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Current Opinion in Infectious Diseases Apr 2010Legionella pneumophila is increasingly recognized as a significant cause of sporadic and epidemic community-acquired and nosocomial-acquired pneumonia. This review... (Review)
Review
PURPOSE OF REVIEW
Legionella pneumophila is increasingly recognized as a significant cause of sporadic and epidemic community-acquired and nosocomial-acquired pneumonia. This review focuses on the latest literature concerning the epidemiology, pathogenesis, clinical presentation, diagnosis, and treatment of Legionnaires' disease.
RECENT FINDINGS
A significant increase in the incidence of Legionnaires' disease in the United States has been documented over the last years. L. pneumophila has recently been found to be a leading cause of community-acquired pneumonia in hospitalized and ambulatory patients in Germany. Recent studies provide insight into the understanding of the pathogenesis of Legionnaires' disease and the relevance of the formation of biofilms. Clinical manifestations of Legionnaires' disease are not specific and current diagnostic scores are of limited use. Several recent studies offer useful information concerning Legionnaires' disease in immunosuppressed patients. A systematic review of English literature performed to assess test characteristics of Legionella urinary antigen has found that the pooled sensitivity of the test was 0.74 and specificity was 0.991. Improved clinical response has been observed for patients with Legionnaires' disease treated with highly active antimicrobial agents against Legionella.
SUMMARY
Legionnaires' disease is a significant health problem in many countries. Clinical manifestations are unreliable in diagnosing Legionnaires' disease. Therefore, diagnostic laboratory tests for Legionella, including the urinary antigen test, should be applied to all patients with pneumonia. Levofloxacin (or other fluoroquinolone) or azithromycin are the current drugs of choice for treatment of Legionnaires' disease. Effective preventive strategies are needed.
Topics: Anti-Bacterial Agents; Antigens, Bacterial; Azithromycin; Community-Acquired Infections; Cross Infection; Germany; Humans; Incidence; Legionella pneumophila; Legionnaires' Disease; Levofloxacin; Ofloxacin; United States
PubMed: 20051846
DOI: 10.1097/QCO.0b013e328336835b -
Environmental Research Nov 2022A number of studies suggest that meteorological conditions are related to the risk of Legionnaires' disease (LD) but the findings are not consistent. A systematic review...
A number of studies suggest that meteorological conditions are related to the risk of Legionnaires' disease (LD) but the findings are not consistent. A systematic review was conducted to investigate the association of weather with sporadic LD and highlight the key meteorological conditions related to this outcome. PubMed, EMBASE, The Cochrane Library and OpenGrey were searched on 26-27 March 2020 without date, language or location restrictions. Key words included "legionellosis", "legionnaires' disease", combined with "meteorological conditions", "weather", "temperature", "humidity", "rain", "ultraviolet rays", "wind speed", etc. Studies were excluded if they did not examine the exposure of interest, the outcome of interest and their association or if they only reported LD outbreak cases. The study was conducted according to the Preferred Reporting Items for Systematic Reviews and Meta-Analyses (PRISMA) guidelines and it was registered in PROSPERO (#CRD42020168869). There were 811 articles, of which 17 were included in the review. The studies investigated different meteorological variables and most of them examined the combined effect of several variables. The most commonly examined factors were precipitation and temperature, followed by relative humidity. The studies suggested that increased precipitation, temperature and relative humidity were positively associated with the incidence of LD. There was limited evidence that higher wind speed, pressure, visibility, UV radiation and longer sunshine duration were inversely linked with the occurrence of LD. A period of increased but not very high temperatures, followed by a period of increased precipitation, favour the occurrence of LD. Increased awareness of the association of temperature and precipitation and LD occurrence among clinicians and public health professionals can improve differential diagnosis for cases of sporadic community-acquired pneumonia and at the same time contribute to improving LD surveillance.
