Skip to main content
  • ASM
    • Antimicrobial Agents and Chemotherapy
    • Applied and Environmental Microbiology
    • Clinical Microbiology Reviews
    • Clinical and Vaccine Immunology
    • EcoSal Plus
    • Eukaryotic Cell
    • Infection and Immunity
    • Journal of Bacteriology
    • Journal of Clinical Microbiology
    • Journal of Microbiology & Biology Education
    • Journal of Virology
    • mBio
    • Microbiology and Molecular Biology Reviews
    • Microbiology Resource Announcements
    • Microbiology Spectrum
    • Molecular and Cellular Biology
    • mSphere
    • mSystems
  • Log in
  • My alerts
  • My Cart

Main menu

  • Home
  • Articles
    • Current Issue
    • Accepted Manuscripts
    • COVID-19 Special Collection
    • Archive
    • Minireviews
  • For Authors
    • Submit a Manuscript
    • Scope
    • Editorial Policy
    • Submission, Review, & Publication Processes
    • Organization and Format
    • Errata, Author Corrections, Retractions
    • Illustrations and Tables
    • Nomenclature
    • Abbreviations and Conventions
    • Publication Fees
    • Ethics Resources and Policies
  • About the Journal
    • About JCM
    • Editor in Chief
    • Editorial Board
    • For Reviewers
    • For the Media
    • For Librarians
    • For Advertisers
    • Alerts
    • RSS
    • FAQ
  • Subscribe
    • Members
    • Institutions
  • ASM
    • Antimicrobial Agents and Chemotherapy
    • Applied and Environmental Microbiology
    • Clinical Microbiology Reviews
    • Clinical and Vaccine Immunology
    • EcoSal Plus
    • Eukaryotic Cell
    • Infection and Immunity
    • Journal of Bacteriology
    • Journal of Clinical Microbiology
    • Journal of Microbiology & Biology Education
    • Journal of Virology
    • mBio
    • Microbiology and Molecular Biology Reviews
    • Microbiology Resource Announcements
    • Microbiology Spectrum
    • Molecular and Cellular Biology
    • mSphere
    • mSystems

User menu

  • Log in
  • My alerts
  • My Cart

Search

  • Advanced search
Journal of Clinical Microbiology
publisher-logosite-logo

Advanced Search

  • Home
  • Articles
    • Current Issue
    • Accepted Manuscripts
    • COVID-19 Special Collection
    • Archive
    • Minireviews
  • For Authors
    • Submit a Manuscript
    • Scope
    • Editorial Policy
    • Submission, Review, & Publication Processes
    • Organization and Format
    • Errata, Author Corrections, Retractions
    • Illustrations and Tables
    • Nomenclature
    • Abbreviations and Conventions
    • Publication Fees
    • Ethics Resources and Policies
  • About the Journal
    • About JCM
    • Editor in Chief
    • Editorial Board
    • For Reviewers
    • For the Media
    • For Librarians
    • For Advertisers
    • Alerts
    • RSS
    • FAQ
  • Subscribe
    • Members
    • Institutions
CASE REPORTS

Mycotic Aortic Aneurysm Associated with Legionella anisa

Masaki Tanabe, Hiroshi Nakajima, Akiko Nakamura, Takayasu Ito, Mashio Nakamura, Takatsugu Shimono, Hideo Wada, Hideto Shimpo, Tsutomu Nobori, Masaaki Ito
Masaki Tanabe
1Department of Cardiology
  • Find this author on Google Scholar
  • Find this author on PubMed
  • Search for this author on this site
  • For correspondence: m-tanabe@clin.medic.mie-u.ac.jp
Hiroshi Nakajima
1Department of Cardiology
  • Find this author on Google Scholar
  • Find this author on PubMed
  • Search for this author on this site
Akiko Nakamura
2Department of Molecular and Laboratory Medicine
  • Find this author on Google Scholar
  • Find this author on PubMed
  • Search for this author on this site
Takayasu Ito
1Department of Cardiology
  • Find this author on Google Scholar
  • Find this author on PubMed
  • Search for this author on this site
Mashio Nakamura
1Department of Cardiology
  • Find this author on Google Scholar
  • Find this author on PubMed
  • Search for this author on this site
Takatsugu Shimono
3Department of Thoracic and Cardiovascular Surgery, Mie University Graduate School of Medicine, Tsu, Mie, Japan
  • Find this author on Google Scholar
  • Find this author on PubMed
  • Search for this author on this site
Hideo Wada
2Department of Molecular and Laboratory Medicine
  • Find this author on Google Scholar
  • Find this author on PubMed
  • Search for this author on this site
Hideto Shimpo
3Department of Thoracic and Cardiovascular Surgery, Mie University Graduate School of Medicine, Tsu, Mie, Japan
  • Find this author on Google Scholar
  • Find this author on PubMed
  • Search for this author on this site
Tsutomu Nobori
2Department of Molecular and Laboratory Medicine
  • Find this author on Google Scholar
  • Find this author on PubMed
  • Search for this author on this site
Masaaki Ito
1Department of Cardiology
  • Find this author on Google Scholar
  • Find this author on PubMed
  • Search for this author on this site
DOI: 10.1128/JCM.00142-09
  • Article
  • Figures & Data
  • Info & Metrics
  • PDF
Loading

