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The International Journal of... Dec 2023A case admitted with dysarthria and syncope and hyperintense lesion in the splenium of the corpus callosum, diagnosed as Legionnaires' disease by detecting Legionella...
PURPOSE/AIM OF THE STUDY
A case admitted with dysarthria and syncope and hyperintense lesion in the splenium of the corpus callosum, diagnosed as Legionnaires' disease by detecting Legionella antigen in the urine, and recovered only with antibiotic treatment is presented because it is rare in the literature.
MATERIALS AND METHODS
When a 64-year-old female patient was admitted to the emergency department with complaints of sudden loss of consciousness and fainting at home, she had speech impairment, and her pulse oxygen saturation in room air was 88%. In the neurological examination, there was no pathological finding except dysarthria in the patient with no motor deficit. The patient had no respiratory complaints and had a recent travel history. In laboratory examinations, hyponatremia was detected with increased C-reactive protein and liver enzymes. Consolidation was observed in the lower right zone on chest computed tomography. Ampicillin + sulbactam (4x1 gr, intravenous) and clarithromycin (2 × 500 mg orally) were initiated. On cranial magnetic resonance, a hyperintense lesion was observed in the splenium of the corpus callosum in the oval T2 sequence. serogroup 1 antigen in urine was reported as positive. On the fourth day of her hospitalization, the patient, whose CRP and liver enzyme values regressed, her hyponatremia improved, her pulse oxygen saturation increased to 92% in room air, and her speech became comprehensible, was discharged after oral antibiotic treatment was arranged. On the 12 day, the speech ability of the patient completely returned to normal.
CONCLUSION
Legionella infection should be suspected in the presence of pneumonia and corpus callosum splenium lesion.
PubMed: 38060476
DOI: 10.1080/00207454.2023.2292952 -
Public Health Reports (Washington, D.C.... 2022Racial and socioeconomic disparities in the incidence of Legionnaires' disease have been documented for the past 2 decades; however, the social determinants of health... (Review)
Review
OBJECTIVES
Racial and socioeconomic disparities in the incidence of Legionnaires' disease have been documented for the past 2 decades; however, the social determinants of health (SDH) that contribute to these disparities are not well studied. The objective of this narrative review was to characterize SDH to inform efforts to reduce disparities in the incidence of Legionnaires' disease.
METHODS
We conducted a narrative review of articles published from January 1979 through October 2019 that focused on disparities in the incidence of Legionnaires' disease and pneumonia (inclusive of bacterial pneumonia and/or community-acquired pneumonia) among adults and children (excluding articles that were limited to people aged <18 years). We identified 220 articles, of which 19 met our criteria: original research, published in English, and examined Legionnaires' disease or pneumonia, health disparities, and SDH. We organized findings using the Healthy People 2030 SDH domains: economic stability, education access and quality, social and community context, health care access and quality, and neighborhood and built environment.
RESULTS
Of the 19 articles reviewed, multiple articles examined disparities in incidence of Legionnaires' disease and pneumonia related to economic stability/income (n = 13) and comorbidities (n = 10), and fewer articles incorporated SDH variables related to education (n = 3), social support (none), health care access (n = 1), and neighborhood and built environment (n = 6) in their analyses.
CONCLUSIONS
Neighborhood and built-environment factors such as housing, drinking water infrastructure, and pollutant exposures represent critical partnership and research opportunities. More research that incorporates SDH and multilevel, cross-sector interventions is needed to address disparities in Legionnaires' disease incidence.
Topics: Adult; Child; Community-Acquired Infections; Humans; Incidence; Legionnaires' Disease; Pneumonia; Social Determinants of Health
PubMed: 34185609
DOI: 10.1177/00333549211026781 -
Journal of Molecular Biology Oct 2019Legionella pneumophila is the causative agent of the severe pneumonia Legionnaires' disease. L. pneumophila is ubiquitously found in freshwater environments, where it... (Review)
Review
Legionella pneumophila is the causative agent of the severe pneumonia Legionnaires' disease. L. pneumophila is ubiquitously found in freshwater environments, where it replicates within free-living protozoa. Aerosolization of contaminated water supplies allows the bacteria to be inhaled into the human lung, where L. pneumophila can be phagocytosed by alveolar macrophages and replicate intracellularly. The Dot/Icm type IV secretion system (T4SS) is one of the key virulence factors required for intracellular bacterial replication and subsequent disease. The Dot/Icm apparatus translocates more than 300 effector proteins into the host cell cytosol. These effectors interfere with a variety of cellular processes, thus enabling the bacterium to evade phagosome-lysosome fusion and establish an endoplasmic reticulum-derived Legionella-containing vacuole, which facilitates bacterial replication. In turn, the immune system has evolved numerous strategies to recognize intracellular bacteria such as L. pneumophila, leading to potent inflammatory responses that aid in eliminating infection. This review aims to provide an overview of L. pneumophila pathogenesis in the context of the host immune response.
