Aim: To evaluated the etiologic percentage of the atypical pneumoniae in outpatients and to identify the epidemiologic, clinical and radiographic features that permit to distinguish between atypical and non-atypical pneumonia. Methods: All patients underwent clinical and radiographic evaluation. Serum and sputum samples were obtained to serological tests including Legionella sp, Chlamydia sp, M. pneumoniae, Influenza A and Influenza B virus, and Gram stain, respectively. These procedures were performed on the first and 21 days after inclusion. Three independent observers reviewed chest X-rays. Results: During 22 months, 129 patients were evaluated. The final population under study comprised 69 patients (46 men - 23 women) with a mean age of 37 years. The etiologic diagnosis was defined in 34 (50%) of the patients. Etiologic agents included Chlamydia sp, 11 (16%) isolated cases; M. pneumoniae 7 (10%) cases. Influenza A was the third more frequent agent in 4 (6%) patients, and Legionella sp in 4 (6%). Mixed infections were observed with association of Chlamydia sp and M. pneumoniae in 5 (7.3%) cases, Chlamydia sp and Influenza B one (1.5%) case, and another of M. pneumoniae and Influenza A. The atypical pneumonia and non-atypical pneumonia groups were compared to respiratory symptoms and signs. There were no differences between them. The three independent observers' radiographic evaluation showed disagreement among them as to the type of pneumonia. Radiographic diagnoses of individual observers were compared to the clinical diagnoses, and no significant association was obtained for any observer. Conclusion: Pneumonia caused by "atypical" agents occurs in 50% of the outpatients with community acquired pneumonia. It is not possible to distinguish atypical pneumonia from non-atypical pneumonia. The clinical and radiographic presentations are similar in both groups.

Keywords: pneumonia; etiology; diagnosis; epidemiology

In humans, the most common types of infection are respiratory tract infections, among which viral infections predominate. Viruses can also infect the low respiratory tract, causing bronchiolitis, bronchitis and pneumonia. The objective of this review article was to show epidemiological, pathophysiological, clinical and therapeutic aspects of viral community-acquired pneumonia. These types of pneumonia are commonly caused by influenza A and B; parainfluenza 1, 2 and 3; respiratory syncytial virus; or adenovirus. We also address the types of pneumonia caused by hantaviruses, metapneumoviruses and rhinoviruses.

Keywords: Pneumonia, viral; Influenza, human; Respiratory syncytial virus infections; Hantavirus.

Organizing pneumonia, whether or not accompanied by bronchiolitis obliterans, is a specific anatomicopathological condition of the lungs that can present in a variety of clinical and radiographic ways. It can be either idiopathic or secondary to a number of diseases, including infection and drugs. Objectives: To describe the clinical manifestations, radiographic and spirometric data seen in patients with organizing pneumonia. Methods: Retrospective analysis of patients with a diagnosis of organizing pneumonia. Results: 38 patients were included in the analysis. Fourteen also had clinical conditions related to organizing pneumonia, and they presented more frequently with diffuse pulmonary infiltrates (three of four cases) and associated bronchiolitis obliterans (57% vs. 20%, p = 0,05). Of the 13 patients with bronchiolitis obliterans, only one was asymptomatic and two had localized lesions (15%). Of the eight asymptomatic patients with localized lesions, no one had associated bronchiolitis obliterans, and the radiographic appearance often resembled bronchial carcinoma. Spirometry was generally of little value to diagnosis, probably because of the high prevalence of smoking in the sample. Conclusion: The clinical and radiographic presentation of organizing pneumonia is variable. Factors that suggest the absence of coexisting bronchiolitis obliterans are the absence of symptoms and localized radiographic lesions, and this form of the disease has to be more often differentiated from bronchial carcinoma in clinical practice.

