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Results for “RESPIRATORY TRACT INFECTIONS”

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At least 19 recordsLinked to original sources

PubMed1997

Dosing of amoxicillin/clavulanate given every 12 hours is as effective as dosing every 8 hours for treatment of lower respiratory tract infection. Lower Respiratory Tract Infection Collaborative Study Group.

In this double-blind study, 557 patients with lower respiratory tract infection were randomly assigned to receive amoxicillin/clavulanate orally either every 12 hours (875/125 mg) or every 8 hours (500/125 mg) for 7-15 days. For the 455 patients evaluable for clinical efficacy at the end of therapy, clinical success was similar in the two groups: 93% and 94% in the 12-hour and 8-hour groups, respectively (P = .42). Bacteriologic success at the end of therapy was also comparable: 97% and 91% in the 12-hour and 8-hour groups, respectively (P = .86). The occurrence of adverse events related to treatment was similar for the two groups, but fewer patients in the 12-hour group reported moderate or severe diarrhea. Amoxicillin/clavulanate (875/125 mg) given every 12 hours is as effective and safe as every-8-hours administration of the combination (500/125 mg) for the treatment of lower respiratory tract infection.

Adolescent↗

PubMed2000

The epidemiology of respiratory tract infections.

Respiratory tract infections (RTIs) are the most common, and potentially most severe, of infections treated by health care practitioners. Lower RTIs along with influenza, are the most common cause of death by infection in the United States. Risk factors for pneumonia and other respiratory tract infections include: extremes of age (very young and elderly), smoking, alcoholism, immunosuppression, and comorbid conditions. The microbial cause of RTIs vary depending on the infection (i.e., pneumonia compared with acute bacterial sinusitis), setting (i.e., community-acquired compared with nosocomial), and other factors. The causative pathogens associated with CAP have changed in prevalence over time. Although Streptococcus pneumoniae remains the most common causative pathogen, a number of newer pathogens, such as Chlamydia pneumoniae and sin nombre virus, have been recognized in recent years. The emerging antimicrobial resistance of respiratory pathogens (most notably S. pneumoniae) has also increased the challenge for appropriate management of RTI. An awareness of the epidemiology and cause of specific respiratory infections should optimize care.

Adolescent↗

PubMedDate not supplied

Efficacy of a polyvalent bacterial lysate in children with recurrent respiratory tract infections.

Respiratory tract infections (RTIs) are the most frequent infections in humans, particularly in children. In addition to intervention, increasing interest is focusing on immunomodulatory therapy for recurrent RTIs, which indicate a reduced defense capacity of the respiratory mucosa. LW 50020, an oral immunomodulator that contains the antigens of seven bacteria common in RTIs, has reduced the number, duration, and severity of RTIs in children and adults. This 56-week placebo-controlled, double-blind study in 188 children investigated whether the efficacy of the standard schedule (immunization cycle + one booster cycle) would be enhanced by additional booster cycles. Efficacy and safety over the long term were also assessed. The rate of infection was reduced by 50% with the standard schedule and could not be further decreased by two consecutive booster cycles. With both schedules, this reduction was sustained during a 28-week treatment-free observation period that followed the 28-week treatment period. The number of adverse drug reactions was low, and all were transient, expected, and nonserious. These results confirm that LW 50020 is an effective and safe strategy for RTIs.

Adjuvants, Immunologic↗

PubMed2005

Appropriate antibiotic therapy for community-acquired respiratory tract infections.

Respiratory tract infections (RTIs) are expensive for MCOs and cause significant morbidity among their members. Although awareness of resistance to antibiotics is increasing, antibiotic selection for community-acquired RTIs remains largely empiric. When making formulary decisions, Pharmacy and Therapeutics Committees may want to consider the spectrum of coverage that an antibiotic provides and its vulnerability to resistance development. Through appropriate formulary management and provider education, MCOs can promote successful clinical and economic outcomes. This article examines the current status of antibiotic therapy for community-acquired RTIs and encourages the incorporation of new parameters into MCO formulary decision processes.

Anti-Bacterial Agents↗

PubMedDate not supplied

Multicenter evaluation of the efficacy and safety of gatifloxacin in Mexican adult outpatients with respiratory tract infections.

