Background: Antimicrobial treatment of community-acquired respiratory tract infections (CARTI) is usually empiric and antibiotics are chosen on the basis of surveillance studies. The SENTRY Program was designed to monitor antimicrobial resistance via a worldwide surveillance network of sentinel laboratories. Three sites in Brazil participated in the 1997 and 1998 SENTRY Program. Methods: A total of 344 bacterial isolates, collected from patients with CARTI in 1997 and 1998, were tested against more than 20 antimicrobial agents by the broth microdilution method. Results: Among S. pneumoniae (176 isolates), 71.6% were susceptible to penicillin. High level resistance to penicillin and resistance to cefotaxime was found in 2.3 and 4.0%, respectively. The newer quinolones, levofloxacin, (MIC90 of 2 mg/mL) and gatifloxacin (MIC90 of 0.5 mg/mL) were active against 100% of the isolates tested. Among the other non-b-lactam drugs tested, the rank order of pneumococci activity was (% susceptible): chloramphenicol (97.5%) > clindamycin (94.0%) > azithromycin (90.3%) > clarithromycin (89.4%) > tetracycline (76.4%) > trimethoprim/sulfamethoxazole (60.2%). The percentage of Haemophilus influenzae (101 isolates) susceptible to amoxicillin was 90.1%, whereas among Moraxella catarrhalis (67 isolates) only 9.0% were susceptible. Clavulanic acid restored the activity of amoxicillin against both H. influenzae and M. catarrhalis. However, H. influenzae showed increased levels of resistance to trimethoprim/sulfametoxazole (55.1% susceptibility), clarithromycin (80.4% susceptibility), and cefaclor (88.2%) susceptibility). All H. influenzae and M. catarrhalis isolates were susceptible to levofloxacin (MIC90, < 0.5 mg/mL for both) and gatifloxacin (MIC90, < 0.06 mg/mL for both) with very low MICs. Conclusion: Results indicate that the rate of S. pneumoniae showing high-level penicillin resistance is still low in Brazil. However, intermediate resistance to penicillin associated with resistance to other classes of antimicrobial agents was relatively high. On the other hand, the new quinolones were highly active against 100% of the respiratory pathogens tested.

Keywords: Respiratory tract infections. Bacterial pneumonia. Microbial drug resistance. Program evaluation. Microbial sensibility tests.

Objective: To determine the prevalence, outcomes, and predictors of multidrug-resistant nosocomial lower respiratory tract infections (LRTI) in patients in an ICU. Methods: This was an observational cohort study involving patients with nosocomial LRTI (health care-associated pneumonia, hospital-acquired pneumonia, or ventilator-associated pneumonia). Data were prospectively collected between 2015 and 2019. The multidrug-resistant pathogens (MDRPs) identified in the isolates studied included resistant to extended-spectrum cephalosporin-resistant and carbapenem-resistant Acinetobacter baumannii, Klebsiella pneumoniae, and Pseudomonas aeruginosa, carbapenem-resistant Enterobacteriaceae, and methicillin-resistant Staphylococcus aureus at microbiological diagnosis. Results: During the study period, 267 patients in the ICU were diagnosed with LRTI, microbiological confirmation of LRTI having been obtained in 237. Of these, 146 (62%) had at least one MDRP isolate. Patients infected with MDRP were found to have poorer outcomes than patients infected with susceptible strains, such as prolonged mechanical ventilation (18.0 days vs. 12.0 days; p < 0.001), prolonged ICU length of stay (23.0 days vs.16.0 days; p < 0.001), and higher mortality (73% vs. 53%; p < 0.001) when compared with patients infected with susceptible strains. Hospital length of stay = 5 days (OR = 3.20; 95% CI: 1.39-7.39; p = 0.005) and prolonged use vasoactive drugs (OR = 3.15; 95% CI: 1.42-7.01; p = 0.004) were independent predictors of LRTI caused by MDRPs (LRTI-MDRP). The presence of LRTI-MDRP was found to be an independent predictor of death (OR = 2.311; 95% CI: 1.091-4.894; p = 0.028). Conclusions: Prolonged use of vasoactive drugs and prolonged hospital length of stay were independent predictors of LRTI-MDRP in this population of critically ill patients with very poor outcomes.