Topics: Animals; Cytokines; Endoplasmic Reticulum; Humans; Legionella pneumophila; Legionnaires' Disease; Macrophages, Alveolar
PubMed: 31351897
DOI: 10.1016/j.jmb.2019.07.028 -
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 -
MBio Jun 2021The Dot/Icm type IV secretion system (T4SS) of Legionella pneumophila is essential for lysosomal evasion and permissiveness of macrophages for intracellular...
The Dot/Icm type IV secretion system (T4SS) of Legionella pneumophila is essential for lysosomal evasion and permissiveness of macrophages for intracellular proliferation of the pathogen. In contrast, we show that polymorphonuclear cells (PMNs) respond to a functional Dot/Icm system through rapid restriction of L. pneumophila. Specifically, we show that the L. pneumophila T4SS-injected amylase (LamA) effector catalyzes rapid glycogen degradation in the PMNs cytosol, leading to cytosolic hyperglucose. Neutrophils respond through immunometabolic reprogramming that includes upregulated aerobic glycolysis. The PMNs become activated with spatial generation of intracellular reactive oxygen species within the -containing phagosome (LCP) and fusion of specific and azurophilic granules to the LCP, leading to rapid restriction of L. pneumophila. We conclude that in contrast to macrophages, PMNs respond to a functional Dot/Icm system, and specifically to the effect of the injected amylase effector, through rapid engagement of major microbicidal processes and rapid restriction of the pathogen. Legionella pneumophila is commonly found in aquatic environments and resides within a wide variety of amoebal hosts. Upon aerosol transmission to humans, L. pneumophila invades and replicates with alveolar macrophages, causing pneumonia designated Legionnaires' disease. In addition to alveolar macrophages, neutrophils infiltrate into the lungs of infected patients. Unlike alveolar macrophages, neutrophils restrict and kill L. pneumophila, but the mechanisms were previously unclear. Here, we show that the pathogen secretes an amylase (LamA) enzyme that rapidly breakdowns glycogen stores within neutrophils, and this triggers increased glycolysis. Subsequently, the two major killing mechanisms of neutrophils, granule fusion and production of reactive oxygen species, are activated, resulting in rapid killing of L. pneumophila.
Topics: Bacterial Proteins; Cytosol; Glycogen; Glycolysis; Humans; Legionella pneumophila; Legionnaires' Disease; Neutrophils; Phagosomes; Reactive Oxygen Species; Type IV Secretion Systems
PubMed: 34076467
DOI: 10.1128/mBio.01008-21 -
The Journal of the Association of... Mar 2024has a higher prevalence in India than in the world. Legionaries' disease most commonly involves the lungs but because of increased awareness, extrapulmonary...
BACKGROUND
has a higher prevalence in India than in the world. Legionaries' disease most commonly involves the lungs but because of increased awareness, extrapulmonary manifestations are also being diagnosed more frequently.
CASE DESCRIPTION
We present a case of a young female with acute onset of fever and chest pain. On initial investigation, an electrocardiogram (ECG) reported widespread pulse rate (PR) depression suggestive of pericarditis which was confirmed by ECG. High-resolution computed tomography (HRCT) thorax suggested mild bilateral pleural effusion with normal lung parenchyma. elevated erythrocyte sedimentation rate (ESR), C-reactive protein (CRP) added to the diagnosis of serositis. Serological study for atypical organisms was remarkable for positive immunoglobulin M (IgM) for . She was treated with a high dose of steroids and azithromycin successfully.
CONCLUSION
Isolated extrapulmonary presentation of legionaries disease is often overlooked and is common. So it should be always included in the diagnostic armamentarium as treatment is highly efficacious if started early.
Topics: Humans; Female; Serositis; Azithromycin; Adult; Anti-Bacterial Agents; Legionellosis; Legionella; Electrocardiography; Tomography, X-Ray Computed; Legionnaires' Disease
PubMed: 38736126
DOI: 10.59556/japi.72.0361 -
Nature Communications Nov 2023Legionella pneumophila (LP) secretes more than 300 effectors into the host cytosol to facilitate intracellular replication. One of these effectors, SidH, 253 kDa in...
