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PubMed1988

Viral respiratory tract infection and exacerbations of asthma in adult patients.

The role of viral respiratory tract infections in acute exacerbations of asthma was studied prospectively in 31 patients with atopic asthma aged 15-56 years. Patients recorded symptom scores for asthma and peak expiratory flow rate daily for 11 months. In addition, they reported for detailed clinical, functional, and virological study every four weeks and as soon as possible after the onset of worsening asthma or symptoms suggesting a respiratory tract infection. Thirty viral identifications were made, of which 18 (60%) were associated with an exacerbation of asthma. Viral respiratory tract infection was identified in 18 (10%) of the 178 exacerbations of asthma, and in 10 (36%) of the 28 severe exacerbations. The frequency of viral identifications in 16 non-asthmatic, control subjects during the same period was similar. It is concluded that viral respiratory tract infections may cause or be associated with exacerbations of asthma in adults, and that they are an important factor in severe exacerbations.

Acute Disease↗

PubMed1976

[Longterm virological studies in chronic diseases of the respiratory tract I (author's transl)].

A longitudinal study on the occurrence of acute viral infection of the respiratory tract in chronic respiratory diseases was carried out from the middle of July 1973 to the middle of July 1975 in a special clinic for respiratory organs. In the present publication, the general plan of the study, aspects of the selection of the "index" patients, the collection andprocessing of the materail for investigation and the documentation of the clinical symptoms of intercurrent infections of the respiratory tract on schematized diagnostic report forms are described.

Acute Disease↗

PubMed1997

Antibiotic prescribing for adults with colds, upper respiratory tract infections, and bronchitis by ambulatory care physicians.

CONTEXT: Antibiotic use is associated with increased rates of antibiotic-resistant organisms. A previous study has shown that colds, upper respiratory tract infections, and bronchitis account for nearly one third of all antibiotic prescribing by ambulatory care physicians. How frequently antibiotics are prescribed for these conditions and for and by whom is not known. OBJECTIVES: To measure antibiotic prescription rates and to identify predictors of antibiotic use for adults diagnosed as having colds, upper respiratory tract infections, and bronchitis in the United States. DESIGN: Sample survey of practicing physicians participating in the National Ambulatory Medical Care Survey, 1992. SETTING: Office-based physician practices. SUBJECTS: Physicians (n=1529) completing patient record forms for adult office visits (n=28787). MAIN OUTCOME MEASURES: Antibiotic prescriptions for colds, upper respiratory tract infections, and bronchitis. RESULTS: Office visits for colds, upper respiratory tract infections, and bronchitis resulted in approximately 12 million antibiotic prescriptions, accounting for 21% of all antibiotic prescriptions to adults in 1992. A total of 51 % of patients diagnosed as having colds, 52% of patients diagnosed as having upper respiratory tract infections, and 66% of patients diagnosed as having bronchitis were treated with antibiotics. Female sex (odds ratio [OR], 1.65; 95% confidence interval [CI], 1.05-2.62) and rural practice location (OR, 2.25; 95% CI, 1.33-3.80) were associated with greater antibiotic prescription rates, whereas black race (OR, 0.44; 95% CI, 0.21-0.93) was associated with lower antibiotic prescription rates. Patient age, Hispanic ethnicity, geographic region, physician specialty, and payment sources were not associated with antibiotic prescription rates in the bivariate analysis. Multivariate logistic regression analysis identified only rural practice location (adjusted OR, 2.58; 95% CI, 1.39-4.76) to be independently associated with more frequent antibiotic prescriptions for colds, upper respiratory tract infections, and bronchitis. CONCLUSION: Although antibiotics have little or no benefit for colds, upper respiratory tract infections, or bronchitis, these conditions account for a sizable proportion of total antibiotic prescriptions for adults by office-based physicians in the United States. Overuse of antibiotics is widespread across geographical areas, medical specialties, and payment sources. Therefore, effective strategies for changing prescribing behavior for these conditions will need to be broad based.

Adult↗

PubMed2002

[Antibiotic resistance: infections of the upper respiratory tract and bronchi. When are antibiotics necessary?].