Objective: To describe the patient profile, mortality rates, the accuracy of prognostic scores, and mortality-associated factors in patients with community-acquired pneumonia (CAP) in a general hospital in Brazil. Methods: This was a cohort study involving patients with a clinical and laboratory diagnosis of CAP and requiring admission to a public hospital in the interior of Brazil between March 2014 and April 2015. We performed multivariate analysis using a Poisson regression model with robust variance to identify factors associated with in-hospital mortality. Results: We included 304 patients. Approximately 70% of the patients were classified as severely ill on the basis of the severity criteria used. The mortality rate was 15.5%, and the ICU admission rate was 29.3%. After multivariate analysis, the factors associated with in-hospital mortality were need for mechanical ventilation (OR: 3.60; 95% CI: 1.85-7.47); a Charlson Comorbidity Index score > 3 (OR: 1.30; 95% CI: 1.18-1.43); and a mental Confusion, Urea, Respiratory rate, Blood pressure, and age > 65 years (CURB-65) score > 2 (OR: 1.46; 95% CI: 1.09-1.98). The mean time from patient arrival at the emergency room to initiation of antibiotic therapy was 10 h. Conclusions: The in-hospital mortality rate of 15.5% and the need for ICU admission in almost one third of the patients reflect the major impact of CAP on patients and the health care system. Individuals with a high burden of comorbidities, a high CURB-65 score, and a need for mechanical ventilation had a worse prognosis. Measures to reduce the time to initiation of antibiotic therapy may result in better outcomes in this group of patients.

Keywords: Community-acquired infections; Pneumonia; Hospital mortality; Risk factors.

Objective: To analyze the clinical, etiological, and epidemiological aspects of community-acquired pneumonia (CAP) in hospitalized individuals. Methods: We prospectively studied 66 patients (> 14 years of age) with CAP admitted to the Hospital Estadual Sumaré, located in the Sumaré microregion of Brazil, between October of 2005 and September of 2007. We collected data related to clinical history, physical examination, pneumonia severity index (PSI) scores, and laboratory tests (blood culture; sputum smear microscopy and culture; serology for Chlamydophila pneumoniae, Mycoplasma pneumoniae, and Legionella pneumophila; and detection of Legionella sp. and Streptococcus pneumoniae antigens in urine). Results: The mean age of patients was 53 years. Most had a low level of education, and 55.7% presented with at least one comorbidity at the time of hospitalization. The proportion of elderly people vaccinated against influenza was significantly lower among the inpatients than in the general population of the Sumaré microregion (52.6% vs. > 70%). Fever was less common among the elderly patients (p < 0.05). The clinical evolution was associated with the PSI scores but not with age. The etiology was confirmed in 31 cases (50.8%) and was attributed to S. pneumoniae, principally detected by the urinary antigen test, in 21 (34.4%), followed by C. pneumoniae, in 5 (8.2%). The mortality rate was 4.9%, and 80.3% of the patients were classified as cured at discharge. Conclusions: The knowledge of the etiologic profile of CAP at the regional level favors the appropriate choice of empirical treatment, which is particularly relevant in elderly patients and in those with comorbidities. The lack of influenza vaccination in elderly patients is a risk factor for hospitalization due to CAP.

Keywords: Chlamydophila pneumoniae; Community-acquired infections; Pneumonia; Streptococcus pneumoniae; Influenza vaccines.

Objective: To analyze the temporal trends in pneumonia mortality rates (standardized by age, using the 2010 population of Brazil as the standard) in all Brazilian geographical regions between 1996 and 2012. Methods: This was an ecological time-series study examining secondary data from the Mortality Database maintained by the Information Technology Department of the Brazilian Unified Health Care System. Polynomial and joinpoint regression models, and corresponding 95% CIs, were used for trend analysis. Results: The pneumonia mortality rates in the South, Southeast, and Central-West showed a decreasing behavior until 2000, followed by increases, whereas, in the North and Northeast, they showed increasing trends virtually throughout the period studied. There was variation in annual percent change in pneumonia mortality rates in all regions except the North. The Central-West had the greatest decrease in annual percent change between 1996 and 2000, followed by an increase of the same magnitude until 2005. The 80 years and over age group was the one most influencing the trend behavior of pneumonia mortality rates in all regions. Conclusions: In general, pneumonia mortality trends reversed, with an important increase occurring in the years after 2000.

Keywords: Pneumonia/mortality; Pneumonia/epidemiology; Time series studies.

