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PubMed2001

An observational study on the epidemiology of respiratory tract bacterial pathogens and their susceptibility to four injectable beta-lactam antibiotics: piperacillin, piperacillin/tazobactam, ceftazidime and ceftriaxone.

Bacterial infections of the respiratory tract account for a large proportion of total medical consultations in general practice. In recent years, antibiotic resistance has increased alarmingly in a number of bacterial species that are common causes of these infections. The aim of this observational study was to determine the antibiotic resistance of microbial agents isolated from patients with acute or acutely exacerbated respiratory infections. Subjects recruited as potential sources of bacteria were either outpatients seen in a number of specialized clinics and hospital practices, or hospitalized patients. Overall, 648 consecutive patients (67% male, mean age 48.1+/-27.0 years) with infection of the upper or lower respiratory tract were observed during a 13-month period. A total of 551 pathogenic microbial strains were isolated and tested for their in vitro susceptibility to piperacillin, piperacillin/tazobactam, ceftazidime, and ceftriaxone. Among all isolates, the four most frequent pathogens were Pseudomonas aeruginosa (132 isolates, 24%), Streptococcus pyogenes (99 isolates, 18%), Staphylococcus aureus (93 isolates, 17%), and Klebsiella pneumoniae (46 isolates, 8%). The susceptibility of gram-positive isolates ranged from 97.5% to 95.1%, and no remarkable difference was found in the antibacterial activity of tested b-lactam antibiotics. The susceptibility of gram-negative isolates to piperacillin and piperacillin/tazobactam was also similar: 96.5% and 97.1%, respectively. In contrast, differences were found between piperacillin (or piperacillin/tazobactam) and either ceftazidime (p=0.003) or ceftriaxone (p<0.0003) in gram-negative isolates. We conclude that, despite the extensive use of beta-lactam antibiotics (piperacillin, ceftazidime, and ceftriaxone) in medical practice during the past three decades, the susceptibility of the most common pathogens involved in the etiology of upper and lower respiratory tract infections to these antibiotics is still high. In particular, bacterial resistance developed by gram-positive organisms against piperacillin is negligible and not alarming.

Adolescent↗

PubMed1996

Instrumentation and techniques in transendoscopic upper respiratory tract laser surgery.

Transendoscopic laser surgery provides equine surgeons with a safe, reliable, and minimally invasive method of performing many surgical procedures in the upper respiratory tract. Although the Nd:YAG laser has proven efficacy, other newer lasers such as the diode and holmium: YAG lasers may prove to be useful tools for equine upper respiratory tract surgery. Long grasping forceps and a high quality fiberoptic or video endoscope are critical components necessary for performing transendoscopic laser surgery. For many of the most common upper respiratory tract abnormalities, a laryngotomy can be eliminated, morbidity is minimal, the horse can often return to normal exercise in approximately 7 to 14 days, and trainer and owner acceptance is excellent. Transendoscopic laser surgery is most likely to be cost effective in large referral practices or in a university setting.

Animals↗

PubMed1999

Relationship between passive smoking, recurrent respiratory tract infections and otitis media in children.

UNLABELLED: The cause of upper respiratory tract infections (URTI) are multifactorial (enlarged adenoid, environmental conditions, staying at the care centers, smoking parents, allergy). Directly, viral infection causes damage to the ciliary cells and mucociliary clearance in the nasopharynx and Eustachian tube, promotes tubal occlusion and provokes otitis media. Enlarged adenoids reduce ventilation to the nasopharynx, increase accumulation of the secretion and provide a good condition for bacteria. AIMS OF THE STUDY: Evaluation of the factors playing a role in recurrent URTI and otitis media in children. Clinical and histopathological examination of adenoid tissue of children who were passive smokers and children who were not exposed to cigarette smoke. Evaluation of the difference between ciliary-mucous transport among passive smokers and children not exposed to cigarette smoke. METHODS: The analysis of interview questionnaires in 1000 children aged 3-14 years. Histopathological examinations of adenoid tissue excised in the group of children of recurrent upper respiratory tract infections and serous otitis media exposed and not exposed to cigarette smoke. CONCLUSIONS: Among the risk factors for URTI, the most important are: (1) socio-economic conditions; (2) staying at day care centers; and (3) passive smoking. Allergy was confirmed in 35-38% of URTI children. Surgical treatment was undertaken in 11.4-32.5% of URTI children (tonsilloadenoidectomy). Histopathological and ultrastructural evaluation of adenoid tissue in passive smoking children indicates significant differences to children not exposed to cigarette smoke.

