency in interferon production by leukocytes from children with recurrent respiratory infections

In vitro interferon production by peripheral blood mononuclear cells from 50 children suffering from recurrent upper respiratory tract infections was examined, and compared with that of 50 healthy children. Five respiratory pathogenic viruses and Mycoplasma pneumoniae were used as inducers. Cells from every child responded to at least three out of the six inducers by interferon production. As a group, cultures prepared from patient cells showed decreased production of IFN when stimulated with adeno, rhino, corona or RS viruses or with the mycoplasma. Similar trend between the two groups of children was seen as regards influenza A virus induced IFN production in leukocyte cultures. These results corroborate our previous findings that relative deficiency in interferon production appears to be inducer-specific, and suggest that this phenomenon may have a role in the pathogenesis of recurrent respiratory infections.     

Immune responses induced by Pelargonium sidoides extract in serum and nasal mucosa of athletes after exhaustive exercise: Modulation of secretory IgA, IL-6 and IL-15

The evidence that exhaustive exercise may compromise the immune response is mainly confirmed by upper respiratory tract infections which are probably related to the decrease in secretory immunoglobulin A in the upper airway mucosa and/or profile changes of systemic cytokines as well as local cytokines of the upper respiratory tract. An extract from Pelargonium sidoides roots is currently used to treat infections in the upper airways. The aim of the present study was to evaluate the action of this herbal medicine on the immune response of athletes submitted to an intense running session by analyzing the production of immunoglobulin A in their saliva and of cytokines both locally and systemically, using a placebo as control. The results show that Pelargonium sidoides extract modulates the production of secretory immunoglobulin A in saliva, both interleukin-15 and interleukin-6 in serum, and interleukin-15 in the nasal mucosa. Secretory immunoglobulin A levels were increased, while levels of IL-15 and IL-6 were decreased. Based on this evidence, we suggest that this herbal medicine can exert a strong modulating influence on the immune response associated with the upper airway mucosa in athletes submitted to intense physical activity.     

Management and outcome of winter upper respiratory tract infections in children aged 0-9 years.

Age-specific incidences for upper respiratory tract infections in children from a new-town population during 1975-7 were studied, and 965 consecutive upper respiratory tract infections in children aged under 10 during two winters were analysed in detail. Significantly different management plans made by seven doctors did not correlate with the clinical outcome as judged by complications, recall rates, and demand for treatment for similar episodes in the future. Two hundred and thirty-two children (24%) returned for another consultation for the same episode of upper respiratory tract infection. The main reason for these repeat consultations seemed to be that parental expectations about the natural history of the illness were not fulfilled. More realistic parental expectations might be set and safer clinical standards maintained if doctors warned parents about symptoms such as cough and occasional diarrhoea or vomiting that are commonly associated with upper respiratory tract infections in children.     

Management of upper respiratory tract infections by telephone.

We surveyed Utah general internists (N = 134) regarding their attitudes toward and practices associated with telephone management of upper respiratory tract infections. The questionnaire contained 3 case vignettes--viral upper respiratory tract infection, streptococcal pharyngitis, and acute infectious epiglottitis--and a series of questions were asked about telephone diagnosis, management preferences (clinic versus telephone), and telephone management practices. The 53 respondents (40%) were able to make important diagnostic distinctions about upper respiratory tract infections from a written vignette. As the likelihood of a complicated or serious condition increased, patients would be appropriately triaged for clinical evaluation. Most internists would make a written record of the telephone conversation. Only 1 internist of the 53 would charge for telephone management.     

Respiratory Infections in Adults with Atopic Disease and IgE Antibodies to Common Aeroallergens

Background

Atopic diseases, including allergic rhinitis, allergic dermatitis and asthma, are common diseases with a prevalence of 30–40% worldwide and are thus of great global public health importance. Allergic inflammation may influence the immunity against infections, so atopic individuals could be susceptible to respiratory infections. No previous population-based study has addressed the relation between atopy and respiratory infections in adulthood. We assessed the relation between atopic disease, specific IgE antibodies and the occurrence of upper and lower respiratory infections in the past 12 months among working-aged adults.