Keywords: Drug resistance, multiple; Healthcare-associated pneumonia; Pneumonia, ventilator-associated; Cross infection; Intensive care units.

Objective: To determine whether the concentrations of inflammatory mediators (CCL5, soluble intercellular adhesion molecule type 1 [sICAM-1], TNF-α, IL-6 and IL-10) in the nasopharyngeal secretion and in the serum of children with lower respiratory tract infection (LRTI) caused by respiratory syncytial virus (RSV) correlate with the clinical markers of disease severity. Methods: Between July of 2004 and December of 2005, 30 children less than three months of age, diagnosed with LRTI caused by RSV and admitted to a neonatal ICU, were included in this study. Results: The severity of disease at hospital admission, as determined with a modified clinical scoring system, presented a significant positive correlation with sICAM-1 and IL-10 concentrations in the nasopharyngeal secretion, as well as with IL-6 concentrations in the serum, of the patients. In addition, serum IL-6 concentrations presented a significant positive correlation with the duration of oxygen therapy and with the length of hospital stay. Conclusions: At hospital admission, the concentrations of sICAM-1 and IL-10 in the nasopharyngeal secretion, as well as the concentration of IL-6 in the serum, could be used as markers of severity in patients with LRTI caused by RSV. The serum levels of IL-6 determined at admission could also be used to predict prolonged oxygen supplementation and hospital stay.

Keywords: Respiratory syncytial virus, human; Chemokine CCL5; Intercellular adhesion molecule-1; Interleukin-6; Interleukin-10; Tumor necrosis factor-alpha.

Objective: To evaluate the incidence of viral infection in patients with acute asthma treated in the emergency room. Methods: We conducted a cohort study of patients aged 12 and older presenting to the emergency room of the Hospital de Clínicas de Porto Alegre with acute asthma. Nasopharyngeal aspirate was collected, and antigens were detected through indirect immunofluorescence staining for respiratory syncytial virus, adenovirus and influenza, as well as for parainfluenza types 1, 2, 3 and 4. Data were collected regarding demographic characteristics, medical history, the attack that led to the current emergency room visit, and clinical outcomes. Results: From March to July of 2004, 49 patients were examined for viral infection of the respiratory tract. Respiratory viruses were identified in 6 patients (3 with adenovirus, 2 with influenza A, 1 with parainfluenza type 1). The mean age of the patients with viral infection of the respiratory tract was 61.7 ± 11.5 years, compared with 41.7 ± 20.9 years for the patients without such infection (p = 0.027). There were no other significant differences in clinical characteristics or outcomes. Conclusion: The incidence of viral infection of the respiratory tract in acute asthma patients 12 years and older treated in an emergency room was 12.2%, which confirms that viral infection is a significant precipitant of acute asthma for patients in this age bracket.

Keywords: Emergency Service, Hospital; Vírus diseases/prevention & control; Asthma; Respiratory tract infections; Influenza A virus, human

Objective: The aim of this study was to detect late sequelae of foreign body aspiration in the respiratory tract of children. Methods: This study included children admitted from 1987 to 1999 to Hospital da Criança Santo Antônio, of Porto Alegre, with clinical symptoms of foreign body aspiration to the respiratory tract confirmed by chest X-ray and bronchoscopy. Thirty days after the extraction of the foreign body a perfusion lung scan with technetium was performed. Results: 77% of the foreign bodies were organic materials. In 65% of children the aspiration event occurred at least 7 days before referral. The main location of foreign body was in the right lower lobe bronchus. Perfusion lung scans were performed in 24 patients. In 67% of them reduction in lung perfusion was detected. A chance of sequelae was 3.8 times greater in those patients who had the foreign body removed after 7 days from the aspiration event. Conclusion: This study showed that children that have had foreign body aspiration may have perfusion sequelae in their lungs even after removal of the foreign body. These sequelae were more frequent if the removal was delayed in 7 days of aspiration. Pediatricians must keep this in mind at the follow-up of children that have had foreign body aspiration.

