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Medicina (Kaunas, Lithuania) Jan 2024: Legionnaires' disease (LD) is an acute respiratory disease with increasing annual numbers of reported domestic and global cases. This study aimed to establish...
: Legionnaires' disease (LD) is an acute respiratory disease with increasing annual numbers of reported domestic and global cases. This study aimed to establish foundational data for the prevention and control of LD by investigating the occurrence and infection routes of reported and suspected cases of LD in Gyeonggi Province, Korea, from January 2016 to December 2022, and by and analyzing the risk factors for death. : A sex-and-age standardization was performed on LD patients and suspected cases reported in Gyeonggi Province. The monthly average number of confirmed cases was visualized using graphs, and a survival analysis was performed using Kaplan-Meier survival curves. The mortality risk ratio was estimated using the Cox proportional hazards model. : The incidence of LD in Gyeonggi Province mirrored the national trend, peaking in July with the highest number of confirmed and suspected cases. While there was no significant difference in survival rates by age, the survival rate was higher for suspected cases when analyzed separately. Comparing the death ratio by infection route, nosocomial infections showed the highest death ratio, and intensive care unit (ICU) admission and the presence of coinfections were significantly correlated with mortality. Factors such as nosocomial infection, admission within 1 to 3 days following diagnosis, and the development of complications were factors contributing to a higher risk of death. : The general characteristics of patients with LD were similar to those suggested by previous studies. The proportion of community-acquired infections was lower than in previous studies, but the length of hospital stay was similar for survivors and the deceased, and the mortality rate within 30 days after diagnosis was higher for nosocomial infections. In conclusion, nosocomial infection, a period of up to 3 days from admission to diagnosis, and complications were significantly related to the mortality rate of LD.
Topics: Humans; Legionnaires' Disease; Legionella pneumophila; Cross Infection; Epidemiologic Studies; Risk Factors; Republic of Korea
PubMed: 38399516
DOI: 10.3390/medicina60020227 -
Journal of Infection and Chemotherapy :... Sep 2023Legionella pneumophila is an important cause of pneumonia, however there is scant literature assessing the therapeutic benefit of corticosteroids in treatment. We sought...
INTRODUCTION
Legionella pneumophila is an important cause of pneumonia, however there is scant literature assessing the therapeutic benefit of corticosteroids in treatment. We sought to investigate the association between corticosteroid use and in-hospital mortality for patients hospitalized with Legionella pneumonia.
METHODS
Data was collected retrospectively from January 2012 to July 2019 at a 705 bed hospital in New York City. Patients were included if they received a positive Legionella test. Exclusion criteria included age <18, concurrent immunosuppression, and HIV diagnosis. We assessed the relationship between corticosteroid use and in-hospital mortality. Statistical analyses were performed in RStudio.
RESULTS
The study included 160 patients, among which 32 (20%) received steroids. Overall mortality was 7.5% (12.5% among steroid recipients, 6.2% among controls). 25% of patients were admitted to the ICU (37.5% among steroid recipients, 21.9% among controls). Adjusted analysis showed steroid recipients did not have significantly different mortality (aOR = 2.56, p = 0.436). Steroid use was not significantly associated with longer LOS (p = 0.22). Steroid use was significantly associated with hyperglycemia (aOR = 2.91, p = 0.018) and GI bleed (OR = 9.0, p = 0.014).
CONCLUSIONS
We found that in patients hospitalized with Legionella pneumonia, corticosteroid administration was not significantly associated with longer hospitalization or mortality. All findings held true when adjusting for known predictors of pneumonia severity. Corticosteroid use was associated with increased rates of hyperglycemia and GIB requiring blood transfusion. The results of this study are consistent with guidelines recommending against routine use of corticosteroids in CAP.
Topics: Humans; Retrospective Studies; Legionnaires' Disease; Pneumonia; Adrenal Cortex Hormones; Legionella; Steroids; Hyperglycemia; Community-Acquired Infections
PubMed: 37164062
DOI: 10.1016/j.jiac.2023.05.002 -
Infection and Immunity Nov 2023The host type I interferon (IFN) response protects against infections. Other bacterial pathogens inhibit type I IFN-mediated cell signaling; however, the interaction...
