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Journal of Hospital Medicine Aug 2022Guidelines recommend testing hospitalized patients with community-acquired pneumonia (CAP) for Legionella pneumophila only if the infection is severe or risk factors are...
BACKGROUND
Guidelines recommend testing hospitalized patients with community-acquired pneumonia (CAP) for Legionella pneumophila only if the infection is severe or risk factors are present. There are no validated models for predicting Legionella.
OBJECTIVE
To derive and externally validate a model to predict a positive Legionella test.
DESIGN, SETTING AND PARTICIPANTS
Diagnostic study of adult inpatients with pneumonia using data from 177 US hospitals in the Premier Healthcare Database (training and hold-out validation sets) and 12 Cleveland Clinic Health System (CCHS) hospitals (external validation set). We used multiple logistic regression to predict positive Legionella tests in the training set, and evaluated performance in both validation sets.
MAIN OUTCOME AND MEASURES
The outcome was a positive Legionella test. Potential predictors included demographics and co-morbidities, disease severity indicators, season, region, and presence of a local outbreak.
RESULTS
Of 166,689 patients hospitalized for pneumonia, 43,070 were tested for Legionella and 642 (1.5%) tested positive. The strongest predictors of a positive test were a local outbreak (odds ratio [OR], 3.4), June-October occurrence (OR, 3.4), hyponatremia (OR, 3.3), smoking (OR, 2.4), and diarrhea (OR, 2.0); prior admission within 6 months (OR, 0.27) and chronic pulmonary disease (OR, 0.49) were associated with a negative test. Model c-statistics were 0.79 in the Premier and 0.77 in the CCHS validation samples. High-risk patients were only slightly more likely to have been tested than lower-risk patients. Compared to actual practice, the model-based testing strategy detected twice as many cases.
CONCLUSIONS
Although Legionella is an uncommon cause of pneumonia, patient characteristics can identify individuals at high risk, allowing for more efficient testing.
Topics: Adult; Community-Acquired Infections; Humans; Legionella; Legionnaires' Disease; Pneumonia; Retrospective Studies
PubMed: 35880811
DOI: 10.1002/jhm.12919 -
Journal of Epidemiology and Community... Jun 2006Sharing of multi‐agency intelligence on cooling towers is needed for better prevention and control of outbreaks
Sharing of multi‐agency intelligence on cooling towers is needed for better prevention and control of outbreaks
Topics: Community-Acquired Infections; Disease Outbreaks; Humans; Industry; Legionnaires' Disease; Population Surveillance; United Kingdom
PubMed: 16698974
DOI: 10.1136/jech.2005.042366 -
BMC Infectious Diseases Jan 2021Legionnaire's disease is one of the major causes of community-acquired pneumonia and is occasionally complicated by neurological symptoms. However, reports of ocular...
BACKGROUND
Legionnaire's disease is one of the major causes of community-acquired pneumonia and is occasionally complicated by neurological symptoms. However, reports of ocular lesions due to Legionnaire's disease are limited.
CASE PRESENTATION
We report the case of a patient with Legionnaire's disease presenting as bilateral central scotomata due to retinal lesions. The patient consulted due to fever and bilateral central scotomata, as well as other extrapulmonary symptoms. Optical coherence tomography (OCT) showed bilateral accumulations of fluid under the retina, and the patient was diagnosed with bilateral exudative retinal detachment. Later, Legionnaire's disease was confirmed by pulmonary infiltrates on chest imaging and positive urinary antigen for Legionella pneumophila. After administration of antibiotics, the bilateral central scotomata and bilateral subretinal fluid accumulations completely resolved, as did the other extrapulmonary symptoms and the pulmonary infiltrates. Thus, the bilateral central scotomata due to exudative retinal detachment were thought to be caused by Legionnaire's disease.
CONCLUSIONS
This case demonstrates that Legionnaire's disease can present as bilateral central scotomata. We may consider the possibility of extrapulmonary involvement complicating Legionnaire's disease when we encounter bilateral ocular lesions in patients with fever and pneumonia.
Topics: Anti-Bacterial Agents; Humans; Legionella pneumophila; Legionnaires' Disease; Male; Middle Aged; Pneumonia, Bacterial; Scotoma; Tomography, Optical Coherence
PubMed: 33413170
DOI: 10.1186/s12879-020-05715-y -
Medical History Jan 2012Legionnaires' disease is now routinely discussed as an 'emerging infectious disease' (EID) and is said to be one of the earliest such diseases to be recognised. It first...
