Evaluating Fourier-transform infrared spectroscopy with IR Biotyper as a faster and simpler method for investigating the sources of an outbreak of legionellosis.

Fourier-transform infrared (FTIR) spectroscopy using the IR Biotyper and core genome single nucleotide polymorphism (cgSNP) analysis were performed on 12 Legionella isolates associated with an outbreak at a spa house in Kanagawa Prefecture, Japan, and 3 non-outbreak isolates. The discriminative power of FTIR spectroscopy for 48-h incubation conditions of L. pneumophila in this outbreak was lower than cgSNP-based typing but higher than serogroup typing. FTIR spectroscopy could screen outbreak isolates from a group of genetically related isolates and may be useful as an initial typing method in Legionella outbreak investigations.

Legionella Serositis: A Rare Presentation.

BACKGROUND: Legionella 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 Legionella. 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.

Increased Incidence of Legionellosis after Improved Diagnostic Methods, New Zealand, 2000-2020.

Legionellosis, notably Legionnaires' disease, is recognized globally and in New Zealand (Aotearoa) as a major cause of community-acquired pneumonia. We analyzed the temporal, geographic, and demographic epidemiology and microbiology of Legionnaires' disease in New Zealand by using notification and laboratory-based surveillance data for 2000‒2020. We used Poisson regression models to estimate incidence rate ratios and 95% CIs to compare demographic and organism trends over 2 time periods (2000-2009 and 2010-2020). The mean annual incidence rate increased from 1.6 cases/100,000 population for 2000-2009 to 3.9 cases/100,000 population for 2010-2020. This increase corresponded with a change in diagnostic testing from predominantly serology with some culture to almost entirely molecular methods using PCR. There was also a marked shift in the identified dominant causative organism, from Legionella pneumophila to L. longbeachae. Surveillance for legionellosis could be further enhanced by greater use of molecular typing of isolates.

Legionella micdadei Aquaticum Infection: a Case Report and Literature Review.

BACKGROUND: The goal of the study was to analyze the clinical characteristics of Legionella cases caused by Legionella micdadei and explore the diagnosis and treatment. METHODS: The pathogen was identified by routine isolation and culture, biochemical identification, serum agglutination test, mass spectrometry identification, and routine PCR. Combined with the related literature review, the clinical diagnosis and treatment of Legionella micdadei were analyzed. RESULTS: The patient suffered from pulmonary infection caused by Legionella micdadei. After treatment with moxi-floxacin for 2 weeks, the body temperature dropped and the shadow of the lung was completely absorbed after 2 months. Combined with literature analysis, 8 cases of Legionella micetidis, including 7 males and 1 female, aged from 27 to 57 years old, 6 cases with basic diseases, which were treated with azithromycin, erythromycin or levofloxacin, and all of them achieved good therapeutic effect. CONCLUSIONS: The detection of Legionella should be strengthened in patients with pneumonia whose symptoms have no obvious improvement after antibiotic treatment. Azithromycin, erythromycin or levofloxacin are effective in the treatment of Legionella spp.

National survey of physicians in Japan regarding their use of diagnostic tests for legionellosis.

INTRODUCTION: Bacterial culture remains the gold standard for the diagnosis of legionellosis. However, past reports indicate that most physicians use the urinary antigen test (UAT) alone. Combining it with other tests is important, especially in patients with negative UAT results. The aim of this study was to investigate the current situation of legionellosis diagnostics and clarify the issues that need to be addressed. METHODS: Between March 1, 2021 and April 30, 2021, a questionnaire survey was conducted in an anonymous manner among physicians working in Japan. Questionnaires were generated on a website and asked questions in a multiple-choice format. RESULTS: Valid responses were received from 309 physicians during the study period. Most (92.9%) physicians reported using UAT as the initial test for patients suspected of having legionellosis, and <10% reported using other tests (e.g., culture, nucleic acid amplification test [NAAT], Gimenez staining, and serum antibody titer measurement [ATM]). When the initial test result was negative, 63% of physicians reported not conducting additional tests. Even when they chose to run additional tests, at most 27.8%, 23.6%, 12.3%, and 10.4% of all physicians used NAAT, culture, Gimenez staining, and serum ATM, respectively. The major reasons for not using tests other than UAT were "unavailability in the medical facility," "long turn-around time," and "difficult to collect sputum." CONCLUSIONS: The present survey revealed that most physicians in Japan used UAT alone for diagnosing legionellosis. Eliminating barriers to creating a reasonable environment and edification of physicians are needed to improve the current situation.

