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Results for “RESPIRATORY TRACT”

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PubMed1988

[Clinical studies of cefpodoxime proxetil in respiratory tract infections].

Twelve patients with respiratory tract infections were treated with cefpodoxime proxetil (CS-807, CPDX-PR), a new cephem antibiotic. It was given orally at a dose of 200 mg 2 times a day for 4 approximately 15 days. Its clinical effects were evaluated as excellent in 1 case, good in 9 cases and poor in 2 cases. The efficacy rate was 83.3%. Its bacteriological effects were evaluated as eradication in 5 strains and decrement in 1 strain. The eradication rate was 83.3%. No adverse reactions and disorder of laboratory findings due to CPDX-PR were observed.

Administration, Oral↗

PubMed1987

[Incidence of deep respiratory tract infections].

The distribution of respiratory tract infections (RTI) among the general population is not uniform. The incidence in neonates and the elderly (older than 65) is 2 to 3 times higher than that in adults. Examinations to determine the responsible pathogen are conducted in less than 1% of cases of RTI. The overall incidence of Haemophilus influenzae and Streptococcus pneumoniae in hospitalized patients amounts to 13 to 27%. The incidences of Staphylococcus aureus, Klebsiella and Pseudomonas aeruginosa in intensive care units are approximately 20% each. The management of the disease should be based on an aetiological diagnosis, and must take the individual patient's condition into account. Examination of the sputum or bronchial rinsing fluid is still the most reliable form of diagnosis, however, a sufficient number of quantitative methods must be applied. In hospitalized--and especially intensive care--patients these methods are often successful in isolating H. influenzae and pneumococci which we cannot afford to ignore as pathogens.

Bacterial Infections↗

PubMed2001

Validation study of a diary for use in acute lower respiratory tract infection.

BACKGROUND: Despite lower respiratory tract infection (LRTi) being the most common illness treated by doctors, no validated outcome measure to assess symptom duration and severity has been developed for patient self-completion. METHODS: As part of a randomized control trial researching management of acute LRTi, an easy self-completion diary was formulated and validated against the 'measure yourself medical outcome profile 2' (MYMOP2), an instrument previously validated in general practice. RESULTS: Spearman rank correlations of the diary profile versus MYMOP2 profile at baseline (r = 0.62), day 11 (r = 0.81) and change in score over time (r = 0.51) indicate that our diary correlates significantly with MYMOP2. The standardized response mean of the diary profile (mean change/SD change) = 1.48, indicating sensitivity to change. CONCLUSION: This study shows that a simple symptom diary is internally reliable, valid and sensitive to change for acute LRTi. This instrument could be used as a routine measure of LRTi in further research in both primary and secondary care.

Humans↗

PubMed2002

Comparing respiratory-tract and hepatic exposure-dose relationships for metabolized inhaled vapors: a pharmacokinetic analysis.

Inhaled vapors that are metabolized locally in the respiratory-tract tissues and systemically in the liver and other organs have different dose-response relationships at the portal of entry compared to systemic target organs. For instance, inhaled chloroform and styrene cause cytotoxicity in the nasal cavity at concentrations much lower that those causing hepatic or renal toxicity. Here, we develop a physiologically based pharmacokinetic (PBPK) model that incorporates a multicompartment, unidirectional flow description of the respiratory tract within a whole-body model in order to estimate both respiratory tract and hepatic metabolism. We then use this model to study the difference in exposure-dose relationship between the respiratory-tract tissues and the liver. The integrated PBPK model confirms that for soluble vapors the exposure-dose curve for metabolism in respiratory-tract tissue will be shifted dramatically to lower concentrations compared to the exposure-dose relationship in systemic organs. This behavior is the result of direct air to tissue equilibration at the portal of entry while other systemic tissues only respond to concentrations in the blood. For cases where metabolism/metabolites of inhaled vapors produce local toxicity, portal of entry effects are expected at lower concentrations and, in general, will be the limiting response for setting reference concentrations (RfCs) for many compounds. The difference in dose-response relationships for metabolism in the respiratory tract versus systemic organs depends on blood/air and blood/tissue partition coefficients and on the degree of systemic extraction of the metabolized vapors.

Animals↗

PubMed1997

Dual infections of PRRSV/influenza or PRRSV/Actinobacillus pleuropneumoniae in the respiratory tract.

