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PubMed1995

An outbreak of Burkholderia (formerly Pseudomonas) cepacia respiratory tract colonization and infection associated with nebulized albuterol therapy.

OBJECTIVE: To investigate an outbreak of Burkholderia (formerly Pseudomonas) cepacia respiratory tract colonization and infection in mechanically ventilated patients. DESIGN: A retrospective case-control and bacteriologic study. SETTING: Veterans Affairs medical center. PATIENTS: 42 mechanically ventilated patients who developed respiratory tract colonization or infection with B. cepacia and 135 ventilator-dependent controls who were not colonized and did not develop infections. MEASUREMENTS: Clinical and demographic data; benzalkonium chloride concentrations and pH levels in albuterol sulfate solutions; repetitive-element polymerase chain reaction (PCR)-mediated molecular fingerprinting on eight patient isolates and three environmental B. cepacia isolates that were available for study. RESULTS: 42 patients had B. cepacia respiratory tract colonization or infection. Observation of intensive care unit and respiratory care personnel showed faulty infection control procedures (for example, the same multiple-dose bottle of albuterol was used for many mechanically ventilated patients). More case patients (39 [92.9%]) than controls (95 [70.4%]; P = 0.006) received nebulized albuterol, and case patients (67.5 treatments) received more treatments than controls (18 treatments; P < 0.001). In-use albuterol solutions had pH values that were unstable, and benzalkonium chloride concentrations declined over time to levels capable of supporting bacterial growth. Medication nebulizers and in-use bottles of albuterol harbored B. cepacia. Molecular fingerprints of patient isolates and environmental B. cepacia isolates were identical using repetitive-element PCR. No further isolates of B. cepacia were identified after institution of appropriate infection control procedures. CONCLUSIONS: Multiple-dose medications and reliance on benzalkonium chloride as a medication preservative provide a mechanism for nosocomial spread of microorganisms, particularly if infection control procedures are not carefully followed. Repetitive-element PCR is a useful fingerprinting technique for molecular epidemiologic studies of B. cepacia.

Aged↗

PubMed1994

Piperacillin/tazobactam in the treatment of community-acquired and nosocomial respiratory tract infections: a review.

Investigators assessed the efficacy and safety of piperacillin/tazobactam therapy in a study of patients with community-acquired lower respiratory tract infections and a study of patients with nosocomial, severe lower respiratory tract infections. Piperacillin 4 g/tazobactam 500 mg was given intravenously every 8 h to 193 hospitalized lower respiratory tract infection patients for a minimum of 5 days. There was a favorable response rate of 97% and eradication of the causative pathogen was documented or presumed in 93% of patients. There was a low incidence of adverse experiences and the combination was well tolerated. Seventy-one intensive care patients with severe lung disease received 4 g piperacillin/500 mg tazobactam intravenously every 6 h; afterward they were given amikacin 7.5 mg/kg every 12 h. Minimum duration of treatment was 5 days. Therapy with piperacillin/tazobactam plus amikacin was well-tolerated, produced a 74% favorable clinical response rate, and eradicated the responsible pathogen in 70% of patients.

Adult↗

PubMed1982

Haemophilus influenzae: comparison of respiratory tract isolates with genitourinary tract isolates.

Haemophilus influenzae isolates recovered from the genitourinary (GU) tract were shown to have a significantly different biotype distribution compared with respiratory tract isolates. Biotype IV strains were recovered more commonly from the GU tract, and most strains were non-serotypable. Antibiotic-susceptible strains isolated from the GU tract more frequently harbored plasmids of less than 10 megadaltons than did antibiotic-susceptible respiratory tract strains. One 2.8-megadalton plasmid resident in a GU tract isolate and one 1.8-megadalton plasmid resident in a respiratory tract isolate were shown to be related to the small ampicillin resistance plasmids previously described in H. influenzae, Haemophilus parainfluenzae, Haemophilus ducreyi, and Neisseria gonorrhoeae. This supports the suggestion that these ampicillin resistance plasmids originated by transposition or recombination of the ampicillin transposon (TnA) with cryptic endogenous Haemophilus plasmids.