Legionella longbeachae pneumonia: A case report and literature review in Japan.

Herein, we report the case of a 74-year-old man diagnosed with Legionella pneumonia detected by Loop-Mediated Isothermal Amplification (LAMP) method, which was suspected to have been transmitted from the potting soil. Legionella longbeachae was identified in the sputum culture. The patient was intubated and maintained on mechanical ventilation. Antimicrobial therapy with azithromycin was also administered. His symptoms were resolved and he was discharged after 26 days of hospitalization. Legionella longbeachae pneumonia rarely occurs in Japan, and published literature of Legionella longbeachae pneumonia cases in Japan was reviewed. Patients with severe pneumonia exposed to potting soils, but with negative urinary antigen test results, should be examined by LAMP method.

Diagnosis and treatment for a case of Legionella longbeachae severe pneumonia and literature review. / 1ä¾‹é•¿æ»©å†›å›¢èŒæ€§é‡ç—‡è‚ºç‚Žè¯Šæ²»åˆ†æžåŠæ–‡çŒ®å¤ä¹ .

As a type of Legionella bacteria, Legionella longbeachae bacteria can lead to very rare legionella disease case in China with clinical characteristics, such as no typical early clinical symptoms, strong toxicity, high mortality, and not easy to detect by conventional etiology. A case of severe pneumonia caused by Legionella longbeachae infection was confirmed by bronchoalveolar lavage fluid pathogen metagenomics, and the patient's condition was improved after targeted anti-infection treatment. At present, our understanding in Legionella longbeachae severe pneumonia is limited. The diagnosis and treatment process of the patient with severe pneumonia of Legionella longbeachaeis retrospectively analyzed and the relevant literature was reviewed to provide the experience for its future diagnosis and treatment.

Diagnosis and Treatment of Adults with Community-acquired Pneumonia. An Official Clinical Practice Guideline of the American Thoracic Society and Infectious Diseases Society of America.

Background: This document provides evidence-based clinical practice guidelines on the management of adult patients with community-acquired pneumonia.Methods: A multidisciplinary panel conducted pragmatic systematic reviews of the relevant research and applied Grading of Recommendations, Assessment, Development, and Evaluation methodology for clinical recommendations.Results: The panel addressed 16 specific areas for recommendations spanning questions of diagnostic testing, determination of site of care, selection of initial empiric antibiotic therapy, and subsequent management decisions. Although some recommendations remain unchanged from the 2007 guideline, the availability of results from new therapeutic trials and epidemiological investigations led to revised recommendations for empiric treatment strategies and additional management decisions.Conclusions: The panel formulated and provided the rationale for recommendations on selected diagnostic and treatment strategies for adult patients with community-acquired pneumonia.

Cutaneous Legionella infections in allogeneic hematopoietic cell transplantation recipients.

To date, only twenty cases of cutaneous legionellosis have been reported. Cutaneous legionellosis has heterogeneous manifestations including abscesses, nodules, and cellulitis. The detection of most cutaneous Legionella species requires specific diagnostic cultures and assays. Herein, we report a case of cutaneous legionella in a hematopoietic cell transplantation recipient with culture-negative nodules unresponsive to empiric antibiotics. We also discuss the varied morphology of cutaneous legionellosis and important diagnostic considerations.

Emerging respiratory infections: The infectious disease pathology of SARS, MERS, pandemic influenza, and Legionella.