To study the effect of a previous porcine respiratory and reproductive syndrome-infection (PRRS) of the respiratory tract on influenza virus and Actinobacillus pleuropneumoniae (App) infections, 3-week-old specific-pathogen-free (spf) piglets were intranasally infected with PRRS virus. One week later, when the lung alveolar macrophages of PRRSV infected pigs were lowest in number, a second infection was applied by intranasal aerosol of influenza virus H3N2 or by endobronchial instillation of a mildly virulent App. The first experiment consisted of two groups (only influenza infection or dual PRRSV/influenza infection). A second experiment consisted of 4 groups (only influenza infection, only PRRSV infection, dual PRRSV/influenza infection and uninfected controls). At day 2, 4, 14 and 21 after influenza infection, two pigs were killed and sampled for virological and histopathological examination. Influenza H3N2 virus caused only a mild inflammation of the smaller bronchioli. Previous PRRSV infection did not influence clinical signs during influenza infection. Next, we studied in two experiments the effect of dual PRRSV/App infection during the acute stage at two days after App infection. In a third experiment, the influence of PRRSV on more chronic stages of App infection was studied at two weeks after the App infection. At the end of the experiments, the pigs were killed. Lungs were ranked according to size and kind of the lesions. Lesions were cut and measured, samples were taken for virological and histopathological examination. Statistical analysis of the ranked lung-lesions in the first experiment showed a distinct but small effect of previous PRRSV infection on the development of App-lesions. In PRRSV infected pigs. App produced a more severe disease. The second and third experiment however failed to show any influence of the previous PRRSV infection on the App infection. We conclude that previous PRRSV infection of the respiratory tract of spf pigs does not necessarily enhance the severity of secondary infections of the respiratory tract.

Actinobacillus Infections↗

PubMed2003

Ribosomal immunotherapy for recurrent respiratory tract infections in children.

Recurrent respiratory tract infections are common in children. They reflect the immaturity of the immune system in its encounter with environmental antigens. Little or no specific protective immune response has yet been established. These infections represent an important public health problem in terms of both treatment (anti-inflammatory or antibacterial drugs for children) and economy. Immunotherapy has been proposed as a means of preventing these recurrent infections by providing children with small doses of inactive bacterial antigens liable to trigger specific and protective immune responses. Among such drugs, ribosomal preparations (to which this review is limited) appear to be not only well tolerated, but also ideally targeted to induce mucosal responses. One preparation of ribosomal mucosal vaccine is commercially available in several countries. Numerous clinical trials in the world have confirmed the positive role of this mucosal ribosomal bacterial vaccine in significantly reducing the number of infections, courses of antibacterials, and absenteeism. In vitro and ex vivo investigations have confirmed that such vaccines indeed trigger protective specific immune responses.

Bacterial Vaccines↗

PubMed1993

Cefepime versus cefotaxime in the treatment of lower respiratory tract infections.

Patients with lower respiratory tract infection (LRTI) were randomized 2:1 to receive either cefepime 2 g i.v. bd or cefotaxime 2 g i.v. tds. Bronchopneumonia alone or associated with another LRTI was diagnosed in 30 of 37 cefepime recipients and in 11 of 18 cefotaxime recipients; other diagnoses included bronchitis, lobar pneumonia and aspiration pneumonia. The mean duration of treatment was 5.9 days in the cefepime group and 5.4 days in the cefotaxime group. There were no significant differences between the two groups with regard to clinical or bacteriological outcome. Treatment was associated with a satisfactory clinical response in 27 (73%) of 37 evaluable cefepime patients and in 10 (56%) of 18 evaluable cefotaxime patients. Treatment resulted in eradication of 33 (89%) of 37 pathogens in the cefepime group, including 13 of 15 strains of Staphylococcus aureus, and of 16 (73%) of 22 pathogens in the cefotaxime group, including eight of ten strains of S. aureus. Two Pseudomonas aeruginosa strains persisted in the cefotaxime group. The sole clinical adverse event reported was a rash in one cefepime patient which did not require discontinuation of treatment. No clinically relevant changes in laboratory test results were attributed to either agent. Cefepime twice daily and cefotaxime three times daily were of comparable safety and efficacy in the treatment of bronchopneumonia and other LRTIs.

Adult↗

PubMedDate not supplied

[Microbiocenosis of the mucous membranes of the upper respiratory tract and its correction with acipol in the treatment of patients with acute respiratory virus infections].

Clinical and laboratory evaluation of the preparation Acipol in 45 children greatly susceptible to acute respiratory virus infections (ARVI) was carried out. Simultaneously with the clinical analysis, the study of the microflora of the mucous membranes of the upper respiratory tracts and intestine, as well as the levels of secretory IgA in saliva and coprofiltrates before and after treatment, was made. The inclusion of Acipol into the therapy of ARVI patients facilitated their clinical convalescence, uncomplicated course of the disease, correction of disturbances in the biocenosis of the upper respiratory tracts and increased infectious resistance.