Anti-Bacterial Agents↗

PubMed1994

Immunocytochemical survey of the neuroepithelial endocrine system in the respiratory tract of the Tokyo salamander, Hynobius nebulosus tokyoensis TAgo.

The epithelial lining of the respiratory tract of urodeles has been shown to harbor an innervated system of neuroepithelial endocrine (NEE) cells. Even between phylogenetically closely related species, large differences have been reported in the appearance and chemical coding of the NEE system. Although urodeles are well suited for the purpose, none of the prior studies have provided an immunocytochemical survey of the NEE system in all parts of the respiratory tract. In the present study, many bioactive substances and a general marker were immunocytochemically demonstrated in serial sections of the entire respiratory tract of the Tokyo salamander, Hynobius nebulosus tokyoensis, a species in which neuroepithelial bodies (NEBs) were previously characterized at the electron microscopic level. In the current study, serotonin-immunoreactive solitary NEE cells were observed in variable numbers in the larynx, in all parts of the trachea, and in areas of the lungs covered with ciliomucous epithelium. Serotonin-containing NEBs, however, were detected in small cranial areas of the lung only. Solitary NEE cells were seen in the trachea and lungs of H. nebulosus tokyoensis by immunocytochemical staining for somatostatin, calcitonin, calcitonin gene-related peptide, and bombesin, but the number, localization, and appearance of the labeled NEE cells differed considerably. Only calcitonin-like immunoreactivity was also noted in some NEB-like cell clusters in the cranial parts of the lungs. Unlike many other vertebrates, neuron specific enolase was found to be a poor marker for the NEE system in the salamander species used in this investigation. It may be concluded that the NEE system of H. nebulosus tokyoensis contains at least five different bioactive substances.(ABSTRACT TRUNCATED AT 250 WORDS)

Animals↗

PubMed2003

Persistent high plasma levels of interleukins 18 and 4 in children with recurrent infections of the upper respiratory tract.

The aim of this study was to examine whether children with recurrent infections of the upper respiratory tract might have alterations in the systemic immune response to viral infections as compared with healthy control children. We quantitated plasma levels of interferon-gamma, interleukin-12, interleukin-18, interleukin-4, lymphocyte subpopulations, serum immunoglobulins, and subclasses of immunoglobulin G in 30 children under the age of 6 years with recurrent infections of the upper respiratory tract, both during the acute phase of the infection and 4 weeks later, when clinical symptoms had resolved, as well as in 20 normal controls. We found elevated levels of immunoglobulin G primarily due to increased levels of immunoglobulin G(1). Moreover, significantly higher levels of interleukin-18 and interleukin-4 were noted during the acute phase of infection among children with an increased incidence of respiratory infections as compared with the controls (P =.022 and P =.0001, respectively), while plasma levels of interferon-gamma and interleukin-12 were significantly lower (P =.034 and P =.0001, respectively) than in controls. We suggest that an imbalance between T-cell helper type-1 and T-cell helper type-2 immune responses might be responsible for the perpetuation of recurrent infections of the upper respiratory tract.

Child, Preschool↗

PubMed1989

Breast feeding and lower respiratory tract illness in the first year of life. Group Health Medical Associates.

OBJECTIVE: To assess the relation between breast feeding and subsequent experience of lower respiratory tract illness. DESIGN: Prospective (from well child visits) and retrospective (from maternal recall) study of breast feeding and prospective assessment by paediatricians of lower respiratory tract illness in infants during first year of life. SETTING: Health maintenance organisation. PARTICIPANTS: Over 1000 infants who were healthy at birth and whose parents used the paediatricians of a local health maintenance organisation. MAIN OUTCOME MEASURES: Duration of breast feeding and type of lower respiratory tract illness (wheezing and non-wheezing) at different age intervals during the first year of life. RESULTS: Breast feeding was associated with a decreased incidence of wheezing illnesses only in the first four months of life. Interactions existed between breast feeding and sharing a room, being Mexican American, and being a boy. Multivariate techniques showed that after controlling for a variety of factors children who received minimal breast milk had a greater risk of early wheezing illnesses; the risk was further increased by simultaneous exposure to sharing a room. CONCLUSION: Breast feeding seems to protect against wheezing respiratory tract illnesses in the first four months of life, particularly when other risk factors are present.