Lower respiratory infections remain one of the top global causes of death and the emergence of new diseases continues to be a concern. In the first two decades of the 21st century, we have born witness to the emergence of newly recognized coronaviruses that have rapidly spread around the globe, including severe acute respiratory syndrome virus (SARS) and Middle Eastern respiratory syndrome virus (MERS). We have also experienced the emergence of a novel H1N1 pandemic influenza strain in 2009 that caused substantial morbidity and mortality around the world and has transitioned into a seasonal strain. Although we perhaps most frequently think of viruses when discussing emerging respiratory infections, bacteria have not been left out of the mix, as we have witnessed an increase in the number of infections from Legionella spp. since the organisms' initial discovery in 1976. Here, we explore the basic epidemiology, clinical presentation, histopathology, and clinical laboratory diagnosis of these four pathogens and emphasize themes in humans' evolving relationship with our natural environment that have contributed to the infectious burden. Histology alone is rarely diagnostic for these infections, but has been crucial to bettering our understanding of these diseases. Together, we rely on the diagnostic acumen of pathologists to identify the clinicopathologic features that raise the suspicion of these diseases and lead to the early control of the spread in our populations.

Adaptation of Amoeba Plate Test To Recover Legionella Strains from Clinical Samples.

The isolation of Legionella from respiratory samples is the gold standard for diagnosis of Legionnaires' disease (LD) and enables epidemiological studies and outbreak investigations. The purpose of this work was to adapt and to evaluate the performance of an amoebic coculture procedure (the amoeba plate test [APT]) for the recovery of Legionella strains from respiratory samples, in comparison with axenic culture and liquid-based amoebic coculture (LAC). Axenic culture, LAC, and APT were prospectively performed with 133 respiratory samples from patients with LD. The sensitivities and times to results for the three techniques were compared. Using the three techniques, Legionella strains were isolated in 46.6% (n = 62) of the 133 respiratory samples. The sensitivity of axenic culture was 42.9% (n = 57), that of LAC was 30.1% (n = 40), and that of APT was 36.1% (n = 48). Seven samples were positive by axenic culture only; for those samples, there were <10 colonies in total. Five samples, all sputum samples, were positive by an amoebic procedure only (5/5 samples by APT and 2/5 samples by LAC); all had overgrowth by oropharyngeal flora with axenic culture. The combination of axenic culture with APT yielded a maximal isolation rate (i.e., 46.6%). Overall, the APT significantly reduced the median time for Legionella identification to 4 days, compared with 7 days for LAC (P < 0.0001). The results of this study support the substitution of LAC by APT, which could be implemented as a second-line technique for culture-negative samples and samples with microbial overgrowth, especially sputum samples. The findings provide a logical basis for further studies in both clinical and environmental settings.

Legionella: a reemerging pathogen.

PURPOSE OF REVIEW: The present review summarizes new knowledge about Legionella epidemiology, clinical characteristics, community-associated and hospital-based outbreaks, molecular typing and molecular epidemiology, prevention, and detection in environmental and clinical specimens. RECENT FINDINGS: The incidence of Legionnaire's disease is rising and the mortality rate remains high, particularly for immunocompromised patients. Extracorporeal membrane oxygenation may help support patients with severe respiratory failure. Fluoroquinolones and macrolides appear to be equally efficacious for treating Legionnaires' disease. Whole genome sequencing is an important tool for determining the source for Legionella infections and for understanding routes of transmission and mechanisms by which new pathogenic clones emerge. Real-time quantitative polymerase chain reaction testing of respiratory specimens may improve our ability to diagnose Legionnaire's disease. The frequency of viable but nonculturable organisms is quite high in some water systems but their role in causing clinical disease has not been defined. SUMMARY: Legionellosis remains an important public health threat. To prevent these infections, staff of municipalities and large buildings must implement effective water system management programs that reduce Legionella growth and transmission and all Medicare-certified healthcare facilities must have water management policies. In addition, we need better methods for detecting Legionella in water systems and in clinical specimens to improve prevention strategies and clinical diagnosis.

Legionella feeleii: an unusual organism associated with cutaneous infection in an immunocompromised patient.

We report a 23-year-old immunocompromised woman who, following cardiac transplantation, presented with an unusual cutaneous eruption. She developed a widespread pustular rash, systemic symptoms and a high temperature with raised inflammatory markers. The diagnosis was reached when a skin biopsy was cultured onto Legionella agar (buffered charcoal yeast extract) and Legionella feeleii was isolated. The patient was treated with 6 weeks of moxifloxacin and her cutaneous lesions gradually resolved. Cutaneous Legionella infections are uncommon and usually affect immunocompromised patients.