Objective: To assess the incidence of necrotizing pneumonia (NP) in children submitted to thoracoscopy, comparing patients with and without NP in terms of the presentation and clinical evolution. Methods: A retrospective study of children with pleural empyema submitted to thoracoscopy. Thoracoscopy was performed in patients not previously submitted to thoracic drainage and in whom there was evidence of loculated effusion or pneumothorax, as well as in those previously submitted to thoracic drainage and in whom there was persistent pneumothorax or fever with purulent discharge. On the basis of the thoracoscopy findings, patients were distributed into two groups: those with NP (NP group) and those without (no-NP group). Results: The study sample comprised 52 patients. Of the 24 patients with NP, 19 (79%) had undergone thoracic drainage prior to thoracoscopy, 11 (46%) presented with pneumothorax, and 16 (67%) developed bronchopleural fistula. In the NP group, the median drainage time and the median length of hospital stay were 18 and 19 days, respectively. Of the 28 patients without NP, 10 (36%) had undergone thoracic drainage prior to thoracoscopy, 9 (32%) presented pneumothorax, and 5 (18%) developed bronchopleural fistula. In the no-NP group, the median drainage time and the median length of hospital stay were 6 and 10 days, respectively. Conclusions: Pneumothorax should raise the suspicion of NP. Early thoracoscopy can be a valuable treatment option for NP in children because it hastens recovery in comparison with the medical treatment alone and avoids extensive late thoracotomy lung resections.

Keywords: Keywords: Empyema, pleural; Thoracoscopy; Pneumonia; Child.

Objective: To assess differences in the sputum microbiota of community-acquired pneumonia (CAP) patients with either COPD or asthma, specifically focusing on a patient population in Turkey. Methods: This retrospective study included hospitalized patients > 18 years of age with a diagnosis of pneumonia between January of 2021 and January of 2023. Participants were recruited from two hospitals, and three patient groups were considered: CAP patients with asthma, CAP patients with COPD, and CAP patients without COPD or asthma. Results: A total of 246 patients with CAP were included in the study, 184 (74.8%) and 62 (25.2%) being males and females, with a mean age of 66 ± 14 years. Among the participants, 52.9% had COPD, 14.2% had asthma, and 32.9% had CAP but no COPD or asthma. Upon analysis of sputum cultures, positive sputum culture growth was observed in 52.9% of patients. The most commonly isolated microorganisms were Pseudomonas aeruginosa (n = 40), Acinetobacter baumannii (n = 20), Klebsiella pneumoniae (n = 16), and Moraxella catarrhalis (n = 8). CAP patients with COPD were more likely to have a positive sputum culture (p = 0.038), a history of antibiotic use within the past three months (p = 0.03), utilization of long-term home oxygen therapy (p < 0.001), and use of noninvasive ventilation (p = 0.001) when compared with the other patient groups. Additionally, CAP patients with COPD had a higher CURB-65 score when compared with CAP patients with asthma (p = 0.004). Conclusions: This study demonstrates that CAP patients with COPD tend to have more severe presentations, while CAP patients with asthma show varied microbial profiles, underscoring the need for patient-specific management strategies in CAP.

Keywords: Community-acquired infections; Pulmonary disease, chronic obstructive; Asthma; Patient admission; Sputum; Culture techniques.

Objective: To present aspects of the evolution of lipoid pneumonia in children, based on clinical, radiological and bronchoalveolar lavage fluid findings, emphasizing the importance of bronchoalveolar lavage for the diagnosis and treatment. Methods: We included 28 children, with a mean age of 20 months (range, 1-108 months), diagnosed with chronic pneumonia refractory to antimicrobial therapy, with TB or with a combination of the two. Most of the children had at least one risk factor for aspiration, and all of them had a history of mineral oil ingestion for intestinal constipation (23/28) or complicated ascaridiasis (5/28). Clinical evaluations, tomographic evaluations and analyses of bronchoalveolar lavage fluid were carried out at the beginning of treatment and throughout a follow-up period of 24 months. Results: Tachypnea and cough were the most common symptoms. The most common radiological alterations were areas of consolidation (23/28), perihilar infiltrates (13/28) and hyperinflation (11/28). Chest CT scans showed areas of consolidation with air bronchogram (24/28), decreased attenuation in the areas of consolidation (16/28), ground-glass opacities (3/28) and crazy-paving pattern (1/28). In the analysis of the bronchoalveolar lavage fluid, Sudan staining revealed foamy macrophages, confirming the diagnosis of lipoid pneumonia. After treatment with multiple bronchoalveolar lavages (mean = 9.6), 20 children became asymptomatic, 18 of those presenting normal tomographic images. Conclusions: A diagnosis of lipoid pneumonia should be considered in patients with chronic refractory pneumonia or TB, especially if there is a history of mineral oil ingestion. Bronchoscopy with multiple bronchoalveolar lavages was an efficient treatment for the clearance of mineral oil from the lung parenchyma and the prevention of fibrosis. This strategy contributed to reducing the morbidity of lipoid pneumonia, which remains a rare diagnosis.