Adenoids↗

PubMed1997

[The clinical manifestation and drug sensitive tests of lower respiratory tract infection by enterobacter cloacae. The Pulmonary Infection and Fibrosis Group, Thoracic Society Shanghai Medical Association].

OBJECTIVE: To study the clinical characteristics of lowar respiratory tract infection caused by E. cloacae and to investigate the drug sensitivities of E. cloacae strains. METHOD: (1) Analysing the clinical deta of 58 case with lowa respiratory tract infection of enterobacter cloacae defined by a putative standard, including ages, symptoms, signs, underlying diseases, sputum culture, X-ray findings and the prognosis. (2) Determining the drug sensitivities against the E. cloacae strains by K-B method. RESULTS: (1) There were 46 males and 12 females, with the mean age 56 +/- 19% cases diagnosed, who had underlying diseases, most were COPD. 41% cases were mixed infections with other bacteria, most of which were P. aeruginosa and K. pneumoniae. The chief symptoms were fever (72%) and productive cough (87%). The chest X-ray revealed inflammatory infiltration in lower lobes of both sides. The mortality rate was 9%. (2) The antimicrobial tests in vitro showed that these strains were multiresistant to antibiotics, but imipenem, amikacin, tobramycin, ciprofloxacin, cefoaperazone were sensitive. CONCLUSIONS: The lower respiratory tract infections caused by E. cloacae showed no specific clinical manifestations. However, the mortality was high. The diagnosis should be made according to bacteriologic examination combined with clinical and X-ray manifestations. Combining antibiotics therapy was recommanded according to antimicrobial sensitivity test.

Adult↗

PubMed1985

The emergence of resistance to beta-lactam antibiotics during treatment of Pseudomonas aeruginosa lower respiratory tract infections: is combination therapy the solution?

Treatment of Pseudomonas aeruginosa lower respiratory tract infections with beta-lactam antibiotics alone (beta-lactam monotherapy) has been thought to result in a high incidence of therapeutic failure due to the emergence of multiply-resistant strains on the basis of induction of a chromosomal beta-lactamase. Review of published experience in patients without granulocytopenia or cystic fibrosis suggests that favorable clinical responses can be obtained in 80-90% of cases, and bacteriological cures in 45-55%, using any of the newer beta-lactam antipseudomonal agents alone (data from cefsulodin, cefoperazone, azlocillin and piperacillin). Resistance develops in 30-40% of the infecting organisms, and is associated with treatment failure in 10-20% of cases (data from cefsulodin, ticarcillin and carbenicillin). Cross-resistance to other beta-lactams and to aminoglycosides can occur but seems unlikely to be on the basis of induction of a chromosomal beta-lactamase (data from cefsulodin). The addition of an aminoglycoside antibiotic (combination therapy) has been recommended to prevent these outcomes. Retrospective comparison with results obtained using combination therapy in patients without granulocytopenia or cystic fibrosis suggests that the addition of an aminoglycoside cannot be expected to prevent either the development of resistance or therapeutic failure (which are frequently unassociated). Treating every patient with a Pseudomonas aeruginosa lower respiratory tract infection with combination therapy will expose all of them to the toxicity of an aminoglycoside but will rarely repay this risk with the prevention of a multiply resistant strain or the salvage of a patient destined to fail beta-lactam monotherapy.

Aminoglycosides↗

PubMed1988

Degradation of host defenses against respiratory tract infection by Klebsiella pneumoniae in aged mice.

The host defense against respiratory tract infection with Klebsiella pneumoniae was much weaker in 60-week-old mice than in 4-week-old mice, but the resistance against systemic infection by intravenous and intraperitoneal challenge with K. pneumoniae in 60-week-old mice did not differ from that in 4-week-old mice. The number of alveolar macrophages at the resting stage in 60-week-old mice was the same as in 4-week-old mice, but the number of macrophages and polymorphonuclear leukocytes in the pulmonary cavity 4 h after challenge with formalinized K. pneumoniae in aerosol doubled in parallel with body weight. Phagocytosis and killing activities and superoxide anion production as measured by the Nitro Blue Tetrazolium reduction test of alveolar macrophages in 60-week-old mice were significantly weaker than in 4-week-old mice. The surfaces of the alveolar macrophages of the 60-week-old mice shrunk and a few adhered weekly to the glass plate, but the alveolar macrophages of the 4-week-old mice stretched to their full length and adhered firmly to the glass plate. These functions of alveolar macrophages clearly differed from those of peritoneal macrophages in 60-week-old mice, but those of the peritoneal phagocytes did not differ between 60-week-old and 4-week-old mice. The results suggest that the susceptibility to respiratory tract infection in 60-week-old mice is affected by a decline in the functions of alveolar macrophages rather than by the number of alveolar macrophages and exudated polymorphonuclear leukocytes in the lungs.

