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PubMed1999

Antibody responses after Sendai virus infection and their role in upper and lower respiratory tract disease in rats.

BACKGROUND AND PURPOSE: Sendai virus infection in rats is an excellent model for studying development and role of host defenses throughout the respiratory tract after this infection. Therefore, development of serum antibody responses and disease were studied. METHODS: Forty-two anesthetized pathogen-free 3- to 4- week-old LEW/NCr rats were inoculated intranasally with Sendai virus. At postinoculation days 0, 2, 3, 5, 8, 10, and 14, rats were euthanized by administration of a pentobarbital sodium overdose followed by exsanguination. Serum was obtained from all animals, and nasal wash and bronchoalveolar lavage specimens were collected during selected experiments. An ELISPOT assay was used to measure numbers of Sendai virus-specific antibody-forming cells in respiratory tract lymphoid tissue. RESULTS: Recovery from disease and clearance of virus from respiratory tract tissues coincided with development of serum antibody responses. Upper respiratory tract lymph nodes were the initial and major sites of appearance of antibody-forming cells. Immunoglobulin G was the predominant subtype of these cells during recovery from the infection and in rats resistant to infection. Passive transfer of antisera or specific IgG protected the lower but not the upper respiratory tract. CONCLUSIONS: Circulating components of immunity have a major role in resistance and recovery from disease in the lower respiratory tract, whereas local responses are likely involved in protection of the upper respiratory tract. Local lymphoid tissues are the major production sites of IgG, which contributes to resistance to and recovery from respiratory tract diseases.

Animals↗

PubMed2005

Recovery of bacteria from broiler carcass respiratory tracts before and after immersion scalding.

Occlusion of the trachea and decapitation were compared with a conventional unilateral neck cut for effects on bacteria entering into the respiratory tract of broiler carcasses during scalding. In experiment 1, the trachea was occluded prior to the carcass entering the scalder to determine if bacterial recovery from the respiratory tract could be diminished. The first carcass was removed at the end of bleeding, and a plastic cable tie was placed around the neck of a second carcass and tightened to occlude the trachea. After proceeding through the triple-tank immersion scalder, the second carcass (trachea occluded) was removed, and a third carcass (without the trachea occluded during scalding) was removed. In experiment 2, after being stunned, carcasses were unilaterally bled or decapitated. Unilaterally bled and decapitated carcasses were removed at the end of bleeding and after scalding. In both experiments, trachea were cannulated, and respiratory tract rinses were collected. For experiment 1, the numbers of bacteria recovered (log10 cfu/mL of rinse) from prescald nonoccluded carcass respiratory tract rinses were 2.5 Escherichia coli, 2.6 coliforms, and 3.2 total aerobes. Respiratory tract rinses from carcasses sampled postscald (without occluding the trachea) had higher bacteria numbers at 4.6 E. coli, 5.0 coliforms, and 5.4 total aerobes. Respiratory tract rinses from carcasses with the trachea occluded prior to scalding had the lowest number of bacteria at 1.9 E. coli, 2.3 coliforms, and 2.7 total aerobes. In experiment 2, the numbers of bacteria recovered from respiratory tract rinses of unilaterally bled or decapitated carcasses did not differ prescald or postscald, although all postscald values were higher (P < 0.05). Results confirmed that bacteria numbers increased within the respiratory tract during immersion scalding, the increase could have been prevented by occluding the trachea prior to scalding, and decapitation did not alter the number of bacteria recovered from respiratory tract rinses prior to or following immersion scalding.

Animals↗

PubMed1991

Specific and nonspecific antibody responses in different segments of the respiratory tract in rats infected with Mycoplasma pulmonis.

Murine respiratory mycoplasmosis resulting from Mycoplasma pulmonis infection in rats provides a useful model for the study of immunological and inflammatory mechanisms operative in the respiratory tract. We have previously shown that LEW rats develop more severe disease than do F344 rats. To further study the production of antibody responses in chronic respiratory disease due to M. pulmonis infection, we examined the distribution and development of M. pulmonis-specific antibody-forming cells (AFC) in different segments of the respiratory tracts of infected LEW and F344 rats. In these studies, the upper respiratory nodes were the initial site of antibody production after infection and remained the major site for recovery of AFC. Since infected LEW rats had equal or higher numbers of AFC than did infected F344 rats, these results suggest that the level of local antibody production alone is not responsible for the decreased susceptibility of F344 rats to murine respiratory mycoplasmosis. The differences in total antibody responses appear to be due to the greater numbers of cells recovered from the tissues of infected LEW rats compared with those recovered from F344 rats, suggesting that LEW rats may have greater production of chemotactic factors. Also, we demonstrate that nonspecific activation and/or recruitment of B cells occurs in the respiratory tracts of both LEW and F344 rats after infection with M. pulmonis.

