Community Acquired Legionnaire's Disease in a Kidney Transplant Patient.

This case report details the clinical picture of a renal transplant recipient infected with community acquired Legionella pneumonia. While it is more commonly associated as a nosocomial infection due to pathogenic organisms in a hospital's water supply, this case serves as a reminder to consider the patient's impaired cellular immune function when trying to diagnose community acquired pneumonia.

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.

Urine antigen tests for the diagnosis of respiratory infections: legionellosis, histoplasmosis, pneumococcal pneumonia.

Urinary antigen testing has grown in popularity for several significant respiratory infections, particularly Legionella pneumophila, Streptococcus pneumoniae, and Histoplasma capsulatum. By capitalizing on the concentration of shed antigen from a variety of pathogens in the kidneys for excretion in the urine, urinary antigen testing can be used to obtain rapid test results related to respiratory infection, independent of an invasive collection such as a bronchoalveolar lavage. This article describes the 3 aforementioned organisms, their role in respiratory disease, and the current status of urinary antigen testing in their respective diagnosis.

[Comparison and evaluation of the Binax EIA and Biotest EIA urinary antigen kits for detection of Legionella pneumophila antigen in urine samples]. / Ocena przydatnosci komercyjnych testów immunoenzymatycznych biotest EIA i Binax EIA do wykrywania antygenu Legionella pneumophila w próbkach moczu osób z legioneloza.

The Binax and the Biotest urinary antigen kits for detection of L. pneumophila antigen were compared by testing of selected 67 urine samples obtained from EWGLI as reference samples in External Quality Assessment Scheme. Thirty nine were positive with the Binax kit (100% of sensitivity), and 33 were positive with the Biotest (84.6% of sensitivity). The test specificities were 100% for the both kits. It was concluded that the Binax kit was more suitable for the routine diagnosis of Legionella infections than the Biotest kit.

Severe non-type-1 Legionella pneumophila infection without pneumonia.

We present a patient with myalgia and ongoing fever without respiratory symptoms caused by a Legionella pneumophilia infection. We conclude that in patients with fever of unknown origin legionellosis should be considered, even in the absence of pulmonary symptoms. When considering legionellosis, diagnostic tests should include the urinary antigen test.

Systematic review and metaanalysis: urinary antigen tests for Legionellosis.

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.

Changes in prevention and outbreak management of Legionnaires disease in the Netherlands between two large outbreaks in 1999 and 2006.

We describe an outbreak of Legionnaires' disease in 2006 in Amsterdam, the Netherlands. Comparisons with the outbreak that took place in 1999 are made to evaluate changes in legionella prevention and outbreak management. The 2006 outbreak was caused by a wet cooling tower. Thirty-one patients were reported. The outbreak was detected two days after the first patient was admitted to hospital, and the source was eliminated five days later. The 1999 outbreak was caused by a whirlpool at a flower show, and 188 patients were reported. This outbreak was detected 14 days after the first patient was admitted to hospital, and two days later the source was traced. Since 1999, the awareness of legionellosis among physicians, the availability of a urinary antigen tests and more efficient early warning and communication systems improved the efficiency of legionellosis outbreak management. For prevention, extensive legislation with clear responsibilities has been put in place. For wet cooling towers, however, legislation regarding responsibility and supervision of maintenance needs to be improved.

[Serologic diagnostics of Legionella infection].

Technical approaches to construction of preparations for serologic diagnostics of Legionella infection were presented in the article; antigenic- and immunoglobulin-based diagnostic kits with known characteristics were developed. Immunogenic properties of protein and lypopolysaccharide antigens, which have diagnostic value, were studied; similarity of protein antigens from 7 serogroups of L. pneumophila was demonstrated. Soluble antigen with known composition was obtained and used for the development of antigen-based polymeric kit for diagnostics of Legionella infection. On the basis of hyperimmune sera, immunoglobulin-based polymeric diagnostic kit and array of coagglutinating diagnostic kits for the mentioned 7 serogroups were developed. Antigen-based polymeric diagnostic kit was recommended for licensure.

