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PubMedDate not supplied

Esophagitis and findings of long-term esophageal pH recording in children with repeated lower respiratory tract symptoms.

Esophagoscopy was performed on 116 children with recurrent lower respiratory tract symptoms; esophagitis of various degrees was detected in 45% of the cases. The presence of verified esophagitis correlated with endoscopic findings of bile-stained gastric contents, suggesting a role of bile reflux in the pathogenesis. Esophageal pH recordings covering an 18-24-h period were performed on 22 patients with esophagitis and 19 patients without esophagitis. Gastroesophageal reflux (GER) during the sleeping period was detected in 95% of children with esophagitis, as compared to 42% in children with no esophagitis (p less than 0.001). The percentage of time with esophageal pH below 4 of the total registration time was significantly greater (p less than 0.05) in children with esophagitis (9.5%) than in those with no esophagitis (4.0%)--the difference being due to a greater share of nocturnal GER of the recording time. These criteria could be applied to a search for clinically significant GER in children with recurrent lower respiratory tract symptoms and to select patients for esophagoscopy.

Adolescent↗

PubMedDate not supplied

Pain catastrophizing and symptom severity during upper respiratory tract illness.

OBJECTIVES: The present study examined the relation of pain catastrophizing to the severity of upper respiratory tract illness. MATERIALS AND METHODS: Participants included 50 adults (35 female subjects, 15 male) who were self-diagnosed with upper respiratory tract illness and who agreed to complete a diary of symptoms for 7 days. Illness symptoms were grouped into three categories: pain-related, constitutional, and respiratory symptoms. RESULTS: Results showed that pain catastrophizing was associated with symptom number and symptom severity in all three categories of symptoms. The rumination subscale of the Pain Catastrophizing Scale showed the strongest relations with illness severity. The relation between pain catastrophizing and illness severity remained significant even when controlling for initial symptom severity, duration of the symptoms before the study period, and depression. DISCUSSION: The results provide the preliminary evidence that the influence of pain catastrophizing may not be restricted to pain-specific domains. The data also provide some support for the view that the excessive focus on bodily sensations may account for more severe symptoms.

Adolescent↗

PubMed1994

Management of upper respiratory tract infections in Dutch family practice.

BACKGROUND: Family physicians vary in their management of upper respiratory tract infections (URTIs), especially regarding prescription of antimicrobial drugs and patient referral. This study was designed to provide insight into this variation in the management of URTI. METHODS: A secondary data analysis of a nationwide study of morbidity and interventions regarding the management of cases of acute otitis media, otitis media with effusion, acute upper respiratory tract infections (acute URTIs), sinusitis, and acute tonsillitis was performed. One hundred sixty-one Dutch family physicians and 335,000 patients were included in the study. RESULTS: About 10% of all first contacts in this study were house calls, which are most often made to patients in the youngest and oldest age categories. In one third of all first contacts, an antimicrobial drug was prescribed, most frequently for sinusitis (72%) and acute tonsillitis (74%), much less frequently for otitis media and acute URTI. Doxycycline and amoxicillin were prescribed most frequently; two thirds of all antimicrobial prescriptions for the first contact were for one of these two drugs. In 1% of all first contacts and 6% of repeat contacts, patients with URTI were referred to a specialist. CONCLUSIONS: Compared with physicians in other countries, Dutch family physicians show a relatively restrictive and selective prescription behavior in dealing with URTI. This may be why the Netherlands has one of the lowest reported levels of antibiotic resistance. House calls are still important in Dutch family practice.

Adult↗

PubMed2001

[A study on the relationship between respiratory tract viruses antigen in peripheral blood mononuclear cells and their antibody from children with steroid-sensitive and simple nephrotic syndrome].