Animals↗

PubMed1994

Effects of air pollution on the upper respiratory tract of children.

The impact of the environment on the upper respiratory tract of children has become an issue of recent interest. Sulfur dioxide causes nasal congestion in children as well as an increase in both mast cells and lymphocytes in nasal lavage fluids. Chlorpheniramine blocks the effect of sulfur dioxide on the nasal mucosa. Ozone exposure results in nasal congestion, increased levels of histamine, neutrophils, eosinophils, and mononuclear cells in nasal lavage fluid. No data are available on the effects of nitrogen dioxide or wood-burning stoves on the upper respiratory tracts of children. Formaldehyde in sufficient concentrations causes upper airway irritation; however, no data are available on its long-term effects. Detriments in air quality cause adverse changes in the lower respiratory tracts of susceptible individuals. The effects on the upper respiratory tract are more difficult to document. There may be a causal relationship, but definitive proof of whether air pollution results in significant increases in pediatric otitis media, sinusitis, rhinitis, and pharyngitis has yet to be demonstrated.

Air Pollutants↗

PubMed2005

[Q fever in acute exacerbation of chronic lower respiratory tract infection].

We studied the effect of Q fever in acute exacerbation of chronic lower respiratory tract infection. The subjects consisted of 80 cases with acute exacerbation of chronic lower respiratory tract infection treated during the period from March 2002 till October 2004. Q fever was diagnosed using a PanBio Coxiella burnetii ELISA test kit. Two cases (2.5%) were positive for IgM in the acute stage, and were diagnosed as having acute infection by C. burnetii. They were elderly women with bronchiectasis, aged 76 and 82. They had no history of keeping cats or dogs, but the onset of acute exacerbation of chronic lower respiratory tract infection was June and March which is the breeding seasons for cats and dogs. Acute exacerbation of chronic lower respiratory tract infection were considerd to be a mixed infection with Pseudomonas aeruginosa (the 76-year-case) and Haemophilus influenzae (the 82-year-case). It is concluded that C. burnetii can induce exacerbation of chronic lower respiratory tract infection, their cases were considerd to be mixed infection with C. burnetii and other bacteria.

Acute Disease↗

PubMed1997

[Detection of methicillin-resistant Staphylococcus aureus (MRSA)--relation between respiratory tract and gastro-intestinal tract].

The study was conducted to elucidate the possibility of hospital infection of methicillin-resistant Staphylococcus aureaus (MRSA) through feces. Fecal cultures of 12 inpatients positive for MRSA in the respiratory tract and 11 inpatients negative for MRSA in the respiratory tract were performed from April to October in 1993. Fecal cultures of inpatients positive for MRSA in the respiratory tract were continued until September in 1996, finally a total of 50 cases were enrolled. MRSA was isolated from feces of 7 patients (58.3%) of the 12 patients positive for MRSA in the respiratory tract, while no MRSA was isolated from feces of 11 patients negative for MRSA in the respiratory tract. Twenty-seven patients (54.0%) of 50 patients positive for MRSA in the respiratory tract yielded MRSA in the feces. Twenty-three patients (85.2%) of the 27 patients positive for MRSA in the fecal flora had received H2-blocker, while 11 patients (47.8%) of the 23 patients negative for MRSA in the fecal flora received H2-blocker; these differences were statistically significantly (p < 0.01). These findings suggest the possible role of feces in hospital infection with MRSA and the necessity for careful administration of H2-blocker to patients positive for MRSA in the respiratory tract.

Aged↗

PubMed1993

Clinical and endoscopic study to estimate the incidence of distal respiratory tract infection in thoroughbred foals on Ontario breeding farms.