Acute Disease↗

PubMed2000

[Detection of Mycoplasma genitalium in throat by nested polymerase chain reaction and analysis of DNA sequencing in pediatric patients with acute upper respiratory tract infections].

OBJECTIVE: To explore the relation between Mycoplasma genitalium (Mg) and acute upper respiratory tract infection in pediatric patients by using nested polymerase chain reaction(nPCR) and analysis of DNA sequencing techniques. METHODS: The specimens of throat swab were obtained in 62 acute upper respiratory tract infections children and 80 health children. The two kinds of Mg species-specific, in which the sequences of I-III and V-VII variable regions of Mg 16Sr RNA gene were detected by using nPCR technique. DNA sequences of positive product were detected and analysed. RESULTS: The Positive rate of health children is 5% (4/80), while the acute upper respiratory tract infection children is 21% (13/62). The difference is significant (P < 0.001). The DNA sequences of positive product shows that: there are two point mutation(T-->C) in the sequences of V-VII variable regions of throat swab of one pediatric patient, other sequences are same as those Mg type strain(G-37T). CONCLUSIONS: Acute upper respiratory tract infection of pediatric patients have relation with Mg. There are Mg mutant strain in China.

Adhesins, Bacterial↗

PubMed1995

A critical appraisal of intratracheal instillation of benzo[a]pyrene to Syrian golden hamsters as a model in respiratory tract carcinogenesis.

Several experimental models have been developed to study respiratory tract carcinogenesis. The most widely applied in vivo model uses Syrian golden hamsters which receive intratracheal instillations of a suspension of benzo[a]pyrene (B[a]P) particles attached to ferric-oxide (Fe2O3) particles in saline; it was first described by Saffiotti et al. [1]. This model has several benefits compared with other experimental models; however, the large number of variables affecting the tumour response is a clear disadvantage because the tumour response is difficult to control. In this review, we describe a systematic analysis of various variables that may influence the tumour response of the respiratory tract with the aim to further standardize the method and increase, through that, its suitability and predictability. The most important variables influencing the tumour response, as shown by statistical analysis of 29 representative studies, turned out to be the administered dose and the particle size. Both these variables influence the actual dose and the contact-time of the B[a]P particles with the target cells. The present study does not support the widespread opinion that ferric-oxide particles enhance the tumour response of the respiratory tract. In conclusion to the present analysis, some recommendations are made which probably increase the predictability of the model.

Animals↗

PubMed2003

Current issues in the management of bacterial respiratory tract disease: the challenge of antibacterial resistance.

The worldwide burden of respiratory tract disease is enormous. Resistance to penicillins, macrolides, and cephalosporins is now detected among the leading bacterial pathogens that cause respiratory tract infections (RTIs)-Streptococcus pneumoniae, Haemophilus influenzae, and Moraxella catarrhalis. The increasing role of atypical/intracellular pathogens (eg, Chlamydia pneumoniae, Mycoplasma pneumoniae, Legionella pneumophila) in RTIs, as well as their increase in antibiotic resistance prevalence, continues to be of great concern. More recently introduced treatment options for RTIs include the newer respiratory fluoroquinolones, along with the macrolides and azalides. Although these agents demonstrate good activity against common respiratory pathogens, reduced susceptibility to these agents has been reported. The ketolides are recently developed antibacterial agents with targeted-spectrum activity against common respiratory tract pathogens, including atypical/intracellular pathogens, and a low potential for inducing resistance. These promising new drugs have shown in vitro and in vivo efficacy in the treatment of community-acquired RTIs, such as community-acquired pneumonia, acute exacerbations of chronic bronchitis, and acute bacterial maxillary sinusitis.

Animals↗

PubMedDate not supplied

Rhinovirus and the lower respiratory tract.

Human rhinoviruses (HRVs) are well-recognised causes of common colds and associated upper respiratory tract complications such as sinusitis and otitis media. This article reviews information linking HRV infection to illness in the lower respiratory tract. HRVs are capable of efficient replication in vitro at temperatures present in the tracheobronchial tree and have been shown to cause productive infection, elaboration of cytokines and chemokines, and up-regulation of cell surface markers in human bronchial epithelial cells. In situ hybridisation studies have proven that HRV infection occurs in the tracheobronchial tree following experimental infection. Clinical studies report that HRV infection is the second most frequently recognised agent associated with pneumonia and bronchiolitis in infants and young children and commonly causes exacerbations of pre-existing airways disease in those with asthma, chronic obstructive pulmonary disease or cystic fibrosis. HRV infection is associated with one-third to one-half of asthma exacerbations depending on age and is linked to asthma hospitalisations in both adults and children. Limited information implicates HRV infection as a cause of severe lower respiratory tract illness in older adults and in highly immunocompromised hosts, particularly bone marrow transplant recipients. More information is needed about the pathogenesis of HRV infection with regard to lower respiratory tract complications in these diverse patient groups. Given the large unmet medical need associated with HRV infections, safe and effective antiviral agents are needed for both prevention and treatment of these infections.