OBJECTIVE: To explore whether respiratory tract viruses infection was involved in the pathogenesis of sterioid-senstive and simple nephrotic syndrome(SSSNS). METHODS: Using APAAP and ELISA, the authors assayed the expression of respiratory tract viruses antigen in peripheral blood mononuclear cells (PBMC) and the production of viruses antibody in serum from 20 cases of children with steroid-sensitive and simple nephrotic syndrome. RESULTS: The positive rate of viruses in the active stage group of SSSNS children increased (P < 0.05), compared with that in the remission group and the healthy control group. The positive rate of virus detection in SSSNS children was closely related with the quantity of urinary protein(P < 0.05). The positive rate of virus detection in the group with urinary protein > or = 50 mg/(kg.d) was higher than that in the group with urinary protein < 50 mg/(kg.d). CONCLUSION: The onset of SSSNS may be related to the infection of respiratory tract viruses.

Antibodies, Viral↗

PubMed1995

[Evaluation of conventional and new generation tests for testing the humeral response to Mycoplasma pneumoniae antigens in natural infections in humans. II. Occurrence and level of mycoplasma antibodies in patients with respiratory tract infections].

The aim of the study was to observe the frequency of occurrence of mycoplasmal antibodies detected by the complement fixation test (CFT), immunoelectroprecipitation test (IEPT) and ELISA in selected groups of patients with respiratory tract infections and to determine the dependence of these antibodies on the age of patients and length of illness. 521 serum samples collected from 404 persons were examined; 378 samples were obtained from 276 patients with pneumonia and 143 from 128 patients with upper respiratory tract infections. Additionally, serum samples from 50 patients with B. pertussis were investigated in this section of the study as a control test to demonstrate the specificity of the tests. It was established that in patients with pneumonia mycoplasmal antibodies are, as a rule, detected in much higher titers than in patients with upper respiratory tract infections. On with age, the level of mycoplasmal antibodies detected in all the three tests rose in the examined patients. In the highest titers antibodies against M. pneumoniae were detected in adults within the age 21-50. As a rule mycoplasmal IgM antibodies reached a level 2-3 times higher than IgG antibodies. It was also shown that already during the first week of illness antibodies against M. pneumoniae determined by the CFT, IEPT and ELISA in the sera of the examined persons are higher than the level known to be diagnostically significant. During the second week of illness IgA and IgM antibodies have a particularly high titer while the growth of titer of IgG antibodies is relatively small. A very high level of IgM, along with progressive growth of IgG antibodies and the related gradual decrease of the index value IgM/IgG, was observed in the serum of patients up to the 4th week of illness. In some cases, in titer known to be diagnostically significant, this high level was present even many months after the appearance of disease symptoms. Antibodies against M. pneumoniae in class of immunoglobulin A disappeared the fastest. Thus it is believed that demonstrating their characteristics dynamics or detecting these antibodies in the patient's serum in the titer assumed to be diagnostically significant can indicate an acute stage of illness.

Adolescent↗

PubMed2004

Suppression of serum antibody responses by pertussis toxin after respiratory tract colonization by Bordetella pertussis and identification of an immunodominant lipoprotein.

Pertussis toxin (PT), a virulence factor secreted by Bordetella pertussis, contributes to respiratory tract infection and disease caused by this pathogen. By comparing a wild-type (WT) B. pertussis strain to a mutant strain with an in-frame deletion of the ptx genes encoding PT (DeltaPT), we recently found that the lack of PT confers a significant defect in respiratory tract colonization in mice after intranasal inoculation. In this study, we analyzed serum antibody responses in mice infected with the WT or DeltaPT strain and found that infection with the DeltaPT strain elicited greater responses to several B. pertussis antigens than did infection with the WT, despite the lower colonization level achieved by the DeltaPT strain. The same enhanced antibody response was observed after infection with a strain expressing an enzymatically inactive PT; but this response was not observed after infection with B. pertussis mutant strains lacking filamentous hemagglutinin or adenylate cyclase toxin, nor when purified PT was administered with the DeltaPT inoculum, indicating a specific role for PT activity in this immunosuppressive effect. In particular, there were consistent strong serum antibody responses to one or more low-molecular-weight antigens after infection with the DeltaPT strain. These antigens were Bvg independent, membrane localized, and also expressed by the closely related pathogens Bordetella parapertussis and Bordetella bronchiseptica. Two-dimensional gel electrophoresis and mass spectrometry were used to identify one of the immunodominant low-molecular-weight antigens as a protein with significant sequence homology to peptidoglycan-associated lipoprotein in several other gram-negative bacterial species. However, a serum antibody response to this protein alone did not protect mice against respiratory tract infection by B. pertussis.