Breast Feeding↗

PubMedDate not supplied

A study of nonbacterial agents of acute lower respiratory tract infection in Thai children.

From January 1986 to December 1987, 596 children less than 5 years of age with lower respiratory tract infection (LRI)--manifested as laryngitis, croup, bronchitis, bronchiolitis, and pneumonia--were studied for evidence of infection with respiratory tract viruses Mycoplasma pneumoniae, and Chlamydia trachomatis. Of the 596 children in the study, 315 were ambulatory and 281 were hospitalized. Virologic studies included isolation and rapid diagnosis of virus from specimens of nasopharyngeal aspirate (NPA) and serologic studies of blood samples. Cultures of NPA for C. trachomatis were performed for children less than 6 months of age who had pneumonia. Of the LRI cases, 45% were associated with viral infections of the respiratory tract and 12.1% were associated with C. trachomatis. Respiratory syncytial virus (RSV) accounted for 45.2% of infections with viral agents and was associated with acute bronchitis, acute bronchiolitis, and pneumonia. Parainfluenza type 3 virus was the most common virus found in conjunction with laryngitis and croup. The incidence of infections due to RSV peaked in July and August, while that of infections due to parainfluenza viruses peaked in February and March; influenza viruses and adenoviruses were isolated throughout the year.

Acute Disease↗

PubMed1994

Management of upper respiratory tract infections by telephone.

We surveyed Utah general internists (N = 134) regarding their attitudes toward and practices associated with telephone management of upper respiratory tract infections. The questionnaire contained 3 case vignettes--viral upper respiratory tract infection, streptococcal pharyngitis, and acute infectious epiglottitis--and a series of questions were asked about telephone diagnosis, management preferences (clinic versus telephone), and telephone management practices. The 53 respondents (40%) were able to make important diagnostic distinctions about upper respiratory tract infections from a written vignette. As the likelihood of a complicated or serious condition increased, patients would be appropriately triaged for clinical evaluation. Most internists would make a written record of the telephone conversation. Only 1 internist of the 53 would charge for telephone management.

Acute Disease↗

PubMed1986

Occurrence, distribution and ontogeny of CGRP immunoreactivity in the rat lower respiratory tract: effect of capsaicin treatment and surgical denervations.

The occurrence and distribution of calcitonin gene-related peptide (CGRP) immunoreactivity in the rat respiratory tract were investigated by means of immunocytochemistry and radioimmunoassay using antibodies raised in rabbits to synthetic rat CGRP. Substantial amounts of CGRP immunoreactivity (range 5-37 pmol/g) were detected in all parts of the respiratory tract, the highest being in the stem bronchus. Gel filtration chromatography of extractable CGRP immunoreactivity revealed one single peak, eluting at the position of synthetic rat CGRP. CGRP immunoreactivity was localized both in mucosal endocrine cells and nerve fibres from the larynx down to the peripheral lung. CGRP-immunoreactive endocrine cells were found singly in trachea and stem bronchi and in groups in intrapulmonary airways. They appeared at a late stage of gestation (17 days), reached a maximum number near term and decreased after birth to maintain a population similar to that of the adult animals by postnatal day 21. Similarly, CGRP-immunoreactive nerve fibres were first identified by day 18 of the gestation period and reached the adult distribution by postnatal day 21. CGRP-immunoreactive nerve fibres were localized among smooth muscle, seromucous glands, beneath and within the epithelium of the airways and around blood vessels. CGRP was also found in sensory ganglia and in motor end plates of the larynx musculature. Neonatal pretreatment with capsaicin caused a marked reduction in CGRP immunoreactivity of nerve fibres in the respiratory tracts as well as a less marked decrease in the population of CGRP-containing endocrine cells of the lung. No change was seen in motor end plates immunostaining. Vagal ligation experiments revealed that CGRP-immunoreactive nerve fibres travelling in the vagus originate mainly from neurons located in the jugular ganglion. Infranodosal right vagal ligation induced a marked loss in CGRP-immunoreactive nerves of the trachea, and of the ipsilateral stem bronchus, but no changes were observed in peripheral lung. By contrast infranodosal left side vagal ligation caused a decrease in CGRP-immunoreactive nerves of the ipsilateral lung and bronchus without affecting the peptide content in the trachea. Left vagal ligation also induced a marked increase in both the intensity of staining and number of CGRP-immunoreactive endocrine cells in the lung. We conclude that CGRP immunoreactivity is localized in both nerve fibres and endocrine cells and is associated principally with the afferent (sensory) innervation of the respiratory tract.(ABSTRACT TRUNCATED AT 400 WORDS)

