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PubMed1999

[Laboratory and clinical investigation on lower respiratory tract infection by Haemophilus influenzae].

OBJECTIVE: To improve the positive rate of Hi isolation and to study the epidemiology, antibiotic sensitivity and clinical characteristics of the lower respiratory tract infection by Hi. METHODS: Modified Columbia chocolate agar(ICCA) was compared with blood agar staphy stick (BASS) for the primary isolation of Hi from sputa. The sensitivities of 20 antibiotics to Hi were determined in vitro by KB method and MICs of 12 antibiotics were determined by broth microdilution method. The clinical characteristics of 92 cases with lower respiratory tract infection by Hi were analyzed. RESULTS: The isolation rate of Hi by ICCA was 20%, which was higher than 13% of BASS(P < 0.01). The third generation cephalosporins and the quinolones were most active against Hi. The resistant rate against Hi of ampicillin was 21%, however, that of the third generation cephalosporins was 45%-49%. 67(73%) of 92 cases were bronchopneumonia. CONCLUSIONS: The isolation rate of Hi could be improved by ICCA. The clinical characteristic of lower respiratory tract infection by Hi was not specific. There has been a steady increase of antibiotic resistance during these years.

Adolescent↗

PubMed1996

Increased exhaled nitric oxide in asthma is mainly derived from the lower respiratory tract.

Nitric oxide (NO) is detectable in the exhaled air of human subjects, and its concentration is increased in patients with asthma. We have investigated the origin of the increase in exhaled NO in asthmatic patients by using different expiratory maneuvers and by direct sampling from the upper and lower respiratory tracts. Exhaled NO was measured by a chemiluminescence analyzer. Concentrations of NO measured during expiration against the resistance of the analyzer with exhaled flow of 1 L/min, were 78 +/- 3 ppb in normal subjects (n = 46) and significantly elevated in patients with asthma (301 +/- 26 ppb, n = 30, p < 0.001). Values of exhaled NO were lower when measured during unobstructed expiration with a flow of 5 L/min with sampling from a side-arm (7 +/- 1 ppb), but again were elevated in patients with asthma (46 +/- 6 ppb, p < 0.001). Breath-holding for 20 s resulted in an initial peak of NO, but end-expiration values similar to the unobstructed expiration. The concentration of NO in the nose was considerably greater than in expired air (996 +/- 39 ppb) and was elevated in patients with asthma (1,390 +/- 71 ppb, p < 0.002). Direct sampling from trachea and right middle lobe bronchus via a fiberoptic bronchoscope gave similar values in five normal and 15 asthmatic subjects to the values recorded during unobstructed expiration, and there was a good correlation between values in expired air and direct sampling (trachea r = 0.91, right middle lobe r = 0.87, p < 0.001). We conclude that exhaled NO measured in an unobstructed breath reflects concentrations in the lower respiratory tract, but that breath-holding or expiration against resistance is contaminated by residual NO derived from the upper respiratory tract. We also provide evidence that the elevated levels of exhaled NO in asthmatic patients are derived predominantly from the lower respiratory tract.

Adult↗

PubMed2002

Anaerobic bacteria in upper respiratory tract and other head and neck infections.

Anaerobic bacteria are common in chronic upper respiratory tract and head and neck infections. Anaerobes are the most predominant components of the normal human oropharyngeal bacterial flora, and are therefore a common cause of bacterial infections of the upper respiratory tract that are of endogenous origin. Because of their fastidious nature, anaerobes are difficult to isolate from infectious sites and are often overlooked. Anaerobic bacteria can be recovered in chronic otitis media and sinusitis, and play a role in tonsillitis. They are also important in complications of these infections. Anaerobes predominate in deep oral and neck infections and abscesses. In addition to their direct pathogenicity in these infections, they possess an indirect role through their ability to produce the enzyme beta-lactamase. In this fashion, they are capable of "shielding" non-beta-lactamase-producing bacteria from penicillins. The lack of directing adequate therapy against these organisms may lead to clinical failures. Their isolation requires appropriate methods of collection, transportation, and cultivation of specimens. Treatment of anaerobic infections is complicated by the slow growth of these organisms, by their polymicrobial nature, and by the growing resistance of anaerobic bacteria to antimicrobials. Antimicrobial therapy is often the only form of therapy required, whereas in other cases, it is an important adjunct to a surgical approach. Because anaerobic bacteria generally are recovered mixed with aerobic organisms, the choice of appropriate antimicrobial agents should provide for adequate coverage of both types of pathogens.