Amino Acid Sequence↗

PubMedDate not supplied

Psychosocial stress and susceptibility to upper respiratory tract illness in an adult population sample.

OBJECTIVE: To assess the influence of life event stress and hassles, and the moderating effects of psychological coping style, social support, and family environment, on susceptibility to upper respiratory tract infectious illness. METHOD: One hundred seven adults aged 18 to 65 years took part in a 15-week study. Measures of life event stress were obtained for the 12 months preceding the study and for the study period itself, and social support, information seeking and avoidant coping styles, and family environment were assessed. Hassles and perceived stress were measured weekly, whereas dysphoric mood and changes in personal health practices (smoking, alcohol consumption, exercise, and sleep patterns) were assessed at three weekly intervals. Episodes of upper respiratory tract infectious illness were verified by clinical examination. RESULTS: During the study period, 29 individuals experienced at least one clinically verified episode of upper respiratory tract illness. There were no differences in cigarette smoking, sleep habits, or exercise between those who did and did not become ill but alcohol consumption was lower among those who experienced verified episodes. Risk of infectious illness was greater in those who experienced high life event stress both before and during the study period, but the impact of life events was buffered by an avoidant coping style. Strict family organization was associated with illness risk. The three weeks preceding illness onset were characterised by high levels of perceived stress, but also by a decrease in the number of hassles reported. CONCLUSIONS: Results suggest that under naturalistic conditions, the influence of stressful experience on risk of infectious illness is moderated by psychosocial resources. Variations in personal health practices do not seem to be responsible.

Adaptation, Psychological↗

PubMed1991

[Serum sensitivity of Pseudomonas aeruginosa isolated from sputum as a virulence factor in the lower respiratory tract].

To elucidate the clinical significance of serum-sensitivity of respiratory pathogenic Pseudomonas aeruginosa (P. aeruginosa) strains, we examined serum-sensitivity of P. aeruginosa isolated from 16 patients with lower respiratory tract infections and clinical backgrounds of these patients. We also evaluated the virulence of four serum-resistant and four serum-sensitive P. aeruginosa strains in murine pneumonia model induced by intratracheal challenge, and the silver-stained profiles of purified lipopolysaccharide (LPS) from these strains. Serum-sensitive strains were isolated only from patients with chronic bronchitis, bronchiectasis, and diffuse panbronchiolitis colonized with P. aeruginosa, and rarely caused pneumonias, while serum-resistant strains caused pneumonias in some cases. Intratracheal challenge of mice with 5 x 10(7) cfu per mouse of a serum resistant strain caused fatal hemorrhagic pneumonia with bacteremia. In contrast, the same dose of a serum-sensitive strain provided non-fatal pneumonia without bacteremia. LD50 of serum-sensitive strains in a murine model of P. aeruginosa pneumonia were at least 2-10 times higher than those of serum-resistant strain. The LPS profiles of two serum-resistant strains and one serum-sensitive strain showed ladder-like patterns. The similar analysis demonstrated that one serum-sensitive strain was lack of ladder-like patterns. These data support that serum-sensitive P. aeruginosa strains are less virulent than serum-resistant P. aeruginosa strains in the lower respiratory tract, and serum sensitivity of P. aeruginosa strains is determined by the structure of the O-side chain of LPS; either lack of the O-side chain or the presence of sparse O-side chain.

Animals↗

PubMed1997

Economic analysis of treatment with roxithromycin in comparison with erythromycin in patients with lower respiratory tract infections.