Animals↗

PubMed2005

Structure of the respiratory tract of the red-bellied newt Cynops pyrrhogaster, with reference to serotonin-positive neuroepithelial endocrine cells.

To investigate the distribution of serotonin-positive neuroepithelial endocrine (NEE) cells in the respiratory tract of the red-bellied newt Cynops pyrrhogaster, serial sections of the respiratory tract were stained using immunohistochemical methods for serotonin, a periodic acid-Schiff method and hematoxylin-eosin staining. The respiratory tract of the red-bellied newt consisted of a tubular laryngotrachea and two pulmonary sacs. Serotonin-positive solitary NEE cells were distributed widely throughout the ciliomucous epithelium of the laryngotrachea. The innervated clusters of NEE cells, termed neuroepithelial bodies, were rarely found in the caudal portion of the laryngotrachea. The density of NEE cells was high in the middle portion of the laryngotrachea, particularly in the region surrounded by a striated laryngeal sphincter, and the densities were low cranially towards the aditus laryngis and caudally in the pulmonary sacs, the epithelium of which consisted of both ciliomucous epithelial cells and non-ciliated respiratory epithelial cells or pneumocytes. The NEE cells were not observed in the vicinity of non-ciliated respiratory epithelial cells. The morphology and distribution of serotonin-positive NEE cells in the respiratory tract of the red-bellied newt were similar to those described in mammals, including humans. The close localization of NEE cells with ciliary and mucous cells and the distribution of NEE cells in the laryngotrachea suggest that NEE cells play important roles in the defense and repair of the ciliomucous epithelium, such as increasing mucous secretion, ciliary beat frequency and the proliferation of epithelial cells.

Animals↗

PubMed1987

Serum IgG subclasses in patients with an increased susceptibility to respiratory tract infections.

Serum IgG subclass concentrations were assayed in 45 patients with chronic respiratory tract infections and 16 patients with recurrent acute respiratory tract infections. Eleven of these 61 patients, all but one with recurrent acute infections, were IgA-deficient but the remainder had normal or high serum immunoglobulin concentrations. Only 4% of patients with chronic infections were IgG2-deficient. The prevalence of IgG2 deficiency amongst patients with recurrent acute infections was greater (31%), but in most cases this appeared to be due to an association with IgA deficiency. Owing to the limits of assay sensitivity it was not possible to determine whether any patient was IgG4-deficient, but the number of sera with undetectable IgG4 was greater in patients with recurrent acute infections than in controls (37.5% vs 10%, p less than 0.01), although such patients were mainly those with IgA and IgG2 deficiency. None of the patients had IgG1 or IgG3 deficiency; in fact IgG3 concentrations were higher than those of controls in both groups of patients (p less than 0.001) and IgG1 concentrations were higher than those of controls in patients with recurrent infections (p less than 0.01). Thus, unequivocal IgG subclass deficiency is uncommon in non-IgA-deficient patients, but those with IgG2 deficiency may have an immune defect requiring further investigation.

Adult↗

PubMed1998

[Clinical efficacy and safety of spiramycin and clarithromycin in the treatment of outpatients with lower respiratory tract infections].