Anti-Bacterial Agents↗

PubMed1984

Neuropeptide tyrosine (NPY): a newly discovered peptide is present in the mammalian respiratory tract.

Neuropeptide tyrosine (NPY), a newly discovered peptide known to modulate blood vessel diameter and smooth muscle tone, has been found in many mammalian organs. Its distribution is similar to that of sympathetic nerve fibres and NPY immunoreactivity has been found in noradrenergic ganglion cells. In a study of the respiratory tract of four mammalian species--man, cat, guinea pig, and rat--NPY immunoreactivity has been localised to nerve fibres. NPY immunoreactive nerve fibres were found in the adventitia of blood vessels and in the airway smooth muscle. Its distribution was strikingly similar to that of sympathetic nerve fibres as demonstrated by dopamine-beta-hydroxylase antibodies. The mean (SD) concentrations of NPY in the guinea pig respiratory tract, as determined by radioimmunoassay of tissue extracts, were: upper trachea 3.3 (0.7), lower trachea 2.0 (0.5), and major bronchus 3.5 (1.1) pmol/g. During developmental studies in man NPY immunoreactive nerve fibres were first observed at 20 weeks' gestation in the trachea, and fibres gradually extended down into the intrapulmonary airways after birth. NPY immunoreactive nerve fibres have a distribution and developmental pattern similar to that of sympathetic nerve fibres in the respiratory tract. The finding of NPY immunoreactivity in nerve fibres in the mammalian respiratory tract adds to the growing number of peptides having potent biological actions found in this organ, and shows that the lung possesses a rich peptidergic system, which may influence pulmonary function.

Adolescent↗

PubMed1981

[Prophylaxis and treatment of respiratory tract infection in ventilated patients by endotracheal administration of aminoglycosides (author's transl)].

The effects of intratracheal administration of gentamicin on frequency of bacterial contamination of the trachea and respiratory tract infection were assessed in a controlled and prospective study in 20 patients on a respirator. Gentamicin was instilled undiluted 6-hourly in a dosage of 40 mg into the trachea. Compared with a control group (n = 20), patients with intratracheal gentamicin instillation showed earlier reduction of tracheal bacterial contamination and during further ventilation a diminished rate of colonisation of the trachea. There was no evidence of an increase of Candida albicans. Pneumonic infiltrations regressed earlier in patients with intratracheal gentamicin. Respiratory tract infections were less frequent during continued artificial ventilation than in the control group. In ventilated patients intratracheal aminoglycosides can thus be recommended for prophylaxis of respiratory tract infections.

Female↗

PubMed2005

The use of antibiotics for viral upper respiratory tract infections: an analysis of nurse practitioner and physician prescribing practices in ambulatory care, 1997-2001.