Legionnaires' disease is now routinely discussed as an 'emerging infectious disease' (EID) and is said to be one of the earliest such diseases to be recognised. It first appeared in 1976 and its cause was identified in 1977, the same year that Ebola fever, Hantaan virus and Campylobacter jejuni arrived. The designation of Legionnaires' disease as an EID was retrospective; it was not and could not be otherwise as the category only gained currency in the early 1990s. In this article we reflect on the changing medical understanding and social profile of Legionnaires' disease in the decade or so from its recognition to the creation of EIDs, especially its ambivalent position between public health and clinical medicine. However, we question any simple opposition, between public health experts who approached Legionnaires' disease as a new and worrying environmental threat that could be prevented, and clinicians who saw it as another cause of pneumonia that could be managed by improved diagnosis and treatment. We argue that in the British context of public spending cuts and the reform of public health, the category of 'new' diseases, in which Legionnaires' disease was central, was mobilised ahead of the EID lobby of the early 1990s, by interested groups in medicine to defend infectious diseases services.
Topics: Air Conditioning; Anti-Bacterial Agents; Attitude to Health; Communicable Diseases, Emerging; Disease Outbreaks; Health Facilities; History, 20th Century; Humans; Legionella pneumophila; Legionnaires' Disease; State Medicine; United Kingdom; Water Microbiology
PubMed: 23752984
DOI: 10.1017/S0025727300000284 -
An application for relating Legionella shower water monitoring results to estimated health outcomes.Water Research Aug 2022Exposure models are useful tools for relating environmental monitoring data to expected health outcomes. The objective of this study was to (1) compare two Legionella...
Exposure models are useful tools for relating environmental monitoring data to expected health outcomes. The objective of this study was to (1) compare two Legionella shower exposure models, and (2) develop a risk calculator tool for relating environmental monitoring data to estimated Legionella infection risks and Legionnaires' Disease (LD) illness risks. Legionella infection risks for a single shower event were compared using two shower Legionella exposure models. These models varied in their description of partitioning of Legionella in aerosols and aerosol deposition in the lung, where Model 1 had larger and fewer aerosol ranges than Model 2. Model 2 described conventional vs. water efficient showers separately, while Model 1 described exposure for an unspecified shower type (did not describe it as conventional or water efficient). A Monte Carlo approach was used to account for variability and uncertainty in these aerosolization and deposition parameters, Legionella concentrations, and the dose-response parameter. Methods for relating infection risks to illness risks accounting for demographic differences were used to inform the risk calculator web application ("app"). Model 2 consistently estimated higher infection risks than Model 1 for the same Legionella concentration in water and estimated deposited doses with less variability. For a 7.8-min shower with a Legionella concentration of 0.1 CFU/mL, the average infection risks estimated using Model 2 were 4.8 × 10 (SD=3.0 × 10) (conventional shower) and 2.3 × 10 (SD=1.7 × 10) (water efficient). Average infection risk estimated by Model 1 was 1.1 × 10 (SD=9.7 × 10). Model 2 was used for app development due to more conservative risk estimates and less variability in estimated dose. While multiple Legionella shower models are available for quantitative microbial risk assessments (QMRAs), they may yield notably different infection risks for the same environmental microbial concentration. Model comparisons will inform decisions regarding their integration with risk assessment tools. The development of risk calculator tools for relating environmental microbiology data to infection risks will increase the impact of exposure models for informing water treatment decisions and achieving risk targets.
Topics: Humans; Legionella; Legionella pneumophila; Legionellosis; Legionnaires' Disease; Outcome Assessment, Health Care; Respiratory Aerosols and Droplets; Water Microbiology; Water Supply
PubMed: 35816914
DOI: 10.1016/j.watres.2022.118812 -
Frontiers in Cellular and Infection... 2021Legionellales-infected water is a frequent cause of local outbreaks of Legionnaires' disease and Pontiac fever. Decontaminations are difficult because Legionellales...