Respiratory tract infections (RTIs), the most common indication for outpatient antimicrobial therapy, impose a heavy medical and societal burden and present a difficult therapeutic challenge in the face of increasing pathogen resistance worldwide. Gatifloxacin is a new broad-spectrum fluoroquinolone with excellent activity against prevalent respiratory bacteria, including penicillin-resistant Streptococcus pneumoniae and atypical pathogens. A multicenter, open-label, noncomparative surveillance study carried out in Mexico evaluated the safety and efficacy of oral gatifloxacin 400 mg once daily in 17,923 adult outpatients with community-acquired pneumonia (CAP) (n = 3322), acute exacerbations of chronic bronchitis (AECB) (n = 5885), and acute bacterial sinusitis (n = 8716). Voluntary, unpaid physician participation contributed to an unbiased study design. Physician-assessed global rate of cure or improvement was 96.3%; efficacy was 95.8% in CAP, 96.1% in AECB, and 96.4% in sinusitis. The incidences of relapse (1.5%) and therapeutic failure (0.7%) were low. The most commonly reported adverse events, nausea (2.76%), headache (2.20%), and dizziness (1.33%), were generally mild and self-limited. Oral gatifloxacin 400 mg once daily is effective and safe for patients with CAP, AECB, and acute sinusitis.

Acute Disease↗

PubMed2005

[Immunization and immuno-modulation for prevention of respiratory tract infections].

Respiratory tract infections are a major public health issue. Prevention in high risk populations relies mainly on vaccination against Influenza and S. pneumoniae. Vaccination of health-care workers is highly recommended, to decrease absenteism, but above all to protect high risk patients. New conjugate vaccines have shown their effectiveness in the paediatric population. In patients with chronic bronchitis or COPD, immunomodulatory agents (OM-85 BV) and anti-oxidants (NAC) are probably contributive in decreasing exacerbation rates. Inhaled corticosteroids decrease exacerbations in a well defined group of severe COPD. In patients with diffuse bronchiectasis, the immunomodulatory effect of macrolides, and the use of inhaled corticosteroids should be confirmed by larger clinical investigations.

Humans↗

PubMedDate not supplied

Can antimicrobial activity be sustained? An appraisal of orally administered drugs used for respiratory tract infections.

Respiratory tract infections (RTIs) represent a major cause of illness worldwide. Therefore, it is of great concern that common RTI pathogens have become increasingly resistant to many of the antimicrobial agents used for therapy. For example, Haemophilus influenzae and Moraxella catarrhalis have become resistant to beta-lactam drugs by producing efficient beta-lactamases (> 35 and 90% of strains, respectively). More recently, pneumococci have become more resistant through the mechanism of altered penicillin-binding proteins (PBPs). The rate of penicillin nonsusceptible isolates has risen to > 25% in the United States (1994-1995). It is important to monitor the resistance characteristics of such pathogens and, if possible, to use regionally acquired data to guide empiric selection of therapeutic agents for RTIs. Currently, some antimicrobials remain effective against the majority of these three bacterial species, as exemplified by amoxicillin/clavulanic acid. Furthermore, amoxicillin alone seems to possess greater inhibition than other orally administered beta-lactams at clinically achievable concentrations against pneumococci with altered PBPs. It is critical that steps are taken to limit resistance problems, particularly through; 1) education of prescribers and the public; 2) initiation of the development of novel drugs with alternative modes of action or stability to existing resistance mechanisms; and 3) by continuing to generate quality susceptibility testing data to guide empiric chemotherapy against bacterial pathogens causing RTI.

Administration, Oral↗

PubMed1993

Clinical requirements in the treatment of today's respiratory tract infections.

