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Evidence of a novel human coronavirus that is associated with respiratory tract disease in infants and young children.

BACKGROUND: The etiological agents responsible for a substantial proportion of respiratory tract diseases have not been identified. We sought to determine whether novel human coronaviruses (HCoVs) are circulating in New Haven, Connecticut, and, if so, whether they are associated with respiratory tract disease in infants and young children. METHODS: We developed a polymerase chain reaction (PCR)-based approach for screening specimens from the respiratory tracts of symptomatic children. PCR probes that target regions of the replicase 1a gene that are conserved among genetically diverse animal CoVs and HCoVs were designed. Using these probes, we identified genomic sequences of a novel HCoV, designated "New Haven coronavirus" (HCoV-NH). Thereafter, we designed specific probes to screen respiratory specimens from children <5 years old for this novel HCoV. Clinical features associated with HCoV-NH infection were identified. RESULTS: Seventy-nine (8.8%) of 895 children tested positive for HCoV-NH. Cough, rhinorrhea, tachypnea, fever, abnormal breath sounds, and hypoxia were the most common findings associated with HCoV-NH infection. Sequence analysis revealed that HCoV-NH is closely related to a novel HCoV recently reported in The Netherlands. CONCLUSIONS: The novel HCoVs identified in New Haven and The Netherlands are similar and likely represent the same species. This newly discovered virus may have worldwide distribution and may account for a significant proportion of respiratory tract disease in infants and young children.

Child, Preschool↗

Antibiotic prophylaxis to reduce respiratory tract infections and mortality in adults receiving intensive care.

BACKGROUND: Pneumonia is an important cause of mortality in intensive care units. The incidence of pneumonia in such patients ranges between 7% and 40%, and the crude mortality from ventilator associated pneumonia may exceed 50%. Although not all deaths in patients with this form of pneumonia are directly attributable to pneumonia, it has been shown to contribute to mortality in intensive care units independently of other factors that are also strongly associated with such deaths. OBJECTIVES: The objective of this review was to assess the effects of antibiotics for preventing respiratory tract infections and overall mortality in adults receiving intensive care. SEARCH STRATEGY: We searched the Cochrane Central Register of Controlled Trials (CENTRAL) (issue 3, 2003), which contains the Acute Respiratory Infections (ARI) Group specialised trials register; MEDLINE (January 1966 to September 2003); EMBASE (January 1990 to September 2003); proceedings of scientific meetings and reference lists of articles from January 1984 to December 2002. We also contacted investigators in the field. SELECTION CRITERIA: Randomised trials of antibiotic prophylaxis for respiratory tract infections and deaths among adult intensive care unit patients. DATA COLLECTION AND ANALYSIS: At least two reviewers independently extracted data and assessed trial quality. MAIN RESULTS: Overall 36 trials involving 6922 people were included. There was variation in the antibiotics used, patient characteristics and risk of respiratory tract infections and mortality in the control groups. In 17 trials (involving 4295 patients) that tested a combination of topical and systemic antibiotic, the average rates of respiratory tract infections and deaths in the control group were 36% and 29% respectively. There was a significant reduction of both respiratory tract infections (odds ratio 0.35, 95% confidence interval 0.29 to 0.41) and total mortality (odds ratio 0.78, 95% confidence interval 0.68 to 0.89) in the treated group. On average 5 patients needed to be treated to prevent one infection and 21 patients to prevent one death. In 17 trials (involving 2664 patients) that tested topical antimicrobials alone (or comparing topical plus systemic versus systemic alone) the rates of respiratory tract infections and deaths in the control groups were 30% and 26% respectively. There was a significant reduction of respiratory tract infections (odds ratio 0.52, 95% confidence interval 0.43 to 0.63) but not in total mortality (odds ratio 0.97, 95% confidence interval 0.81 to 1.16) in the treated group. REVIEWER'S CONCLUSIONS: A combination of topical and systemic prophylactic antibiotics reduces respiratory tract infections and overall mortality in adult patients receiving intensive care. A treatment based on the use of topical prophylaxis alone reduces respiratory infections but not mortality. The risk of occurrence of resistance as a negative consequence of antibiotic use was appropriately explored only in the most recent trial by de Jonge which did not show any such effect.

Adult↗

Cytology of the respiratory tract.

Cytology can be a rewarding diagnostic technique in equine practice. The respiratory tract readily lends itself to sampling for cytologic evaluation from the upper to lower regions of the system. This article discusses preservation and staining techniques that will allow the practitioner to present satisfactory samples to the laboratory. General considerations for cytologic analysis are discussed as well as the specific findings for individual disorders of the respiratory tract. The proper use of cytologic findings in conjunction with other diagnostic techniques for the respiratory tract are also discussed.