PURPOSE: There are extensive data that describe the prescriptive behaviors of physicians (MDs) for upper respiratory tract infections; however, there is a paucity of data on the antibiotic-prescribing patterns of nurse practitioners (NPs). The purpose of this study was to describe and predict factors that are associated with antibiotic prescribing by NPs and MDs for viral upper respiratory infections in the ambulatory setting. DATA SOURCES: The study utilized a cross-sectional retrospective design of data from the National Hospital Ambulatory Medical Care Survey and the National Ambulatory Medical Care Survey between 1997 and 2001. Data were collected on a national probability sample of 506 NP and 13,692 MD visits for patients with nonspecific upper respiratory tract infection, viral pharyngitis, and bronchitis. CONCLUSIONS: Bivariate analysis found no significant differences in antibiotic prescribing for viral upper respiratory tract infections by NPs (50.4%) and MDs (53%). Broad-spectrum antibiotics accounted for 36.6% of the NP antibiotic prescriptions and for 33.2% of the MD antibiotic prescriptions. Multivariate analysis identified several clinical and nonclinical factors that are associated with NP antibiotic prescribing. The strongest positive predictors of NP antibiotic prescribing were black race, Medicaid insurance, Northeast region, and diagnoses of viral pharyngitis and bronchitis. The significant negative predictor was Medicaid insurance status. The strongest positive predictors of MD prescribing were viral pharyngitis, bronchitis, and non-antibiotic prescription. IMPLICATION FOR PRACTICE: The excessive use of antibiotics for upper respiratory infections of viral etiology by both NPs and MDs suggests the continuing need for educational initiatives such as "academic detailing" as well as increasing involvement by both groups of providers in the dissemination of clinical guidelines and system-based quality assurance programs. Also, the lower rate of antibiotic prescribing for viral infections by NPs for patients with Medicaid insurance suggests more appropriate cost-effective care in this population of patients. More study is needed in general on prescribing by NPs for Medicaid patients. Finally, the strong association of nonclinical factors suggests the need for awareness and improvement of prescribing decisions by both NPs and MDs.

Adolescent↗

PubMed2004

Antimicrobial susceptibility of respiratory Haemophilus influenzae strains isolated from pediatric respiratory tract infections.

BACKGROUND: Haemophilus influenzae (H. influenzae) is the most frequent bacterial pathogen of respiratory tract infections in children. Detection of antimicrobial susceptibility of H. influenzae is necessary for institution of appropriate antibiotic treatments. METHODS: A total of 281 strains of H. influenzae isolated from sputum samples of 281 pediatric patients with respiratory tract infections were recruited for study. Antibiotic susceptibility was determined by assessing minimum inhibitory concentrations (MIC) of antimicrobial agents. MIC were measured by utility of Agar dilution susceptibility test. RESULTS: Of the total, 38 (13.5%) strains produced beta-lactamase (BLP), 56 (19.9%) strains were beta-lactamase non-producing, ampicillin resistant (BLNAR). The overall resistant proportion to ampicillin was 33.4%. The data indicated that sulbactam/ampicillin, cefotaxime, ceftriaxone and cefditoren are effective against BLP strains. In addition, a high prevalence of BLNAR H. influenzae strains was identified, with an overall isolation rate of 19.9%. Those strains mainly demonstrated intermediate level to ampicillin (ampicillin-MIC </= 3.13 micro g/mL for most of BLNAR strains). However, antimicrobial activities of cefotaxime, ceftriaxone and cefditoren against those strains were slightly diminished. Recovery rate of BLP strains was varied by years, peaking at 19.5%. In particular, a trend of yearly increase in frequency of BLNAR strains was observed. CONCLUSION: Frequency of BLNAR strains causing respiratory infections has been dramatically increasing, which can diminish antibiotic activities of not only ampicillin but also of some cephems.

Amoxicillin↗

PubMed1997

Comparative clastogenic sensitivity of respiratory tract cells to gamma rays.