A number of new antibiotics have lately become available for treatment of lower respiratory tract infections in out-patients. The new drugs are generally more expensive than the older ones, which might be justified by better effects, improved safety, or by other advantages. In this study, a retrospective economic analysis has been made using data from a previous trial comparing a new macrolide, roxithromycin, with an older 1, erythromycin stearate in the treatment of lower respiratory tract infections. The trial was multicentre, double blind, randomized and comparative. There were no significant differences in efficacy between treatments, although the cure rate was higher for roxithromycin, 85% vs 79% for erythromycin. 20/39 of the erythromycin-treated patients reported adverse events, vs 7/40 roxithromycin-treated subjects, a highly significant difference. More detailed information was obtained by reviewing the medical records of the participants, and from questionnaires distributed to the 3 centres that had included patients in the trial. Additional visits were found necessary for 4 patients treated with erythromycin and for 1 using roxithromycin. Using the healing rates in the present investigation, and including costs for initial drug treatments, second consultations, and failed therapy, average cost-effectiveness (SEK/patient cured) was 409 for roxithromycin-treated patients, and 488 for erythromycin-treated. Roxithromycin should then be cheaper than erythromycin stearate. With the same healing rate, roxithromycin would be less cost-effective, but indirect costs and effects on quality of life are not then taken into account.

Anti-Bacterial Agents↗

PubMed2004

Human papillomavirus DNA presence of the upper respiratory tract mucosa of healthy children.

The papillomaviruses are a group of small DNA (8 kbp) viruses which induce papillomas in human and animals. Most of them can also transform epithelial cells of human and other vertebrates. Examinations of children with Recurrent Respiratory Papillomatosis (RRP), using PCR method with specific primers, revealed HPV type 6 or/and 11 in 98%-100% tissue samples. Little is known about HPV infection in upper respiratory tract of healthy children. The group of 201 healthy children (from 3 to 10 years old) was laryngologically examined. The smears from noses and throats were studied for the presence of HPV viruses DNA. PCR was performed as described by Tucker et al. 28.8% of children from the study group were HPV positive. The presence of HPV in respiratory tract in children is relatively high. "High risk" HPV are not observed in the respiratory tract in children. The Human Papillomavirus in children may be transmitted by direct contacts.

Carrier State↗

PubMed1999

A comparison of model-building strategies for lower respiratory tract infection in long-term care.

Five strategies for creating predictive models of lower respiratory tract infection in residents of long-term care facilities were compared. A linear judgment model was derived by administering clinical vignettes to physicians who indicated the risk of infection based on the presence or absence of five predictor variables. A model based on physician consensus was created using the same variables. Three models based on empirical data (logistic regression, proportional hazards, and recursive partitioning) were created from a "derivation" sample of data from a cohort study of lower respiratory tract infections in nursing homes using the five predictor variables. All models were applied to a validation set and compared using receiver operating characteristic (ROC) curves. The data-derived and consensus models showed the highest discriminative ability while the linear judgment model showed inferior performance.

Canada↗

PubMed1997

Prospective case-control study of role of infection in patients who reconsult after initial antibiotic treatment for lower respiratory tract infection in primary care.

OBJECTIVE: To assess direct and indirect evidence of active infection which may benefit from further antibiotics in adults who reconsult within 4 weeks of initial antibiotic management of acute lower respiratory tract infection in primary care. DESIGN: Observational study with a nested case-control group. SETTING: Two suburban general practices in Arnold, Nottingham, over 7 winter months. SUBJECTS: 367 adults aged 16 years and over fulfilling a definition of lower respiratory tract infection and treated with antibiotics. 74 (20%) patients who reconsulted within 4 weeks for the same symptoms and 82 "control" patients who did not were investigated in detail at fallow up. MAIN OUTCOME MEASURES: Direct and indirect evidence of active infection at the time of the reconsultation or the follow up visit with the research nurse for the controls. Investigations performed included sputum culture, pneumococcal antigen detection, serial serology for viral and atypical pathogens and C reactive protein, throat swabs for detecting viral and atypical pathogens by culture and polymerase chain reaction, and chest radiographs. RESULTS: Demographic and clinical features of the groups were similar. Two thirds of the 74 patients who reconsulted received another antibiotic because the general practitioner suspected continuing infection. Any evidence of infection warranting antibiotic treatment was uncommon at reconsultation. The findings for the two groups were similar for the occurrence of identified pathogens; chest x ray changes of infection (present in 13%); and C reactive protein concentrations, which had nearly all fallen towards normal. Only three patients in the reconsultation group had concentrations > or = 40 mg/l. Pathogens identified at follow up in the 156 patients in both groups included ampicillin sensitive bacteria in six. Atypical infections diagnosed in 27 (Chlamydia pneumoniae in 22) and viral infections in 54 had probably been present at the initial presentation. CONCLUSION: Our study suggests that active infection, which may benefit from further antibiotics, is uncommon in patients who reconsult after a lower respiratory tract infection, and a repeat antibiotic prescription should be the exception rather than the rule. Other factors, such as patients' perception of their illness, may be more important than disease and infection in their decision to reconsult.