Respiratory tract infections are prevalent in foals, yet the frequency with which the distal airways are affected in clinical episodes of respiratory tract disease has not been evaluated to our knowledge. The objective of the study was to determine the incidence of distal respiratory tract infection (DRTI) in foals on a sample of Thoroughbred breeding farms (n = 10) in Ontario. In a pilot study, clinical criteria commonly used to select foals for antimicrobial treatment (detection of abnormal lung sounds, plus nasal discharge, cough, fever, tachypnea, and/or lethargy) were found to segregate foals with and without endoscopically confirmed DRTI. Mucopurulent exudate and bronchial erythema were observed more frequently (P < 0.005), bronchial lavage total cell count and neutrophil concentration were significantly (P < 0.005) higher, and intracellular cocci were recovered significantly (P < 0.01) more often from bronchial lavage samples of affected foals (n = 8) than of controls (n = 8). These clinical criteria were used to identify cases in a cohort of Thoroughbred foals (n = 219) from May 1 to October 30, 1991. Case morbidity adjusted for clustering was 82 +/- 5% (95% confidence limits, 72 to 92%). Most (74%) episodes of clinical DRTI were detected in July and August, and equal numbers were detected before (53%) and after (47%) weaning of foals. Of 178 cases, 66 (48%) were selected at random for endoscopy and bronchial lavage. Grade-II pharyngeal lymphoid hyperplasia was observed commonly (60% of foals); auditory tube diverticulum (guttural pouch) discharge was observed in 18 of 86 (21%) foals, and guttural pouch infection was confirmed in 6 of 7 foals examined endoscopically.(ABSTRACT TRUNCATED AT 250 WORDS)

Animals↗

PubMed1981

Second primary respiratory tract malignant neoplasms in supraglottic carcinoma.

In this study, a second respiratory tract malignant neoplasm developed in 20 of 163 cases of supraglottic carcinoma either at the time of diagnosis or after diagnosis. Using an actuarial method of calculation, 19% of the survivors will experience a second respiratory tract malignant neoplasm within five years after the diagnosis of supraglottic carcinoma. This is three times the incidence in patients who survive glottic carcinoma and 14 times the incidence in the normal population. A third of this group of patients with supraglottic carcinoma are alive and well at five years, a third died of supraglottic cancer, and a third died of intercurrent disease. The death rate from intercurrent disease is twice that seen in the general population, and this difference is due almost entirely to second respiratory tract tumors. Even if the cure rate of patients with primary supraglottic carcinoma was 100%, only half of these patients would actually be alive at five years, owing to deaths from intercurrent disease. More emphasis needs to be placed on the reduction of the mortality from second respiratory tract tumors with the use of screening or preventive methods.

Glottis↗

PubMed2001

Worldwide guidelines for respiratory tract infections: community-acquired pneumonia.

The management of respiratory tract infections is a complex process. Concern over increasing levels of bacterial resistance and the inappropriate use of antibiotics has led to the development of clinical guidelines for the treatment of respiratory tract infections. Despite the development of these guidelines, a consensus on the optimal care for lower respiratory tract infections has not been attained. Guidelines for the management of community-acquired pneumonia (CAP) have been developed since the 1990s in the USA, Canada, and a number of European countries. Constant re-evaluation of guidelines for CAP is necessary to ensure that the recommendations that were made in the early 1990s still hold true in the new millennium.

Anti-Bacterial Agents↗

PubMed1990

Functional role of respiratory tract haemagglutinin-specific IgA antibodies in protection against influenza.

Intranasal inoculation of haemagglutinin (HA) purified from influenza virus A/PR/8/34 (PR8, H1N1) together with cholera toxin B subunit, into Balb/c mice resulted in complete protection against PR8 infection in parallel with the induction of high levels of HA-specific IgA and IgG antibodies on the respiratory tract. The respiratory tract IgA and IgG were purified from nasal and lung washings of the immunized mice using affinity columns, and their HA-specific activities were measured by enzyme-linked immunosolvent, plaque neutralization and haemagglutination inhibition assays. The purified IgA and IgG had the following properties: (1) They were able to neutralize virus in vitro. (2) The purified IgA included major antibodies directed against PR8 virus and minor antibodies cross-reactive with A/Yamagata/120/86 (H1N1) or A/Fukuoka/C29/85 (H3N2) virus, while the purified IgG included major antibodies to the homotypic virus, minor antibodies to the H1N1 virus and only a trace amount of antibodies to the H3N2 virus. (3) When separated on a Sephacryl column, most of the IgA anti-HA activities occurred in the polymeric fractions of purified IgA, whereas the IgG anti-HA activities occurred in the monomeric fractions. (4) When passively administered to normal mouse respiratory tract before infection, the purified IgA protected against PR8 infection. These results suggest that HA-specific, polymeric IgA antibodies on the respiratory tract by themselves provide not only protection against the homotypic virus but also higher levels of heterotypic immunity than IgG.