To understand the relationships between exposure and damage to different cell populations in the respiratory tract, methods were developed to culture deep-lung fibroblasts and epithelial cells from the nose, trachea and deep lungs. Female F-344 Fischer and male Wistar rats were exposed to 1-5 Gy of 60Co gamma rays at a dose rate of 0.4 Gy/min. Cells were isolated for short-term culture, and the incidences of binucleated cells and micronuclei were determined. The incidences of micronuclei were determined in cytochalasin-B-induced binucleated cells at 72 h for nasal and tracheal tissue and 96 h for deep-lung fibroblasts and epithelial cells. Maximum frequencies of binucleated cells were found in the control nonirradiated cells at these harvest times, and the frequencies were not significantly affected at these harvest times by radiation exposure. No significant differences were found in the frequencies of micronuclei induced in the nasal epithelial cells isolated from female F-344 Fischer or male Wistar rats. Fibroblasts cultured in different media and isolated from either female F-344 Fischer or male Wistar rats also showed a similar frequency of micronuclei. Over the doses tested, the frequency of micronuclei in the respiratory tract cells increased linearly with the dose. The slopes were 92.2 +/- 9.2, 76.2 +/- 7.9, 32.8 +/- 2.4 and 28.7 +/- 3.4 micronuclei/1000 binucleated cells/Gy for deep-lung epithelial cells, deep-lung fibroblasts, tracheal epithelial cells and nasal epithelial cells, respectively. Deep-lung epithelial or fibroblast cells were about two to three times as sensitive for elastogenic damage as nasal and tracheal epithelial cells. The measurement of micronuclei in isolated respiratory tract cells is very useful in assessing cytogenetic damage induced in different cell types by radiation.

Animals↗

PubMed1985

[Cefaclor in the treatment of respiratory tract infections in children].

61 children up to the age of 14 years with respiratory tract infections underwent therapy with Cefaclor. 52 patients (89%) had satisfactory results. 4 patients (7%) experienced prolonged signs of infection. Cefaclor was very well tolerated. Because of its wide spectrum of activity particularly against ampicillin resistant strains of H. influenzae and because of its good tolerance Cefaclor is very useful in treatment of respiratory tract infections in children.

Adolescent↗

PubMed2003

In vitro activity of ertapenem against anaerobes isolated from the respiratory tract.

Ertapenem is a novel parenteral carbapenem with a long serum half-life. Its spectrum of activity is similar to that of imipenem and meropenem against Gram-positive bacteria, Enterobacteriaceae and fastidious Gram-negative bacteria but it is less active against Pseudomonas aeruginosa and Acinetobacter spp. Several studies were performed in the United States but only one European study has shown that ertapenem has an excellent activity against anaerobes. The objectives of the present study were to test the activity of ertapenem against anaerobes isolated prospectively from the lower and upper respiratory tracts, and to compare their susceptibility with that of anaerobic isolates from other body sites. Fifty-three isolates from the respiratory tract, as well as 50 isolates from various other body sites were tested with E-tests against six antibiotics. For respiratory isolates and for isolates from other sites, MIC 90 values (mg/l) were, respectively, >32 and >32 for penicillin, 0.38 and 0.75 for amoxicillin/clavulanate, 48 and >256 for ceftriaxone, 0.12 and 0.75 for ertapenem, 12 and >256 for clindamycin and 2 and 12 for moxifloxacin. The higher susceptibility of respiratory tract isolates was mainly due to the different distribution of isolated species: only three respiratory isolates but 22 other isolates belonged to the Bacteroides fragilis group. This study confirms the excellent anti-anaerobic activity of ertapenem against anaerobic isolates from the respiratory tract.

Bacteria, Anaerobic↗

PubMed1995

[Clinical efficacy of sulbactam/cefoperazone for the treatment of geriatric patients with respiratory tract infections].

We performed clinical studies on sulbactam/cefoperazone (SBT/CPZ) for the treatment of geriatric patients with respiratory tract infections. Seven patients with pneumonia, 7 with acute bronchitis, 6 with chronic respiratory tract infections were treated with SBT/CPZ. The patients were administered with a daily dose of 2.0 g or 4.0 g for 4-14 days. The clinical responses were excellent in 3, good in 13, fair in 3, and poor in 1 patients. The efficacy rate was 80.0%. No side effects were observed in any patients, but elevations of GOT, GPT were observed in two cases. Causative organisms were E. coli (2 strains), P. aeruginosa (2), MSSA (1), MRSA (1), S. pneumoniae (1), H. influenzae (1), K. oxytoca (1), and E. aerogenes (1). The bacteriological effect rate was 60%. One strain of MRSA and one of two strains of P. aeruginosa persisted in 2 patients.