Methods and Findings

A population-based cross-sectional study of 1008 atopic and non-atopic adults 21–63 years old was conducted. Information on atopic diseases, allergy tests and respiratory infections was collected by a questionnaire. Specific IgE antibodies to common aeroallergens were measured in serum. Adults with atopic disease had a significantly increased risk of lower respiratory tract infections (LRTI; including acute bronchitis and pneumonia) with an adjusted risk ratio (RR) 2.24 (95% confidence interval [CI] 1.43, 3.52) and upper respiratory tract infections (URTI; including common cold, sinusitis, tonsillitis, and otitis media) with an adjusted RR 1.55 (1.14, 2.10). The risk of LRTIs increased with increasing level of specific IgE (linear trend P = 0.059).

Conclusions

This study provides new evidence that working-aged adults with atopic disease experience significantly more LRTIs and URTIs than non-atopics. The occurrence of respiratory infections increased with increasing levels of specific IgE antibodies to common aeroallergens, showing a dose-response pattern with LRTIs. From the clinical point of view it is important to recognize that those with atopies are a risk group for respiratory infections, including more severe LRTIs.     

Cigarette smoke-promoted acquisition of bacterial pathogens in the upper respiratory tract leads to enhanced inflammation in mice

Background

Bacterial colonization and recurrent infections of the respiratory tract contribute to the progression of chronic obstructive pulmonary disease (COPD). There is evidence that exacerbations of COPD are provoked by new bacterial strains acquired from the environment. Using a murine model of colonization, we examined whether chronic exposure to cigarette smoke (CS) promotes nasopharyngeal colonization with typical lung pathogens and whether colonization is linked to inflammation in the respiratory tract.

Methods

C57BL/6 N mice were chronically exposed to CS. The upper airways of mice were colonized with nontypeable Haemophilus influenzae (NTHi) or Streptococcus pneumoniae. Bacterial colonization was determined in the upper respiratory tract and lung tissue. Inflammatory cells and cytokines were determined in lavage fluids. RT-PCR was performed for inflammatory mediators.

Results

Chronic CS exposure resulted in significantly increased numbers of viable NTHi in the upper airways, whereas NTHi only marginally colonized air-exposed mice. Colonization with S. pneumoniae was enhanced in the upper respiratory tract of CS-exposed mice and was accompanied by increased translocation of S. pneumoniae into the lung. Bacterial colonization levels were associated with increased concentrations of inflammatory mediators and the number of immune cells in lavage fluids of the upper respiratory tract and the lung. Phagocytosis activity was reduced in whole blood granulocytes and monocytes of CS-exposed mice.

Conclusions

These findings demonstrate that exposure to CS impacts the ability of the host to control bacterial colonization of the upper airways, resulting in enhanced inflammation and susceptibility of the host to pathogens migrating into the lung.     

Aetiology of upper respiratory tract infections in children in Arak city: a community based study

Viruses are frequent causes of upper respiratory tract infections in children. We investigated the viral aetiology of community-acquired upper respiratory tract infections (URIs) in young children treated as outpatients in community settings. During November 2008, nasal swab specimens were taken from children with recent onset of upper respiratory tract infections. The patients attended day care or primary schools; the specimens were randomly obtained by pediatricians from schools and childcare institutions and sent for identification by PCR method. A total of 300 specimens were collected. From all samples, 40.67% were positive for at least 1 virus, viz. adenovirus 11.76%, rhinovirus 9.8%, respiratory syncytial virus 6.08%, influenza virus 5.56%, parainfluenza virus 4.9%, enterovirus 2.94% and a combination of 2 viruses 2%. Clinical manifestations of the respiratory infections were as follows: 70.7% of the patients had coryza, 69.3% cough, 26% sneezing, 19.7% sore throat, 2.7% headache, 7.7% fever, 2.3% conjunctivitis, 1.3% abdominal pain and 1% hoarseness. The results of this study demonstrate that adenoviruses and rhinoviruses are the two most common viral agents isolated from pediatric outpatients with acute URIs in autumn in Arak City. Coryza and cough were the most common symptoms in children. Sore throat and hoarseness were more prevalent in infections caused by influenza virus, conjunctivitis in parainfluenza, and coryza in rhinovirus infections.     