Adolescent↗

PubMed1979

Neutralizing antibody to bovine adenovirus serotype 3 in healthy cattle and cattle with respiratory tract disease.

A serosurvey of healthy cattle for the presence of serum-neutralizing antibody to bovine adenovirus serotype 3 (BAV-3) established the widespread prevalence of this agent in Iowa cattle. Of the animals studied, 19.1% (involving 157 calves that represented 40 outbreaks (herds) of respiratory tract disease) seroconverted to BAV-3. This pathogen was implicated serologically as being involved in the cause of respiratory tract disease in six herds. Bovine adenovirus serotype 3 was isolated from cattle in two of these herds. Based on seroconversion and lack of isolation of other viral agents, it appeared that BAV-3 could have been the sole virus involved in the respiratory tract disease in one of these two herds. In another herd, seroconversion was observed only to BAV-3, but other viral agents as well as BAV-3 were isolated. The remaining four herds presented a problem because the cattle seroconverted to more than one agent and additional viral agents were isolated from some animals. Whether the disease manifestations observed in these six herds were due solely or in part to BAV-3 can only be speculated. Cattle are capable of undergoing a natural infection, as indicated by seroconversion, in the absence of overt clinical signs of illness. It appears that maternal (passive) antibody decreases to a point at which infection by this virus becomes possible and an active immune response occurs.

Adenoviridae↗

PubMed1999

Clinical and epidemiological aspects of respiratory syncytial virus lower respiratory tract infections.

This paper has analyzed respiratory syncytial virus lower respiratory tract infections in 201 hospitalized children. In children with wheezing, erythrocyte sedimentation rate (ESR) was significantly higher in those with pneumonia than with syndroma pertussis, while the white blood cell (WBC) count was significantly lower in patients with bronchitis than in those with bronchiolitis and syndroma pertussis. Bronchodilatators were applied in 75.6% and corticosteroids in 20% of patients. Ten patients were ventilated. Fatal disease outcome was observed in one infant. Twelve consecutive-year study of respiratory syncytial virus (RSV) infections showed that 27.3% of these diseases were bronchiolitis and pneumonia.

Blood Sedimentation↗

PubMed1995

Phagocytosis and oxidative burst of granulocytes in the upper respiratory tract in chronic and acute inflammation.

Acute diseases and chronic conditions may be associated with altered neutrophil functions. The aim of this investigation was to study the number and function of granulocytes in the upper respiratory tract in acute and chronic airway inflammation. The 136 participating subjects were assigned to 6 groups; group 1: controls; group 2: smokers, < 10 cigarettes/day; group 3: smokers, > 10 cigarettes/day; group 4: patients with allergic rhinitis; group 5: patients with obstructive sleep apnea; group 6: patients with acute viral upper respiratory tract infection. Whole blood and nasal lavage fluid were obtained and a cell count was performed. Phagocytosis of opsonized bacteria and the oxidative burst was measured. Total cell counts and absolute number of neutrophils in nasal lavage (NAL), but not in blood, were elevated in all groups compared to controls. Highest increases of neutrophils were observed in group 4 (7-fold) and group 6 (25-fold), p < .01. Phagocytosis and oxidative burst of granulocytes recovered by NAL were found to be increased in group 4 (25% and 15%, respectively) and group 6 (35% and 21%) only, but decreased in the other groups. We conclude that conditions leading to acute or chronic inflammation in the upper respiratory tract are associated with altered functions of granulocytes recovered by NAL but not blood, suggesting local modulating factors. We speculate that chronic inflammation, in contrast to acute conditions, is associated with impaired granulocyte function.