Aged↗

PubMed1991

Activity of temafloxacin and other fluoroquinolones against typical and atypical community-acquired respiratory tract pathogens.

The microbiologic activities of temafloxacin, ciprofloxacin, and ofloxacin against community-acquired respiratory tract pathogens are reviewed. The 90% minimal inhibitory concentrations (MIC90s) of these fluoroquinolones for gram-negative pathogens were generally comparable, that is, less than 0.06 micrograms/mL. Overall, the agents were less active against gram-positive pathogens, although temafloxacin was two- to fourfold more active than the other agents against staphylococci and streptococci. For strains of Mycoplasma pneumoniae and Chlamydia pneumoniae, temafloxacin was generally inhibitory at concentrations of 0.5-2 micrograms/mL. This microbiologic activity, combined with its pharmacokinetic profile, should make temafloxacin a useful antimicrobial agent for treating community-acquired respiratory tract infections.

Anti-Infective Agents↗

PubMed1987

Maternal smoking during pregnancy and lower respiratory tract illness in early life.

In a national study of 12,743 children maternal, but not paternal, smoking was confirmed as having a significant influence on the reported incidence of bronchitis and admission to hospital for lower respiratory tract illness during the first five years of life. Reported rates of admissions to hospital for lower respiratory tract diseases were found to be as high in children born to mothers who stopped smoking during pregnancy as in those whose mothers smoked continuously both during and after pregnancy. Rates of admissions to hospital for lower respiratory tract diseases in children whose mothers started smoking only postnatally were no higher than in those whose mothers remained non-smokers. Postnatal smoking seemed to exert a significant influence on the reported incidence of bronchitis, but less than smoking during pregnancy. These findings suggest that maternal smoking influences the incidence of respiratory illnesses in children mainly through a congenital effect, and only to a lesser extent through passive exposure after birth.

Child, Preschool↗

PubMed2000

Wegener's granulomatosis in the upper respiratory tract.

Wegener's granulomatosis is a distinct clinico-pathological entity characterised by necrotising vasculitis of small arteries and veins in conjunction with the formation of granuloma in the upper and lower respiratory tracts, and glomerulonephritis. The vast majority of patients have antineutrophil cytoplasmic antibodies in the serum with a characteristic cytoplasmic pattern. However, in early phases of the disease only the upper respiratory tract may be affected, clinical and histological features may be nonspecific, and antineutrophil cytoplasmic antibodies not present. In this paper we present four patients with involvement of the upper respiratory tract suspicious for early Wegener's granulomatosis. We emphasise the significance of clinical, histological and serological parameters in the early detection of Wegener's granulomatosis.

Aged↗

PubMed1990

V factor-dependent members of the family Pasteurellaceae in the porcine upper respiratory tract.

A study was performed to obtain a better understanding of the diversity and ecology of members of the family Pasteurellaceae in the porcine respiratory tract. A collection of 132 V factor-dependent strains of Pasteurellaceae selected from porcine field isolates mainly from the respiratory tract were subjected to detailed characterization. In addition to the three hitherto recognized species Actinobacillus pleuropneumoniae, Haemophilus parasuis, and Haemophilus taxon "minor group," three distinct taxa were observed. Some of these taxa, which are provisionally designated taxa D, E, and F, would by traditional criteria be mistaken for H. parasuis but differed by several biochemical characteristics. To study the ecology of the V factor-dependent species, swabs from the nasal and oral cavities of 29 pigs were cultivated on selective and nonselective media. By studying approximately 30 isolates from each sample, the distribution and relative proportion of the individual taxa were determined. A. pleuropneumoniae was detected in samples from the tonsil areas of only two acutely ill animals. H. parasuis was isolated from the nasal cavities of four out of nine healthy pigs but from the oral cavities of only two animals. In contrast, taxon "minor group" and taxa D, E, and F were present in the oral cavities of the majority of pigs but were not detected in samples from their nasal cavities. The results indicate that all the observed V factor-dependent species of Pasteurellaceae except A. pleuropneumoniae, are members of the resident microflora of various mucosal surfaces of the porcine upper respiratory tract.