ABSTRACT

Legionella anisa is rarely associated with human disease. Its gene was identified by broad-range PCR in whole blood and excised tissue from a patient with a culture-negative mycotic aneurysm and was considered as a possible pathogen. This case report is potentially useful for the future diagnosis of intravascular infection.

CASE REPORT

The patient was a 79-year-old healthy man with a history of Y-graft replacement for an abdominal aortic aneurysm 3 years ago. Although the postoperative treatment course had been uneventful, he complained of high fever and tenderness of the right inguinal region 1 week before admission. After two sets of blood cultures were drawn, levofloxacin at 200 mg orally (p.o.) every 12 h was prescribed at the outpatient clinic 4 days before admission. However, his condition worsened and he was subsequently admitted to our hospital. Upon admission, his lungs were clear to auscultation and a vascular murmur and tenderness were observed in the right inguinal region. A chest X-ray showed no infiltrate. Laboratory data revealed a leukocyte count of 9,130/mm3 and an elevated C-reactive protein level of 20.1 mg/dl. A BinaxNOW Legionella pneumophila urinary antigen test was negative. Blood samples were cultured with the BacT/Alert 3D blood culture system (bioMérieux) by using both aerobic and anaerobic media (11). Blood cultures collected at the outpatient clinic and upon admission showed negative results. We stopped levofloxacin upon admission and repeated blood cultures 2, 3, and 4 days after cessation of the antibiotic. However, the blood cultures were all negative. Enhanced computed tomography (CT) revealed a pseudoaneurysm at the anastomotic site of the artificial vessel and the right common iliac artery (Fig. 1A), and 67Ga scintigraphy showed abnormal uptake at the same site (Fig. 1B), suggesting a mycotic aortic aneurysm. Vancomycin at 1 g intravenously (i.v.) every day and meropenem at 0.5 g i.v. every 12 h were started empirically for a culture-negative mycotic aneurysm on the fifth day after admission.

FIG. 1.
  • Open in new tab
  • Download powerpoint
FIG. 1.

(A) Enhanced CT upon admission showing a pseudoaneurysm (arrows) at the anastomotic site of the artificial vessel and the right common iliac artery. (B) 67Ga scintigraphy showing abnormal uptake (arrows) at the same site as the pseudoaneurysm.

A broad-range PCR targeting the bacterial 16S rRNA gene, followed by direct sequencing, was performed on whole blood to obtain additional information. Bacterial DNA was extracted by the phenol-chloroform-isoamyl alcohol procedure with a MORA-EXTRA kit (Kyokuto Pharmaceutical, Tokyo, Japan) (9). PCR primers were designed to detect two of the conserved regions of the 16S rRNA gene (Table 1). PCR was performed on a Veriti 96-well thermal cycler (Applied Biosystems, Foster City, CA). DNA was amplified as follows: 10 min at 95°C; 30 cycles of 30 s at 95°C, 30 s at 57°C, and 30 s at 72°C; and finally 10 min at 72°C. Amplified products were sequenced and compared with known bacterial gene sequences by using BLAST (available at the National Center for Biotechnology Information [http://www.ncbi.nih.gov/BLAST/ ]) (13, 16). As a result, Legionella anisa was suspected on the basis of ≥98% BLAST similarity. To confirm this result, we performed an additional assay that targeted Legionella-specific regions within the macrophage inhibitor potentiator (mip) gene (5). DNA was amplified as follows: 10 min at 95°C; 30 cycles of 30 s at 95°C, 30 s at 56°C, and 30 s at 72°C; and finally 10 min at 72°C. The mip gene-based PCR was positive, and L. anisa was identified (Table 1).