Keywords: Pneumonia, lipid; Bronchoalveolar lavage; Treatment outcome.

Objective: To describe the clinical features and to identify factors associated with significant severe asthma in samples of patients followed in a reference center in Salvador. Methods: A cross-sectional study of 473 adults, regularly followed in the "Asthma Control Program" in Bahia (Programa de Controle da Asma e da Rinite Alérgica na Bahia (ProAR)), reassessed systematically between 2013 and 2015. The patients were admitted for meeting previous criteria of severe asthma and were reclassified according to the most current definition proposed by a joint document of the "European Respiratory Society/American Thoracic Society" (ERS/ATS) (ERS/ATS 2014). Results: Only 88/473 (18%) were reclassified as having severe asthma by ERS/ATS criteria (SA-ERS/ATS). Among these patients, 87% were women, 48% obese, with a median Body Mass Index (BMI) of 29 kg·m2 (IQ 26-34), furthermore, 99% had symptoms of chronic rhinitis and 83% had symptoms of Gastroesophageal Reflux Disease (GERD). None of the 88 patients claimed to be current smokers. The most frequently corticosteroids were beclomethasone dipropionate (BDP) (88%) and budesonide (BUD) (69%). The majority of the evaluations reported adequate adherence (77%), however, the minority (0,6%) detected serious errors in inhalation techniques. The median Forced Expiratory Volume (FEV1) associated with post-bronchodilator test (post-BD) was 67% predicted (IQ 55-80). The median number of eosinophils in the peripheral blood was lower in patients with SA-ERS/ATS (258 cells/mm3 (IQ 116-321) than in the other patients studied [258 cells/mm3 (IQ 154-403)]. Gastroesophageal reflux symptoms were associated with a higher severity [OR = 2.2 95% CI (1.2-4.2)]. Conclusion: In this group of patients, symptoms of GERD were associated with SA-ERS/ATS and eosinophil count > 260 cells/mm3 were associated 42% with less chance SA-ERS/ATS

Keywords: Asthma; Gastroesophageal reflux disease (GERD); Eosinophils; Biomarkers.

Objective: To evaluate clinical, tomographic, and microbiological characteristics of pulmonary disease caused by M. kansasii (MKPD) in patients treated at an outpatient unit from 2006-2016. Methods: We studied thirty eight patients, and analyzed socio demographic, clinical-radiological, laboratory, and therapeutic characteristics. Results: The mean age was 64 years (SD = 10.6; IIQ = 57-72; median = 65.0), and 22 (57.9%) male patients. Pulmonary comorbidity was present in 89.5% of the patients. The most frequent comorbidity was bronchiectasis (78.9%). Previous treatment for pulmonary tuberculosis (PTB) was found in 65.9%. The most used therapeutic regimen was rifampicin, isoniazid and ethambutol (44.7%). Chest tomography (CT) showed bronchiectasis (94.1%), architectural distortion (76.5%), septum thickening (67.6%), and cavities (64.7%). Disease was bilateral in 85.2%. We observed 10.7% resistance to rifampicin, 67.9% resistance to ethambutol, and sensitivity to clarithromycin. Conclusion: In patients with structural lung disease, it is important to search for NTM, the main differential diagnosis with PTB. Chest CT showed different patterns that overlapped with structural disease caused by PTB or other lung diseases. We observed resistance to ethambutol, a drug component of the recommended regimen.

Keywords: Nontuberculous mycobacteria; Mycobacterium kansasii; Epidemiology; Treatment.

