Gene/Protein Disease Symptom Drug Enzyme Compound
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Query: UMLS:C0023241 (Legionella)
 6,990 document(s) hit in 31,850,051 MEDLINE articles (0.00 seconds)

In a prospective study of community-acquired pneumonias, 30 patients were diagnosed with Legionnaires' disease in 15 months. Clinical, laboratory and radiologic features of these patients are reviewed and compared with those who have pneumococcal pneumonia. Alcoholism, history of smoking, previous antimicrobial therapy, gastrointestinal and neurologic manifestations, elevations of serum transaminases, alkaline phosphatase and creatinine levels were more frequent in pneumonia due to Legionella pneumophila than in pneumococcal pneumonia. The presence of respiratory failure and radiologic progression were common findings that suggested L pneumophila as the etiologic agent of a community-acquired pneumonia. Development of respiratory failure was associated with involvement of several lobes and isolation of L pneumophila in any specimen. In 21 of 30 patients with Legionnaires' disease, L pneumophila was isolated from respiratory specimens. Overall mortality was 10 percent, but it increased to 27 percent in patients not treated with erythromycin initially.
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PMID:Legionella pneumophila. A cause of severe community-acquired pneumonia. 191 47

Sera obtained from 642 patients with chronic alcoholism and 400 sera from healthy donors, collected in different regions of the USSR (Moscow, the Kirghiz SSR, Transcarpathian Province, the northern Caucasus), were studied. Out of all patients with chronic alcoholism whose blood sera were examined, persons aged 20-30 years constituted 22%, 31-40 years, 41.8%, 41-50 years, 27.5%, above 50 years, 8.7%. The results of the study of the immune structure of these patients with respect to the causative agents of respiratory diseases revealed a large proportion of persons seropositive to influenza virus B Leningrad/369/75 (92-93%) and coronavirus OC-43 (78-93%). Patients with chronic alcoholism were shown to belong to a high risk group with respect to Legionella pneumophila infection. The proportion of persons with antibodies to L. pneumophila among such patients (up to 21.1%) was considerably higher than among healthy donors (not more than 6%). In different regions of the USSR large risk groups with respect to diphtheria (42-56%) and tetanus (12-45%) were detected among patients with chronic alcoholism. These patients also showed considerably higher levels of anti-tissue antibodies in comparison with the healthy population.
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PMID:[Humoral immunity indices of chronic alcoholism patients]. 356 81

Despite the fact that the epidemiology of community-acquired pneumonia and nosocomial Legionella infection is well known, there are no specific reports dealing with severe cases of Legionella pneumophila pneumonia admitted to intensive care units. We undertook a prospective study upon 84 patients with a reliable diagnosis of L. pneumophila pneumonia that required ICU admission. The study assessed the prognostic factors, clinical, radiological and outcome variables of both nosocomial (n = 33) and community-acquired (n = 51) cases of L. pneumophila pneumonia. The following variables were more common in nosocomial acquired as compared to community-acquired Legionella pneumonia: Chronic obstructive pulmonary disease (COPD) (64 versus 41%), cardiac disease (39 versus 10%), chronic renal failure (21 versus 4%), alcoholism (54 versus 18%), septic shock (33 versus 16%), and unilateral chest X-ray involvement (61 versus 39%). The crude mortality rate in this study was 30% (25 of 84) with no differences when comparing mortality between nosocomial (9, 27%) to community-acquired (16, 31%) types. The univariate analysis showed that cardiac disease, diabetes mellitus, creatinine > or = 1.8 mg/dl, septic shock, chest X-ray extension, mechanical ventilation, hyponatremia < or = 136 mEq/L, PACO2/FIO2 < 130, and blood urea levels > or = 30 mg/dl were factors related to poor outcome. On the other hand, the following two variables were related to better outcome: adequate treatment for Legionella and pneumonia improvement. The logistic regression analysis demonstrated that APACHE II score > 15 at admission (RR: 11.5; 95% CI 1.75 to 76.1; p = 0.025), and serum Na levels < or = 136 (RR: 21.3; 95% CI 1.11 to 408; p = 0.023), were the only independent factors related to death. On the other hand, improving pneumonia is associated with better outcome in Legionnaires' disease than for patients not having improving pneumonia (RR: 0.019; 95% CI: 0.036 to 0.106; p < 0.0001). A better understanding of the prognostic factors in cases of severe Legionella pneumonia will optimize our therapeutic approach in this disease and help to decrease both its mortality and morbidity rates.
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PMID:Prognostic factors of severe Legionella pneumonia requiring admission to ICU. 998 59