View this table:
  • View inline
  • View popup
TABLE 1.

Primer sequences used for broad-range bacterial and Legionella-specific PCRs and sequences of amplified products

Although clarithromycin at 200 mg p.o. every 12 h was added to the i.v. administration of vancomycin and meropenem, subsequent CT demonstrated an increase in the size of the aneurysm. An urgent operation, including resection of the infected aneurysm and replacement of the aortic graft, was performed on the 11th day after admission (Fig. 2). No organisms were identified by Gram staining and Gimenez staining of the excised aortic wall tissue. Cultures performed with blood agar plates with 5% sheep blood and BCYE-agar plates were negative (5). PCRs targeting the 16S rRNA gene and the mip gene were performed with the excised tissue and identified L. anisa again. As the L. anisa gene was detected in both preoperative whole blood and excised tissue, this was considered as a possible pathogen responsible for this mycotic aneurysm. After surgery, linezolid at 600 mg i.v. every 12 h for 2 weeks and pazufloxacin at 500 mg i.v. every 12 h for 3 weeks were administered. The postoperative course was uneventful, and i.v. antibiotics were followed by levofloxacin at 300 mg p.o. every 12 h and clarithromycin at 200 mg p.o. every 12 h.

FIG. 2.
  • Open in new tab
  • Download powerpoint
FIG. 2.

(A) Excised aortic graft attached to the iliac artery and infected aneurysm (dimensions, 2.0 by 2.5 cm). (B) Pathological tissue sample stained with hematoxylin and eosin showing infiltration of inflammatory cells including neutrophils and atherosclerotic change.

Mycotic aortic aneurysms are difficult to treat and are associated with significant mortality. Successful resolution of infected aneurysms depends on early diagnosis, prolonged systemic antibiotic therapy, and timely surgical intervention (8). Intensive antibiotic therapy is crucial for successful treatment. A broad-spectrum antibiotic should be used until culture sensitivity reports are available and a specific antibiotic is determined (12). Therefore, identification of the causative microorganism is important. The organisms most commonly found to be responsible for mycotic aneurysms are Salmonella species and Staphylococcus aureus, but cultures are negative in some cases (8, 12).

Legionella bacteria are small, gram-negative bacilli with fastidious growth requirements. More than 49 different Legionella species have been described, and 20 have been reported to infect humans (6). Although L. pneumophila accounts for most clinical cases, there are some case reports in which L. anisa has been isolated from patients (1, 15). Legionella infections are caused by the inhalation of aerosols generated from water sources contaminated with Legionella bacteria and usually result in pneumonia. Extrapulmonary infections are rare and usually occur as metastatic complications of pneumonia in immunocompromised patients. Although cardiac muscles, the pericardium, and vascular shunts and grafts have been reported as extrapulmonary cardiovascular Legionella infection sites, as far as we know, this is the first case of a mycotic aortic aneurysm associated with L. anisa (6).

The patient had no history of visiting hot springs, and there is no 24-h hot spring bath system in his house, but he has a big pond and a well in his garden. We ordered the testing of water from his garden for the presence of Legionella bacteria by an outside laboratory. No Legionella species was cultured by selective Wadowsky-Yee-Okuda agar medium (10). The source of the L. anisa infection remains unknown.

Diagnostic tests for Legionnaires’ disease include cultures, urine antigen testing (only for L. pneumophila), immunofluorescence microscopy, antibody testing with paired sera, and molecular amplification (6, 7). Although culture tests are the “gold standard” for the diagnosis of Legionnaires’ disease, many clinical laboratories lack the expertise required for testing. In this case, preoperative blood culture and excised tissue cultures, including the use of BCYE-agar plates, were negative. Alternatively, we identified L. anisa gene in his blood and excised tissue by PCR and found it to be the possible pathogen responsible for this patient's mycotic aortic aneurysm. Molecular techniques combined with broad-range PCR amplification and direct sequencing have been useful tools to diagnose culture-negative cases involving pathogens that are difficult to culture or cases involving prior antibiotic treatment (2-4). Our group has applied this technique to culture-negative intravascular infection cases and also reported a case of culture-negative infective endocarditis (14). When using molecular techniques, care must be taken to consider the possibility of false positives due to contamination or transient bacteremia, especially when working with whole-blood samples (4).