Keywords: foreign bodies; aspiration; bronchi; prognosis

Objective: To create a mechanical model that could be regulated to simulate the conditioning of inspired and expired air with the same normal values of temperature, pressure, and relative humidity as those of the respiratory system of a healthy young man on mechanical ventilation. Methods: Using several types of materials, a mechanical device was built and regulated using normal values of vital capacity, tidal volume, maximal inspiratory pressure, positive end-expiratory pressure, and gas temperature in the system. The device was submitted to mechanical ventilation for a period of 29.8 min. The changes in the temperature of the air circulating in the system were recorded every two seconds. Results: The statistical analysis of the data collected revealed that the device was approximately as efficient in the conditioning of air as is the respiratory system of a human being. Conclusion: By the study endpoint, we had developed a mechanical device capable of simulating the conditioning of air in the respiratory tract. The device mimics the conditions of temperature, pressure, and relative humidity seen in the respiratory system of healthy individuals.

Keywords: Thermodynamics; Respiration, artificial; Temperature.

Objective: To evaluate the resistance values obtained through the use of the forced oscillation technique in patients with varying degrees of airway obstruction resulting from silicosis. Methods: A total of 40 never-smoking volunteers were analyzed: 10 were healthy subjects with no history of pulmonary disease or silica exposure, and 30 had silicosis. The forced oscillation technique was used to examine the subjects, and spirometry was used as a reference in order to classify the obstruction by degree. This classification resulted in five groups: control (n = 10); normal exam, composed of individuals diagnosed clinically and radiologically with silicosis but presenting normal spirometry results (n = 7); mild obstruction (n = 10); moderate obstruction (n = 8); and severe obstruction (n = 5). Results: The reduction observed in the spirometric values corresponded to a significant increase in the total respiratory resistance (p < 0.001), as well as in airway resistance (p < 0.003). A significant reduction in ventilation homogeneity was also observed (p < 0.004). Conclusion: In individuals with silicosis, the additional respiratory resistance-related data obtained through the use of the forced oscillation technique can complement spirometric data. Therefore, the forced oscillation technique presents great potential for the analysis of such patients.

Keywords: Pneumoconiosis; Silicosis; Forced expiratory volume; Oscillometry; Respiratory function tests

We compared the nitrate reductase assay with the proportion method, which is considered the gold standard, in 57 Mycobacterium tuberculosis strains isolated from patients treated at the Federal University of Minas Gerais Hospital das Clínicas, located in the city of Belo Horizonte, Brazil. For rifampin and isoniazid, the sensitivity, specificity, and accuracy of the nitrate reductase assay were all 100%, whereas they were 100%, 88.9%, and 66.7%, respectively, for streptomycin and 98.0%, 100%, and 98.2%, respectively, for ethambutol. The mean time to results was ten days. In the study sample, the nitrate reductase assay proved highly accurate and showed excellent concordance with the gold standard.

Keywords: Mycobacterium tuberculosis; Microbial sensitivity tests; Tuberculosis, multidrug-resistant; Nitrate reductase.

Objective: To describe and analyze clinical symptoms and spirometric alterations of patients with chronic obstructive pulmonary disease (COPD) and history of exposure to wood and tobacco smoke. Methods: We retrospectively evaluated data related to 170 patients distributed into 3 groups: 34 exposed only to wood smoke, 59 patients exposed only to tobacco smoke and 77 patients exposed to both. Results: The groups did not differ significantly in terms of age (p = 0.225) or degree of exposure, considering each type of exposure in isolation or in combination (p = 0.164 and p = 0.220, respectively). Females predominated in the group exposed to wood smoke. There were no differences among the groups regarding respiratory symptoms (p > 0.05), and moderate dyspnea predominated in the three groups (p = 0.141). The group exposed to wood smoke presented higher percentages of forced expiratory volume in one second/forced vital capacity ratio and of forced expiratory volume in one second (p < 0.05). Positive results on bronchodilator testing occurred more frequently in the group exposed to tobacco smoke. The percentage of severe and extremely severe obstruction was significantly higher in the group exposed to tobacco smoke (44.1%) than in that exposed to wood smoke (11.8%; p = 0.006). Conclusions: Respiratory symptoms and pulmonary function alterations consistent with COPD were observed in the groups of patients exposed to wood smoke. However, those alterations were not as significant as the alterations observed in the groups exposed to tobacco smoke. This study emphasizes the importance of prospective studies in evaluating the risk of wood-smoke-related COPD in Brazil, as well as the need for preventive measures in this area.