Severe CAP is a life-threatening condition defined by the presence of respiratory failure or symptoms of severe sepsis or septic shock. It accounts for approximately 10% of hospitalized patients with CAP. The majority of patients with severe pneumonia have underlying comorbid illnesses, with COPD, alcoholism, chronic heart disease, and diabetes mellitus being the most frequent. S. pneumoniae, Legionella spp, GNEB (especially K. pneumoniae), H. influenzae, S. aureus/spp, Mycoplasma pneumoniae, respiratory viruses (especially influenza viruses), and P. aeruginosa represent the most important causative organisms of severe CAP. Rapid initiation of appropriate antimicrobial treatment is crucial for a favorable outcome. Initial antimicrobial treatment should be based on an epidemiological (empiric) approach. Microbial investigation may be helpful in the individual case but is probably more useful to define local antimicrobial policies based on local epidemiologic and susceptibility patterns. Mortality rates range from 21% to 54%. The most important prognostic factors include general health state of the patient, appropriateness of initial antimicrobial treatment, and the existence of bacteremia, as well as factors reflecting severe respiratory failure, severe sepsis, septic hypotension or shock, and the extent of infiltrates in chest radiograph. Initial antimicrobial treatment should consist of a second (or third) generation cephalosporin and erythromycin. Modifications of this basic regimen should be considered in the presence of distinct comorbid conditions and risk factors for distinct pathogens. Promising new approaches of nonantimicrobial treatment, including noninvasive ventilation, treatment of hypoxemia, and immunomodulation, are under investigation.
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PMID:Severe community-acquired pneumonia. 1051 5

Successful microbial pathogens must be adept in obtaining growth-essential iron from healthy hosts. Some potential pathogens, however, are sufficiently impaired in iron acquisition ability so as to be dangerous mainly in hosts with such iron loading conditions as alcoholism, asplenia, hemochromatosis, beta-thalassemia major, or tobacco smoking. The association of six impaired pathogens (Capnocytophaga canimorsis, Yersinia enterocolitica and Y. pseudotuberculosis, Vibrio vulnificus, Tropheryma whippelii, and Legionella pneumophila) with iron loaded humans is described.
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PMID:Microbial pathogens with impaired ability to acquire host iron. 1083 Dec 29

In a prospective study, the etiology of community-acquired pneumonia (CAP) was investigated among consecutive patients admitted to an academic, urban public hospital in Seattle. The study population was uniquely young, was predominantly male, and had high rates of homelessness, cigarette smoking, alcoholism, injection drug use, and human immunodeficiency virus (HIV) infection. Leading causes of CAP among HIV-negative patients were aspiration, followed by Streptococcus pneumoniae, Legionella species, and Mycoplasma pneumoniae. Among HIV-positive patients, Pneumocystis carinii, Mycobacterium tuberculosis, S. pneumoniae, and M. pneumoniae were the most common etiologic agents. Severe CAP was associated with typical bacterial infections and aspiration pneumonia but not Legionella infection among HIV-negative patients and with Pseudomonas aeruginosa infections among HIV-positive patients. These findings emphasize the need to tailor empirical antibiotic therapy according to local patient populations and individual risk factors and highlight the importance of recognizing underlying HIV infection in patients who are hospitalized with CAP.
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PMID:The etiology of community-acquired pneumonia at an urban public hospital: influence of human immunodeficiency virus infection and initial severity of illness. 1144 51

An incidence of between 2 and 44 per 1000 population has been reported for community-acquired pneumonia. Epidemiologic studies describe a wide range of causative organisms, including Streptococcus pneumoniae, Haemophilus influenzae, Mycoplasma pneumoniae, Legionella spp., Moraxella catarrhalis, Chlamydia pneumoniae and viruses such as influenza A and B. However, the frequency with which they are reported varies widely. On analysis of these studies, the variation can be explained by a number of factors. The results depend on the definition of pneumonia and the criteria for assigning a causative role to any particular organism. Older studies have not included diagnostic methods for newly described organisms such as C. pneumoniae and Legionella spp. The improved diagnostic methods for these organisms and for Mycoplasma pneumoniae are reflected in more recent studies. Further variation depends on the population studied. As many patients with mild pneumonia are successfully treated in the community, those studies that are hospital-based include patients with more severe pneumonia often in the elderly or in patients with underlying diseases such as chronic obstructive pulmonary disease. The prior use of antibiotics not only contributes to the high percentage of cases for which no etiologic agent is found, but also ensures that treatment failures are selected for hospitalization. This further changes the result, depending on the antibiotic agents used most commonly in the community. The inclusion of nursing home patients or groups where alcoholism is more common will also favor particular organisms. Finally, the timing of the study may be such that an epidemic is included. This has relevance mostly for Mycoplasma pneumoniae, C. pneumoniae, Legionella spp. and influenza. In the assessment of the patient with community-acquired pneumonia, any one of the above organisms can be considered to be responsible. As initial treatment is empirical, other information can be used to ensure that an antibiotic with an adequate spectrum is chosen. Factors of importance are age, underlying illness, severity of disease and any locally recognized epidemics or endemic organisms. Differences in clinical presentation are not sufficiently distinct to allow for accurate prediction of the causative agent. Similarly, chest radiograph changes are not sufficiently specific to discriminate reliably between diverse organisms such as S. pneumoniae, Mycoplasma pneumoniae and Legionella spp. Current recommendations for choice of an empirical antibiotic agent are therefore based, not on the assumption of a single etiologic agent indicated by clinical presentation or radiographic appearances, but on age of the patient, severity of illness, the presence of underlying conditions and the range of possible organisms in that patient group.
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PMID:Community-acquired pneumonia: epidemiologic and clinical considerations. 1186 96