Aging↗

PubMed1998

[Investigation of the clinicopathologic features, immunophenotype and Epstein-Barr virus infection of the upper respiratory tract lymphomas in patients].

OBJECTIVE: To study the clinicopathologic features, immunophenotype and Epstein-Barr virus (EBV) infection of the upper respiratory tract lymphomas in patients from north China. METHODS: 112 cases of upper respiratory tract lymphomas in patients from north China were investigated. HE stain for histologic features. Immunohistochemistry studies were performed using monoclonal antibodies, UCHL-1 for T-lymphocyte, L26 and 4KB5 for B lymphocyte, CS1-4 for latent membrane protein-1 (LMP-1). In situ hybridization for EBV encoded small nuclear RNA (EBER 1/2, Y017, DAKO). RESULTS: 77/112 cases (68.75%) were T-cell lymphomas, 35 cases (31.25%) were B cell lymphomas. EBV-EBER 1/2 in situ hybridization positive in 54/101 (53.46%) cases, including 48 T-cell lymphoma cases and 6 B-cell lymphoma cases. CONCLUSION: Most upper respiratory tract lymphoma cases in patients from north China are T-cell lymphomas and are strongly associated with EBV.

Adolescent↗

PubMedDate not supplied

[Interobserver agreement in the radiological diagnosis of lower respiratory tract infections in children].

OBJECTIVE: To evaluate the inter-observer agreement of radiological diagnosis of lower respiratory tract infections in children. METHODS: Chest X-rays from 60 children younger than 5 years of age were evaluated by three physicians: a pediatric radiologist (PR), a pediatric pulmonologist (PP) and an experienced emergency pediatrician (EP). All children had sought an emergency room due to acute respiratory infections with apparent lower respiratory tract involvement. Observers were blinded to the original diagnostic conclusions, but clinical and laboratory data from the initial medical evaluation were provided with each film. Variables were grouped into five categories: a) film quality; b) site of abnormality; c) radiological patterns; d) other radiographic images; e) diagnosis. Inter-observer agreement was assessed using Kappa statistics, accepting prevalence-bias-adjusted values (PABAK). compare the prevalence of breastfeeding and exclusive breastfeeding during the first six months of life among pacifier and non-pacifier users. RESULTS: Kappa values for each of the three observer pairs (RP vs. PP, RP vs. EP, and PP vs. PE) were 0.41, 0.43, and 0.39, respectively. The overall inter-observer agreement was moderate (0.41). Agreement on other variables was as follows: regular for "film quality" (0.30); moderate for "site of abnormality" (0.48); fair for "radiological patterns" (0.29); moderate for "other radiographic images" (0,43); and moderate for "diagnosis" (0.33). The overall intra-observer agreement was "moderate" (0.54), which is below the agreement values reported by other studies on chest X-ray variability. CONCLUSIONS: Inter-observer variability is an intrinsic characteristic of the interpretation of chest X-rays, and the diagnosis of lower respiratory tract infections in children remains a challenge. Most of our results were similar to those previously reported.

Child, Preschool↗

PubMed1975

A theory of aerosol deposition in the human respiratory tract.

The deposition of inhaled aerosol particles in the human respiratory tract is due to the mechanisms of inertia impaction, Brownian diffusion, and gravitational settling. A theory is developed to predict the particle deposition and its distribution in human respiratory tract for any breathing condition. A convection-diffusion equation for the particle concentration with a loss term is used to describe the transport and deposition of particles. In this equation, an apparent diffusion coefficient due to the velocity dispersion in the lung is present and found to be the dominant diffusion mechanism for the cases considered here. Expressions for deposition by various mechanisms are also derived. The governing equation is solved numerically with Weibel's lung model A. The particle concentration at the mouth is calculated during washin and washout and compared favorably with experimental recordings for 0.5-mum diameter di(2-ethylhexyl) sebacate particles. The total deposition in the lung for particle size ranging from 0.05 to 5 mum is also computed for a 500-cm-3 tidal volume and 15 breaths/min. The results in general agree with recent measurements of Heyder et al. However, a particle size of minimum deposition is found to exist theoretically near 0.3 mum.

Aerosols↗

PubMed1996

Comparison of the effects of infectious bronchitis and infectious laryngotracheitis on the chicken respiratory tract.

