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PubMed1988

Comparative, multicenter studies of cefixime and amoxicillin in the treatment of respiratory tract infections.

A total of 560 patients were treated in two double-blind, randomized multicenter studies to compare the safety and efficacy of cefixime (400 mg administered once daily) and amoxicillin (250 or 500 mg administered three times daily) for the treatment of bacterial respiratory tract infections. Eighty percent of the 244 patients treated in the lower respiratory tract infections (LRTI) study had acute bronchitis. Streptococcus pneumoniae (13 percent), Haemophilus influenzae (28 percent), and Escherichia coli (10 percent) were the pathogens most frequently isolated from sputum in these patients. Among evaluable patients with positive bacterial culture results at baseline, a favorable clinical response (cured or improved) was obtained in 100 percent of the cefixime-treated patients (22 of 22) and in 96 percent of the amoxicillin-treated patients (23 of 24). Bacteriologic eradication rates were 100 percent and 83 percent for cefixime and amoxicillin, respectively. In the upper respiratory tract infections (URTI) study, 316 patients with pharyngitis (80 percent) or tonsillitis (14 percent) were treated. Group A, beta-hemolytic Streptococcus (69 percent) and H. influenzae (8 percent) were the pathogens most frequently isolated from the throat culture specimens of these patients. Favorable clinical results were obtained in 99 percent of the evaluable cefixime-treated group (n = 73) and in 98 percent of the amoxicillin-treated group (n = 66). The bacteriologic eradication rates were 93 percent and 100 percent, respectively. The adverse experiences reported during both studies were similar in nature and frequency to those reported for other beta-lactam antibiotics with the exception of a higher incidence of altered bowel movement (diarrhea and stool changes) with both drugs. These episodes usually resolved without remedial medication when the treatment was withdrawn. No significant adverse laboratory findings were observed. Results of these trials demonstrate that cefixime at a dosage of 400 mg once daily is an effective and safe oral antibiotic for the treatment of acute respiratory tract infections.

Amoxicillin↗

PubMed1987

[Susceptibility of bacteria isolated from the patients with lower respiratory tract infections to antibiotics (1985)].

It has been more than 4 years since third-generation cephems were introduced into clinical practice. The range of our drug selection definitely tends to increase, because we today have more antibiotics with wider spectrum, antibiotics with strong activities only against Gram-negative strains, such as monobactams, and those with tremendously high activities such as quinolone carboxylic acid derivatives, in comparison to those we had in the past. Among isolates obtained mainly from sputa of 567 patients with lower respiratory tract infections at 16 institutions throughout Japan between September of 1985 and March of 1986, 741 strains were determined to be causative organisms. MIC's of various antimicrobial agents were determined against 67 strains of Staphylococcus aureus, 100 strains of Streptococcus pneumoniae, 199 strains of Haemophilus influenzae, 92 strains of non-mucoid Pseudomonas aeruginosa, 40 strains of mucoid P. aeruginosa, 29 strains of Klebsiella pneumoniae, 10 strains of Escherichia coli and for 42 strains of Branhamella catarrhalis out of the above 741 strains to determine their drug sensitivities. As for types of lower respiratory tract infections found in 1981--1983, 57.9--64.5% of the infections were chronic respiratory infections; i.e., chronic bronchitis, chronic bronchiolitis and bronchiectasis. These chronic infections, including diffuse panbronchiolitis (DPB), were found in 63.1% of lower respiratory tract infections in 1984. Their incidence dropped to 54.0% in 1985, even though DPB was included; i.e., the incidence of chronic bronchiolitis was 5.5%, that of DPB was 7.1%, and that of bronchial asthma associated with lower respiratory tract infections in 1985 was 8.8% which was twice as much as that found in 1981--1984. Although bacterial pneumonia was found in 24.8% of all the cases in 1981, its incidence was reduced to 11.0% in 1983, 15.1% in 1984, and 17.6% in 1985. This reduction seemed to have resulted from gradual decreases in the occurrence of bacterial pneumonia among the young population. As with usual years, a high incidence rate in a total lower respiratory tract infections in 1985 was found among older patients; namely, 73.5% was at the age of 50 or over (417/567). Next, we determined relationships between clinical isolates and isolates from respiratory infections, including chronic bronchitis, chronic bronchiolitis, bronchiectasis and DPB. H. influenzae was isolated from 50.5% of patients with these infections in 1981; however, the detection rate decreased by about 20% to 29.7% in 1985. P. aeruginosa was consistently isolated, between 24.1% and 30.4% every year.(ABSTRACT TRUNCATED AT 400 WORDS)

Adult↗

PubMed1984

Modifying effect of vitamin A on benzo[a]pyrene-induced respiratory tract tumours in hamsters.