Animals↗

PubMed1983

Clinical evaluation of cefotetan in the treatment of lower respiratory tract infections.

Cefotetan, a new cephamycin antibiotic, was evaluated for the treatment of lower respiratory tract infections. Intravenous cefotetan (2 g every 12 h) was administered for 4 to 8 days (mean, 5.8 days) to 56 hospitalized adult patients. Of the 41 evaluable patients, the clinical response was satisfactory in 38 (93%) and the bacteriological response was satisfactory in 36 (88%). The drug was well tolerated, and there were minimal complaints or changes in clinical laboratory values. From these preliminary results, cefotetan appears to be safe and effective for the treatment of lower respiratory tract infections.

Adult↗

PubMed1990

Persistent lower respiratory tract inflammation associated with interstitial lung disease in patients with tropical pulmonary eosinophilia following conventional treatment with diethylcarbamazine.

Tropical pulmonary eosinophilia (TPE) presents as an acute syndrome with dyspnea, fluffy infiltrates, and rounded opacities on the chest radiograph, reduced lung function, marked eosinophilia in the blood and lower respiratory tract, and high titers of specific IgE and IgG antifilarial antibodies. The standard therapy for TPE is a 3-wk course of diethylcarbamazine (DEC) following which there is almost always a marked improvement in all parameters. However, clinical observations suggest that the disease can persist despite DEC therapy and lead to chronic dyspnea with restrictive lung impairment. To evaluate the concept that DEC therapy is not completely "curative" for TPE, but rather leaves most individuals with a mild, chronic form of TPE defined by persistent inflammation of the lower respiratory tract, we evaluated 23 individuals an average of 12 +/- 2 months following a standard 3-wk course of diethylcarbamazine for acute TPE. In the majority there were mild, persistent symptoms referrable to the lung, chest X-ray abnormalities, blood eosinophilia, and elevated serum IgE and filarial specific IgG. On the average, lung function was consistent with the presence of chronic, mild interstitial lung disease. When the inflammatory cells from the lower respiratory tract were examined, there was a persistent eosinophilic alveolitis (TPE/post-DEC 1769 +/- 376 eosinophils/microliters epithelial lining fluid; normal subjects 256 +/- 38, p less than 0.02). Evaluation of the lower respiratory tract inflammatory cells recovered from the TPE/post-DEC-treated individuals demonstrated spontaneous release of exaggerated amounts of O2-. and H2O2 compared to normal subjects (p less than 0.05, both comparisons).(ABSTRACT TRUNCATED AT 250 WORDS)

Acute Disease↗

PubMed1980

The immunologic response to group A streptococcal upper respiratory tract infections in very young children.

The immunologic responses to streptolysin O and streptococcal deoxyribonuclease B were evaluated in children with group A streptococci recovered from the upper respiratory tract to re-examine the hypothesis that a limited capacity to respond to group A streptococcal infection may explain the rare occurrence of acute rheumatic fever in very young children. ASO and anti-DNase B titers were determined on serial bleedings from a total of 301 individuals (52 less than or equal to 3 years; 249 older than 3 years). Very young children with group A streptococcal upper respiratory tract infections had an immunologic response to SO greater than the response in older children as reflected by the magnitude of the antibody rise, and comparable to the ASO response in older children as measured by the percentage showing a significant titer rise. Similar analyses of the anti-DNase B responses showed the response in young children to be comparable to those of the older group. Clinical manifestations of group A streptococcal upper respiratory tract infection in very young children differ from those observed in older children and have not changed significantly in the past several decades. These data suggest that the infrequent occurrence of acute rheumatic fever in very young children is not due to a difference in antibody response to streptolysin O or streptococcal DNase B.

Adolescent↗