Community-acquired pneumonias (CAP) are still caused by Streptococcus pneumoniae, Hemophilus influenzae, or Moraxella catarrhalis. Legionella and Chlamydia pneumoniae have been defined as important atypical pathogens causing CAP. Klebsiella causes CAP primarily in patients with chronic alcoholism or in chronic care facilities. Normal hosts do not present with "unusual pathogens'' e.g., Staphylococcus aureus or Pseudomonas aeruginosa. The clinical severity of a bacterial pneumonia has important prognostic implications and predicts admission to intensive care units, duration of therapy, and complications. The factors that determine the severity of a CAP are less related to the pathogen than the underlying cardiopulmonary status of the patient as well as the patient's humoral immunity. Relatively avirulent pathogens may result in severe CAP in patients with diminished/absent splenic function or significant cardiopulmonary disease. A critical concept is to appreciate that the selection of antimicrobial therapy is not dependent on co-morbidities since the antimicrobial therapy is directed against the pathogen and not the co-morbidities. Therefore the treatment of CAP, whether moderate or severe is with the same antibiotic at the same dose. Many antibiotic regimens are equally efficacious in the treatment of CAP. The most cost effective optimal regimen covers both typical and atypical pathogens, e.g., levofloxacin, and is currently the preferred antibiotic approach to moderate or severe CAP in the CCU.
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PMID:The antibiotic treatment of severe community-acquired pneumonia admitted to the critical care unit. 1608 19

Tracing the source of a legionellosis (LG) case revealed that the Legionella pneumophila (LP) strain isolated from patient's sputum shared the same serogroup (SG) and PFGE-type with 4 LP strains obtained from a spa center. With a high LP-contamination rate (81.2%, 13/16) in all of its 16 basins, this spa center was also found to have a multi-genotypic distribution among its 13 LP isolates, which can be categorized into 5 PFGE-types. Despite such a serious contamination in the spa center, which usually had ca. 100 visitors per day, this male patient, bearing LG-risk factors of long-term heavy smoking and alcoholism, was the only case identifiable after an active investigation. To explore the possible reason for this sporadic infection, all 5 PFGE-types of LP isolated were assayed for their presence of two important virulent genes (lvh and rtx A) and were identified as either less-virulent (lvh (+) , rtx A(+)) or non-virulent (lvh (-), rtx A (-)) types. The strong virulent type (lvh (+), rtx A (+)) usually seen in clinical strains elsewhere was not found here. Moreover, the LG-causative type in this infection was the only one to be classified as the less-virulent type, with the presence of lvh gene indicating its relatively more virulent potential than other 4 PFGE-types. Accordingly, mutual interaction between LP's virulent potential and patient's health-status was suggested to be the force directing the opportunistic infection of this sporadic case. This is the first spa-associated infection caused by SG 2 of LP.
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PMID:A legionellosis case due to contaminated spa water and confirmed by genomic identification in Taiwan. 1671 44

The first point of a good diagnostic strategy for healthcare-associated pneumonia (HCAP) is correct classification of patients with specific criteria, as suggested by the last American Thoracic Society/ Infectious Diseases Society of America (ATS/IDSA) guidelines. However, clinical practice and recent literature have suggested new risk factors for multidrug-resistant infection (MRI): the presence of permanent indwelling devices, prior antibiotic use in the last 3 months, chronic and advanced pulmonary diseases (chronic obstructive pulmonary disease, bronchiectasis, etc.), history of alcoholism, and immunosuppression. The clinical presentation in HCAP patients is often unusual (mild respiratory symptoms and frequent extrapulmonary manifestations) due to different factors: advanced age, neurological disorders, and multiple chronic comorbidities. Moreover, HCAP commonly presents a worse clinical course than community-acquired pneumonia, a prolonged length of stay, and a mortality rate close to hospital-acquired pneumonia. Chest radiography and routine laboratory markers (including C-reactive protein) are always needed for clinical evaluation and severity assessment. The clinical use of new biomarkers of infection and sepsis (procalcitonin, etc.) is currently being investigated. Extensive microbiological testing to overcome the high prevalence of MRI in HCAP, including urinary antigens for Legionella and Streptococcus pneumoniae; blood cultures; Gram staining and low respiratory tract secretions (sputum, tracheobronchial aspirate, fibrobronchial aspirate, protected specimen brush, bronchoalveolar lavage); and cultures for aerobic, anaerobic, mycobacterial, and fungal pathogens are recommended, whereas the indication for serology tests for respiratory viruses and atypical pathogens is low. By contrast, the new polymerase chain reaction-based techniques for the rapid identification (2 to 4 hours) of microbial pathogens in respiratory samples (nasopharyngeal swab, bronchoalveolar lavage) seem to be the most innovative future perspective in the diagnostics of HCAP.
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PMID:Diagnostic strategies for healthcare-associated pneumonia. 1919 85


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