Groups of 40 hamsters of each sex were fed natural ingredient diets containing 600, 4000 or 100 000 IU vitamin A/kg. After an adaptation period of 170 days on the diets, respiratory tract tumours were induced by intratracheal instillation of benzo[a]pyrene + ferric oxide suspended in saline. Mortality was statistically significantly increased in the high dose group as compared with the mid (control) and low dose group. Microscopy of the respiratory tract did not reveal any significant differences in tumour response between the various dose groups. However, the incidence of preneoplastic respiratory tract lesions was distinctly inversely correlated with the oral vitamin A dose. The serum retinol values were similar in the various dose groups, without any indication of a dose related increase. It was concluded that under the experimental conditions used vitamin A did not influence benzo[a]pyrene-induced respiratory tract cancer in hamsters.

Animals↗

PubMed2006

[Detection of etiologic agents and antibiotic resistance in children with acute lower respiratory tract infection in Wenzhou City].

OBJECTIVE: The etiology of acute lower respiratory tract infection (LRTI) in children in Wenzhou City remains poorly defined. This study investigated the etiological agents responsible for acute LRTI and patterns of the antibiotic resistant bacterial pathogens in children with acute LRTI from Wenzhou City. METHODS: Lower respiratory tract secretions were obtained from 454 children with acute LRTI (aged 1 month to 10 years, median age 6 months) within 24 hrs after admission for bacterial culture. Meanwhile respiratory viruses were detected by the Direct immunofluorescence (DIF) assay. The K-B method was applied for the drug susceptibility test. RESULTS: Etiological agents were identified in 297 cases out of 454 patients (65.4%. Viral pathogens were identified in 229 cases (50.4%), bacteria in 135 cases (29.7%) and mixed viral-bacterial infections in 67 cases (14.8%). The isolating rate of Respiratory syncytial virus (RSV) was the highest (180 cases, 39.6%) in all of the samples. The isolating rates of other viral pathogens were as follows: Parainfluenza virus 3 type (PIV3) (6.6%), Adenovirus (2.2%), Influenza A (0.9%) and Influenza B (0.7%). Of the 135 strains of bacterial pathogens, 19 kinds of bacterial pathogens were isolated. The predominant isolate was Klebsiella pneumoniae (K. pneumoniae) (9.9%), followed by Escherichia coli (E.coli) (4.4%), Streptococcus pneumoniae (S. pneumoniae) (4.2%) and Staphylococcus aureus (S. aureus) (4.2%). The isolating rates of K. pneumoniae and E.coli with extended-spectrum beta-lactamases strains (ESBLs) positive were 42.2% and 65.0%, respectively. The pathogens isolated of the first 5 places in children with acute LRTI under six months were RSV, K. pneumoniae, PIV3, E.coli and S. aureus in turn. RSV, PIV3, S. pneumoniae, K. pneumoniae and E.coli were found to be the pathogens of the first 5 places in children with acute LRTI between six months and three years. The resistant rates of K. pneumoniae and E.coli to ampicillin were 97.8% and 75.0%, respectively. K. pneumoniae and E.coli with positive ESBLs were resistant to cephalosporin. The resistant rates of S. pneumoniae to erythromycin and penicilin were 100% and 68.4%, respectively. The resistant rates of S. aureus to erythromycin and penicillin were 94.7% and 89.5%, respectively. CONCLUSIONS: RSV is the most common pathogen responsible for acute LRTI in children in Wenzhou City, followed by K. pneumoniae and PIV3. The rate of antibiotic resistance of common bacteria and the isolating rate of Gram-negative bacillus with ESBLs positive are high.

Acute Disease↗

PubMed1996

Community-based respiratory viral infections in HIV positive patients with lower respiratory tract disease: a prospective bronchoscopic study.