Antimicrobial resistance among respiratory tract pathogens has become an increasing problem worldwide during the last 10-20 years. The wide use of antimicrobial agents in ambulatory practice has contributed to the emergence and spread of antibiotic-resistant bacteria in the community, namely Streptococcus pneumoniae, Haemophilus influenzae and Moraxella catarrhalis. The pneumococcus has developed resistance to most antibiotics used for its treatment. Classes with important resistance problems include the beta-lactams, the macrolides, the lincosamides, trimethoprim-sulfamethoxazole, and the tetracyclines. Unfortunately, resistance to more than one class of antibiotics is common. In Haemophilus influenzae and Moraxella catarrhalis, resistance to beta-lactam antibiotics is the main concern currently. It is important to know the local resistance pattern of the most common respiratory tract pathogens in order to make reasonable recommendations for an empirical therapy for respiratory tract infection, when antibiotic therapy is indeed indicated.

Anti-Bacterial Agents↗

PubMed2003

Treatment of adults with community-acquired respiratory tract infections: results of a multicentric clinical trial with gatifloxacin.

Respiratory tract infections have an important clinical and economic impact and they are the most common indication for antibiotic use in outpatient practice. This prospective, multicenter non-controlled trial assessed the efficacy and safety of gatifloxacin in the treatment of community-acquired respiratory tract infections. Patients were treated with a daily oral dose of gatifloxacin 400 mg for 7-14 days. The diagnosis of respiratory infection was made based on the clinical condition and/or radiologic findings. A total of 5,044 adult patients with community-acquired respiratory infections was treated with gatifloxacin in different centers in Brazil between March 1, 2001, and October 31, 2001. Among the 5,044 patients treated, 1,501 patients (29.76%) had community-acquired pneumonia, 756 (14.99%) had acute exacerbation of chronic bronchitis and 2,787 (55.25%) had acute sinusitis. Of the total of patients treated, 3,607 (71.51%) were considered cured, 1,261 (25%) progressed with some clinical improvement, 28 (0.56%) presented a relapse, 56 (1.11%) failed to treatment and 92 (1.82%) were unable to be evaluated. Adverse events were described in 634 (12.57%) patients. The most common adverse events were: nausea (2.24%); dyspepsia (1.86%); diarrhea (0.79%); change in taste (0.46%); insomnia and irritability (0.22%); dizziness (0.77%); headache (0.42%); allergic reaction (0.18%); Central Nervous System alterations insomnia, agitation, anxiety (0.46%). This study showed that the treatment of respiratory tract infections with gatifloxacin was safe and efficient and had a low incidence of adverse events.

Adult↗

PubMed1997

Management of lower respiratory tract infections in out-patients.

Lower respiratory tract infections (LRTIs) are one of the most frequent medical conditions seen in out-patients. They all cause morbidity, and although most are minor some may be life-threatening, thus appropriate disease management is important. Clinical features are usually used to classify LRTIs, but this approach may be inaccurate. It may therefore be simpler to describe a patient's symptoms without applying a label, such as "bronchitis", since the latter means different things to different people. Classification of LRTIs should aim to aid management. The two main management decisions are: whether to manage the patient at home; and whether to prescribe antibiotics. Investigations are carried out in the hospital environment to aid these decisions, however in the community investigation in only a minority of cases are done as they are costly and impractical. Markers of severity of LRTI have been identified in a number of studies and their value in clinical practice is now being assessed, however most studies suggest that severely ill patients are correctly identified and admitted to hospital. Currently, antibiotics are used liberally for lower respiratory tract infections. However most infections are not bacterial in origin and will not be affected by such therapy. The idea that antibiotics are harmless placebos for such illnesses is no longer tenable since the appearance and rapid spread of antibiotic resistance in bacteria. Only in community-acquired pneumonia and some patients with exacerbations of chronic bronchitis do antibiotics actually alter the course of the illness. In those groups antibiotics should be targetted at the casual pathogens and in other groups such therapy should be avoided. Much current research interest is focused on determining which (if any) is the best antibiotic in these situations.