Legionellales-infected water is a frequent cause of local outbreaks of Legionnaires' disease and Pontiac fever. Decontaminations are difficult because Legionellales reproduce in eukaryotic microorganisms (protists). Most often, Legionellales have been isolated from amoebae; however, the culture-based sampling methods are taxonomically biased. Sequencing studies show that amoebae in the cercozoan class Thecofilosea are dominant in soils and wastewater treatment plants, prompting us to screen their capability to serve as potential hosts of endosymbiotic bacteria. Environmental isolates of Thecofilosea contained a surprising richness of endosymbiotic Legionellales, including . Considering the widespread dispersal of Legionellales in apparently unrelated amoeboid protist taxa, it appears that the morphotype and not the evolutionary origin of amoebae determines their suitability as hosts for Legionellales. We further provide a protocol for gnotobiotic cultivation of Legionellales and their respective hosts, facilitating future genomic and transcriptomic research of host-symbiont relationships.
Topics: Amoeba; Amoebida; Bacteria; Humans; Legionella; Legionnaires' Disease
PubMed: 33763389
DOI: 10.3389/fcimb.2021.642216 -
Emerging Infectious Diseases Jan 2021Through the use of published estimates of medical costs and new calculations of productivity losses, we estimate the lifetime economic burden of 2014 Legionnaires'...
Through the use of published estimates of medical costs and new calculations of productivity losses, we estimate the lifetime economic burden of 2014 Legionnaires' disease cases in the United States at ≈$835 million. This total includes $21 million in productivity losses caused by absenteeism and $412 million in productivity losses caused by premature deaths.
Topics: Cost of Illness; Humans; Legionnaires' Disease; United States
PubMed: 33350911
DOI: 10.3201/eid2701.191198 -
Internal Medicine (Tokyo, Japan) 2009Legionella pneumonia typically presents as lobar pneumonia with multiple-lobe involvement, but Legionella lung abscess is rare. To identify the predisposing factors for... (Review)
Review
Legionella pneumonia typically presents as lobar pneumonia with multiple-lobe involvement, but Legionella lung abscess is rare. To identify the predisposing factors for Legionella abscess, we analyzed 62 of the 79 case reports on Legionella abscess found in literature; 28 (45.2%) were of hospital-acquired infection and 28 (45.2%), community-acquired infection. Seventeen patients (27.4%) died. L. pneumophila serogroup 1 was the most common, but other serogroups of L. pneumophila, L. micdadei, L. bozemanii, L. dumoffii, and L. maceachernii were also isolated from the abscess. Corticosteroids were administered for underlying diseases to 43 (69.4%) patients. Peripheral neutrophil counts were higher in patients with abscess than in those with only pulmonary infiltration. In certain cases, Legionella abscess developed during neutropenia recovery. However, lymphocyte counts were low in most cases. Clinical factors like corticosteroid treatment, which causes impaired cellular immunity and subsequent neutrophil accumulation in the lesion, might function as predisposing factors for Legionella abscess.
Topics: Animals; Humans; Immunocompromised Host; Legionella; Legionnaires' Disease; Lung Abscess
PubMed: 19952481
DOI: 10.2169/internalmedicine.48.2647 -
Emerging Infectious Diseases Jul 2018Two cases of Legionnaires' disease and 1 of Pontiac fever occurred among the crew of a merchant ship operating off the shores of Australia. PCR assays identified...
Two cases of Legionnaires' disease and 1 of Pontiac fever occurred among the crew of a merchant ship operating off the shores of Australia. PCR assays identified potential sources in the ship's cabins. Modification of maritime regulations for Legionnaires' disease prevention in commercial vessels is needed for nonpassenger merchant ships.
Topics: Australia; Disease Outbreaks; History, 21st Century; Humans; Indian Ocean; Legionellosis; Legionnaires' Disease; Middle Aged; Seasons; Ships; Travel-Related Illness
PubMed: 29912714
DOI: 10.3201/eid2407.171978 -
Emerging Infectious Diseases Jun 2019We report national surveillance of Legionnaires' disease in China. Urine samples from 11 (3.85%) of 286 patients with severe pneumonia of unknown cause were positive for...
We report national surveillance of Legionnaires' disease in China. Urine samples from 11 (3.85%) of 286 patients with severe pneumonia of unknown cause were positive for the Legionella pneumophila serogroup 1 antigen. We isolated Legionella strains from 7 patients. Improved diagnostic testing is needed for this underestimated disease in China.
Topics: Adult; Aged; Antigens, Bacterial; China; Female; Humans; Legionella pneumophila; Legionnaires' Disease; Male; Microbial Sensitivity Tests; Middle Aged; Molecular Typing; Public Health Surveillance; Serogroup; Young Adult
PubMed: 31107214
DOI: 10.3201/eid2506.171431