In infectious bronchitis (IB) virus infection of the chicken the upper and lower respiratory tracts were damaged, but infectious laryngotracheitis (ILT) virus caused lesions only in the upper respiratory tract. Secondary infection with Escherichia coli was apparent in the trachea of birds inoculated with either virus but was more striking in those given IB virus. Serum alpha 1-acid glycoprotein, an acute-phase protein, occurred in higher concentrations in chickens inoculated with IB virus than in those given ILT virus.

Animals↗

PubMed2003

[Acute respiratory tract obstruction during thyroid operation: analysis of 10 cases].

OBJECTIVE: To explore the causes and management of acute respiratory tract obstruction in patients undergoing thyroid operation. METHODS: A retrospective review was conducted in 10 such cases that we encountered in our 11 years' experience with thyroid operation. RESULTS: Respiratory tract obstructions occurred in 10(0.31%) of 3,186 cases during thyroid operation. The causes for the obstructions included tracheomalacia in 2 cases, hematoma compression in 5 cases, trachea convulsion in 2 cases and phlegm obstruction in 1 case. Tracheotomy or intratracheal intubation was performed in 6 cases and hematoma removal in 4 cases, with the occurrence of death in 1 case. CONCLUSION: Hematoma compression and tracheomalacia etc. are among the most common causes of acute respiratory tract obstruction during thyroid operation, the occasion of which demands immediate implementation of tracheotomy or intratracheal intubation.

Acute Disease↗

PubMed1989

Assessment of clinical criteria for identification of severe acute lower respiratory tract infections in children.

222 acute lower respiratory tract infections (LRI), as defined by the World Health Organisation, were identified during one year's surveillance of a cohort of 500 Gambian children aged 0 to 4 years. Symptoms and signs at presentation were related to radiological evidence of lobar consolidation, indicating severe LRI. In infants, a fever of greater than 38.5 degrees C, refusal to breast-feed, or the presence of vomiting were the best predictors of severe LRI. In children aged 1 to 4 years, a fever of greater than 38.5 degrees C or a respiratory rate greater than 60/min were the most accurate clinical signs for severe LRI. Chest indrawing did not discriminate severe LRI. These community-based findings differ from results of hospital-based studies.

Acute Disease↗

PubMed1999

Clinical predictors of hypoxaemia in Gambian children with acute lower respiratory tract infection: prospective cohort study.

OBJECTIVES: To determine clinical correlates and outcome of hypoxaemia in children admitted to hospital with an acute lower respiratory tract infection. DESIGN: Prospective cohort study. SETTING: Paediatric wards of the Royal Victoria Hospital and the hospital of the Medical Research Council's hospital in Banjul, the Gambia. SUBJECTS: 1072 of 42 848 children, aged 2 to 33 months, who were enrolled in a randomised trial of a Haemophilus influenzae type b vaccine in the western region of the Gambia, and who were admitted with an acute lower respiratory tract infection to two of three hospitals. MAIN OUTCOME MEASURES: Prevalence of hypoxaemia, defined as an arterial oxygen saturation <90% recorded by pulse oximetry, and the relation between hypoxaemia and aetiological agents. RESULTS: 1072 children aged 2-33 months were enrolled. Sixty three (5.9%) had an arterial oxygen saturation <90%. A logistic regression model showed that cyanosis, a rapid respiratory rate, grunting, head nodding, an absence of a history of fever, and no spontaneous movement during examination were the best independent predictors of hypoxaemia. The presence of an inability to cry, head nodding, or a respiratory rate >/= 90 breaths/min formed the best predictors of hypoxaemia (sensitivity 70%, specificity 79%). Hypoxaemic children were five times more likely to die than non-hypoxaemic children. The presence of malaria parasitaemia had no effect on the prevalence of hypoxaemia or on its association with respiratory rate. CONCLUSION: In children with an acute lower respiratory tract infection, simple physical signs that require minimal expertise to recognise can be used to determine oxygen therapy and to aid in screening for referral. The association between hypoxaemia and death highlights the need for early recognition of the condition and the potential benefit of treatment.

Acute Disease↗

PubMed1977

Demonstration of cross-reacting tumor rejection antigens in chemically induced respiratory tract carcinomas in rats.

Experiments were performed to determine whether chemically induced rat respiratory tract carcinomas, which possess considerable immunogenicity, contain cross-reacting antigens. In vivo studies showed that effective cross-protection can be induced with four of the five respiratory tract cancers studied, suggesting that these tumors have common tumor rejection antigens. In vitro cytotoxicity studies with sera from tumor-immune hosts showed cross-reactivity among three of the carcinomas tested.

9,10-Dimethyl-1,2-benzanthracene↗

PubMedDate not supplied

[Primary melanoma of the respiratory tract].