Keywords: Pulmonary disease, chronic obstructive; Smoking; Air pollution, indoor; Smoke.

Background: Empyema is a serious disease classically characterized by purulence within the pleural cavity. Early diagnosis demands immediate treatment, although there is still great controversy surrounding the question of what is the best therapy. Objective: To analyze the method of using thoracentesis and pleural irrigation, combined with the intrapleural application of an antimicrobial agent, to treat empyema - and to compare this method with others described in the literature. Method: Between January 1999 and May 2000, 17 patients diagnosed with loculated or diffuse pleural empyema were submitted to thoracentesis, followed by thorough washing of the pleural cavity with isotonic solution and intrapleural administration of a non-irritating antimicrobial agent to the pleura. Results: The group of patients studied consisted of 15 men and 2 women, and the average age was 44. The most common clinical symptoms were fever, productive cough, chest pain and dyspnea, and the most common cause was pneumonia. Macroscopically, 12 patients presented obviously purulent pleural fluid. In 4 (26.67%) of the patients, the etiological agent was identified, the most frequent being Staphylococcus sp. Pulmonary decortication was indicated in 2 cases, and those 2 patients were therefore excluded. The average length of hospitalization was 17.1 days, although 3 patients received the treatment as outpatients. No recurrence or mortality was observed with the use of this methodology. Conclusion: This approach reduced the need for invasive procedures, proving to be safe and efficient, with lower rates of morbidity and mortality than other modalities of treatment.

Keywords: Empyema/Pleural, Pleura/Blood Supply, Treatment Outcome, Treatment Effectiveness.

The correlation between resistance to pyrazinamide (PZA) and resistance to other first-line antituberculosis drugs was investigated in 395 Mycobacterium tuberculosis strains isolated from clinical specimens, representing 14% of the overall number of M. tuberculosis isolates obtained between 2003 and 2008 at the laboratory of a referral university hospital for tuberculosis. A high correlation was found between resistance to PZA and multidrug resistance, as well as between PZA resistance and resistance to rifampin, isoniazid, and ethambutol (p < 0.01 for all). These results highlight the importance of performing PZA susceptibility testing prior to the prescription of this drug in order to treat drug-resistant and multidrug-resistant tuberculosis.

Keywords: Tuberculosis/drug therapy; Tuberculosis/microbiology; Antibiotics, antitubercular.

Objective: To determine the spatial distribution of tuberculosis in the city of Ribeirão Preto, located in the state of São Paulo, Brazil, between 1998 and 2002, with a focus on the potential spatially-dependent nature of its occurrence. Methods: The secondary Epi-Tb database of the Ribeirão Preto Municipal Secretary of Health. Georeferencing of tuberculosis cases was performed using MapInfo 6.5 software, and the Spring program was used for statistical analysis of spatial data. Results: Through analysis of the existing spatial pattern and those of the previous years analyzed, we found a consistent pattern of spatial distribution of tuberculosis in Ribeirão Preto. Although there are areas that were homogeneous in terms of risk, the highest concentrations of cases were found in one zone, consisting of middle- to lower middle-class neighborhoods, located in the northeast part of the city. Conclusion: These results add to the store of knowledge regarding the spatial distribution of tuberculosis in Ribeirão Preto in various periods, emphasizing the importance of space as a methodological alternative to aid the planning, monitoring and evaluation of health care programs, allowing interventions to be more appropriately directed in order to decrease inequalities in the allocation of health care resources.

Keywords: Tuberculosis/epidemiology; Health status indicators; Residence characteristics; Urban health/ statistics & numerical data; Topography, medical