Ambulatory Care↗

PubMed1976

The incidence and aetiology of respiratory tract infections in general practice--with emphasis on Mycoplasma pneumoniae.

The incidence of respiratory tract infections in patients seeking medical advice at a community care centre (Dalby) during 1973 and 1974 was studied. About every third patient seen at this primary health station presented with signs of such infections. In the age groups less than 10, 10-19, 20-39, 40-59 and greater than or equal to 60 years, respiratory tract infections accounted for 65, 45, 32, 18 and 9% of the fotal number of diagnoses made during 1974. The aetiology of acute respiratory tract infections in a series of patients seen at this health station was studied. The series included randomly selected cases, but excluded children under seven years of age and patients presenting with signs of acute otitis media and tonsillitis. Attempts to establish the aetiology were made on the basis of the history, the clinical examination, and cultures for beta-haemolytic streptococci and Mycoplasma pneumoniae, complement foxation tests for influenza A and B, para-influenza 1, 2, and 3, adeno, cytomegalovirus and respiratory syncytial virus, and Chlamydia psittaci. Paul-Bunnell test and tests for cold agglutinins were also performed. With this test battery, an aetiological diagnosis was obtained in only 33% of the 101 patients studied. The findings suggest an infection with M.pneumoniae in 16%, with beta-haemolytic streptococci in 9%, and with viruses (adeno and para-influenza) in 7% of the patients. The present communication highlights the role of M.pneumoniae in upper respiratory infections, as few data have appeared on such infections in patients seen in general practice. The difficulty of establishing the aetiology of respiratory tract infections and the consequent treatment dilemma is discussed.

Adolescent↗

PubMed2000

A study of feline upper respiratory tract disease with reference to prevalence and risk factors for infection with feline calicivirus and feline herpesvirus.

A cross-sectional survey of a convenience sample of cats was carried out to determine the prevalence of and risk factors for respiratory tract disease, feline calicivirus (FCV) infection and feline herpesvirus (FHV) infection. Seven hundred and forty cats were studied; samples for isolation of FCV and FHV were obtained from 622 (84%). Data on individual cat and household variables were obtained by questionnaire for each cat and analysed using univariable and logistic regression analysis. Thirty-eight percent (282/740) of cats surveyed had respiratory tract disease. Eighteen of 24 predictor variables were found to be significantly (P<0.05) associated with the presence of respiratory tract disease in a cat on univariable analysis. Following logistic regression, several factors retained significance including isolation of FCV and FHV, younger cats (4-11 months of age) and multiple cat households. A negative association was found with breeding catteries and other types of household in comparison with rescue catteries. Overall, feline calicivirus was isolated from 162/622 (26%) of cats sampled; 33% of the cats with respiratory tract disease were FCV positive compared to 21% of healthy cats. Variables significantly associated with FCV isolation on logistic regression were the presence of respiratory tract disease and contact with dogs with and without respiratory tract disease. Feline herpesvirus was isolated from 30/622 (5%) of all cats sampled; 11% of cats with respiratory tract disease were FHV positive compared to 1% of healthy cats. Variables significantly associated with FHV isolation on univariable analysis included age, gender, and the presence of respiratory tract disease. Vaccination showed a negative association. Logistic regression analysis of the data for FHV was limited by the sample size and the low prevalence of FHV.

Age Factors↗

PubMed2003

The classification of viruses infecting the respiratory tract.

Following the boom in respiratory virology in the 1960s, species of rhinoviruses, coronaviruses, enteroviruses, adenoviruses, parainfluenza viruses and respiratory syncytial virus were added to influenza and measles viruses as causes of respiratory tract infection. In restricted patient groups, such as the immunocompromised, members of the family of herpesviruses including herpes simplex, cytomegalovirus, varicella-zoster virus, Epstein-Barr virus and human herpes virus 6 have also been associated with respiratory disease. This list of pathogens was extended last year with the discovery of a novel virus, the human metapneumovirus. More than 200 antigenically distinct viruses have been documented as causes of sporadic or epidemic respiratory infections in infants, children and adults. However, this varied and diverse group can be divided among six distinct families. Understanding some of the basic biology of these families gives an insight into possible strategies for diagnosis, control and therapy.