[Diagnostic role of different immunologic methods for laboratory diagnostics of legionellosis].

The aim of the study was a comparative analysis of diagnostic value of different laboratoty methods conducted on the basis of results of examination of patients during Legionnaires' disease outbreak in town Verkhnyaya Pyshma. Retrospective analysis of laboratory data from 74 patients with diagnosis of Legionnaires' disease was performed. Complex of laboratory methods was used (polymerase chain reaction (PCR), enzyme immunoassay (EIA), immunochromatography). In group of patients with Legionnaires' disease, the highest proportion of positive results (73%) was obtained by the EIA determining total specific antibodies in urine. Determination of antigen in urine by immunochromatographic express-test yielded 52% of positive results. PCR testing of blood specimens yielded positive results in 65% of samples but was low specific, due to that in 19% of patients from control group false-positive results were obtained. Testing of 3 autopsy samples showed that all specimens contained DNA of the causative agent. Performed analysis allowed to recommend complex use of immunochromatographic express-test of antigen detection and identification of total specific antibodies by EIA during mass people examination.

Impact of rapid urine antigen tests to determine the etiology of community-acquired pneumonia in adults.

STUDY OBJECTIVES: To evaluate the rapid urine antigen tests, including a new rapid immunochromatographic test (ICT) for the detection of the Streptococcus pneumoniae antigen and an enzyme immunoassay (EIA) for the detection of the Legionella antigen, in order to improve the diagnosis of community-acquired pneumonia (CAP) in adults. DESIGN: Prospective study. SETTING: A tertiary hospital in Spain. PATIENTS: We consecutively recruited 107 adults with CAP evaluated at our hospital. INTERVENTIONS: The analyses included blood and sputum cultures, pleural fluid culture (if present) and serologic studies. The detection of the Legionella pneumophila urinary antigen was performed by EIA, and the detection of S. pneumoniae antigen in urine samples was performed by counterimmunoelectrophoresis (CIE) and a rapid ICT. RESULTS: Using conventional microbiologic tests we succeeded in performing the etiologic diagnosis of 39 out of the 107 cases (36.4%). The inclusion of rapid antigen detection techniques increased the percentage of diagnosis to 54.2%, which represents a total increase of 17.8% (P=0.034). CONCLUSIONS: The data obtained in this study indicate that rapid urine antigen tests are very useful to determine CAP etiology in adults and, consequently, to quickly identify a group of patients in whom narrow spectrum antibiotics may be used.

Comparison of three Legionella urinary antigen assays during an outbreak of legionellosis in Belgium.

During an outbreak of legionellosis in Belgium, urine samples of 32 legionellosis patients were tested with three Legionella urinary antigen assays: the Biotest enzyme immunoassay (EIA) kit, the Binax EIA kit and the Binax NOW Immunochromatographic Test kit. The three tests were concomitantly compared. The test sensitivities on the first urine samples were 65.6 % for the Biotest EIA, 50.0 % for the Binax EIA and 56.3 % for the Binax NOW. Testing of a second urine sample increased the sensitivities to 71.9 %, 59.4 % and 65.6 %, respectively. The differences were not statistically significant. In outbreak settings, testing second samples from patients presenting with symptoms but initially testing negative and/or concentrating urine samples for testing might be valuable additions to the urinary antigen test to increase the sensitivities of the tests.

[Epidemiological monitoring of legionellosis: a case-control study in an university general hospital]. / La sorveglianza epidemiologica della Legionellosi in un Policlinico Universitario: risultati di un anno di attività.

The authors report the early results of a case-control study carried out about the risk of legionellosis. During the first year, they have tested urine samples from patients with unknown pneumonia, using a legionella-sensitive test for the detection of its antigen. Out of 171 samples, 9 have turned out to be positive (5.3%). Lifestyles, predisposing factors, possible sources of infection and stressful events were investigated.