Topics: Humans; Humidity; Legionnaires' Disease; Meteorology; Temperature; Weather
PubMed: 35964674
DOI: 10.1016/j.envres.2022.114080 -
Microorganisms Feb 2022Legionnaires' Disease (LD) is a severe, sometimes fatal interstitial pneumonia due to . Since the inception of the SARS-CoV-2 pandemic, some contradictory reports about... (Review)
Review
Legionnaires' Disease (LD) is a severe, sometimes fatal interstitial pneumonia due to . Since the inception of the SARS-CoV-2 pandemic, some contradictory reports about the effects of lockdown measures on its epidemiology have been published, but no summary evidence has been collected to date. Therefore, we searched two different databases (PubMed and EMBASE) focusing on studies that reported the occurrence of LD among SARS-CoV-2 cases. Data were extracted using a standardized assessment form, and the results of such analyses were systematically reported, summarized, and compared. We identified a total of 38 articles, including 27 observational studies (either prospective or retrospective ones), 10 case reports, and 1 case series. Overall, data on 10,936 SARS-CoV-2 cases were included in the analyses. Of them, 5035 (46.0%) were tested for either through urinary antigen test or PCR, with 18 positive cases (0.4%). A pooled prevalence of 0.288% (95% Confidence Interval (95% CI) 0.129-0.641), was eventually calculated. Moreover, detailed data on 19 co-infections LD + SARS-CoV-2 were obtained (males: 84.2%; mean age: 61.9 years, range 35 to 83; 78.9% with 1 or more underlying comorbidities), including 16 (84.2%) admissions to the ICU, with a Case Fatality Ratio of 26.3%. In summary, our analyses suggest that the occurrence of SARS-CoV-2- infections may represent a relatively rare but not irrelevant event, and incident cases are characterized by a dismal prognosis.
PubMed: 35336074
DOI: 10.3390/microorganisms10030499 -
Chest Dec 2009Urinary antigen assays offer simplicity and rapidity in diagnosing Legionnaires' disease, though studies report a range of sensitivities. We conducted a systematic... (Meta-Analysis)
Meta-Analysis Review
BACKGROUND
Urinary antigen assays offer simplicity and rapidity in diagnosing Legionnaires' disease, though studies report a range of sensitivities. We conducted a systematic review to assess the test characteristics of Legionella urinary antigen.
METHODS
We searched Medline, Excerpta Medica Database, and bibliographies of retrieved articles. English-language studies were used and included if the absolute number of true-positive, false-negative, true-negative, and false-positive observations were available, and the "gold standards" were described clearly. Two investigators independently reviewed articles and extracted data. Quality was assessed with the Quality Assessment for Diagnostic Accuracy Studies (QUADAS). Sensitivities and specificities were pooled using a random-effects model weighted with the inverse of the SE calculated through the Wald method.
RESULTS
Fifty articles were retrieved for detailed evaluation, and 30 met the inclusion criteria. All but two studies focused on serotype 1 Legionella. Forty assays were reported using six different methodologies, whereas 26 assays used commercial tests, and 14 assays used in-house tests. Study quality was generally low, with average QUADAS scores of 4.4 of a total of 14 points (range, 1 to 9 points). The pooled sensitivity was 0.74 (95% CI, 0.68 to 0.81), and the specificity was 0.991 (95% CI, 0.984 to 0.997). Higher quality studies had lower sensitivity, and there was evidence of publication bias.
CONCLUSIONS
Legionella urinary antigen for serotype 1 appears to have excellent specificity, though modest sensitivity. However, the poor quality of the included studies and the presence of publication bias suggest an overestimation of test performance. High-quality studies are needed.
Topics: Antigens, Bacterial; Humans; Legionella; Legionellosis; Sensitivity and Specificity; Urinalysis
PubMed: 19318671
DOI: 10.1378/chest.08-2602 -
Journal of Travel Medicine 2015Travel-associated Legionnaires' disease (LD) is a serious problem, and hundreds of cases are reported every year among travelers who stayed at hotels, despite the... (Review)
Review
BACKGROUND
Travel-associated Legionnaires' disease (LD) is a serious problem, and hundreds of cases are reported every year among travelers who stayed at hotels, despite the efforts of international and governmental authorities and hotel operators to prevent additional cases.