Adenoviridae↗

PubMed1997

Bovine respiratory tract disease caused by bovine viral diarrhea virus.

Although several viruses and bacteria are capable of inducing bovine respiratory tract disease, a pivotal organism in the cause of this complex disease may be bovine viral diarrhea virus (BVDV). Circumstantial evidence has long supported this hypothesis. It is frequently present in diseased respiratory tract tissues often together with other viruses or bacteria. Field observations suggest marked synergism occurs. Researchers have confirmed that, in most instances, the virus itself elicits only a mild respiratory tract disease in susceptible calves, but some strains may be much more pneumo-pathogenic than others. Experimental evidence now supports the hypothesis, that BVDV markedly enhances respiratory tract disease caused by IBRV, BRSV, or Pasteurella haemolytica; that it impairs pulmonary immunity; and that it, by itself, may produce mild respiratory tract disease.

Animals↗

PubMedDate not supplied

Antibiotic treatment and survival of nursing home patients with lower respiratory tract infection: a cross-national analysis.

PURPOSE: Although lower respiratory tract infections are a leading cause of death in frail elderly patients, few studies have compared treatments and outcomes. We assessed the effects of different antibiotic treatment strategies on survival of elderly nursing home residents with lower respiratory tract infections in the United States and the Netherlands, where treatment approaches are quite different. METHODS: We combined data from 2 prospective cohort studies of lower respiratory tract infections conducted in 36 nursing homes in the United States and 61 in the Netherlands. We included residents whose infections were treated with antibiotics: 806 in the United States and 415 in the Netherlands. Outcome measures were 1-month and 3-month mortality. We used logistic regression to adjust for differing illness severity. RESULTS: Dutch residents had higher mortality than US residents (28.1% vs 15.1% at 1 month, respectively; P <.001). After adjusting for illness severity with logistic regression, the differences between the Dutch and US populations were not significant (odds ratio 1.34; 95% confidence interval, 0.94-1.90). Predicted mortality was overestimated for more severely ill US residents at 1 month but not at 3 months. No antibiotic regimen was consistently associated with increased or decreased mortality. CONCLUSION: Despite differences in illness severity and treatment, adjusted mortality did not differ between the 2 countries. Although we cannot exclude a short-term survival benefit from more aggressive treatment in the United States, differences in baseline health appear prognostically more important than the type of antibiotic treatment.

Aged↗

PubMed1993

Advances in biologically based models for respiratory tract uptake of inhaled volatiles.

Physiologically based pharmacokinetic models for volatile organic chemicals typically describe the respiratory tract as a single compartment in which chemicals in the alveolar air space and the arterial blood are in instantaneous equilibrium. These models also assume that the distribution of chemical in the air-stream is uniform throughout the respiratory tract and that uptake is significant only in the alveolar region. A functional role for the upper respiratory tract in the uptake of volatile chemicals has been largely ignored. While these models have worked well for chemicals with low aqueous solubility in biological fluids, systemic uptake of highly soluble volatiles is overestimated. Thus, there is a significant effort to describe the critical determinants for uptake of soluble chemicals and to formulate models with more biologically relevant descriptions of respiratory tract structure and function. Investigators have addressed this problem from several viewpoints. Airflow patterns in the respiratory tract, regional metabolism, diffusion-dependent uptake, and the cyclic nature of respiration are now being incorporated into current models. Use of dosimetric models that incorporate relevant biology for inhaled chemicals will ultimately result in more meaningful human risk assessments.

Administration, Inhalation↗

PubMed1995

Pathogenesis of bacterial infections of the respiratory tract.