Adolescent↗

PubMed2003

Optimizing antibiotic prescribing for acute respiratory tract infections in an urban urgent care clinic.

OBJECTIVE: To decrease unnecessary antibiotic use for acute respiratory tract infections in adults in a point-of-service health care setting. DESIGN: Prospective, nonrandomized controlled trial. SETTING: An urban urgent care clinic associated with the major indigent care hospital in Denver, Colorado between October 2000 and April 2001. PATIENTS/PARTICIPANTS: Adults diagnosed with acute respiratory tract infections (bronchitis, sinusitis, pharyngitis, and nonspecific upper respiratory infection). A total of 554 adults were included in the baseline period (October to December 2000) and 964 adults were included in the study period (January to April 2001). INTERVENTIONS: A provider educational session on recommendations for appropriate antibiotic use recently published by the Centers for Disease Control and Prevention, and placement of examination room posters were performed during the last week of December 2000. Study period patients who completed a brief, interactive computerized education (ICE) module were classified as being exposed to the full intervention, whereas study period patients who did not complete the ICE module were classified as being exposed to the limited intervention. MEASUREMENTS AND MAIN RESULTS: The proportion of patients diagnosed with acute bronchitis who received antibiotics decreased from 58% during the baseline period to 30% and 24% among patients exposed to the limited and full intervention, respectively (P <.001 for intervention groups vs baseline). Antibiotic prescriptions for nonspecific upper respiratory tract infections decreased from 14% to 3% and 1% in the limited- and full-intervention groups, respectively (P <.001 for intervention groups vs baseline). CONCLUSION: Antibiotic use for adults diagnosed with acute respiratory tract infections can be reduced in a point-of-service health care setting using a combination of patient and provider educational interventions.

Acute Disease↗

PubMed1998

[Chemotherapeutics for treatment of influenza and other viral respiratory tract infections in children].

Therapeutic efficacy of remantadine and arbidole was studied in the clinical and laboratory observation of pediatric in- and outpatients with grippe and mixed viral infections in various seasonal epidemic. In the trial of remantadine 742 school children and 60 children at the age of 3 to 6 years with type A, B or A + B grippe, grippe in association with other acute viral respiratory tract infections or acute viral respiratory tract infections of nongrippe etiology were observed. 402 and 400 of them were given remantadine and placebo respectively. The drug was used in a single dose of 1.5 mg/kg body weight 3 times a day for 3 days. In the trial of arbidole 158 children at the age of 1 to 14 years with type A grippe, grippe + acute viral respiratory tract infection and acute viral respiratory tract infection of nongrippe etiology were observed. The arbidole daily dose of 10 mg/kg body weight was given in 4 portions for 5 days. Both the drugs were shown to be therapeutically efficient in all the grippe types and acute viral respiratory tract infections. The highest efficacy was observed when the use of the drugs was started at the early stages. With the use of the drugs the periods of fever, other intoxication signs and virus isolation decreased. No adverse reactions were recorded. The drugs had no inhibitory effect on the cellular and humoral immunity and on production of antiviral antibodies. The dynamics of the indices of the cellular immunity and macrophages confirmed the arbidole immunostimulating action.

Adolescent↗

PubMed2000

Antibiotic prescribing for patients with colds, upper respiratory tract infections, and bronchitis: A national study of hospital-based emergency departments.