Presence of Legionella spp. in human dental plaque.

AIMS: The aim of this research is to verify the presence of Legionella in human dental plaque. METHODS: 65 adult patients not treated with systemic or local antibiotics at least 2 months before the time of sample collection were enrolled for plaque collection between September 2015 and December 2016. A brief questionnaire about lifestyle and health risks was administered. Legionella spp. detection has been executed by semi- nested PCR. RESULTS: 8 out of 65 plaque samples (12.3%) were positive for Legionella spp. As regards health risks and lifestyle aspects, no relevant difference was observed between patients involved in our study, except for two positive patients who have reported a COPD ongoing and a pneumonia in the past. CONCLUSIONS: This study represents a step forward in the knowledge of reservoirs of the microorganism and richness of oral microbiota.

Septic arthritis due to Legionella cincinnatiensis: case report and review of the literature.

Legionella spp. are an important cause of pulmonary and rarely extrapulmonary infections. L. cincinnatiensis has only been implicated in five cases to date. We herein report the first case of L. cincinnatiensis septic arthritis in a 90-year old lady with a past medical history of chronic kidney disease. She developed septic arthritis of her left wrist after having received intraarticular corticosteroid injections and oral corticosteroids administered for presumed chondrocalcinosis. Appropriate antimicrobial treatment of L. cincinnatiensis septic arthritis was delayed until identification of this organism in joint biopsies by broad-range bacterial PCR targeting the 16S rRNA gene with subsequent rDNA sequence analysis and by culture on special media. Reviewing all reported cases of septic arthritis caused by Legionella spp. other than L. cincinnatiensis it is notable that diagnosis was established by PCR in the majority of cases and only subsequently confirmed by special culture. Although most patients were immunosuppressed, outcome was favourable. Treatment consisted of a fluoroquinolone alone or in combination with rifampicin or a macrolide. Our case highlights the need for a high index of suspicion for infections with unusual/fastidious organisms when symptoms are suggestive of septic arthritis but conventional methods fail to identify a causative organism.

A gyrB oligonucleotide microarray for the specific detection of pathogenic Legionella and three Legionella pneumophila subsp.

Among the 50 species and 70 serogroups of Legionella identified, Legionella pneumophila, comprising three subsp. (subsp. pneumophila, subsp. fraseri, and subsp. pasculleii), is recognized as the major cause of epidemic legionellosis. Rapid and reliable assays to identify pathogenic Legionella spp., and the three L. pneumophila subsp. in particular, are in great demand. In this study, we analyzed the gyrB genes of eleven Legionella spp. and subsp., comprising L. anisa, L. bozemanii, L. dumoffii, L. feeleii, L. gormanii, L. longbeachae, L. micdadei, L. waltersii, L. pneumophila subsp. pneumophila, L. pneumophila subsp. fraseri, and L. pneumophila subsp. pasculleii. We developed a rapid oligonucleotide microarray detection technique to identify accurately these common pathogenic Legionella spp. and L. pneumophila subsp. To detect multiple Legionella species with high specificity, 31 reproducible probes were designed in the array. Sixty-one strains were analyzed in total, including 37 target pathogens and 24 non-target bacterial species used to validate the microarray. The sensitivity of the detection was 1.0 ng using genomic DNA of three Legionella spp., L. anisa, L. dumoffii, and L. waltersii, or 13 CFU/100 mL using the cultured L. pneumophila subsp. pneumophila. Eight isolated strains were tested using the microarray with 100% accuracy. The data indicated that the technique is an efficient method to diagnose and detect Legionella spp. and subsp. in basic microbiology, clinical diagnosis, epidemiological surveillance, and food safety applications. In addition, a phylogenetic study based on the gyrB gene revealed the genetic relationship among the different Legionella spp. and subsp.

Incorporating Time-Dose-Response into Legionella Outbreak Models.