Idiopathic pulmonary fibrosis is a severe and progressive chronic fibrosing interstitial lung disease, a definitive diagnosis being established by specific combinations of clinical, radiological, and pathological findings. According to current international guidelines, HRCT plays a key role in establishing a diagnosis of usual interstitial pneumonia (UIP). Current guidelines describe three UIP patterns based on HRCT findings: a typical UIP pattern; a pattern designated "possible UIP"; and a pattern designated "inconsistent with UIP", each pattern having important diagnostic implications. A typical UIP pattern on HRCT is highly accurate for the presence of histopathological UIP, being currently considered to be diagnostic of UIP. The remaining patterns require further diagnostic investigation. Other known causes of a UIP pattern include drug-induced interstitial lung disease, chronic hypersensitivity pneumonitis, occupational diseases (e.g., asbestosis), and connective tissue diseases, all of which should be included in the clinical differential diagnosis. Given the importance of CT studies in establishing a diagnosis and the possibility of interobserver variability, the objective of this pictorial essay was to illustrate all three UIP patterns on HRCT.

Keywords: Tomography, X-ray computed; Lung diseases, interstitial; Pulmonary fibrosis.

Objective: Although ventilator-associated pneumonia (VAP) is a major cause of nosocomial infection, its role in the prognosis of patients remains undefined. The objective of this study was to evaluate the impact of VAP on the clinical evolution of patients. Methods: This was a prospective cohort study involving 233 patients on mechanical ventilation (VAP group, n = 64; control group, n = 169). Primary outcomes were time on mechanical ventilation (TMV), time in ICU (TICU), overall length of hospital stay (LHS) and in-ICU mortality. Secondary outcomes were in-hospital mortality, microbiological profile, prior use of antibiotics and risk factors for VAP acquisition. Results: Control and VAP group outcomes were, respectively, as follows: median TMV (days), 9 (interquartile range [IQR]: 5-15) and 23 (IQR: 15-37; p < 0.0001); median TICU (days), 12 (IQR: 8-21) and 27 (IQR: 17-42; p < 0.0001); median LHS (days), 33 (IQR: 18-64) and 46 (IQR: 25-90; p = 0.05); and in-ICU mortality, 38% (95% CI: 31-45) and 55% (95% CI: 42-67; p = 0.02). VAP was a predictor of in-ICU mortality (OR = 3.40; 95% CI: 1.54‑7.48). TMV (OR = 2.27; 95% CI: 1.05-4.87) and prior use of antibiotics (OR = 1.07; 95% CI: 1.04-1.10) were risk factors for VAP. VAP did not affect in-hospital mortality. Acinetobacter spp. was the most common isolate (28%). Inappropriate empirical antibiotic therapy was administered in 48% of cases. Conclusions: In this study, there was a high incidence of infection with resistant bacteria and inappropriate initial antibiotic therapy. Long TMV and prior use of antibiotics are risk factors for VAP.

Keywords: Pneumonia, ventilator-associated; Cross infection; Intensive care units; Hospital mortality; Risk factors.

Background: Idiopathic pulmonary fibrosis was recently redefined as usual interstitial pneumonia of unknown etiology. Consequently, the prognostic value of histological findings needs to be reassessed. Objective: To correlate clinical, functional and histological findings with survival in patients with idiopathic pulmonary fibrosis. Method: Patients (n = 51; mean age: 66 ± 8 years; gender: 21 females/30 males) were evaluated. Of the 51, 26 were smokers or ex-smokers. Duration of symptoms, forced vital capacity and smoking habits were recorded. All patients presented usual interstitial pneumonia verified through histology. Degree of honeycombing, established fibrosis, desquamation, cellularity, myointimal thickening of blood vessels and number of fibroblastic foci were graded according to the semiquantitative method. Results: Median duration of symptoms was 12 months and initial forced vital capacity was 72 ± 21%. Cox multivariate analysis revealed that survival correlated inversely and significantly (p < 0.05) with duration of symptoms and fibroblastic foci score, as well as with myointimal thickening of blood vessels. Limited numbers of fibroblastic foci, as well as myointimal thickening involving less than 50% of blood vessels, were predictive of greater survival. No correlation with survival was found for gender, age, forced vital capacity, inflammation or degree of cellularity. Conclusion: Semiquantitative analysis of lung biopsies yields relevant prognostic information regarding patients with usual interstitial pneumonia.

Keywords: Pulmonary fibrosis. Lung diseases, interstitial. Survival analysis.