Respiratory infections in the first year of life in children at risk of developing atopy.

Ninety-two infants, each of whom had one parent with asthma or hay fever, were followed up from birth to age of 1 year and 72 to the age of three years. During the first year of life respiratory symptoms, eczema, and respiratory viral infections were all reported. Within the first year 24 babies developed eczema; 28 had a wheal of 1 mm in diameter or more on prick skin testing with cutaneous allergens. Forty-three children had one or both of these characteristics and formed an atopic subgroup; by the same criteria, 49 children were non-atopic. The number of respiratory infections in the two groups was not significantly different; similar viruses were isolated from both groups. These viruses were associated with both upper and lower respiratory tract infections. Wheezing was a clinical feature in 12 children during lower respiratory tract infections. Of these babies six were atopic in the first year of life. Of the six non-atopic babies, one had eczema in the second year and five children developed raised total serum IgE values within the 3 years.     

Suppurative tonsillitis and sudden cardiac death due to physical training in a young soccer player

A teenager aged 17 was a professional soccer player, and was without symptoms. He died suddenly during physical exercise at the field. All reanimation efforts were unsuccessfull. At the forensic autopsy he had suppurative bacterial tonsillitis, subacute diffuse myopericarditis and narrowing of the ascending aorta of 10 mm. In Croatia the death rate among athletes reached 0.15/100,000, in athletes suffered of acute respiratory tract infections 0.34/100,000, in males who practice exercise recreatively 0.75/100,000 (p = 0.0014), in school children 1.0/100,000 (p = 0.0010). Physical exercise is contraindicated in acute respiratory tract infections. Every such case has to be treated by physician. When to start with physical training after suppurative-bacterial tonsillitis depends on disappearing of clinical signs, normalization of erythrocite sedimentation rate; of white cell count and serum level of C-reactive protein. Physical exercise is contraindicated in patients suffering of myopericarditis for at least 6 months. When to start exercise depends on disappearing of subjective symptoms and normalization of clinical and laboratory findings.     

Importance of exercise immunology in health promotion

Chronic physical exercise with adequate intensity and volume associated with sufficient recovery promotes adaptations in several physiological systems. While intense and exhaustive exercise is considered an important immunosuppressor agent and increases the incidence of upper respiratory tract infections (URTI), moderate regular exercise has been associated with significant disease protection and is a complementary treatment of many chronic diseases. The effects of chronic exercise occur because physical training can induce several physiological, biochemical and psychological adaptations. More recently, the effect of acute exercise and training on the immunological system has been discussed, and many studies suggest the importance of the immune system in prevention and partial recovery in pathophysiological situations. Currently, there are two important hypotheses that may explain the effects of exercise and training on the immune system. These hypotheses including (1) the effect of exercise upon hormones and cytokines (2) because exercise can modulate glutamine concentration. In this review, we discuss the hypothesis that exercise may modulate immune functions and the importance of exercise immunology in respect to chronic illnesses, chronic heart failure, malnutrition and inflammation.     

Serum penicillin G levels are lower than expected in adults within two weeks of administration of 1.2 million units

When introduced in the 1950s, benzathine penicillin G (BPG) was shown to be effective in eradicating group A beta-hemolytic streptococcus (GAS) for at least 3 weeks after administration. Several studies since the 1990s suggest that at 3–4 weeks serum penicillin G levels are less than adequate (below MIC⁹⁰ of 0.016 µg/ml). We studied these levels for 4 weeks after the recommended dose of BPG in military recruits, for whom it is used as prophylaxis against GAS. The 329 subjects (mean age 20 years) each received 1.2 million units BPG IM and gave sera 1 day post injection and twice more at staggered time points over 4 weeks. Serum penicillin G levels were measured by liquid chromatography/tandem mass spectometry. The half-life of serum penicillin G was 4.1 days. By day 11, mean levels were <0.02 µg/ml, and by day 15<0.01 µg/ml. Levels in more than 50% of the subjects were below 0.02 µg/ml on day 9, and <.01 µg/ml on day 16. There was no demonstrable effect of subject body-surface area nor of the four different lots of BPG used. These data indicate that in healthy young adults serum penicillin G levels become less than protective <2½ weeks after injection of 1.2 million units of BPG. The findings require serious consideration in future medical and public health recommendations for treatment and prophylaxis of GAS upper respiratory tract infections.     