Respiratory tract infections (RTIs) are among the most frequent infections in man and lower tract infections account substantially for the overall mortality in hospitals. Regarding the etiology of pneumonias, one has to consider different pathogenic mechanisms, age of the patients, underlying diseases, concomitant medications, symptomatologies, seasonal influences, and clinical conditions, e.g. intensive care environment and mechanical ventilation. To optimize the rational management of respiratory infections, identification of the etiologic agent would be desirable. The decision of how to treat is often based on epidemiologic, clinical, and radiological assessments. Epidemiologic studies have shown a pronounced difference in the etiologic spectrum between community- and hospital-acquired RTIs. In community-acquired pneumonias, pneumococci, Haemophilus influenzae, Legionella, Mycoplasma and viruses predominate, whereas in nosocomially acquired pneumonias, Enterobacteriaceae, e.g. Klebsiella, Proteus, Enterobacter as well as Pseudomonas and staphylococci comprise the most frequent isolates. Empirical therapy has to cover all possible etiologic pathogens which most likely cause the infection. In addition, an adequate kinetic profile, e.g. once or twice daily dosing, sufficient pulmonary tissue or fluid penetration, and acceptable tolerance and costs are prerequisites for optimal therapy. Drugs of choice for the treatment of community-acquired pneumonia are aminobenzylpenicillins or macrolides. Oral cephalosporins exhibit excellent activity against many bacterial pathogens of typical community-acquired pneumonia, and are active against beta-lactamase-producing H. influenzae.

Drug Resistance, Microbial↗

PubMed2005

The clinical features of respiratory syncytial virus: lower respiratory tract infection after upper respiratory tract infection due to influenza virus.

BACKGROUND: Respiratory syncytial virus (RSV) and influenza virus are the primary pathogens of respiratory tract infection. However, epidemics of influenza virus infection have been observed to interrupt RSV epidemics (termed an epidemiological interference effect). METHODS: At a clinic in Tsuna county, Hyogo prefecture, Japan, a total of 1262 outpatients under 6 years of age with lower respiratory tract infection due to RSV (RSV-LRTI) and upper respiratory tract infection due to influenza virus (FLU-URTI) in three successive winter seasons (1999-2000, 2000-2001 and 2001-2002) were analyzed. RESULTS: The RSV-LRTI epidemic and FLU-URTI epidemic overlapped in each season, but the RSV-LRTI epidemic peak preceded that of the FLU-URTI epidemic. Epidemiological interference between RSV and influenza virus was observed in the second and third season; the number of patients with RSV-LRTI began to decrease after the start of the FLU-URTI epidemic and recovered to some extent after the FLU-URTI epidemic passed its peak. There were no differences in onset age, male-to-female ratio and severity of RSV-LRTI in outpatients before and after the start of the FLU-URTI epidemic in all the three seasons. CONCLUSION: An epidemiological interference between RSV and influenza virus was observed in Tsuna county in two of the three winter seasons. However, there was no difference between the clinical features of the patients with RSV-LRTI before and after the start of the influenza virus infection epidemic. The data suggest that the clinical severity of RSV infection is not changed by the epidemiological interference effect of influenza virus infection epidemics.

Child, Preschool↗

PubMedDate not supplied

Epidemiology of respiratory syncytial virus in children with lower respiratory tract infection.

Respiratory syncytial virus (RSV) is the most frequent pathogen found in hospitalized young children with lower respiratory tract infection, and the virus is distributed worldwide. Respiratory distress and respiratory failure are caused by RSV in some severe cases. Its appearance always varies every year and depends on differences of latitudes, altitudes and climates. The purpose of this study was to investigate the epidemiology of hospitalized children from a hospital located in northern Taiwan with RSV induced lower respiratory tract infection. This study was conducted from January 2001 to December 2003, and the selected patients were children aged under five and diagnosed with lower respiratory tract infection. The means adopted in this study were analyses of clinical presentations and laboratory tests (including viral identification with either virus culture or RSV antigen rapid test from the nasopharyngeal aspirate). The results showed that 153 children were positive with RSV identification. These cases were diagnosed in clinical practice all year round, and its peak was in spring, especially in March and April. Thirteen percent of all RSV-infected children in this study presented as severe form with respiratory distress and a need of respiratory support. However, none of these cases died from this disease, and all cases recovered without long-term respiratory complication. We concluded that RSV infection was still a common pathogen for young children in northern Taiwan; in addition, March and April were regarded as peak months of epidemic. Patients aged under 12 months or suffered from underlying cardiopulmonary disease were at high risk of getting severe forms of RSV infection.