Objective: To compare children/adolescents with mild or moderate asthma and healthy subjects in terms of respiratory muscle strength, correlating it with spirometric variables in the former group. Methods: This was a cross-sectional study involving individuals 6-16 years of age and clinically diagnosed with mild/moderate asthma, together with a group of healthy, age- and gender-matched subjects. We determined spirometric values, as well as MIP and MEP, and we selected three reproducible measurements (variation < 10%). Results: We evaluated 75 patients with asthma and 90 controls. The mean age was 10.0 ± 2.6 years. There were no statistically significant differences between the controls and the asthma group regarding MIP (−89.7 ± 26.7 cmH2O vs. −92.2 ± 26.3 cmH2O; p = 0.541) or MEP (79.2 ± 22.9 cmH2O vs. 86.4 ± 24.0 cmH2O; p = 0.256). The groups were subdivided by age (children and adolescents: 6-12 and 13-16 years of age, respectively). Within the asthma group, there was a significant difference between the child and adolescent subgroups in terms of MEP (74.1 ± 24.1 cmH2O vs. 92.1 ± 21.9 cmH2O; p < 0.001) but not MIP (p = 0.285). Within the control group, there were significant differences between the child and adolescent subgroups in terms of MIP (−79.1 ± 17.7 cmH2O vs. −100.9 ± 28.1 cmH2O; p < 0.001) and MEP (73.9 ± 18.7 cmH2O vs. 90.9 ± 28.1cmH2O; p < 0.001). In the asthma group, spirometric variables did not correlate with MIP or MEP. Conclusions: In our sample, asthma was found to have no significant effect on respiratory muscle strength.

Objective: To evaluate whether respiratory therapy followed by the use of inhaled albuterol modifies the pulmonary deposition of inhaled tobramycin in patients with cystic fibrosis (CF) and whether pulmonary deposition correlates with disease severity or genotype. Methods: A prospective study was carried out including patients with CF older than 6 years of age and colonized with Pseudomonas aeruginosa. Exclusion criteria were pulmonary exacerbation, changes in therapy between the study phases and FEV1 < 25%. All patients were submitted to pulmonary scintigraphy by means of a scintillation camera equipped with a low-energy all-purpose collimator in order to evaluate drug penetration following the administration of inhaled 99mTc-tobramycin, as well as to pulmonary perfusion with 99mTc-macroaggregated albumin (phase 1). One month later, the same procedure was performed following respiratory therapy and administration of inhaled albuterol (phase 2). Results: We included 24 patients (12 males) aged 5-27 years (mean ± SD: 12.85 ± 6.64 years). The Shwachman score (SS) was excellent/good in 8 patients, moderate/fair in 16 and poor in 0. Genotyping revealed that 7 patients were ΔF508 homozygotes, 13 were ΔF508 heterozygotes; and 4 presented other mutations. In all patients, lung deposition of tobramycin decreased in phase 2, especially in those with moderate/fair SS (p = 0.017) and in heterozygotes (p = 0.043). Conclusions: The use of a respiratory therapy technique and the administration of inhaled albuterol immediately prior to the use of inhaled tobramycin decreased the pulmonary deposition of the latter in CF patients, and this reduction correlates with disease severity and genotype.

Keywords: Cystic fibrosis; Tobramycin; Respiratory therapy; Albuterol; Radionuclide imaging.

Smoking is the leading cause of respiratory disease (RD). The harmful effects of smoking on the respiratory system begin in utero and influence immune responses throughout childhood and adult life. In comparison with "healthy" smokers, smokers with RD have peculiarities that can impede smoking cessation, such as a higher level of nicotine dependence; nicotine withdrawal; higher levels of exhaled carbon monoxide; low motivation and low self-efficacy; greater concern about weight gain; and a high prevalence of anxiety and depression. In addition, they require more intensive, prolonged treatment. It is always necessary to educate such individuals about the fact that quitting smoking is the only measure that will reduce the progression of RD and improve their quality of life, regardless of the duration and severity of the disease. Physicians should always offer smoking cessation treatment. Outpatient or inpatient smoking cessation treatment should be multidisciplinary, based on behavioral interventions and pharmacotherapy. It will thus be more effective and cost-effective, doubling the chances of success.

Keywords: Respiratory tract diseases/therapy; Respiratory tract diseases/drug therapy; Tobacco use disorder/epidemiology; Smoking cessation; Counseling; Lung neoplasms.