The host type I interferon (IFN) response protects against infections. Other bacterial pathogens inhibit type I IFN-mediated cell signaling; however, the interaction between this signaling pathway and has not been well described. Here, we demonstrate that inhibits the IFN-β signaling pathway but does not inhibit IFN-γ-mediated cell signaling. The addition of IFN-β to -infected macrophages limited bacterial growth independently of NOS2 and reactive nitrogen species. The type IV secretion system of is required to inhibit IFN-β-mediated cell signaling. Finally, we show that the inhibition of the IFN-β signaling pathway occurs downstream of STAT1 and STAT2 phosphorylation. In conclusion, our findings describe a novel host cell signaling pathway inhibited by via its type IV secretion system.
Topics: Humans; Legionella pneumophila; Type IV Secretion Systems; Interferon-gamma; Legionnaires' Disease; Signal Transduction; Interferon Type I
PubMed: 37843413
DOI: 10.1128/iai.00365-23 -
Characterization of a family I inorganic pyrophosphatase from Legionella pneumophila Philadelphia 1.Acta Crystallographica. Section F,... Oct 2023Inorganic pyrophosphate (PP) is generated as an intermediate or byproduct of many fundamental metabolic pathways, including DNA/RNA synthesis. The intracellular...
Inorganic pyrophosphate (PP) is generated as an intermediate or byproduct of many fundamental metabolic pathways, including DNA/RNA synthesis. The intracellular concentration of PP must be regulated as buildup can inhibit many critical cellular processes. Inorganic pyrophosphatases (PPases) hydrolyze PP into two orthophosphates (P), preventing the toxic accumulation of the PP byproduct in cells and making P available for use in biosynthetic pathways. Here, the crystal structure of a family I inorganic pyrophosphatase from Legionella pneumophila is reported at 2.0 Å resolution. L. pneumophila PPase (LpPPase) adopts a homohexameric assembly and shares the oligonucleotide/oligosaccharide-binding (OB) β-barrel core fold common to many other bacterial family I PPases. LpPPase demonstrated hydrolytic activity against a general substrate, with Mg being the preferred metal cofactor for catalysis. Legionnaires' disease is a severe respiratory infection caused primarily by L. pneumophila, and thus increased characterization of the L. pneumophila proteome is of interest.
Topics: Humans; Legionella pneumophila; Inorganic Pyrophosphatase; Crystallography, X-Ray; Legionnaires' Disease
PubMed: 37728609
DOI: 10.1107/S2053230X23008002 -
Letters in Applied Microbiology Jul 2023Legionella longbeachae is an important cause of Legionnaires' disease in Australasia and is associated with exposure to potting soils. Our aim was to identify ways to...
Legionella longbeachae is an important cause of Legionnaires' disease in Australasia and is associated with exposure to potting soils. Our aim was to identify ways to reduce the load of L. longbeachae in potting soils. Inductively-coupled plasma optical emission spectrometry (ICP-OES) of an all-purpose potting mix showed copper (Cu) concentrations (mg/kg) range from 15.8 to 23.6. Zinc (Zn) and manganese (Mn) were significantly higher than Cu ranging from 88.6-106 to 171-203, respectively. Minimal inhibitory and bactericidal concentrations of 10 salts used in the horticultural industry were determined for Legionella species in buffered yeast extract (BYE) broth. For L. longbeachae (n = 9) the median (range) minimum inhibitory concentration (MIC) (mg/L) of copper sulfate was 31.25 (15.6-31.25), zinc sulfate 31.25 (7.81-31.25), and manganese sulfate 31.25 (7.81-62.5). The MIC and minimum bactericidal concentration (MBC) were within one dilution of each other. Susceptibility to Cu and Zn salts increased as the concentration of pyrophosphate iron in the media decreased. The MIC values for these three metals against Legionella pneumophila (n = 3) and Legionella micdadei (n = 4) were similar. Combinations of Cu, Zn, and Mn were additive. Legionella longbeachae has similar susceptibility to Cu and other metal ions in comparison to L. pneumophila.