Cardiovascular Diseases↗

PubMedDate not supplied

[Current approaches to the clinical virologic diagnosis of viral respiratory tract infections].

Respiratory viruses (respiratory syncytial virus, influenza virus type A and B, parainfluenza virus and adenovirus) can cause a wide variety of human disease. Viral respiratory diseases in adults and children cause significant morbidity and mortality. Proper and rapid diagnosis of these etiological agents is necessary for the appropriate use of effective antiviral drugs and to decrease unnecessary antibiotic therapy. Many virology laboratories detect respiratory viruses by inoculating conventional cell culture tubes with respiratory samples and then examining for cytopathic effect or hemadsorption. However, this procedure can require many days or even weeks for viral detection and identification, providing culture results to clinicians in a period of time that may not be clinically useful. Laboratory diagnosis of respiratory virus infections has become easier and more rapid with the use of immunofluorescent antibody tests, shell vial culture methods, and molecular biological assays. In this review article, the specificities and sensitivities of these assays were compared on the basis of recent studies, and the favorable ones for the routine diagnosis were updated.

Adenovirus Infections, Human↗

PubMed2005

Prospective study of the incidence, clinical features, and outcome of symptomatic upper and lower respiratory tract infections by respiratory viruses in adult recipients of hematopoietic stem cell transplants for hematologic malignancies.

Respiratory viruses (RVs) are known to be major causes of morbidity and mortality in recipients of hematopoietic stem cell transplants (HSCTs), but prospective long-term studies are lacking. We prospectively screened all adult HSCT recipients (172 allogeneic [alloHSCT] and 240 autologous [autoHSCT]) who underwent transplantation during a 4-year period (1999 to 2003) for the development of a first episode of symptomatic upper respiratory tract infections and/or lower respiratory tract infections (LRTI) by an RV. RVs studied were influenza A and B viruses (n=39), human respiratory syncytial virus (n=19), human adenoviruses (n=11), human parainfluenza viruses 1 to 3 (n=8), human enteroviruses (n=5), human rhinoviruses (n=3), and the recently discovered human metapneumoviruses (n=19). During the study, 51 and 32 cases of RV symptomatic infections were identified of alloHSCT and autoHSCT recipients (2-year incidence, 29% and 14%, respectively). Risk factors for progression of upper respiratory tract infection to LRTI included severe (<0.2x10(9)/L) and moderate (<0.2x10(9)/L) lymphocytopenia in alloHSCT (P=.02) and autoHSCT (P=.03). Death from LRTI was attributed to an RV in 8 alloHSCT recipients. Symptomatic RV had no effect on 2-year outcomes, with the possible exception of influenza A and B virus infections in autoHSCT: these were associated with nonrelapse mortality (P=.02). In conclusion, this prospective trial allows an estimation of the minimum incidence of a first RV infection in adult HSCT recipients and identifies risk factors for acquisition of an RV infection and progression to LRTI; this should aid in the design of future studies. In addition, human metapneumovirus should be added to the potentially serious causes of RV infections in HSCT.

Adult↗

PubMed1996

Intranasal monoclonal IgA antibody to respiratory syncytial virus protects rhesus monkeys against upper and lower respiratory tract infection.

Respiratory syncytial virus (RSV), the major cause of lower respiratory tract disease in infants, is thought to infect the upper airways before spreading to the lower respiratory tract. A rhesus monkey model of RSV infection after upper airway inoculation was used to test the protective effect of intranasal treatment with HNK20, a mouse monoclonal IgA antibody against RSV F glycoprotein. HNK20 was administered once daily for 2 days before RSV challenge and 4 days after challenge. Treatment with 0.5 mg/kg HNK20 reduced viral shedding in the nose, throat, and lungs by 3-4 log10/mL (P < or = .002). All monkeys developed RSV neutralizing antibody in serum, even in the absence of detectable viral replication. Neutralizing concentrations of monoclonal antibody remained in nasal secretions for > 1 day after treatment. These results suggest that nose-drop application of monoclonal antibody could provide convenient and effective protection against RSV infection in human infants at risk of severe lower respiratory tract disease.