Objective: Respiratory syncytial virus (RSV) is a major cause of severe respiratory infections in older adults, particularly those with comorbidities. Despite its clinical impact, RSV remains underdiagnosed and underreported. We sought to assess the burden of RSV in older adults (= 60 years of age) in Brazil using national surveillance data for the 2022-2023 period. Methods: We analyzed RSV cases reported in the Sistema de Informação de Vigilância Epidemiológica, identifying them among reported cases of SARS. Cases were examined by demographic characteristics, seasonal trends, and clinical outcomes. RSV cases were compared across defined etiologies. Results: Among 355,230 reported cases of SARS in older adults, 201,965 (56.8%) had a defined etiology, and 1,465 (0.7%) were confirmed as RSV cases. Cases peaked in the second quarter of each year, with the highest incidence in the southern and southeastern regions. Despite a low hospitalization rate (2.3 per 100,000 population), severe outcomes were common: 30.4% required ICU admission, and 24.9% resulted in death, with mortality being highest in those = 90 years of age. Conclusions: RSV-related hospitalizations in Brazil appear underestimated, with reported cases likely representing the most severe spectrum due to underreporting and diagnostic limitations. Seasonal patterns peaked in April-May, and regional differences highlight a higher incidence in the southern and southeastern regions, likely due to epidemiological factors and diagnostic disparities. Although the recent approval of RSV vaccines offers an opportunity to reduce disease burden, successful implementation requires broader access and inclusion in the Brazilian National Immunization Program. Strengthening surveillance, diagnostic capacity, and reporting processes is critical for better disease assessment and public health planning.

Keywords: Respiratory syncytial virus infections; Severe acute respiratory syndrome; Hospitalization; Epidemiology; Aged; Surveillance.

Objective: To report data regarding COPD patients admitted to the ICU of a referral hospital for respiratory diseases, including outcomes and treatment evaluation. Methods: Study of a series of patients with respiratory failure and COPD admitted to the ICU of Nereu Ramos Hospital, located in the city of Florianópolis, Brazil, between October of 2006 and October of 2007. Data related to demographics, causes of hospitalization, pharmacological treatment, ventilatory support, length of hospital stay, in-hospital complications, ICU mortality, and 28-day mortality were obtained from the medical charts of the patients. Acute Physiology and Chronic Health Evaluation II (APACHE II) scores were calculated. Mortality at 18 months was assessed by subsequent telephone calls. Results: During the study period, 192 patients were admitted to the ICU, 24 (12.5%) of whom were diagnosed with respiratory failure and COPD. The mean length of ICU stay was 12.0 ± 11.1 days. Noninvasive ventilation was used in 10 of the 24 patients (41.66%) and failed in 5 of those 10. Invasive mechanical ventilation (IMV) was used in a total of 15 patients (62.5%). Overall ICU mortality and 28-day mortality were 20.83% and 33.33%, respectively. However, 18-month mortality was 62.5%. Conclusions: Respiratory failure associated with COPD was responsible for 12.5% of the ICU admissions. Orotracheal intubation and IMV were necessary in 62.5% of the cases. The ICU mortality rate was in accordance with that predicted by the APACHE II scores. However, late mortality was high.

Keywords: Epidemiology; Respiration, artificial; Respiratory insufficiency; Pulmonary disease, chronic obstructive; Intensive care units; Mortality.

Objective: The objective of this study was to evaluate the applicability of a modified version of the Saint George's Respiratory Questionnaire. The version evaluated elicits "agree" and "do not agree", rather than "yes" and "no", responses. The intention is to facilitate the comprehension of double-negative questions and to promote better recollection of symptoms by patients by shortening their symptom histories from 12 months to 3 months. Methods: A total of 30 clinically stable patients with chronic obstructive pulmonary disease were evaluated. The Saint George's Respiratory Questionnaire and the modified version of the same were administered 15 days apart. Results: All of the patients presented health-related alterations in their quality of life. Comparing mean scores between the two questionnaires, the greatest difference was seen in the Symptoms domain. No significant differences were found in any of the remaining domains or in the total scores. In a subsequent analysis, significant correlations between the two questionnaires were found in all domains: Symptoms (r = 0.71; p < 0.001); Activity (r = 0.75; p < 0.001); Impact (r = 0.73; p < 0.001) and Total (r = 0.86; p < 0.001). Conclusion: The modified version of the Saint George's Respiratory Questionnaire is as effective as the original in gauging quality of life. However, various symptoms recollection time frames should be investigated in order to determine which would be the best time frame to employ in the analysis.

Keywords: Pulmonary disease, chronic obstructive; Quality of life; Reproducibility of results; Cross-cultural comparison; Questionnaires