Macrolide antibiotics have a broad spectrum of activities against the common pathogens responsible for lower respiratory tract infections, therefore for over 40 years they have been useful in treatment of these diseases. The aim of this open randomised multicentre trial is to compare the efficacy and safety of spiramycin, one of the first macrolides, to clarithromycin, a new generation macrolide, in their normal condition of use in patient presenting with acute non-complicated lower respiratory tract infections. 55 adult non-hospitalised patients with clinical diagnosis of bronchitis or pneumonia were randomised to receive either spiramycin 3 MIU twice daily or clarithromycin 500 mg twice daily for 7 or 10 days. For clinical evaluable patients, successful outcome was noted for 96.15% (25/26) spiramycin-treated patients and 96.43% (27/28) clarithromycin-treated patients. Clinically significant improvement in signs and symptoms was comparable between treatment groups. 2 patients in the spiramycin group (7.69%) and 3 in clarithromycin group (10.71%) complained of adverse events which severity was mild or moderate and did not require interruption of conducting antibioticotherapy. Efficacy and safety analysis showed that the two macrolides were equally effective and well-tolerated, at the given doses, for the treatment of lower respiratory tract infections and may play important role in out-patient therapy of these diseases.

Adult↗

PubMed1976

Respiratory tract illness in meat wrappers.

A questionnaire survey was done in 152 Houston supermarkets to assess the prevalence of respiratory tract symptoms in meat wrappers exposed to the thermal decomposition fumes of polyvinyl chloride (PVC) film wrap and in two supermarket control groups (checkers and meat cutters). Meat wrappers had increased respiratory tract symptoms; 12% of meat wrappers who smoked (vs 6% and 2% of controls) and 5% of meat wrappers who did not smoke (vs 0% and 0% of controls) had multiple respiratory tract symptoms. It is probable that a large number of meat wrappers have mild symptoms with some progressing to more severe respiratory impairment or clinical asthma.

Adult↗

PubMedDate not supplied

Acute lower respiratory tract infection due to Chlamydia species in children under five years of age.

BACKGROUND: The contribution of Chlamydia spp in respiratory tract infections in paediatric population from India has not been studied in detail. METHODS: Sixty children under five years of age who were admitted with acute lower respiratory tract infection during a one year period were investigated for Chlamydial aetiology of respiratory infection. Diagnosis was based on antigen detection by direct immunofluorescence (DIF) in throat swab along with anti-Chlamydial immunoglobulin G (IgG) antibody demonstration by solid phase enzyme immunoassay (EIA). RESULTS: Chlamydia spp antigen was detected in seven (11.6%) cases, C. pneumoniae in six (10%) and C. trachoniatis in one (1.6%). Chlamydia spp IgG antibody in serum was demonstrated in 24 (40%) cases, of which C. pneumoniae IgG was denconstrated in 18 (30%) cases. Taking the criteria of antigen detection (n=7) and high IgG antibody titre of > or = 1:512 (n=5) for a positive case, 12 (20%) children were found to be suffering from recent Chlamydial infection. CONCLUSION: Chlamydia spp plays a significant role in respiratory tract infections in Indian paediatric population. Diagnostic procedure like antigen detection in throat swab is rapid, less cumbersome and feasible and should be more widely used along with antibody demonstration to determine the aetiological agent early in the course of illness.

Acute Disease↗

PubMed1984

[Infection causing pathogens in the area of the upper respiratory tract. Bacteriologic diagnosis and chemotherapy from the viewpoint of the bacteriologist].

After a short survey of the indigenous bacterial flora, and of the important bacteria causing infections of the upper respiratory tract, the conditions which are mandatory for proper evaluation of the bacteriological results and which must be observed by the physician in obtaining and forwarding specimens are discussed. Swabs must be sent in preservation media; otherwise the detection rate of viable organisms will fall considerably. Transport should therefore be as rapid as possible. Viral infections often pave the way of infections of the upper respiratory tract. In hospitalised patients however the suppression of the normal flora and selection of resistant strains by antibiotics often play the major role. Chemotherapy should be preceded by bacteriological investigation or, at least, by taking a suitable specimen for the detection of the causal bacteria and determination of their susceptibility to antibiotics. "Blind" therapy will result in 20-30% failures of the treatment. The following questions should be answered before antibiotics are started: Is there really a need for immediate chemotherapy? How likely are the causal bacteria to be sensitive? What defence mechanisms can be expected from the patient? What side effects of the antibiotic must be taken into consideration? The most important infections of the upper respiratory tract, the selection of effective antibiotics and the susceptibility of the more frequent pathogens of this area are also discussed. Finally some aspects of perioperative prophylaxis of infections after surgery of the upper respiratory tract are described.