METHODS
A systematic review of travel-associated LD events (cases, clusters, outbreaks) and of environmental studies of Legionella contamination in accommodation sites was conducted. Two databases were searched (PubMed and EMBASE). Data were extracted from 50 peer-reviewed articles that provided microbiological and epidemiological evidence for linking the accommodation sites with LD. The strength of evidence was classified as strong, possible, and probable.
RESULTS
Three of the 21 hotel-associated events identified and four of nine ship-associated events occurred repeatedly on the same site. Of 197 hotel-associated cases, 158 (80.2%) were linked to hotel cooling towers and/or potable water systems. Ship-associated cases were most commonly linked to hot tubs (59/83, 71.1%). Common contributing factors included inadequate disinfection, maintenance, and monitoring; water stagnation; poor temperature control; and poor ventilation. Across all 30 events, Legionella concentrations in suspected water sources were >10,000 cfu/L, <10,000 cfu/L, and unknown in 11, 3, and 13 events, respectively. In five events, Legionella was not detected only after repeated disinfections. In environmental studies, Legionella was detected in 81.1% of ferries (23/28) and 48.9% of hotels (587/1,200), while all 12 cruise ships examined were negative.
CONCLUSIONS
This review highlights the need for LD awareness strategies targeting operators of accommodation sites. Increased standardization of LD investigation and reporting, and more rigorous follow-up of LD events, would help generate stronger, more comparable evidence on LD sources, contributing factors, and control measure effectiveness.
Topics: Disease Outbreaks; Humans; Legionella pneumophila; Legionnaires' Disease; Risk Factors; Ships; Travel
PubMed: 26220258
DOI: 10.1111/jtm.12225 -
Journal of Medical Microbiology Apr 2017Rapid and effective diagnosis of Legionnaires' disease (LD) cases is extremely important so that timely and appropriate therapy can be provided, thereby lowering the... (Review)
Review
PURPOSE
Rapid and effective diagnosis of Legionnaires' disease (LD) cases is extremely important so that timely and appropriate therapy can be provided, thereby lowering the morbidity and mortality rates and reducing the health and economic costs associated with this disease.
METHODOLOGY
Diagnosis is established solely by microbiological tests. There are several methods available, each with different performance, sensitivity and specificity characteristics, and further understanding is required. Our objective was to assess the accuracy of urinary antigen detection, direct fluorescent antibody (DFA) staining, serological testing and the polymerase chain reaction (PCR) method versus culture analysis (the reference standard) in patients suspected of being infected with Legionella or patients with laboratory-confirmed LD. We performed a MEDLINE search in November 2014. Two authors independently assessed the trials and extracted data. Pooled analysis was performed through Meta-DiSc version 1.4.
RESULT
The inclusion criteria were met by 11 studies. All the studies evaluated PCR and DFA tests to detect Legionella in clinical specimens, comparing them to culture techniques, and were included in the meta-analysis. The pooled sensitivity and specificity for PCR were 83 % [95 % confidence interval (CI): 79-87 %] and 90 % (95 % CI: 88-92 %), respectively. DFA was evaluated in one study and the sensitivity and specificity of this test were 67 % (95 % CI: 30-93 %) and 100 % (95 % CI: 91-100 %), respectively. PCR had high sensitivity and specificity for early diagnosis of LD.
CONCLUSION
Culture analysis is deemed necessary for epidemiological studies, molecular strain typing and antibiotic sensibility evaluations; however, the performance of PCR in recent studies calls for additional, well-designed studies in order to achieve the best standard test, which will enable optimization of the Legionella infection diagnostic.