Objective: To investigate how social and psychological characteristics differ between pregnant women who smoke and do not smoke. To explore associations between social and psychological features with changes of smoking habits by the end of pregnancy. Methods: A case-control study was set up. Smokers cases were never-smokers and ex-smokers controls. Pregnant women (n=328) from public prenatal services were interviewed. Socio-demographic data and psychological variables - personality traits, anxiety, depression, perceived stress, maternal fetal-attachment - were measured. Saliva samples were collected to measure cotinine and to check self-informed smoking status. In addition, 66 smokers were also assessed regarding smoking habits by late pregnancy. Smoking status was defined as a dependent variable. Exposure factors were analyzed through odds ratios. Logistic models and contingency tables were employed according to the nature of variables. "Qualitative change in smoking" was defined as a dependent variable for the last evaluation, and a logistic regression model was built. Results: Lower schooling, higher age, use of alcohol and drugs, living without a partner, and passive smoking showed associations with smoking. Anxiety, depression and perceived stress also exhibited positive association with smoking. Among personality traits, only Neuroticism was associated with smoking. None of the variables were associated with qualitative change in smoking by the end of pregnancy. Conclusion: Smoking during pregnancy is associated with more unfavorable social conditions. Pregnant women who smoke exhibit more negative psychological states than nonsmokers, including a profile of accentuated Neuroticism. None of the investigated variables could predict changes in smoking during pregnancy.

Keywords: Smoking; Pregnancy; Psychology; Psychosocial factors; Personality traits; Big five factor model of personality; Perceived stress; Anxiety; Depression.

Objective: To compare 28-day mortality rates and clinical outcomes in ICU patients with ventilator-associated pneumonia according to the diagnostic strategy used. Methods: This was a prospective randomized clinical trial. Of the 73 patients included in the study, 36 and 37 were randomized to undergo BAL or endotracheal aspiration (EA), respectively. Antibiotic therapy was based on guidelines and was adjusted according to the results of quantitative cultures. Results: The 28-day mortality rate was similar in the BAL and EA groups (25.0% and 37.8%, respectively; p = 0.353). There were no differences between the groups regarding the duration of mechanical ventilation, antibiotic therapy, secondary complications, VAP recurrence, or length of ICU and hospital stay. Initial antibiotic therapy was deemed appropriate in 28 (77.8%) and 30 (83.3%) of the patients in the BAL and EA groups, respectively (p = 0.551). The 28-day mortality rate was not associated with the appropriateness of initial therapy in the BAL and EA groups (appropriate therapy: 35.7% vs. 43.3%; p = 0.553; and inappropriate therapy: 62.5% vs. 50.0%; p = 1.000). Previous use of antibiotics did not affect the culture yield in the EA or BAL group (p = 0.130 and p = 0.484, respectively). Conclusions: In the context of this study, the management of VAP patients, based on the results of quantitative endotracheal aspirate cultures, led to similar clinical outcomes to those obtained with the results of quantitative BAL fluid cultures. (Brazilian Registry of Clinical Trials - ReBEC; identification number RBR-86DCDX [http://www.ensaiosclinicos.gov.br])

Keywords: Bronchoalveolar lavage fluid/diagnosis; Respiratory aspiration; Pneumonia, ventilator-associated.

Objective: To evaluate the frequency of the use of sputum examination in the clinical management of community-acquired pneumonia (CAP) in a general hospital and to determine whether its use has an impact on mortality. Methods: The medical records of CAP patients treated as inpatients between May and November of 2004 at the Nossa Senhora da Conceição Hospital, located in Porto Alegre, Brazil, were reviewed regarding the following aspects: age; gender; severity of pneumonia (Fine score); presence of sputum; sputum bacteriology; treatment history; change in treatment; and mortality. Results: A total of 274 CAP patients (134 males and 140 females) were evaluated. Using the Fine score to quantify severity, we classified 79 (28.8%) of those 274 patients as class II, 45 (16.4%) as class III, 97 (35.4%) as class IV, and 53 (19.3%) as class V. Sputum examination was carried out in 92 patients (33.6%). A valid sample was obtained in 37 cases (13.5%), and an etiological diagnosis was obtained in 26 (9.5%), resulting in a change of treatment in only 9 cases (3.3%). Overall mortality was 18.6%. Advanced age (above 65), CAP severity, and dry cough were associated with an increase in the mortality rate. Sputum examination did not alter any clinical outcome or have any influence on mortality. Conclusion: Sputum examination was used in a minority of patients and was not associated with any noticeable benefit in the clinical management of patients with CAP treated in a hospital setting.

Keywords: Pneumonia/etiology; Sputum; Diagnosis.