Legionella pneumophila (LP) secretes more than 300 effectors into the host cytosol to facilitate intracellular replication. One of these effectors, SidH, 253 kDa in size with no sequence similarity to proteins of known function is toxic when overexpressed in host cells. SidH is regulated by the LP metaeffector LubX which targets SidH for degradation in a temporal manner during LP infection. The mechanism underlying the toxicity of SidH and its role in LP infection are unknown. Here, we determined the cryo-EM structure of SidH at 2.7 Å revealing a unique alpha helical arrangement with no overall similarity to known protein structures. Surprisingly, purified SidH came bound to a E. coli EF-Tu/t-RNA/GTP ternary complex which could be modeled into the cryo-EM density. Mutation of residues disrupting the SidH-tRNA interface and SidH-EF-Tu interface abolish the toxicity of overexpressed SidH in human cells, a phenotype confirmed in infection of Acanthamoeba castellani. We also present the cryo-EM structure of SidH in complex with a U-box domain containing ubiquitin ligase LubX delineating the mechanism of regulation of SidH. Our data provide the basis for the toxicity of SidH and into its regulation by the metaeffector LubX.
Topics: Humans; Legionella pneumophila; Escherichia coli; Peptide Elongation Factor Tu; Legionnaires' Disease; Ubiquitin-Protein Ligases; Bacterial Proteins
PubMed: 37923743
DOI: 10.1038/s41467-023-42683-8 -
Journal of Medical Case Reports Jun 2023Infections have been recognized as an uncommon cause of rhabdomyolysis, with evidence indicating a worse prognosis when compared to rhabdomyolysis caused by other...
BACKGROUND
Infections have been recognized as an uncommon cause of rhabdomyolysis, with evidence indicating a worse prognosis when compared to rhabdomyolysis caused by other etiologies. Diseases caused by Legionella pneumophila can present variably, ranging from mild to severe illness, as is sometimes the case with pneumonia. In particular, the triad of Legionnaire's disease, rhabdomyolysis, and acute kidney injury is associated with a significant increase in the morbidity and mortality, with most patients requiring initiation of renal replacement therapy such as hemodialysis. While the exact mechanism of both the muscle and kidney injury in this setting remains unknown, several hypotheses exist, with some research suggesting multiple yet distinct processes occurring in both target organs.
CASE PRESENTATION
In this case report, we describe a 53-year-old African American man who presented with Legionella pneumophila pneumonia complicated by rhabdomyolysis and acute kidney injury. He was treated with aggressive fluid resuscitation and a 2-week course of azithromycin. His clinical status improved without necessitating renal replacement therapy or mechanical ventilation. We postulate that early recognition and treatment were key to his recovery. He was discharged 10 days later without recurrence of rhabdomyolysis at the time of this report.
CONCLUSION
While there are several well-established and more common causes of rhabdomyolysis, clinicians should recognize Legionella sp. as an etiology, given its association with significant morbidity and mortality.
Topics: Male; Humans; Middle Aged; Legionella; Legionnaires' Disease; Pneumonia; Acute Kidney Injury; Rhabdomyolysis
PubMed: 37344851
DOI: 10.1186/s13256-023-04000-1 -
Nursing Mar 2020
Topics: Guidelines as Topic; Health Facilities; Humans; Legionnaires' Disease; Risk Factors; Water Supply
PubMed: 32068708
DOI: 10.1097/01.NURSE.0000651660.70883.b4 -
European Journal of Cell Biology Dec 2023The study of virulence of Legionella pneumophila and its interactions with its hosts has been predominantly conducted in cellulo in the past decades. Although easy to... (Review)
Review
The study of virulence of Legionella pneumophila and its interactions with its hosts has been predominantly conducted in cellulo in the past decades. Although easy to implement and allowing the dissection of molecular pathways underlying host-pathogen interactions, these cellular models fail to provide conditions of the complex environments encountered by the bacteria during the infection of multicellular organisms. To improve our understanding of human infection, several animal models have been developed. This review provides an overview of the invertebrate and vertebrate models that have been established to study L. pneumophila infection and that are alternatives to the classical mouse model, which does not recall human infection with L. pneumophila well. Finally we provide insight in the main contributions made by these models along with their pros and cons.
Topics: Animals; Mice; Humans; Legionnaires' Disease; Legionella pneumophila; Invertebrates; Vertebrates; Disease Models, Animal
PubMed: 37926040
DOI: 10.1016/j.ejcb.2023.151369