Topics: Antigens, Bacterial; Diagnostic Tests, Routine; Fluorescent Antibody Technique, Direct; Humans; Legionnaires' Disease; Polymerase Chain Reaction; Sensitivity and Specificity
PubMed: 28463665
DOI: 10.1099/jmm.0.000454 -
International Journal of Environmental... Feb 2022Legionnaires' disease (LD) () is a common cause of community-acquired pneumonia (CAP) in those requiring hospitalization. Geographical variation in the importance of... (Meta-Analysis)
Meta-Analysis Review
Legionnaires' disease (LD) () is a common cause of community-acquired pneumonia (CAP) in those requiring hospitalization. Geographical variation in the importance of species as an aetiologic agent of CAP is poorly understood. We performed a systematic review and meta-analysis of population-based observational studies that reported the proportion of infection in patients with CAP (1 January 1990 to 31 May 2020). Using five electronic databases, articles were identified, appraised and reported in accordance with the Preferred Reporting Items for Systematic Reviews and Meta-Analysis (PRISMA) guidelines. The quality of the included studies was assessed using the Newcastle-Ottawa Scale. Univariate and multivariate meta-regression analyses were conducted using study design, WHO region, study quality and healthcare setting as the explanatory variables. We reviewed 2778 studies, of which 219 were included in the meta-analysis. The mean incidence of CAP was 46.7/100,000 population (95% CI: 46.6-46.8). The mean proportion of as the causative agent for CAP was 4.6% (95% CI: 4.4 to 4.7). Consequently, the mean incidence rate was 2.8/100,000 population (95% CI: 2.7-2.9). There was significant heterogeneity across all studies = 99.27% ( < 0.0001). After outliers were removed, there was a decrease in the heterogeneity ( = 43.53%). contribution to CAP has a global distribution. Although the rates appear highest in high income countries in temperate regions, there are insufficient studies from low- and middle-income countries to draw conclusions about the rates in these regions. Nevertheless, this study provides an estimate of the mean incidence of infection in CAP, which could be used to estimate the regional and global burden of LD to support efforts to reduce the impact of this infection as well as to fill important knowledge gaps.
Topics: Community-Acquired Infections; Humans; Legionella; Legionella pneumophila; Legionellosis; Legionnaires' Disease; Pneumonia
PubMed: 35162928
DOI: 10.3390/ijerph19031907 -
European Journal of Internal Medicine Feb 2024The optimal antimicrobial regimen for adults with respiratory failure due to Legionella pneumonia remains controversial. A systematic review was performed to assess the...
The optimal antimicrobial regimen for adults with respiratory failure due to Legionella pneumonia remains controversial. A systematic review was performed to assess the impact on outcomes comparing quinolones versus macrolides. A literature search was conducted in PubMed, Cochrane Library and Web of Science between 2012 and 2022. It yielded 124 potentially articles and ten observational studies met the inclusion criteria. A total of 4271 patients were included, 2879 (67 %) were male. A total of 1797 (42 %) subjects required intensive care unit (ICU) admission and 942 (52 %) mechanical ventilation. Fluoroquinolones and macrolides alone were administered in 1397 (33 %) and 1500 (35 %) subjects, respectively; combined therapy in 204 (4.8 %) patients. Overall mortality was 7.4 % (319 patients), with no difference between antibiotics. When data from the three studies with severe pneumonia were pooled together, mortality with fluoroquinolones alone was statistically superior to macrolides alone (72.8 % vs 30.8 %, p value 0.027). Hospital length of stay and complications were comparable. Our findings suggest that macrolides and quinolones were comparable for hospitalized Legionella pneumonia. However, in severe pneumonia, a randomized clinical trial is an unmet clinical need. PROSPERO registration number: CRD42023389308.