4 cases of melanoma of the respiratory tract (trachea and bronchi) are analysed clinico-morphologically. A case of melanoma with a primary multiple location (trachea and the main bronchus), rapid recurrence after surgery and radiation therapy is described in detail. Melanocytic nature of the tumor is proved immunohistochemically.

Adult↗

PubMed1985

[Problem discussion of allergic reactions in patients with infection-induced bronchial asthma in Candida colonization outside the respiratory tract].

Candida albicans colonization outside from the respiratory tract can occur as a side-effect of long lasting antibiotica therapy in patients with infection-induced asthma bronchiale and may induce in them allergic reactions. Based on own experiences the author reports on the frequency of Candida infections following antibiotica therapy and the effect of a therapy with Fungicidin on the number of dyspnoe attacks.

Anti-Bacterial Agents↗

PubMed1989

[Susceptibility of bacteria isolated from patients with lower respiratory tract infections to antibiotics (1986)].

Enlisting the help of various research institutions across the nation, Ikemoto et al. have been pooling cultures of clinical isolates of respiratory tract infections and mapping out the correlations between patient backgrounds and the causative bacteria and the changes in the sensitivity spectra of the bacteria to various antibacterial and antibiotic agents annually since 1981. The following is a report of the 1986 findings. During the period from September, 1986 to March, 1987, 558 cases of respiratory infections were reported at 17 institutions across the nation and a total of 657 apparent causative strains were isolated from sputum samples. Of these strains, 75 strains of Staphylococcus aureus, 108 of Streptococcus pneumoniae, 150 of Haemophilus influenzae, 107 of Pseudomonas aeruiginosa (non-mucoid production type), 21 of P. aeruginosa (mucoid production type), 32 of Klebsiella pneumoniae, 8 of Escherichia coli, and 55 of Branhamella catarrhalis were subjected to MIC determination of various antibacterial and antibiotic agents to map drug sensitivities. In addition, diagnoses, age distributions by diagnoses, frequencies of infectious diseases, types of isolated bacteria, and usage statuses of the antibacterial and antibiotic agents the times of at isolation were also investigated. MIC determinations were carried out to investigate susceptibilities of causative organisms of respiratory tract infections to various antibacterial and antibiotic agents. From the 558 cases of respiratory tract infections, 657 strains were detected at concentrations not less than 10(4-6)/ml and identified to be the causative organisms. Of these strains, 603 could be used for MIC determination. An overwhelming majority of major causative bacteria, inclusive of H. influenzae and S. pneumoniae, showed sensitivity patterns similar to the sensitivity patterns found a year earlier, P. aeruginosa alone, however, showed some increase in its susceptibility to penicillin and cephem antibiotics. Regarding patient backgrounds, the age distribution was heavily biased towards the higher end of the scale, which patients with ages of 50 or higher accounting for 77.9%, compared to 73.5% in 1985. When the patients were classified by diagnoses, chronic bronchitis, bacterial pneumonia and bronchiectasis accounted for the majority of the infections: 28.7%, 23.3%, and 19.0%, respectively. The percentages of chronic bronchitis and bacterial pneumonia 28.7% and 23.3%, respectively, were somewhat higher in 1986 than in 1985. The disease which was comparatively frequent in all age groups was bronchiectasis, which accounted for 44.0% in patients with ages 29 years or lower, 18.4% in patients between 30 years and 69 years, and 16.7% in patients with ages 70 years or higher. The next most frequent infection was bacterial pneumonia.(ABSTRACT TRUNCATED AT 400 WORDS)

Anti-Bacterial Agents↗

PubMed1998

[Hypersensitivity to house dust mites and incidence of acute respiratory tract infections in children with bronchial asthma].

The aim of the study was to evaluate the relationship between h.d.m. allergy and incidence of respiratory tract infections in children with episodic, mild and moderate asthma. 32 children with bronchial asthma being followed up at the I. Department of Children Diseases P.A.I.P. CMUJ in Cracow were included into the study. The positive skin prick test (SPT) with H.D.M. allergens was confirmed in 18 children. The negative SPT allergens were observed in 14 patients. All patients were examinated by the retrospective inquiry which included the degree of asthma, severity of therapy schedule and incidence of acute respiratory tract infections during the last 6 months. The anthropometric measurement (length, weight, body mass index, thorax circumference) and spirometric parameters with physical examination challenge were introduced. The mean number of infections in group of patients sensitive to H.D.M. was 6.8; in non sensitive group-4.6. There was no significant difference in incidence of acute respiratory tract infections between both groups. It seems likely that small number of patients may influence the statistics. To verify the results, prospective observation of wider group of patients is planned in forthcoming winter.

Animals↗