Comparison of the Binax Legionella urinary antigen enzyme immunoassay (EIA) with the Biotest Legionella Urin antigen EIA for detection of Legionella antigen in both concentrated and nonconcentrated urine samples.

We evaluated a newly commercial enzyme immunoassay (EIA) (Biotest Legionella Urin Antigen EIA; Biotest AG, Dreieich, Germany) for detection of antigens of all Legionella pneumophila serogroups with a relatively wide spectrum of cross-reactivity as well as antigens of other Legionella spp. by comparing its sensitivity and specificity with those of an EIA for detection of L. pneumophila serogroup 1 antigen (Legionella urinary antigen EIA; Binax, Portland, Maine). Both tests were performed with both concentrated and nonconcentrated urine samples. We also evaluated the capabilities of both EIAs to detect extracted soluble antigens of American Type Culture Collection (ATCC) Legionella strains (L. pneumophila serogroups 1 to 14, L. bozemanii, and L. longbeachae). The sensitivity of the Biotest EIA was 66.66% in nonconcentrated urine and 86.66% in concentrated urine. The sensitivity of the Binax EIA was 63.76% and 88.88% in nonconcentrated and concentrated urine, respectively. The specificity was 100% in nonconcentrated and concentrated urine for both assays. The Binax EIA and Biotest EIA detected extracted soluble antigens of L. pneumophila serogroups 1 to 14 and L. bozemanii ATCC strains. The cross-reactions observed with the Binax EIA were probably due to common epitopes directly related to lipopolysaccharide. Further studies are required to determine the usefulness of the Binax EIA for detection of urinary antigens from Legionella species and serogroups other than L. pneumophila serogroup 1. The Biotest EIA proved to be as rapid, sensitive, and specific as the Binax EIA for the diagnosis of legionellosis. Concentration of antigen present in urine increased the sensitivities of both techniques with no reduction in specificity.

Legionella urinary antigen testing: potential impact on diagnosis and antibiotic therapy.

Although Legionella is an important cause of severe pneumonia, difficulty still exists in its diagnosis. Because at least 80% of patients with legionellosis excrete the Legionella antigen in their urine, various methods have been investigated for urinary antigen detection. Specificity for these methods has been reported to be 100%, and sensitivity has been shown to vary between 70 and 100%. The advantages of these methods include ease of specimen collection, the ability to obtain large quantities of specimen for concentration, the ability to detect antigen after initiation of antibiotic therapy, and the ability to obtain results quickly. Disadvantages include the ability to only reliably detect urinary L. penumophila serogroup 1 antigen and the inability to diagnose relapse or reinfection due to persistence of antigen excretion. Of the commercially-available detection methods, the polyclonal enzyme-linked immunosorbent assay (ELISA) appears to be most efficient. Its use with routine Legionella screening procedures should be considered in target populations, with the intent of early diagnosis and antibiotic therapy streamlining.

Broad-spectrum enzyme-linked immunosorbent assay for detection of Legionella soluble antigens.

An enzyme-linked immunosorbent assay (ELISA) was developed which detected soluble antigens from culture extracts of Legionella pneumophila serogroups 1 to 8, L. micdadei, L. bozemanii serogroups 1 and 2, L. dumoffii, L. gormanii, L. longbeachae serogroups 1 and 2, L. wadsworthii, L. oakridgensis, L. anisa, L. feeleii serogroup 1, and L. jordanis. The assay was approximately 10-fold more sensitive for the eight L. pneumophila serogroups than for the other Legionella species tested. The ELISA detected Legionella antigens in the urine specimens of 25 of 35 patients with L. pneumophila serogroup 1, 3, 4, 6, and 8; L. micdadei; and L. longbeachae serogroup 1 infections. None of the 334 urine specimens from patients with either non-Legionella pneumonia or urinary tract infections was positive. For 10 patients from whom sequential urine specimens were available, Legionella antigens were not detectable from 7 to 19 days after laboratory diagnosis. Test sensitivity was not affected by heavy bacterial contamination. This ELISA offers the detection of a broad spectrum of Legionella antigens by a single test.