A novel method was used to incorporate in vivo host-pathogen dynamics into a new robust outbreak model for legionellosis. Dose-response and time-dose-response (TDR) models were generated for Legionella longbeachae exposure to mice via the intratracheal route using a maximum likelihood estimation approach. The best-fit TDR model was then incorporated into two L. pneumophila outbreak models: an outbreak that occurred at a spa in Japan, and one that occurred in a Melbourne aquarium. The best-fit TDR from the murine dosing study was the beta-Poisson with exponential-reciprocal dependency model, which had a minimized deviance of 32.9. This model was tested against other incubation distributions in the Japan outbreak, and performed consistently well, with reported deviances ranging from 32 to 35. In the case of the Melbourne outbreak, the exponential model with exponential dependency was tested against non-time-dependent distributions to explore the performance of the time-dependent model with the lowest number of parameters. This model reported low minimized deviances around 8 for the Weibull, gamma, and lognormal exposure distribution cases. This work shows that the incorporation of a time factor into outbreak distributions provides models with acceptable fits that can provide insight into the in vivo dynamics of the host-pathogen system.

[Legionellosis and its diagnosis]. / Legionelózy a ich diagnostika.

The diagnosis of legionellosis, especially of its severe, life-threatening form, Legionnaires' disease, is complicated, primarily because of non-typical symptoms of the infection, not always dominating atypical pneumonia, and often a very dramatic septic course of the disease with multiorgan failures. The diagnosis of the acute phase of the disease can be established by the detection of Legionella antigen in urine and by PCR/real-time PCR detection of Legionella DNA in serum and lower respiratory tract and urine samples. Cultivation on specific media remains the gold standard, but this very demanding method is rarely used. Serological testing requires paired samples and thus is relevant to the diagnosis at a later stage of infection, although it is to be noted that about 20% of patients do not produce the antibodies. Great progress has been made in typing methods (RFLP, PFGE, or PCR based and sequence based methods) and rapid identification methods (MALDI-TOF).

Legionellosis: a Walk-through to Identification of the Source of Infection.

OBJECTIVES: Although a number of human Legionnaires' disease in tourists are recorded annually in Europe, there are few cases where a direct link can be made between the infected person and the source of infection (hotel or other accommodation). We present a scheme followed in order to track down and identify the source of infection in a tourist suffering from L. pneumophila sg 5 infection, who was accommodated in seven different hotels during his holidays in the island of Crete, and we comment on various difficulties and draw-backs of the process. METHOD: Water samples were collected from the seven hotels where the patient had resided and analyzed at the regional public health laboratory using cultivation and molecular tests. RESULTS: Of 103 water samples analyzed, 19 (18.4%) were positive for Legionella non-pneumophila and 8 (7.8%) were positive for L. pneumophila. A successful L. pneumophila sg 5 match was found between the clinical and environmental sample, which led us to the final identification of the liable hotel. CONCLUSION: Timely notification of the case, within the the European Legionnaires' Disease Surveillance Network (ELDSNet) of the partners involved, is crucial during a course of travel associated with Legionella case investigation. Moreover, the urinary antigen test alone cannot provide sufficient information for the source identification. However, acquiring clinical as well as environmental isolates for serogroup and SBT identification is highly important for the successful matching.

[Legionellosis]. / Légionellose.

Legionellosis refers to the two clinical syndromes caused by Legionella : Pontiac fever, a benign febrile illness and Legionnaires'disease (or pneumonia). Clinically and radiologically, Legionnaires'disease presents itself as a « typical ¼ pneumonia caused by Streptococcus pneumonia. Diagnosis is usually made by using urinary antigen testing. Culture and PCR are also helpful. Legionella is resistant to betalactam antibiotics, and is treated by quinolones or macrolides.

La légionellose regroupe deux entités cliniques : la fièvre de Pontiac, une maladie fébrile bénigne, et la pneumonie à Legionella ou maladie du légionnaire. Sur les plans clinique et radiologique, la pneumonie à Legionella se présente le plus souvent comme une pneumonie « typique ¼ à pneumocoque. Son diagnostic repose généralement sur la mise en évidence d'un antigène de la bactérie dans les urines ; la culture et la PCR sont également des examens utiles. La légionelle est un germe résistant aux bêtalactamines et nécessite un traitement par quinolones ou macrolides.