Abscess↗

PubMed1994

Pseudohypoaldosteronism with increased sweat and saliva electrolyte values and frequent lower respiratory tract infections mimicking cystic fibrosis.

Four patients with severe pseudohypoaldosteronism caused by multiple end-organ resistance to aldosterone had frequently recurring lower respiratory tract infections and persistently elevated sweat and saliva electrolyte values. The increased saliva electrolyte values in these patients probably affect normal mucociliary function in the respiratory tract and facilitate the occurrence of frequent lower respiratory tract involvement. Patients with pseudohypoaldosteronism may require treatment similar to that for cystic fibrosis to prevent long-term respiratory complications.

Aldosterone↗

PubMed1975

[Virus infections of the respiratory tract in childhood (author's transl)].

Comprehensive epidemiological studies revealed that every individual is suffering from a respiratory tract infection in the average 6 times a year. 97% of these are caused by viruses. Identical clinical symptoms may be produced by many different agents, thus the etiology of an illness can only be identified by virus isolation and serological tests. The frequency of isolations is varying in adults and in children as well as in ambulatory and in hospitalized patients. The persistently observed susceptibility for new infections is caused by the great variety of possible etiologic agents especially in upper respiratory infections and the peculiarities of local immunity in the respiratory tract. An influence of chilling could not be demonstrated scientifically in spite of controverse clinical observations. It was proved however that allergic individuals succumb more frequently to viral infections. Overweight in infancy increases susceptibility for bronchitis and bronchiolitis. Superinfections by bacteriae are not rarely complications of viral diseases and antibiotic therapy may become necessary eventually. Leucocytosis and an elevated erythrocyte sedimentation rate are only criteria of limited value to distinguish viral and bacterial infections. Specific virostatic therapy is not possible so far for respiratory tract illnesses, but for prophylaxis of infections with influenza A2 amantadine-HCl may be used. Gammaglobulin has a prophylactic effect as well for certain virus infections but is of little use for antiviral therapy.

Adenoviridae↗

PubMed1984

The distribution and function of peroxidases in the respiratory tract.

Heme-containing peroxidases have been demonstrated both biochemically and cytochemically in a variety of cells that either reside in the respiratory tract or circulate through it via the vasculature. The peroxidases in neutrophils and eosinophils have long been known to function in lung defense through their participation in an antimicrobial system involving hydrogen peroxide and chloride ions. Recent studies indicate that this system is also toxic to tumor cells and, as such, it may have a protective or mitigative effect on tumor formation in the lung. Eosinophil peroxidase may be involved in immediate hypersensitivity reactions in the lung because of its secretory effect on mast cells. Platelets contain peroxidases, but how they function is unknown. Whether peroxidase occurs in lymphocytes is controversial, but until more compelling evidence is presented they should be considered peroxidase-negative. A number of cells indigenous to the respiratory tract contain peroxidase activity, but there is considerable variability among species as to its presence and amount. When careful consideration is given to fixation and incubation conditions, peroxidase can be demonstrated cytochemically in the nuclear envelope and endoplasmic reticulum of some endothelial cells and type II cells of certain rodents, but its physiological role is speculative. The alveolar macrophages of most species possess little or no peroxidase activity apart from catalase which can function as a peroxidase under certain conditions. Mast cells in the respiratory tract contain peroxidase, but it is more easily demonstrated biochemically than cytochemically. The function of mast cell peroxidase is unknown, but two hypotheses worthy of investigation are its possible role in modulation of atopic allergic reactions and involvement in an antitumor defense mechanism similar to that of myeloperoxidase. Peroxidase is most abundant in the secretory cells of the tracheobronchial epithelium and glands where, in a number of species, it is synthesized and secreted as a component of mucus. Its possible contribution to lung defense is discussed in view of its morphologic similarity to the antibacterial peroxidase of milk and saliva. Because of the ease with which peroxidases can be demonstrated cytochemically, it is not surprising that morphologic information regarding their distribution in the respiratory tract has greatly exceeded insights into their functional significance. It is hoped that advancements in cell dissociation and culture, along with biochemical isolation and purification techniques, will lead to definitive conclusions concerning their physiologic roles in lung metabolism and defense.

Basophils↗