Animals↗

PubMed1999

Cotinine in meconium indicates risk for early respiratory tract infections.

1. In order to identify potential risks for lower respiratory tract symptoms during early infancy, the concentration of cotinine was measured in meconium of 91 newborns as a parameter of prenatal exposure to tobacco, and a questionnaire was performed with parents at birth. Infants were followed up for the first year of life by monthly telephone interviews. 2. Lower respiratory tract infections during the first 6 months of life were associated with a high concentration of cotinine in meconium (cotinine higher than median vs lower than median; odds ratio 4.9, 95% confidence interval 1.2 to 20.3), while none of the other variables tested including selfreport of parental, prenatal or postnatal tobacco consumption, parents history of atopy, maternal age, presence of siblings, socio-economic status, duration of gestation, birth weight, gender, and duration of breast feeding were identified as independent risks. The occurrence of a lower respiratory tract infection during the first 6 months of life was predicted correctly in 77% of the infants by a cotinine excretion in meconium exceeding the group median. 3. In conclusion, quantification of cotinine in meconium is preferred to historical parameters as an estimate of the risk for early respiratory tract infections.

Adult↗

PubMed1986

Clinical evaluation of ofloxacin in lower respiratory tract infections.

The clinical efficacy and the safety of ofloxacin in lower respiratory tract infections were evaluated by 42 research groups in Japan. 127 patients with bacterial pneumonia and 399 patients with chronic lower respiratory tract infection were analyzed for clinical efficacy. The drug was orally administered, mostly in daily doses of 300 mg to 600 mg for an average of 15 days. The therapeutic success rate was 80% in bacterial pneumonias and 78% in chronic lower respiratory tract infections. As for bacteriological response, eradication rates of 93% and 72%, respectively, were observed against isolates from bacterial pneumonias and chronic lower respiratory tract infections. Side effects mainly in the gastrointestinal tract and central nervous system were noted in 7.6% of 540 patients, but none of them was severe.

Adolescent↗

PubMed1990

[Analysis of immunoglobulin G subclasses in chronic respiratory tract infections].

To analyze the immunological aspects of chronic respiratory tract infections, immunoglobulin G (IgG) subclass patterns were investigated in 20 patients with diffuse panbronchiolitis (DPB) and 20 patients with cystic bronchiectasis (CBE). All IgG subclasses were increased in both diseases in comparison to the normal group. Increased levels of IgG1 and IgG2 were recognized more dominantly in DPB, whereas IgG4 level was elevated in CBE. Furthermore, analysis of the ratio of IgG subclass to total IgG showed increase of IgG1 and decrease of IgG2 in both diseases, and increase of IgG4 only in CBE. On the other hand, the increase of IgG1 correlated with infection by P. aeruginosa while increase of IgG4 was recognized in the group of non-P. aeruginosa infections. These results indicate that increased IgG1 and IgG2 levels are common characteristic phenomena in chronic respiratory tract infections such as DPB and CBE, reflecting the pathophysiological aspects based on respiratory tract defense mechanisms against microorganisms, and demonstrated that differences of IgG subclass patterns are observed among DPB and CBE, and also according to causative agents.

Adult↗

PubMed1992

Changes in the spectrum of organisms causing respiratory tract infections: a review.

Over the last decade, the spectrum of organisms causing community-acquired acute lower respiratory tract infections has changed. Streptococcus pneumoniae now causes approximately 30% of outpatient acute pneumonia-less than in former decades-whereas Mycoplasma pneumoniae is found in both young and elderly patients. The Enterobacteriaceae and Staphylococcus aureus are now seen more frequently as respiratory tract pathogens in community-acquired pneumonia patients, and they are the major organisms causing pneumonia in residents of homes for the elderly or nursing homes, and in immuno-compromised patients. Agents that were previously considered non-pathogenic for the respiratory tract include serotypes of Haemophilus influenzae other than type b, H. parainfluenzae and Moraxella (Branhamella) catarrhalis; these organisms affect mainly patients with underlying cardiopulmonary disease. Legionella species can cause sporadic as well as epidemic disease of the lower respiratory tract. Chlamydia pneumoniae is a newly recognized pathogen responsible for mild to severe upper and lower respiratory tract infections. In 60-80% of cases, hospital-acquired pneumonias are caused by Gram-negative bacilli and S. aureus. These organisms colonize the mucosal membranes of the upper respiratory tract and penetrate into the lower tract by aspiration or intubation.