OBJECTIVES: To evaluate the contribution of community-based respiratory virus infections to lower respiratory tract disease in HIV-1 infected individuals. DESIGN: Prospective clinical cohort study. SETTING: Specialist in-patient unit for HIV and AIDS, University College London Hospitals, London. SUBJECTS: 44 consecutive HIV-1 antibody positive patients who underwent 47 diagnostic bronchoscopies for evaluation of the symptoms and signs of lower respiratory tract disease. TIME: Winter months of 1994/95. MAIN OUTCOME MEASURES: Detection, in bronchoscopic alveolar lavage fluid, of infection with influenza A and B, respiratory syncytial virus (RSV), parainfluenza 1, 2 and 3 (by immunofluorescence and cell culture) and adenovirus and enteroviruses (by cell culture). RESULTS: No evidence of influenza, RSV, parainfluenza, adenovirus, or enterovirus infection was detected. CONCLUSIONS: Despite a marked increase in RSV and influenza B infection in the general population over the winter of 1994-95, respiratory virus infections were not detected in this cohort of HIV infected patients. As the organisms causing lower respiratory tract disease were related to immunosuppression, this study questions the value of routine identification of community-based respiratory viruses in this patient group.

AIDS-Related Opportunistic Infections↗

PubMed1997

The kinetics of grain dust-induced inflammation of the lower respiratory tract.

To characterize the kinetics of grain dust-induced airflow obstruction and inflammation in the lower respiratory tract, we performed serial spirometry and bronchoalveolar lavage (BAL) in human subjects and whole-lung lavage in mice following a single inhalation exposure to comparable dosages of corn dust extract (CDE). Following inhalation of CDE, our human study subjects developed significant airflow obstruction 10 min postexposure which persisted for 48 h. Human subjects and mice had similar acute and persistent changes in lavage cellularity after exposure to CDE. A profound increase in the concentration of lavage neutrophils was present in the initial postexposure lavage in both human subjects and mice. This increase persisted for 96 h in human subjects and 48 h in mice. Small but significant increases in lavage macrophage concentration were present 48 h postexposure in human subjects and at 96 h postexposure in mice. Inhalation of CDE resulted in a significant increase in the concentration of proinflammatory cytokines tumor necrosis factor-alpha (TNF-alpha) and interleukin-6 (IL-6) in the lavage fluid of both human subjects and mice. Similarly, significant increases in lavage concentrations of IL-8 in humans and macrophage inflammatory protein-2 (MIP-2) in mice occurred after inhalation of CDE. The lavage concentration of all measured proinflammatory cytokines returned to baseline levels by 168 h in humans and 96 h in mice. These findings suggest that a single inhalation challenge of CDE results in airflow obstruction and lower respiratory tract inflammation that may last for several days. These physiologic and inflammatory responses appear to be self-limited with no evidence of persistent injury 1 wk after the inhalation challenge. Moreover, the inflammatory response in the lower respiratory tract after inhalation of grain dust is similar in human subjects and mice, suggesting that the mouse may be an appropriate model for further investigation of grain dust-induced inflammation.

Adult↗

PubMed2002

[A three-year review of acute respiratory tract infections caused by Streptococcus milleri group].

The objective of our study is to understand the clinical features of patients with acute respiratory tract infection associated with Streptococcus milleri group (SMG). Fifteen patients with SMG respiratory tract infection visited our hospital from July, 1997 through May, 2000. There were seven cases of pneumonia, two pulmonary abscess, three thoracic empyema and three acute bronchitis. The mean age of the patients was 57.8 years (range 16-87), twelve were males, and seven were smokers. The moderately to severe underlying diseases existed in thirteen patients (86.7%) and included the following: respiratory diseases (20.0%), history of the esophageal or gastric surgery (26.7%), central nerve system diseases (13.3%), alcohol intake (60.0%), hepatitis and pancreatitis (33.3%), diabetes mellitus (13.3%) and malignancy (6.7%). The species of SMG detected were as follows: S. constellatus, 8, S. anginosus, 6 and S. intermedius, 1. Anaerobic organism and other microorganisms were detected in five patients. A patient with SMG nosocominal pneumonia who previously had thoracic surgery for esophageal cancer died. Antibiotics therapy with carbapenem or combination therapy, drainage and no surgery, were successful in 14 of the 15 cases (93.3%). The number of intermediately or complete resistant strains against penicillin G, ampicillin and cefmetazole were 5 (33.3%), 8 (53.3%) and 12 (80.0%), respectively in this series. Recently, it is seemed that acute respiratory tract infections caused by SMG are increasing in the patients with moderately to severe underlying diseases, and several clinical strains of SMG are acquiring a tolerance to antibiotics.