Ambulatory Care↗

Relationships among treatment for respiratory tract disease, pulmonary lesions evident at slaughter, and rate of weight gain in feedlot cattle.

OBJECTIVE: To quantify the effects of treatment for clinical respiratory tract disease and pulmonary lesions identified at slaughter on rate of weight gain in feedlot cattle. DESIGN: Prospective longitudinal study. ANIMALS: 469 feedlot steers. PROCEDURE: Clinical respiratory tract disease was monitored between birth and slaughter. Steers were weaned at approximately 6 months old and entered into the feedlot for a mean of 273 days. Mean daily weight gain (MDG) was monitored during the feeding period. Lungs were collected at slaughter and evaluated for gross lesions indicative of active or resolved pneumonia. RESULTS: Mean daily weight gain during the feeding period was 1.30 kg, and ranged from 1.16 to 1.46 kg within individual pens. Thirty-five percent of steers received treatment for respiratory tract disease between birth and slaughter, whereas 72% had pulmonary lesions evident at slaughter. Among steers treated for clinical respiratory tract disease, 78% had pulmonary lesions, whereas 68% of untreated steers had pulmonary lesions. Pulmonary lesions at slaughter were associated (P < 0.01) with a 0.076-kg reduction in MDG during the feeding period. Treatment for clinical disease was not associated with MDG after adjustment for the effect of pulmonary lesions. CLINICAL IMPLICATIONS: Treatment of clinically affected feedlot cattle may be inadequate to prevent significant production losses attributable to respiratory tract disease.

Analysis of Variance↗

Oxyphilic proliferations of the respiratory tract and paranasal sinuses.

Neoplasms of the upper respiratory comprised primarily of eosinophilic cells are, in general, rare, and they include a diverse group of lesions. Low-grade oncocytic neuroendocrine neoplasms (so-called oncocytic carcinoids) can be encountered in several locations throughout the respiratory tract. The oncocytoma and related entities, lesions that presumably arise from minor gland tissue, can likewise be seen from the nasal cavity to the lung; differences in clinical significance may relate to the location of such lesions, and are discussed herein. Granular cell tumor is another entity that can involve both the upper respiratory tract and lungs, and specific features of this lesion in different anatomic sites are highlighted. The oncocytic variant of Schneiderian papilloma is an important nasal lesion to recognize, because of important therapeutic and prognostic implications of that diagnosis. Finally, unique oncocytic variants of glomus tumor and pulmonary alveolar adenoma are discussed, as well as eosinophilic varieties of pulmonary carcinomas and mesotheliomas.

Adenoma↗

Use of fiberoptic bronchoscopy in experimental production of bovine respiratory tract disease.

Fourteen 6-month-old calves were infected with Pasteurella haemolytica or infectious bovine rhinotracheitis (IBR) virus. Four calves were inoculated sequentially with IBR virus followed by P haemolytica at a 5-day interval. Calves were inoculated by allowing them to inhale an aerosol of the organism or by placing an inoculum in the right lung, using fiberoptic bronchoscopy. Clinical signs of infection were recorded, and the calves, if they survived, were killed and necropsied 3 days after inoculation with P haemolytica (or 8 days after inoculation with IBR virus). The extent of pulmonary lesions was determined, and the lower respiratory tract (lungs and lower trachea) was examined for both organisms. Inoculation of the calves by aerosolization with IBR virus alone resulted in mild respiratory tract disease. Mild-to-moderately severe respiratory tract disease developed as a result of sequential inoculations by aerosolization with IBR virus and P haemolytica. However, respiratory tract disease did not develop in calves exposed by aerosol to P haemolytica alone. Large numbers of these organisms were recovered from the lower respiratory tract of the dually inoculated calves, only indicating delayed pulmonary clearance. Mild clinical signs of disease but substantial, though localized, pneumonic lesions developed in calves inoculated with P haemolytica by fiberoptic bronchoscopy. Calves inoculated with IBR virus by the latter procedure developed moderately severe respiratory tract disease involving 25% to 30% of the total lung volume. Lesions occurred mainly in the right lung, but the left lung also had marked lesions in these calves.(ABSTRACT TRUNCATED AT 250 WORDS)

Aerosols↗

[Prevalence of papillomavirus infection among patients with laryngeal papillomatosis and the effects of some risk factors on the persistence of papillomaviruses in the upper respiratory tract].