Bronchitis↗

PubMed1999

[Study on combined detection of M. genitalium, M. pneumoniae and C. pneumonia by nested polymerase chain reaction in respiratory tract infections in pediatric patients].

OBJECTIVE: To study the respiratory tract infections by Mg, M. genitalium (Mpn), Cpn, and co-infections by these agents in pediatric patients. METHODS: Mg DNA, Mpn DNA and Cpn DNA were detected in respiratory tract specimens obtained by throat swab from 231 children by the nested polymerase chain reaction (PCR) technique. DNA sequencings were detected and analysed between every two positive specimens of Mg and Cpn and typical strains. RESULTS: Positive rates of Mg DNA, Mpn DNA and Cpn DNA by nested PCR in 231 children were 22.5%, 30.7% and 32.9%. The Positive rates of co-infection were 5.2% (Mg and Mpn), 2.6% (Mg and Cpn), 10.8% (Mpn and Cpn) and 8.7% (Mg and Mpn and Cpn). There was only one base mutation in 1 Mg DNA. Other DNA sequencings were same as those from model strains. The homogeneity was 99.8%. CONCLUSIONS: Mg could be one of the pathogens in respiratory tract infections in pediatric patients. There exists co-infection by Mg, Mpn and Cpn.

Child↗

PubMed1970

Etiologic diagnosis of lower respiratory tract infections.

Decision as to the role of infection in lower respiratory tract disease requires examination by culture of specimens known to be derived from the infra-laryngeal respiratory tract. Methods that involve the upper respiratory tract in collection of specimens entail the hazard of contamination by microbiota resident in the upper respiratory tract.The extrapulmonary approaches of cutting-needle biopsy and needle aspiration of intrathoracic disease have not been impressively productive of etiologic diagnosis of infections. While open-chest surgical biopsy has been a highly effective means to diagnosis, this approach does have special requirements in facilities and technical skills.Percutaneous transtracheal aspiration of tracheo-broncho-pulmonary secretions-exudates has been productive of useful information. Because of inherent simplicity and safety, transtracheal aspiration should precede resort to more demanding, difficult, dangerous procedures.

Humans↗

PubMed1995

Occurrence of respiratory syncytial virus subtypes in Mexican infants with acute lower respiratory tract disease.

The occurrence of respiratory syncytial virus (RSV) subtypes in Mexico City was studied by searching for the virus in nasopharyngeal aspirates of 82 infants, less than 12 months of age, hospitalized for acute lower respiratory tract disease with diagnosis of bronchitis, bronchiolitis, pneumonia and laryngotracheobronchitis. The presence of respiratory virus was determined by observation of cytopathic effect in cell monolayers; samples which produced a clear syncytia were considered positive and were treated with anti-respiratory syncytial virus serum. Viral infectivity was neutralized in 21 samples which were regarded as having RSV. These specimens were characterized into subtypes A and B with specific monoclonals by indirect immunofluorescence. Subtype A predominated over subtype B, 19 vs. 2. Patients with pneumonia and laryngotracheobronchitis had subtype A and both subtypes were found in infants with bronchitis and bronchiolitis.

Acute Disease↗

PubMed1994

[Epidemiological study on respiratory syncytial virus lower respiratory tract infections in northern Hokkaido, Japan].

We carried out an epidemiological study on lower respiratory tract infections, concerning the respiratory syncytial virus (RSV) infection, in northern Hokkaido, Japan, during the 2-year-study period from April 1991 to March 1993. There were 467 hospitalized patients with lower respiratory tract infections. We examined the presence of RSV antigen in their nasopharyngeal specimens of 456 out of 467 patients (97.6%) by enzyme immunoassay. The diagnosis of Mycoplasma pneumoniae infection was done by the rise of antibody titer, performed with complement fixation method, in the sera of the acute and convalescent phases. There were 133 patients with RSV infection (28.9%), 45 patients with Mycoplasma pneumoniae infection (9.8%) and 7 patients with measles virus infection (1.5%). RSV played an important role in the lower respiratory tract infections in northern Hokkaido, Japan. The epidemic of RSV infection was observed in spring and early winter in 1991 and only in early winter in 1992. The number of patients with RSV infection from April 1991 to March 1992 was greater than that from April 1992 to March 1993. In contrast with RSV infection, the epidemic of Mycoplasma pneumoniae infection was observed in 1992. We speculated that the RSV and Mycoplasma pneumoniae infections might interfere with each other.

Adolescent↗