Chinchilla and murine models of upper respiratory tract infections with respiratory syncytial virus

Respiratory syncytial virus (RSV) is a major cause of lower respiratory tract infections in infants and the elderly. While the primary infection is the most serious, reinfection of the upper airway throughout life is the rule. Although relatively little is known about either RSV infection of the upper respiratory tract or host mucosal immunity to RSV, recent literature suggests that RSV is the predominant viral pathogen predisposing to bacterial otitis media (OM). Herein, we describe mouse and chinchilla models of RSV infection of the nasopharynx and Eustachian tube. Both rodent hosts were susceptible to RSV infection of the upper airway following intranasal challenge; however, the chinchilla proved to be more permissive than the mouse. The chinchilla model will likely be extremely useful to test the role of RSV in bacterial OM and the efficacy of RSV vaccine candidates designed to provide mucosal and cytotoxic T-lymphocyte immunity. Ultimately, we hope to investigate the relative ability of these candidates to potentially protect against viral predisposal to bacterial OM.     

Etiologic Diagnosis of Lower Respiratory Tract Infections

Decision as to the role of infection in lower respiratory tract disease requires examination by culture of specimens known to be derived from the infra-laryngeal respiratory tract. Methods that involve the upper respiratory tract in collection of specimens entail the hazard of contamination by microbiota resident in the upper respiratory tract.The extrapulmonary approaches of cutting-needle biopsy and needle aspiration of intrathoracic disease have not been impressively productive of etiologic diagnosis of infections. While open-chest surgical biopsy has been a highly effective means to diagnosis, this approach does have special requirements in facilities and technical skills.Percutaneous transtracheal aspiration of tracheo-broncho-pulmonary secretions-exudates has been productive of useful information. Because of inherent simplicity and safety, transtracheal aspiration should precede resort to more demanding, difficult, dangerous procedures.     

Infective Factors in Exacerbations of Bronchitis and Asthma

Infections of the respiratory tract were studied in a group of families each containing a patient with chronic bronchitis or with asthma. A wide variety of infective agents may be associated with exacerbations in susceptible subjects, but the types of organism to which patients are most at risk differ according to the family structure. Exacerbations in the susceptible subject are more likely to be related to viral infections when the family contains children than when it does not.Two patients with asthma experienced frequent respiratory infections, many of which provoked attacks of asthma.     

Effectiveness of adenotonsillectomy in children with mild symptoms of throat infections or adenotonsillar hypertrophy: open,randomised controlled trial

Objective To assess the effectiveness of adenotonsillectomy in children with mild symptoms of throat infections or adenotonsillar hypertrophy.Design Open, randomised controlled trial.Setting 21 general hospitals and three academic centres in the Netherlands.Participants 300 children aged 2-8 years requiring adenotonsillectomy.Intervention Adenotonsillectomy compared with watchful waiting.Main outcome measures Episodes of fever, throat infections, upper respiratory tract infections, and health related quality of life.Results During the median follow up period of 22 months, children in the adenotonsillectomy group had 2.97 episodes of fever per person year compared with 3.18 in the watchful waiting group (difference -0.21, 95% confidence interval -0.54 to 0.12), 0.56 throat infections per person year compared with 0.77 (-0.21, -0.36 to -0.06), and 5.47 upper respiratory tract infections per person year compared with 6.00 (-0.53, -0.97 to -0.08). No clinically relevant differences were found for health related quality of life. Adenotonsillectomy was more effective in children with a history of three to six throat infections than in those with none to two. 12 children had complications related to surgery.Conclusion Adenotonsillectomy has no major clinical benefits over watchful waiting in children with mild symptoms of throat infections or adenotonsillar hypertrophy.     