UNLABELLED: Infection with high-risk human papillomaviruses is a significant risk factor of various benign and malignant human lesions in the upper respiratory tract, skin and the genital tract. The identification of particular human papillomaviruses types is important for identifying patients with premalignant lesions who are at risk of progression to malignancy. Our aim was to establish the prevalence of human papillomaviruses infection in the upper respiratory tract of patients with laryngeal papillomatosis, to identify viral types, to evaluate the relationship between some risk factors and persistence of human papillomaviruses in the upper respiratory tract and to determine the pattern of human papillomaviruses infection. MATERIAL AND METHODS: The group of 36 patients with laryngeal papillomatosis and control group of 108 persons without any complains of respiratory system was examined. Epidemiologic characteristics and objective data were analyzed and routine laryngological examination was performed. Pharyngeal swabs of all persons and laryngeal biopsies of 17 patients were taken and analyzed for the presence of human papillomaviruses DNA. Viral typing using the polymerase chain reaction was performed. RESULTS: Human papillomaviruses DNA was detected in all except one case of laryngeal papillomatosis; then only 23.15% of persons without complaints of respiratory system were found human papillomaviruses positive. Human papillomaviruses 6, 11 types were predominant (in 88.9% of patients and 19.4% of persons from control group). High-risk human papillomaviruses were detected in 52.78% of laryngeal papillomatosis cases and in 9.26% of control cases. Risk factors were noted statistically significantly more often in human papillomaviruses positive cases. CONCLUSIONS: The prevalence of human papillomaviruses infection in the upper respiratory tract of patients with laryngeal papillomatosis is high; human papillomaviruses 6, 11 types are predominant. High-risk human papillomaviruses were noted statistically significantly more often in the group of patients with laryngeal papillomatosis. Inclination to diseases of respiratory system, dental caries, smoking, low living standard are statistically significantly related to human papillomaviruses persistence in the upper respiratory tract.

Adolescent↗

A study of human respiratory tract chlamydial infections in Cambridgeshire 1986-88.

Human respiratory tract chlamydial infections have been studied in Cambridgeshire for many years, but until recently we have been unable to distinguish between infection with Chlamydia psittaci or Chlamydia pneumoniae (TWAR). In this study, we have employed the micro-immunofluorescence (micro-IF) test for this purpose and to look for the relative incidence of C. psittaci and C. pneumoniae infections in Cambridgeshire. Among 50 patients with community-acquired respiratory tract symptoms whose serum samples had Chlamydia complement fixation test titres greater than or equal to 64, 25 had evidence of recent C. psittaci or C. pneumoniae infection. Nineteen (76%) of the 25 patients had evidence of recent C. psittaci infection and of these 16 (84%) had recently had contact with birds. Six patients (24%) had evidence of recent C. pneumoniae infection, and of these, only two (33%) had recently had contact with birds. While C. psittaci was grown from several of the birds associated with human C. psittaci infection, it was not cultured from any of the birds in contact with the two human C. pneumoniae cases.

Adult↗

Detection of Mycoplasma fermentans in broncho-alveolar lavage fluid specimens from AIDS patients with lower respiratory tract infection.

OBJECTIVE: To investigate the role of Mycoplasma fermentans in lower respiratory tract disease of HIV-positive patients. METHODS: A polymerase chain reaction (PCR) assay was used to detect M. fermentans in broncho-alveolar lavage (BAL) fluid and peripheral blood mononuclear cells (PBMCs) collected from 78 hospitalized HIV-positive patients with lower respiratory tract disease (the index group). BAL specimens were also assessed from two control groups; 25 HIV-positive patients without respiratory symptoms and 46 patients with a respiratory illness who did not have risk factors for HIV. RESULTS: Seventy-one (91%) of the 78 patients who comprised the index group had AIDS. Sixty-one patients provided BAL and PBMC specimens; 16 provided a BAL specimen and one only a PBMC specimen; 15 (25%) of the 61 patients had M. fermentans positive BAL fluid, of whom 10 (67%) also had a positive PBMC specimen. In contrast, of the 46 patients who had a negative BAL fluid, only three (6.4%) had a positive PBMC sample (P < 0.00001 Fisher's exact test). Overall, 21 (27%) of 77 patients had M. fermentans positive BAL fluid. Of these positive patients, 16 also had another microorganism in the BAL fluid and for five patients M. fermentans was detected alone. Compared with patients in the index group, none of the 46 BAL fluid specimens from patients at low risk of HIV infection was M. fermentans positive (P < 0.001, chi2 15.13). Two (8%) of the 25 HIV-positive patients without respiratory symptoms had a M. fermentans positive BAL fluid, positivity that was also statistically different from the index group (P = 0.045, chi2 4.01). CONCLUSIONS: M. fermentans frequently invades the lower respiratory tract of AIDS patients as an opportunist and may cause disease in some.