Administration, Intranasal↗

PubMed2005

Intravenous immunoglobulin replacement prevents severe and lower respiratory tract infections, but not upper respiratory tract and non-respiratory infections in common variable immune deficiency.

BACKGROUND: Although the dose of 400 mg/kg body weight intravenous immunoglobulins (IVIG) every 3-4 weeks is now standard for treating patients with common variable immune deficiency, studies demonstrating its long-term benefits over low 200 mg/kg dose and its effects on infectious subsets (upper vs lower respiratory vs non-respiratory infections) are rare. METHODS: All patients from a single center with the diagnosis of common variable immune deficiency and whose clinical chart was available during three successive therapeutic periods [a pre-IVIG replacement period, a low-dose (200 mg/kg every 3 weeks) and a standard-dose replacement period (400 mg/kg every 3 weeks)] were screened retrospectively. RESULTS: Seven patients followed up for a total of 116 patient-years over the three defined periods of observation were recruited. When compared with low-dose therapy, standard-dose intravenous immunoglobulin therapy raised trough IgG levels from 4.3 to 6.5 g/l and significantly decreased the overall frequency of infections, with marked effects on lower respiratory tract and severe infection number. In contrast, non-respiratory and upper respiratory infections were, in comparison, resistant to therapy. CONCLUSIONS: Overall, these data support the use of standard-dose 400 mg/kg intravenous immunoglobulin therapy, despite the high cost, to raise trough IgG levels to 5-7 g/l, but underlines that some categories of infectious events (non-respiratory, upper respiratory) may need parallel surgical or pharmacological approaches to be optimally prevented or treated.

Adult↗

PubMed2004

Evaluation of R-Mix shell vials for the diagnosis of viral respiratory tract infections.

Respiratory viruses cause significant morbidity and mortality. The management of these infections can be improved by a rapid diagnosis and administration of available virus-specific therapy. The goal of this study was to compare R-Mix, an engineered tissue monolayer for rapid shell vial (SV) diagnosis of viral respiratory infections, with conventional tissue culture (TC) and conventional respiratory SV (primary rhesus monkey kidney (RhMK) and Hep2 monolayers). The primary outcome measure was sensitivity for detection of influenza A and B, respiratory syncytial virus, parainfluenza 1-3, and adenovirus. The study was performed in two phases: (1) the three methods were compared using 250 nasal washes from children with lower respiratory tract infections; (2) a modified R-Mix SV harvesting schedule (SV were harvested at 24 and 120 h) was compared with TC and conventional RhMK/Hep2 SV using 311 respiratory specimens. A total of 110 viruses were identified in the first and 55 in the second phase. Diagnostic accuracies of R-Mix harvested at 24, 48, and 120 h were 98%, whereas for TC varied between 99 and 100%, and for RhMK/Hep2 SV between 98 and 99%. Sensitivities of R-Mix harvested at 24, 48, and 120 h were 26, 75, and 47%, respectively, whereas for TC varied between 60 and 94%, and for RhMK/Hep2 SV between 62 and 85%. R-Mix harvested at 48 h represent a valuable substitute for RhMK/Hep2 SV because they have comparable sensitivities and diagnostic accuracies, but R-Mix offers several technical advantages. In contrast, R-Mix harvested at 24h did not seem a very useful diagnostic tool. The utility of R-Mix harvested at 120 h, which accelerated the diagnosis of 16% of positive specimens in study phase 2, needs further investigation.

Adenoviruses, Human↗

PubMed1995

[Respiratory tract infection and respiratory syncytial virus in young infants].

We investigated the role of respiratory syncytial virus (RSV) in respiratory tract infections of up-to-3-months old infants. This prospective study was carried out from April 1993 to March 1994. Detection of RSV antigen in nasopharyngeal specimens was done by enzyme immunoassay using TESTPACK RSV at our out patient clinic. During this study period, 65 young infants with respiratory tract infection visited our clinic. Seventeen patients (26%) were diagnosed as having RSV infection. Fifteen out of the 17 infants with RSV infection were observed in spring and winter. Fourteen out of the 17 infants with RSV infection had acute bronchiolitis or pneumonia. In contrast to RSV infection, only three patients out of the 48 infants with non-RSV infection had lower respiratory tract infection. In conclusion, the majority of young infants infected with RSV suffered from bronchiolitis or pneumonia.