Acute Disease↗

PubMed1998

Monitoring and detection of acute viral respiratory tract disease in horses.

OBJECTIVE: To develop a system to monitor and detect acute infections of the upper respiratory tract (i.e., nares, nasopharynx, and pharynx) in horses and to assess the association among specific viral infections, risk factors, and clinical signs of disease. DESIGN: Prospective study. ANIMALS: 151 horses with clinical signs of acute infectious upper respiratory tract disease (IURD) from 56 premises in Colorado. PROCEDURE: Health management data, blood samples, and nasal or nasopharyngeal swab samples were obtained for 151 horses with clinical signs of acute IURD. Of these horses, 112 had an additional blood sample obtained during convalescence and were considered to have complete sample sets. Samples were tested for evidence of respiratory tract infection by use of ELISA, virus isolation, and serologic testing of paired serum samples. RESULTS: Viral infections were identified in 65 horses with complete sample sets; influenza virus infection was identified in 43 horses, equine herpesvirus (EHV) infection in 18, and mixed influenza virus and EHV infections in 4. On 14 premises, samples were obtained from more than 1 affected horse. Viral infections were identified in horses on 11 of 14 premises. Equine herpesviruses were isolated from 10 horses. A relationship was not found between vaccination history and identification of EHV or influenza virus infections. An infection with EHV was less likely to be identified in horses with initial (acute) antibody titers > 1:16 to EHV. CLINICAL IMPLICATIONS: Influenza virus (specifically, A/equine/2) was the most common virus associated with acute IURD. Use of multiple diagnostic tests and obtaining samples from more than 1 horse in an outbreak may improve detection of viral infections.

Acute Disease↗

PubMed2003

Diagnosis of upper respiratory tract diseases in the performance horse.

Wastage of performance horses because of respiratory dysfunction is common. Appropriate identification of the disease is paramount for treatment recommendations. Diagnostic modalities for upper respiratory tract dysfunction include a thorough physical examination, radiographic evaluation when appropriate, and upper respiratory tract endoscopy. Anatomical deviations or structural are easily identified during resting evaluation, while exercise testing is often necessary to assess thedynamic properties of the upper airway. Utilizing the many diagnostic tools available allows the clinician to make an accurate diagnosis and recommend appropriate treatment.

Animals↗

PubMed1986

Origin of immunoglobulins in respiratory tract secretion and saliva of sheep.

The origin of the immunoglobulins in the upper respiratory tract secretion of sheep was determined by measuring the distribution between plasma and secretion of radiolabelled purified immunoglobulins and albumin. By calculation of the ratio of specific activity for each immunoglobulin between plasma and secretion, it was estimated that about 81% of IgA in secretion was of local origin, whereas IgM, IgG1, IgG2 and albumin were wholly derived from plasma. Estimates of the selectivity of transport of IgA and IgM into both respiratory tract secretion and saliva were obtained by calculation of a selective index relative to IgG1 or IgG2, which do not bind secretory component (SC). This was based on radioactivity ratios after the simultaneous injection of immunoglobulin labelled with different isotopes (IgA or IgM injected with either IgG1 or IgG2). These calculations revealed that both IgA and IgM were selectively transported into respiratory tract secretion and saliva. This provides further support for the proposition that SC-binding immunoglobulins may be transported from serum into secretions at a variety of mucosal sites dependent on SC availability. Since the IgA in serum of sheep is predominantly of gut origin, this provides an opportunity, in addition to relocation of gut-derived plasma cell precursors, by which the gut may contribute to extraintestinal mucosal responses.

Albumins↗

PubMed2004

[Bronchoscopic specimen collection, role of the protected specimen brush in lower respiratory tract infections].