AIDS-Related Opportunistic Infections↗

PCR detection of viral nucleic acid in fatal asthma: is the lower respiratory tract a reservoir for common viruses?

BACKGROUND: There is indirect evidence implicating viral respiratory tract infections in the pathogenesis of fatal asthma. However, it is unknown whether viruses are present within the lower respiratory tract in fatal asthma. OBJECTIVES: To apply a nine-virus polymerase chain reaction (PCR) panel to postmortem specimens of lower airway secretions and compare the prevalence of viral nucleic acid among patients who died of asthma, asthmatic patients who died of other causes and persons who died without lung disease. PATIENTS AND METHODS: Postmortem specimens of lower airway secretions from patients who died of asthma (fatal asthma [n=10]), asthmatic patients who died of other causes (n=4) and nonasthma controls (n=6) underwent PCR for nine common respiratory viruses. The prevalence of each virus was compared among the three groups. RESULTS: PCR was positive for at least one virus in 19 of 20 cases, and multiple viruses were detected in 14 of 20 cases. The prevalence of each virus was similar in the three groups studied. CONCLUSIONS: In fatal asthma, lower airway secretions do not show a specific pattern of viral nucleic acid. Intriguingly, these results suggest that the lower respiratory tract may act as a potential reservoir for common respiratory viruses.

Adenoviridae↗

Views on respiratory tract symptoms and antibiotics of Dutch general practitioners, practice staff and patients.

OBJECTIVES: To explore views on respiratory tract symptoms (cough, sore throat and earache) and antibiotics of GPs, practice staff, and patients. METHODS: In a nationwide study, 181 GPs, 204 practice staff members and 1250 patients from 90 practices participated by answering 14 items relating to views on respiratory tract symptoms and antibiotics in a written questionnaire. Differences in means were compared. RESULTS: Patients more than GPs endorsed the seriousness of respiratory tract symptoms, the need to consult a GP, the need to prescribe antibiotics, and the ability of antibiotics to speed up recovery. GPs were more than patients convinced of the self-limiting character of respiratory tract symptoms and of the fact that antibiotics have side effects. Practice staff took a middle ground in most of these views. CONCLUSIONS: Differences between GPs, practice staff and patients must be taken into account when exploring patients' complaints and advising on treatment. Education and knowledge programmes for practice staff might be advocated.

Adult↗

Chlamydia pneumoniae in children with acute respiratory tract infections.

Children seeking medical attention for acute respiratory tract infections were investigated for evidence of Chlamydia pneumoniae infection. Blood samples were obtained from 367 children. Nasopharyngeal or throat swabs for PCR analysis (polymerase chain reaction) were taken from 360 children. Serology was found to be useful for diagnosis of infection only in children aged > 5 y. Using PCR, a prevalence of 8 and 10% of C. pneumoniae was found in male and female children aged < 2 y; 17 and 19%, respectively, in the age group 2-4 y and 32 and 21%, respectively, in the age group 5-16 y. We conclude that Chlamydia pneumoniae is a common finding in young children with respiratory tract infections. Younger children were more often found to have a moderate disease, but may have been ill for a long period.

Acute Disease↗

Clinical and microbiological evaluation of pefloxacin in lower respiratory tract infections.

Patients with Gram-negative lower respiratory tract infections (acute exacerbation of chronic bronchitis (n = 23), pneumonia (n = 4), and bronchiectasis (n = 5) were treated with pefloxacin, 400 mg twice daily, given either intravenously or orally. Symptoms, signs and sputum volume and colour were monitored daily. Chest X-rays, sputum culture and Gram-stain examinations were carried out on days 1 and 5, and immediately after the end of the treatment. There was a clinical improvement, as indicated by the incidence of cough, dyspnoea and rales, and by sputum volume and colour in 31 patients (97%). Microbiological improvement, as indicated by the complete elimination of sputum pathogens and pus cells, was achieved in 28 of the patients (88%). In one patient, an adverse effect, renal failure, occurred. These results suggest that pefloxacin is both clinically and microbiologically effective for the treatment of Gram-negative lower respiratory tract infections.

Acinetobacter Infections↗

Herpes simplex virus infection of the neonatal respiratory tract.