Topics: Humans; Legionella longbeachae; Copper; Manganese; Zinc; Salts; Legionnaires' Disease; Legionella; Soil
PubMed: 37403323
DOI: 10.1093/lambio/ovad074 -
The Journal of Hospital Infection Aug 2023Rapid monitoring of Legionella pneumophila (Lp) is essential to reduce the risk of Legionnaires' disease in healthcare facilities. However, culture results take at least...
BACKGROUND
Rapid monitoring of Legionella pneumophila (Lp) is essential to reduce the risk of Legionnaires' disease in healthcare facilities. However, culture results take at least eight days, delaying the implementation of corrective measures. Here, we assessed the performance of a qPCR method and determined qPCR action thresholds for the detection of Lp in hospital hot water networks (HWNs).
METHODS
Hot water samples (N = 459) were collected from a hospital HWN. Lp were quantified using iQ-Check® Quanti real-time PCR Quantification kits (Bio-Rad) and the results were compared with those of culture. qPCR thresholds corresponding to the culture action thresholds of 10 and 1000 cfu/L were determined on a training dataset and validated on an independent dataset.
RESULTS
Lp concentrations measured by culture and qPCR were correlated for both the training dataset (Spearman's correlation coefficient ρ = 0.687, P<0.0001) and the validation dataset (ρ = 0.661, P<0.0001). Lp qPCR positivity thresholds corresponding to culture action thresholds of 10 cfu/L was 91 genome units (gu) per litre (sensitivity, 86.4%; negative predictive value - NPV, 93.3%) and that corresponding to culture action thresholds of 1000 cfu/L was 1048 gu/L (sensitivity, 100%; NPV, 100%).
CONCLUSION
Detection of Lp by qPCR could be implemented with confidence in hospitals as a complement to culture in the monitoring strategy to speed up the implementation of corrective measures.
Topics: Humans; Legionella pneumophila; Real-Time Polymerase Chain Reaction; Water; Legionnaires' Disease; Water Microbiology; Hospitals; Legionella
PubMed: 37353007
DOI: 10.1016/j.jhin.2023.06.010 -
Research Square Sep 2023Ubiquitination is a crucial posttranslational modification in eukaryotes that plays a significant role in the infection of intracellular microbial pathogens, such as...
Ubiquitination is a crucial posttranslational modification in eukaryotes that plays a significant role in the infection of intracellular microbial pathogens, such as the bacterium responsible for Legionnaires' disease. While the -containing vacuole (LCV) is coated with ubiquitin (Ub), it avoids recognition by autophagy adaptors. In this study, we report that the Sdc and Sde families of effectors work together to build ubiquitinated species around the LCV. The Sdc effectors catalyze canonical polyubiquitination directly on host targets or on the phosphoribosyl-Ub (PR-Ub) conjugated to host targets by Sde. Remarkably, the Ub moieties within the poly-Ub chains are either modified with a phosphoribosyl group by Sde and other PDE domain-containing effectors or covalently attached to other host substrates via Sde-mediated PR-ubiquitination. Furthermore, these modifications prevent the recognition by Ub adaptors, such as p62, and therefore exclude host autophagy adaptors from the LCV. Our findings shed light on the nature of the poly-ubiquitinated species present at the surface of the LCV and provide a molecular mechanism for the avoidance of autophagy adaptors by the Ub-decorated LCV.
PubMed: 37790579
DOI: 10.21203/rs.3.rs-3266941/v1 -
Progress in Community Health... 2024The Flint water crisis (FWC) was a public health tragedy caused by crumbling infrastructure, subverted democracy, and indifference toward a predominantly poor and Black...
BACKGROUND
The Flint water crisis (FWC) was a public health tragedy caused by crumbling infrastructure, subverted democracy, and indifference toward a predominantly poor and Black community that resulted in lead-in-water exposure, Legionnaires' disease, and emotional and health-related trauma. Through the cooperation of community partners, the Flint Registry (FR) was conceived to track long-term health and improve public health via service connections.