INTRODUCTION: The ineffectiveness of microbiological methods in the lower respiratory tract infections are caused by anachronistic sampling methods. Authors checked the protected specimen brush effectiveness and those of the influencing factors. MATERIALS AND METHODS: 103 patients were involved in the study. The causative agents were identified in 44 cases. These results were compared to last year's classic sampling techniques and they experienced 20.4% improvement of the sensitivity. Further increasing in effectiveness can be reached if we perform bacteriological sampling after the first unsuccessful antibiotic treatment was performed. Out of 103 examined patients only 69 underwent antibiotic treatment. In the case of 13 patients after the course of one type antibiotic treatment 10 positive bacteriological cultures were positive. In the case of 31 patients 2 types of antibiotics were administered sequentially and examined afterwards and the authors found 15 positive bacteriological cultures. In the case of 25 patients the administered sequentially 3 times of antibiotics and examined afterwards, 6 cultures were positive. CONCLUSION: The examinations prove that the protected specimen brush, used in time, raises the sensitivity of microbiological processes.

Adult↗

PubMed1975

Problems and progress towards vaccination against bacterial infections of the respiratory tract.

A large number of bacterial species are causative agents of respiratory tract disease. The discussion will center on three infections selected because they represent different problems in control on the basis of epidemiologic and immunochemical factors. Group A hemolytic streptococci are common upper respiratory tract pathogens which may initiate severe non-suppurative sequelae such as rheumatic fever and glomerulonephritis. Recent progress concerning M protein vaccines will be reviewed. Pneumococci are still the most frequent cause of pneumonia at all ages. Pneumococcal vaccines are the prototype for purified polysaccharide vaccines since their effectiveness was demonstrated 30 years ago. The major problem in vaccination is the very large number of capsular serotypes. Pseudomonas aeruginosa represents the relatively new problem of gram-negative bacterial infections in the immunodepressed host. Demonstration of seven immunotypes as the cause of 90% of human infections has led to preparation of a multivalent vaccine composed of lipopolysaccharide antigens. Current knowledge of this vaccine will be discussed.

Antigens, Bacterial↗

PubMedDate not supplied

Acute respiratory tract infections among a birth cohort of children from Cali, Colombia, who were studied through 17 months of age.

For this study, 340 children less than 18 months old from a low-income, urban neighborhood in Cali, Colombia, were observed from birth by means of weekly home visits to detect cases of acute respiratory tract infection. All suspected cases were confirmed by trained doctors in a special clinic. Information on symptoms, signs, and potential risk factors was documented prospectively. Etiologic agents were identified in cases of lower respiratory tract infection (LRI). The overall incidence of acute respiratory tract infection was 6.6 cases per child-year at risk. The incidence of upper respiratory tract infection was 4.9 cases per child-year at risk and that of LRI was 1.7 cases per child-year at risk. Crowding in the home was found to be significantly associated with an increased incidence of LRI. Respiratory syncytial virus was the viral agent most frequently isolated from cultures of nasopharyngeal aspirates of children with LRI. Staphylococcus aureus was the bacterial agent most frequently isolated from the blood of patients with LRI.

Acute Disease↗

PubMed1987

[Suitability of fiberscopy of the upper respiratory tracts during esophagogastroduodenoscopy and bronchoscopy].

Prophylactic fibroscopic examination of the upper respiratory tract was carried out in 1,201 patients, 1,038 of them being simultaneously subjected to fiber esophagogastroduodenoscopy and 163--to fiber bronchoscopy. Specimens for cytomorphologic examination were taken from 393 cases. In 18.2%, various pathology of the upper respiratory tract was found, including inflammation in 9.7%. The group at high risk for cancer included 2.9% of examinees. Malignancies were detected in 0.08%.

Adolescent↗

PubMed2007

High prevalence of human bocavirus detected in young children with severe acute lower respiratory tract disease by use of a standard PCR protocol and a novel real-time PCR protocol.

The human bocavirus (HBoV) was recently isolated from respiratory tract samples. Within a study collective of children with severe lower respiratory tract disease, the patients testing positive for HBoV (12.8%) had a higher rate of underlying cardiopulmonary disease. Viral loads in respiratory tract specimens varied from 10(2) to 10(10) genome equivalents/ml.