STUDY OBJECTIVE: Antibiotics are often used to treat viral upper respiratory tract infections, even though they are usually ineffective. However, frequent inappropriate antibiotic use contributes to the emergence of drug-resistant bacterial pathogens. This study used a national database to evaluate antibiotic use in treating upper respiratory tract infections in emergency departments. METHODS: Data were obtained from the 1996 National Hospital Ambulatory Medical Care Survey. Antibiotic prescribing rates were examined for colds, upper respiratory tract infections, and acute bronchitis. Patients with comorbid conditions or secondary diagnoses, such as chronic obstructive pulmonary disease, pneumonia, sinusitis, and HIV, were excluded. Bivariate and multivariate analyses were used to assess predictors of antibiotic use. RESULTS: Overall, there were an estimated 2.7 million ED visits for colds, upper respiratory tract infections, and bronchitis by children and adults in 1996. Antibiotics were prescribed for 24.2% (95% CI 18.9, 29.5) of patients with common colds and upper respiratory tract infections and for 42.2% (95% CI 35.2, 49.2) of patients with bronchitis. There were no significant associations between antibiotic use and patient race, sex, Hispanic ethnicity, geographic location, or source of payment. Antibiotics were prescribed less often by interns or residents than by staff or other physicians (odds ratio 0.43; 95% CI 0.19, 0.98), and patients younger than 18 years were less likely to receive antibiotics than adults (odds ratio 0.32; 95% CI 0.20, 0.52). Smokers were 4.3 (95% CI 2.2, 8.3) times more likely to receive antibiotics than nonsmokers. CONCLUSION: Antibiotics are commonly prescribed for ED patients with upper respiratory tract infections even though they are usually ineffective in otherwise healthy adults. Efforts should be made to reduce inappropriate antibiotic use for the sake of containing costs, preventing side effects, and limiting the spread of antibiotic resistance.

Adolescent↗

PubMed2003

Pulmonary function abnormality and respiratory tract irritation symptoms in epichlorohydrin-exposed workers in Taiwan.

BACKGROUND: Epichlorohydrin (ECH) is a strong irritant of the eyes, respiratory tract, and skin. The aims of this study were to examine the dose-response relationship between observed abnormal pulmonary function tests and respiratory tract irritation symptoms among epichlorohydrin-exposed workers in Taiwan. METHODS: A total of 167 workers were randomly selected from a resin synthesis factory. Sixty-six air samples were taken to determine ECH concentration in the workplace. Demographic data, work history, smoking status, and respiratory tract irritation symptoms were gathered by a standard self-administered questionnaire. Pulmonary function tests were also performed. RESULTS: There were 13 of 41 (31.7%) abnormal mean mid-expiratory flow (MMEF) among the high-ECH-exposed workers, 11 of 38 (29%) among the low-ECH-exposed workers, and 4 of 59 (6.8%) among non-ECH-exposed workers. There was a significant linear trend between ECH exposure and the prevalence of small airway abnormalities (P = 0.007) after adjusting for other factors. There was also a significant dose-response relationship of respiratory tract irritation symptoms (cough, phlegm, chest tightness, and dyspnea) among the ECH-exposed workers. CONCLUSIONS: This study suggests that obstructive lung abnormalities and small airway lung damage are associated with ECH exposure. The study also suggests that exposure to very low concentrations (<0.2 ppm) causes significant higher prevalence of respiratory tract irritation symptoms. Causal inferences from the findings cannot be made from this cross-sectional study and further longitudinal studies are needed to better clarify the nature of the observed associations.

Adult↗

PubMed2001

An acoustic model of the respiratory tract.

With the emerging use of tracheal sound analysis to detect and monitor respiratory tract changes such as those found in asthma and obstructive sleep apnea, there is a need to link the attributes of these easily measured sounds first to the underlying anatomy, and then to specific pathophysiology. To begin this process, we have developed a model of the acoustic properties of the entire respiratory tract (supraglottal plus subglottal airways) over the frequency range of tracheal sound measurements, 100 to 3000 Hz. The respiratory tract is represented by a transmission line acoustical analogy with varying cross sectional area, yielding walls, and dichotomous branching in the subglottal component. The model predicts the location in frequency of the natural acoustic resonances of components or the entire tract. Individually, the supra and subglottal portions of the model predict well the distinct locations of the spectral peaks (formants) from speech sounds such as /a/ as measured at the mouth and the trachea, respectively, in healthy subjects. When combining the supraglottic and subglottic portions to form a complete tract model, the predicted peak locations compare favorably with those of tracheal sounds measured during normal breathing. This modeling effort provides the first insights into the complex relationships between the spectral peaks of tracheal sounds and the underlying anatomy of the respiratory tract.

Acoustics↗

PubMedDate not supplied

Epidemiology of acute respiratory tract infections among young children in Kenya.

The epidemiology of acute respiratory tract infection (ARI) was investigated in a rural community 80 km north of Nairobi, Kenya. This research was conducted prospectively on 250 families with 470 children less than 5 years of age who were contacted every 8 days during the 3-year study. The yearly incidence of respiratory tract infections decreased from 5.2 to 3.4 during the study; less than 5% of these infections involved the lower respiratory tract. The incidence was inversely related to age, and the illnesses were generally mild and brief in length. Fifteen children died during the study period. The precise causes of death are unknown, but respiratory infections possibly played a role in most cases. This study emphasizes the importance of determining the risk factors responsible for unusually severe morbidity and high mortality in children with ARI in developing countries.

Acute Disease↗