OBJECTIVES
This study sought to share the FR's community-partnered, multi-tiered engagement strategy and determine the efficacy of this strategy to engage the community and reach Flint residents.
METHODS
Community engagement and impact were measured by collecting and describing feedback from the community engagement strategies and by comparing the demographics of the enrollees recruited through community-engaged recruitment (CER) and non-CER methods. Enroll-ees indicated how they heard about the FR; CER involved direct interaction with a community member.
RESULTS
Community engagement strategies incorporated approximately 1,200 people and 7 funded organizations, impacting 22 key areas of FR design and implementation. More than 50% of enrollees heard about the FR through CER methods. They were, on average, more likely to be younger, female, Black/African American, and living outside of Flint during the FWC.
CONCLUSIONS
Community engagement elevated voices of those impacted by the FWC. CER methods were as effective as non-CER methods. Although there were no differences in screened measures of social vulnerability, there were in age, gender, and race. CER methods may increase participation and build trust in populations which historically are hesitant to participate in public health efforts.
Topics: Humans; Female; Male; Registries; Community-Based Participatory Research; Adult; Middle Aged; Florida; Community Participation; Adolescent; Young Adult; Aged; Community-Institutional Relations
PubMed: 38946562
DOI: No ID Found -
Clinical Case Reports Mar 2024Legionnaires' disease, often presenting as pneumonia, can uncommonly manifest with extrapulmonary symptoms such as cerebellar involvement and rhabdomyolysis. This case...
KEY CLINICAL MESSAGE
Legionnaires' disease, often presenting as pneumonia, can uncommonly manifest with extrapulmonary symptoms such as cerebellar involvement and rhabdomyolysis. This case emphasizes the successful resolution of dysarthria and renal dysfunction with prompt Legionella treatment, underscoring the importance of vigilance for diverse manifestations in Legionella infections.
ABSTRACT
Legionnaires' disease usually presents with pneumonia and a few extrapulmonary manifestations, such as neurological, musculoskeletal, and cutaneous manifestations. However, cerebellar involvement and rhabdomyolysis as an association with Legionella are not frequently encountered. We present a case of Legionella-induced rhabdomyolysis requiring hemodialysis and dysarthria that resolved with Legionella treatment.
PubMed: 38464574
DOI: 10.1002/ccr3.8628 -
MMWR. Morbidity and Mortality Weekly... Dec 2023Legionnaires disease is a serious infection acquired by inhalation of water droplets from human-made building water systems that contain Legionella bacteria. On July 11...
Legionnaires disease is a serious infection acquired by inhalation of water droplets from human-made building water systems that contain Legionella bacteria. On July 11 and 12, 2022, Napa County Public Health (NCPH) in California received reports of three positive urinary antigen tests for Legionella pneumophila serogroup 1 in the town of Napa. By July 21, six Legionnaires disease cases had been confirmed among Napa County residents, compared with a baseline of one or two cases per year. NCPH requested assistance from the California Department of Public Health (CDPH) and CDC to aid in the investigations. Close temporal and geospatial clustering permitted a focused environmental sampling strategy of high-risk facilities which, coupled with whole genome sequencing results from samples and investigation of water system maintenance, facilitated potential linking of the outbreak with an environmental source. NCPH, with technical support from CDC and CDPH, instructed and monitored remediation practices for all environmental locations that tested positive for Legionella. The investigation response to this community outbreak illustrates the importance of interdisciplinary collaboration by public health agencies, laboratory support, timely communication with the public, and cooperation of managers of potentially implicated water systems. Timely identification of possible sources, sampling, and remediation of any facility testing positive for Legionella is crucial to interrupting further transmission.
Topics: Humans; Legionnaires' Disease; Legionella pneumophila; Legionella; Disease Outbreaks; Water Microbiology; California; Water
PubMed: 38060434
DOI: 10.15585/mmwr.mm7249a1