569例呼吸道感染住院儿童7种常见呼吸道病毒病原学分析

目的了解呼吸道感染住院患儿呼吸道病毒的分布情况。方法选取2015年7月至2016年6月呼吸道感染的住院患儿病例,抽取鼻咽分泌物,采用直接免疫荧光法检测常见的7种病毒,即呼吸道合胞病毒(RSV)、甲型流感病毒(IVA)、乙型流感病毒(IVB)、副流感病毒1型(PIV1)、副流感病毒2型(PIV2)、副流感病毒3型(PIV3)、腺病毒(IVD)。结果共有569例样本送检,193例病毒检测阳性(33.92%),其中有3例为2种病毒的混合感染。男性共369例,女性共200例。其中RSV、PIV3、ADV的感染率居前三位。呼吸道病毒的感染率随着患儿年龄的增长逐渐下降,除新生儿外,6个月内的婴幼儿呼吸道病毒检出率最高。RSV检测阳性率自11月开始呈增高趋势,12月最高,达55.86%。PIV3的检出高峰出现在7月,达13.64%。结论 RSV是本地区儿童呼吸道感染最常见的病毒。呼吸道病毒的检出率与年龄、季节等因素有关。     

Meta-analysis of randomised controlled trials of selective decontamination of the digestive tract. Selective Decontamination of the Digestive Tract Trialists' Collaborative Group.

OBJECTIVE--To determine the clinical benefits of selective decontamination of the digestive tract in patients treated in intensive care units. DESIGN--Meta-analysis of 22 randomised trials that compared different combinations of oral non-absorbable antibiotics, with or without a systemic component, with no treatment in controls. SUBJECTS--4142 patients seen in general and specialised intensive care units around the world. 2047 received some form of antibiotic treatment, the remainder no prophylaxis. DATA ANALYSIS--Each trial was reviewed through direct contact with study investigators. Data collected were: the randomisation procedure, number of patients, number excluded from the analysis, and numbers of respiratory tract infections and deaths. Data were combined according to an intention to treat analysis with the Mantel-Haenszel-Peto method. MAIN OUTCOME MEASURES--Respiratory tract infections and total mortality. RESULTS--Selective decontamination of the digestive tract significantly reduced respiratory tract infections (odds ratio 0.37; 95% confidence interval 0.31 to 0.43). The value of the common odds ratio for total mortality (0.90; 0.79 to 1.04) suggested at best a moderate treatment effect, reaching statistical significance only when the subgroup of trials of topical and systemic treatment combined was considered separately (odds ratio 0.80; 0.67 to 0.97). No firm conclusions could be drawn owing to large variations in patient mix and severity within and between trials. CONCLUSIONS--The findings strongly indicate that selective decontamination significantly reduces infection related morbidity in patients receiving intensive care. They also highlight why definite conclusions about the effect of prophylaxis on mortality cannot be drawn despite the large number of trials available. Based on the most favourable results obtained by pooling data from trials in which combined topical and systemic treatment was used it may be estimated that 6 (range 5-9) and 23 (13-139) patients would need to be treated to prevent one respiratory tract infection and one death respectively.     

Special feature for the Olympics: effects of exercise on the immune system: overview of the epidemiology of exercise immunology

The application of epidemiological methods to exercise immunology is reviewed briefly, with particular reference to the possible influences of physical activity, exercise and training on susceptibility to upper respiratory infections. Available reports are arbitrarily rated in terms of limiting factors: the quality of the assessment of physical activity, the precision of diagnosis of upper respiratory infection and overall methodology. The pattern of physical activity has often been clearly established but, in part because of the problems associated with the competitive environment, assessments of infection and overall methodology have often been less than optimal. Although there is some evidence that susceptibility to infection is increased by either a single bout of very heavy activity or a period of heavy training, reports are far from unanimous, and in certain respects fail to meet the classical epidemiological criteria of a causal relationship. The issue is important to both the health and the success of the international competitor, and merits definitive investigation, using optimal methods to assess both activity patterns and infection.