Three patients with neonatal herpes simplex virus (HSV) infection with upper or lower respiratory tract involvement are described. In all three patients, fever and respiratory tract symptoms were the presenting features and occurred in the absence of mucocutaneous lesions or maternal history of HSV Infection. In none of the children was HSV Infection considered likely at the time viral cultures were obtained. These patients demonstrate the need for consideration of HSV in the evaluation of neonatal respiratory tract disease, particularly if it is accompanied by fever and presents after the first several days of life.

Female↗

Mucosal immunology of the upper respiratory tract.

The palatine tonsils and nasopharyngeal adenoids represent the predominant immunocompetent tissue of the upper respiratory tract. Its major function is as a first line of defense against viral, bacterial, and food antigens that enter the upper aerodigestive system. Another major function of the tonsils and adenoids is to supply the local mucosal immune system of the upper respiratory tract with dimeric IgA-producing B cells. Secretory IgA has particular hydrophilic properties and is capable of preventing adsorption and penetration of bacteria and/or viruses into the upper respiratory tract mucosa. In addition, the role of the indigenous flora of the upper respiratory tract, particularly the viridans streptococci has been emphasized as providing a valuable source of bacterial interference to the colonization of potential pathogens.

Adenoids↗

Sites and mechanisms for uptake of gases and vapors in the respiratory tract.

Inhalation is a common route by which individuals are exposed to toxicants. The air contains a multitude of gases and vapors that are brought into the respiratory tract with each breath. Depending upon the physical and chemical characteristics of the toxicant, the respiratory tract can be considered as a target organ in addition to a portal of entry. Sufficient information is not always available on the fate or effects of an inhaled gas or vapor. Two physiochemical principles, water solubility and reactivity, can be used to predict the site of uptake of gases and vapors in the respiratory tract and potential mechanisms for reaction with respiratory tract tissue and absorption into the blood. Four model compounds, formaldehyde, ozone, dibasic esters, and butadiene are discussed as examples of how knowledge of aqueous solubility and chemical reactivity can help toxicologists predict sites and mechanisms by which inhaled gases and vapors interact with respiratory tract tissues.

Absorption↗

Immunoglobulin G subclass deficiency in children with recurrent respiratory tract infections.

With monoclonal antibodies serum immunoglobulin G(IgG) subclasses were measured in seventy children aged 2 to 13 years with recurrent respiratory tract infections including upper respiratory tract infections, otitis media, sinusitis, asthmatic bronchitis and pneumonia. 211 healthy, aged-matched children served as control. IgG subclass deficiency was found in 19 out of the 70 patients (27.1%, single IgG1 deficiency in 7, IgG2 deficiency in 4, combined IgG1-IgG3 deficiency in 5, IgG1-IgG2-IgG3-IgG4 deficiency, IgG1-IgG2-IgG4 deficiency and IgG2-IgG4 deficiency each in 1). The incidence of IgG subclass deficiencies was in the sequence as follows: IgG1, 20%; IgG2, 10%; IgG3, 8.6% and IgG4, 4.3%. The results suggest that IgG subclass deficiency indicate a common disorder in children with recurrent respiratory tract infections.

Adolescent↗

[Clinical evaluation of sulbactam/cefoperazone for lower respiratory tract infections. Correlation between the efficacy of sulbactam/cefoperazone and beta-lactamase].

The efficacy and safety of sulbactam/cefoperazone (SBT/CPZ) were evaluated in 42 patients with respiratory tract infections, including pneumonia (29 patients) and lower respiratory tract infections (5 patients). Overall clinical efficacy rates (excellent + good) were 79% in pneumonia and 80% in respiratory tract infections in 34 patients evaluated for clinical efficacy. It was excellent that the clinical efficacy rate was 92% in mild and moderate pneumonia. Pathogens isolated from sputa were 31 strains, including 8 strains of Pseudomonas aeruginosa, 7 of Streptococcus pneumoniae, 3 of Staphylococcus aureus and 3 of Haemophilus influenzae. Since the isolates were eradicated in 18 strains, replaced in 3, unchanged in 2 and unknown in 8, the overall eradication rate was 91%. The eradication rates were 89% in beta-lactamase producing strains and 100% in beta-lactamase positive sputum, and excellent or good in 19 (83%) of 23 patients with beta-lactamase negative sputum. The eradication rate was 88% in 5 patients with beta-lactamase positive sputum. One patient experienced a moderate rash. Abnormal laboratory test values were observed in 10 patients (26.3%), but these abnormalities were mild and transient. These results suggested that SBT/CPZ was effective and safe for the treatment of respiratory tract infections caused by beta-lactamase producing as well as beta-lactamase non-producing bacteria.

Aged↗