The main function of the lung is gas exchange, which means that the respiratory mucosa is constantly exposed to noxious substances and potentially infective agents inhaled from the environment. Despite this, in health the number of bacteria in the upper respiratory tract (nose and pernasal tissue) is low and the lower (bronchopulmonary) respiratory tract is sterile. However, respiratory tract infections are common in humans, either due to malfunction of a complex array of defence mechanisms or because of the virulence of a particular microorganism. The pathogenesis of these infections is discussed.

Defense Mechanisms↗

PubMed1996

[Clinical characteristics of chronic sinusitis with different lower respiratory tract diseases].

We determined the clinical characteristics of chronic sinusitis in patients with different lower respiratory tract diseases. Sinusitis was divided into three groups. The first group was sinusitis with bronchial asthma. The second group was sinusitis with chronic bronchitis, bronchiectasis or diffuse panbronchiolitis. This type of sinusitis is generally called sinobronchial syndrome (SBS). The third group was sinusitis without lower respiratory tract disease. Because the pathogenesis of these lower respiratory tract diseases differs with the diseases, the pathogenesis of sinusitis accompanied by these lower respiratory tract diseases also may be different. Clinical and laboratory examinations used in this study were rhinoscopy, X-ray examination of the paranasal sinuses, cytological study of nasal secretion and the saccharin test for the muco-ciliary function of the nasal mucosa. By rhinoscopic examination, no difference was found in the size of the nasal polyp among three groups. The results of other examinations were as follows. X-ray examination: Involvement of the ethmoid sinuses was greater than that of the maxillary sinuses in the patients with sinusitis with bronchial asthma. In contrast, involvement of the maxillary sinuses in SBS patients was greater than that of the ethmoid sinuses. Cytology of nasal secretion: Dominant inflammatory cells in the patients with sinusitis with bronchial asthma were eosinophils, while neutrophil were more frequently found in the SBS patients. Saccharin test: Most of the patients with bronchial asthma showed normal responses. In the SBS patients, however, only a few patients showed a normal response and the others showed prolonged responses. Clinical characteristics of the patients with sinusitis without lower respiratory diseases were more similar to those of the SBS patients. In conclusion, there were distinct differences in these clinical characteristics between sinusitis with bronchial asthma and SBS. These results suggest that the pathogenesis or the inflammatory process of sinusitis is heterogeneous and whether the inflammation is allergic or not may be important.

Adult↗

PubMed1979

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.

Anti-Bacterial Agents↗

PubMed2003

Respiratory tract infections in travelers: a review of the GeoSentinel surveillance network.

Respiratory tract infections are common in travelers, and improving our knowledge of risk factors associated with specific types of respiratory infections should enable implementation of better preventive strategies. Data collected by the GeoSentinel surveillance network were analyzed, and the most significant predictors for developing specific categories of respiratory infections while abroad were age, sex, season of travel, trip duration, and reason for travel. In particular, influenza was associated with travel to the Northern Hemisphere during the period of December through February, travel involving visits to friends or relatives, and trip duration of >30 days. Lower respiratory tract infections were associated with male sex and increasing age. Knowledge of the respiratory tract infections that occur in specific groups of travelers allows for the development of targeted pretravel preventive strategies to high-risk groups.

Adolescent↗

PubMed1995

Viral potentiation of bacterial superinfection of the respiratory tract.

Virus infections of the respiratory tract predispose it to bacterial superinfections. Epidemiological studies, clinical evidence of viral-bacterial co-infection and animal models of such interactions suggest a time course of events and several mechanisms by which viral potentiation may occur. It appears that structural and functional disruption of the respiratory mucosal epithelium is a major contributor to the synergistic effects of superinfection.

Animals↗

PubMed1987

[Physical therapy in diseases of the respiratory tract].

The therapy of the respiratory tract should always include physiotherapy. Out of the various possible kinds of application is to develop a strategic long-term programme according to the building-stone principle, especially of the chronical unspecific lung diseases. The most important subjects, coming into question, are the aerosol-therapy, the respiratory-therapy, the massage-treatment, the hydrotherapy, the climato- and health-resort-therapy and other kinds of physiotherapy. This contribution enters upon the importance and the possibilities of employment of the various subjects.

Aerosols↗