Topics: Adult; Humans; Male; Female; Macrolides; Quinolones; Anti-Bacterial Agents; Legionnaires' Disease; Fluoroquinolones; Legionella; Respiratory Insufficiency; Randomized Controlled Trials as Topic
PubMed: 37730517
DOI: 10.1016/j.ejim.2023.09.013 -
The Journal of Antimicrobial... Sep 2014Legionellosis is a life-threatening disease. The clinical superiority of quinolones or macrolides for treating patients with legionellosis has not been established. (Comparative Study)
Comparative Study Meta-Analysis Review
BACKGROUND
Legionellosis is a life-threatening disease. The clinical superiority of quinolones or macrolides for treating patients with legionellosis has not been established.
METHODS
We performed a systematic review and meta-analysis of studies reporting data that allowed the comparison of quinolones versus macrolides in the treatment of proven legionellosis published from 1 January 1985 to 31 January 2013. We collected baseline aggregate patient characteristics. Studied outcomes included mortality, clinical cure, time to apyrexia, length of hospital stay and occurrence of complications in each treatment group. Treatment effect was assessed using a Mantel-Haenszel random effects model.
RESULTS
Among 1005 abstracts reviewed, 12 studies were selected (n=879 patients). No randomized controlled trial was performed directly comparing quinolone and macrolide efficacy in legionellosis. Mean age was 58.3 years, 27.7% were women and Fine score was ≥ 4 in 35.8%. Among 253 patients who received quinolone monotherapy, 10 died (4.0%). Among 211 patients who received macrolide monotherapy, 23 died (10.9%). The pooled OR of death for treatment with a quinolone versus a macrolide was 0.5 (95% CI 0.2-1.3, n=8 studies, 464 patients). Length of stay was significantly shorter in the quinolone monotherapy group. The difference was 3.0 days (95% CI 0.7-5.3, P=0.001, n=3 studies, 263 patients). Neither of two tests for heterogeneity was significant (I (2)=0% for both, P=1). Other studied outcomes were not significantly different among treatment groups.
CONCLUSIONS
Few clinical data on legionellosis treatment are available. This first meta-analysis showed a trend toward a lower mortality rate and a significant decrease in length of hospital stay among patients receiving quinolones. These results must be confirmed by a randomized controlled trial.
Topics: Anti-Bacterial Agents; Humans; Legionellosis; Length of Stay; Macrolides; Quinolones; Survival Analysis; Treatment Outcome
PubMed: 24827889
DOI: 10.1093/jac/dku159 -
International Journal of Environmental... Jul 2018spp. is widespread in many natural and artificial water systems, such as hot water distribution networks, cooling towers, and spas. A particular risk factor has been...
spp. is widespread in many natural and artificial water systems, such as hot water distribution networks, cooling towers, and spas. A particular risk factor has been identified in the use of whirlpools and hot tubs in spa facilities and public baths. However, there has been no systematic synthesis of the published literature reporting legionellosis cases or outbreaks related to swimming/spa pools or similar environments used for recreational purposes (hot springs, hot tubs, whirlpools, natural spas). This study presents the results of a systematic review of the literature on cases and outbreaks associated with these environments. Data were extracted from 47 articles, including 42 events (17 sporadic cases and 25 outbreaks) and 1079 cases, 57.5% of which were diagnosed as Pontiac fever, without any deaths, and 42.5% were of Legionnaires' disease, with a fatality rate of 6.3%. The results are presented in relation to the distribution of species involved in the events, clinical manifestations and diagnosis, predisposing conditions in the patients, favourable environmental factors, and quality of the epidemiological investigation, as well as in relation to the different types of recreational water sources involved. Based on the epidemiological and microbiological criteria, the strength of evidence linking a case/outbreak of legionellosis with a recreational water system was classified as strong, probable, and possible; in more than half of the events the resulting association was strong.
Topics: Balneology; Disease Outbreaks; Health Resorts; Hot Springs; Humans; Legionellosis; Swimming Pools; Water Microbiology
PubMed: 30061526
DOI: 10.3390/ijerph15081612