Acute Disease↗

PubMed1982

The role of BK virus in acute respiratory tract disease and the presence of BKV DNA in tonsils.

The significance of BKV infections relative to infections by generally tested respiratory agents was investigated in children with acute respiratory disease. Paired sera from 177 children admitted to a hospital for acute respiratory disease were tested for significant rises in antibodies. Sera from seven patients showed a seroconversion to BKV and clinical signs of acute upper respiratory tract infection were exhibited by each of these patients. BKV infections were present in 8% of the patients with upper respiratory tract disease while seroconversions to adenovirus (2%), influenza A virus (1%), parainfluenza virus (5%), RS virus (6%) and mycoplasma pneumoniae (1%) were observed in 15% of the patients with upper respiratory tract disease. BKV was isolated from the urine of one child with tonsillitis with a concomitant seroconversion to BKV. Tonsils from children with recurrent attacks of acute respiratory disease were tested for the presence of BKV DNA by hybridization with a cloned genomic 32P-labeled DNA of prototype BKV. Five of twelve tonsil DNAs showed hybridization with BKV DNA. Each tonsil showing hybridization with BKV DNA contained multiple nonintegrated copies of the BKV genome per diploid amount of host cell DNA. Attempts to recover infective BKV by transfection of primary human embryonic cells with tonsil DNAs or by co-cultivation of tonsillar cells with primary human embryonic cells were unsuccessful.

Acute Disease↗

PubMed2002

Assessment of polymerase chain reaction and serology for detection of chlamydia pneumoniae in patients with acute respiratory tract infection.

OBJECTIVE: To study Chlamydia pneumoniae (C. pneumoniae) infection in 110 patients with respiratory tract infection admitted to our hospital from January to December 1995 in Nanjing. METHODS: Sputum and throat swab specimens were taken and C. pneumoniae DNA was detected by using polymerase chain reaction (PCR) with the HM-1-HR-1 primer pair. At the same time, serum samples were taken and immunoglobulin G and M (IgG and IgM) fractions of antibodies to C. pneumoniae were studied by microimmunofluorescence test. RESULTS: Prevalence of specific IgG was 70% in patients with respiratory tract infection. Seventeen patients (15.5%) were serologically diagnosed as having recent C. pneumoniae infections and 12 patients (10.9%) had positive PCR in sputum and/or swab specimens. The total positive rate was 22.7% (25/110) detected by PCR combined with serological tests. Acute infection of C. pneumoniae was common in patients with asthma (57.1%), pneumonia (35.0%), COPD (25.9%) and bronchitis (25.0%). Clinical features between C. pneumoniae infection and non-C. pneumonia infection showed no significant differences. CONCLUSIONS: Chlamydia pneumoniae is an important pathogen that causes infection of the human respiratory tract and attention should be drawn to this special illness.

Acute Disease↗

PubMed2001

Prothrombotic changes in hemostatic parameters and C-reactive protein in the elderly with winter acute respiratory tract infections.

Mortality rates attributable to cerebrovascular and ischemic heart disease increase among older adults during the winter. Prothrombotic changes in the hemostatic system related to seasonal factors, such as ambient temperature changes, and winter acute respiratory tract infections, may contribute to this excess seasonal mortality. A prospective nested case-control study was conducted to assess the impact of winter acute respiratory tract infections on fibrinogen, factor VII, factor VIIa, D-dimer, prothrombin fragment 1.2, PAI-1, soluble P-selectin and C-reactive protein (CRP) in older adults. The change in laboratory parameters from baseline (fall) to the time of infection in both middle-aged and elderly individuals was compared with matched non-infected controls. In older adult participants with winter acute respiratory tract infections, significant increases occurred in fibrinogen and C-reactive protein, but not in any other markers. The mean fibrinogen increased 1.52 g/L (38%) and the mean CRP increased 37 mg/L (370%) over baseline (both p <0.001). In a multivariate analysis, both infection and season were associated with the increase in fibrinogen, but only infection was associated with the CRP increase. Old age magnified the increase in CRP but not in fibrinogen. Winter acute respiratory tract infections induce an exaggerated inflammatory response in older adults. The associated increase in fibrinogen, an independent risk factor for ischemic heart disease, may be partly responsible for the excess winter vascular mortality.

Acute Disease↗