Antigens, Viral↗

PubMed1999

An update on the pathophysiology of rhinovirus upper respiratory tract infections.

Upper respiratory tract infections are one of the most common infectious diseases in man and are characterized by relatively mild symptoms. However, complications of bacterial super-infection or asthma exacerbations are not seldomly seen. Most upper respiratory tract infections are caused by rhinoviruses. The rhinovirus is a non-enveloped 30 nm RNA-virus with over 100 serotypes that belongs to the Picornaviridae family and only replicates in primates. It is characterized by a single positive stranded genome acting not only as a template for RNA synthesis, but also encoding for a single polypeptide necessary for viral replication. The viral capsid has an icosahedral symmetry and demonstrates deep canyons, with a receptor-binding domain. Rhinoviruses are transmitted mainly via direct- or indirect contact with infected secretions and invade their host by binding to the ICAM-1 receptor on the nasal epithelium. Typical for rhinovirus upper respiratory tract infections are isolated scattered foci of infected epithelium, not showing any striking damage or cytopathic alterations, between large areas of normal epithelium. Today there is still little detailed knowledge on the pathophysiology of common cold, especially on the aspect of cellular migration and defense. A better understanding in mechanisms underlying this cellular response would not only have therapeutical consequences, but may also explain the relationship between viral infectious rhinitis and asthma or atopy. During a rhinovirus infection, a selective neutrophil and monocyte recruitment is observed. In vitro and in vivo data have demonstrated a time-limited, rhinovirus-induced increase in bradykinin, cytokine, chemokine and sICAM-1 concentrations. Epithelial derived proinflammatory cytokines initiate an adhesion cascade and activate T lymphocytes that create a TH1-type cytokine environment within the infected tissue, necessary to eradicate the virus infection. The selective recruitment of neutrophils seems linked to increased concentrations of the chemokine IL-8 and common cold symptoms. It is doubtful that the cytokine-regulated-production of specific neutralising immunoglobulins is necessary for recovery from viral illnesses and presumably only contributes to a late and temporary protection against rhinovirus reinfection. These observations confirm the crucial role that cytokines and mediators play in the pathogenesis of a rhinovirus infection by mediating chemotaxis, transmigration and activation of inflammatory- and immunocompetent cells.

Animals↗

PubMed1996

Comparison of bronchoalveolar lavage and catheter lavage to confirm ventilator-associated lower respiratory tract infection.

Lower respiratory tract infection (LRTI) is a well recognised complication of artificial ventilation in intensive care units (ICU). Ideally, specimens for microbiological analysis should be obtained during bronchoscopy, but this is not always possible. Therefore, the microbiological diagnosis of lower respiratory tract infection by broncho-alveolar lavage (BAL) obtained during bronchoscopy was compared with catheter lavage (CL) with a balloon-tipped catheter. Adult patients with clinical evidence of lower respiratory tract infection in an adult ICU were randomly assigned to undergo BAL followed by CL or vice versa. Forty ml of normal saline 0.9% were instilled and then aspirated with a flexible bronchoscope to obtain BAL. A similar volume was instilled and aspirated with a 12-gauge Foley balloon-tipped catheter to obtain a CL sample. The number of inflammatory cells, epithelial cells and organisms seen by microscopy were quantified. Culture results were semi-quantified and classified as negative, positive, equivocal or contaminated. Seventy-nine paired specimens were obtained from 66 patients, including specimens from 10 patients taken on two or more occasions. Only 20% of BAL and 16% of CL had one or more epithelial cells and bacteria were seen in 26 BAL and 21 CL specimens, respectively; 35% of BAL and CL specimens were positive and there was a discrepancy in the culture result in only two cases. Staphylococcus aureus was the pathogen isolated most frequently and polymicrobial lower respiratory infection was diagnosed on 10 occasions (15%). CL fluid is as reliable as BAL in diagnosing lower respiratory tract infection in ICU. This approach does not require bronchoscopic expertise and utilises convenient laboratory techniques.

Adolescent↗