Adult↗

PubMed2000

Effects of tilmicosin treatment on Pasteurella haemolytica organisms in nasal secretion specimens of calves with respiratory tract disease.

OBJECTIVE: To determine the effect of tilmicosin treatment on number of Pasteurella haemolytica (PH) organisms in nasal secretion specimens of calves with respiratory tract disease. ANIMALS: 206 British mixed-breed beef calves, 2 to 5 months old. PROCEDURE: In 2 separate studies of outbreaks, calves (study 1, n = 101; study 2, n = 105) that developed respiratory tract disease after transport to a feedlot were treated with tilmicosin. Nasal secretion specimens were examined for PH organisms to determine the status of colonization. RESULTS: In both studies, PH serotypes A1 and A6 were isolated. In study 1, tilmicosin treatment eliminated or markedly reduced the number of PH organisms in calves on days 1, 4, and 5 after treatment. In study 2, tilmicosin treatment eliminated PH organisms in calves on days 1, 2, 5, and 6 after treatment. CONCLUSIONS AND CLINICAL RELEVANCE: Overall, tilmicosin treatment increased the number of culture-positive calves that became culture-negative and decreased the number of culture-negative calves that became culture-positive for up to 6 days after treatment. Tilmicosin treatment decreased the number of PH organisms in nasal secretion specimens, which indicated that fewer PH organisms were available to infect the lungs or to infect other calves. By reducing colonization, prophylactic use of tilmicosin before transport or at the time of arrival at a feedlot is likely to reduce the incidence of acute respiratory tract disease in calves for the initial several days after arrival, which is the period when they are most susceptible to infectious organisms.

Animals↗

PubMed2002

Intra-amniotic endotoxin induces lung maturation by direct effects on the developing respiratory tract in preterm sheep.

OBJECTIVE: Our purpose was to determine whether improved preterm lung function caused by intraamniotic endotoxin treatment requires endotoxin entry into the respiratory tract. STUDY DESIGN: We assessed lung inflammation 2 days after intra-amniotic endotoxin (10 mg, Escherichia coli 055:B5) or saline solution in preterm lambs (123 days' gestation) that had undergone surgery to isolate the gastrointestinal or respiratory systems from the amniotic sac. In other sheep longer-term effects were assessed 7 days after we isolated the fetal respiratory tract and gave endotoxin or saline solution directly to the lungs or into the amniotic sac. We measured pulmonary inflammation, lung function, and surfactant 1 week after treatment (approximately 125 days). RESULTS: Pulmonary inflammation was present after intra-amniotic endotoxin only if there was communication between the respiratory tract and the amniotic sac. Lung function was improved and surfactant was increased only in preterm lambs that received direct pulmonary endotoxin. CONCLUSION: Endotoxin causes functional improvement of the preterm lung by direct effects on the developing respiratory system.

Amnion↗

PubMedDate not supplied

Suppression of immunity to influenza virus infection in the respiratory tract following sleep disturbance.

The extent to which sleep deprivation interferes with immunity in the respiratory tract to influenza virus has been assessed in mice. Mice were orally immunized with influenza virus on two occasions separated by a one week interval and challenged intranasally one week later. Some animals were deprived of sleep for a 7 h period immediately following challenge. Three days after challenge, virus clearance and virus specific antibody were determined in lungs of sleep deprived and normally sleeping mice and the results compared with unimmunized mice subjected to the same protocol. Whereas immunized, normal sleep mice achieved total virus clearance, sleep deprivation in immunized mice completely abrogated this effect such that sleep deprived animals behaved as though they had never been immunized. There was no difference in viral clearance in unimmunized mice whether sleep deprived or not, indicating that sleep deprivation did not itself have a direct effect on viral replication. The data reported here support the concept that sleep is a behavioral state which is essential for optimal immune function in the presence of a respiratory tract pathogen.

Administration, Oral↗