We routinely perform PCRs for culture-negative cases, and this is the only case in which the L. anisa 16S rRNA gene was detected. As the L. anisa gene was detected at different times and places in this patient, we believe that the possibility of extraneous contamination is very low. We believe that the L. anisa gene came from the patient's blood and tissue; however, we could not decide whether this organism really caused the patient's mycotic aneurysm or only colonized him because L. anisa is a very low-virulence pathogen.

In conclusion, we encountered a case of mycotic aortic aneurysm with detection of the L. anisa gene by broad-range PCR. This alternative technique may decrease the number of undiagnosed culture-negative cases and may be useful for selecting appropriate antibiotics.

FOOTNOTES

    • Received 23 January 2009.
    • Returned for modification 14 March 2009.
    • Accepted 15 May 2009.
  • Copyright © 2009 American Society for Microbiology

REFERENCES

  1. 1.↵
    Bornstein, N., A. Mercatello, D. Marmet, M. Surgot, Y. Deveaux, and J. Fleurette. 1989. Pleural infection caused by Legionella anisa. J. Clin. Microbiol.27:2100-2101.
    OpenUrlAbstract/FREE Full Text
  2. 2.↵
    Bosshard, P. P., A. Kronenberg, R. Zbinden, C. Ruef, E. C. Böttger, and M. Altwegg. 2003. Etiologic diagnosis of infective endocarditis by broad-range polymerase chain reaction: a 3-year experience. Clin. Infect. Dis.37:167-172.
    OpenUrlCrossRefPubMedWeb of Science
  3. 3.
    Breitkopf, C., D. Hammel, H. H. Scheld, G. Peters, and K. Becker. 2005. Impact of a molecular approach to improve the microbiological diagnosis of infective heart valve endocarditis. Circulation111:1415-1421.
    OpenUrlAbstract/FREE Full Text
  4. 4.↵
    Brouqui, P., and D. Raoult. 2006. New insight into the diagnosis of fastidious bacterial endocarditis. FEMS Immunol. Med. Microbiol.47:1-13.
    OpenUrlCrossRefPubMed
  5. 5.↵
    Diederen, B. M., J. A. Kluytmans, C. M. Vandenbroucke-Grauls, and M. F. Peeters. 2008. Utility of real-time PCR for diagnosis of Legionnaires’ disease in routine clinical practice. J. Clin. Microbiol.46:671-677.
    OpenUrlAbstract/FREE Full Text
  6. 6.↵
    Edelstein, P. H., and N. P. Cianciotto. 2005. Legionella, p. 2711-2724. In G. L. Mandell, J. E. Douglas, and R. Bennett (ed.), Mandell, Douglas, and Bennett's principles and practice of infectious disease, 5th ed. Elsevier, Churchill Livingstone, Philadelphia, PA.
  7. 7.↵
    Fields, B. S., R. F. Benson, and R. E. Besser. 2002. Legionella and Legionnaires’ disease: 25 years of investigation. Clin. Microbiol. Rev.15:506-526.
    OpenUrlAbstract/FREE Full Text
  8. 8.↵
    Hsu, R. B., R. J. Chen, S. S. Wang, and S. H. Chu. 2004. Infected aortic aneurysms: clinical outcome and risk factor analysis. J. Vasc. Surg.40:30-35.
    OpenUrlCrossRefPubMedWeb of Science
  9. 9.↵
    Ichimura, S., M. Nagano, N. Ito, M. Shimojima, T. Egashira, C. Miyamoto, K. Ohkusu, and T. Ezaki. 2007. Evaluation of the invader assay with the BACTEC MGIT 960 system for prompt isolation and identification of mycobacterial species from clinical specimens. J. Clin. Microbiol.45:3316-3322.
    OpenUrlAbstract/FREE Full Text
  10. 10.↵
    Ikedo, M., and E. Yabuuchi. 1986. Ecological studies of Legionella species. I. Viable counts of Legionella pneumophila in cooling tower water. Microbiol. Immunol.30:413-423.
    OpenUrlPubMed
  11. 11.↵
    Kocoglu, M. E., A. Bayram, and I. Balci. 2005. Evaluation of negative results of BacT/Alert 3D automated blood culture system. J. Microbiol.43:257-259.
    OpenUrlPubMedWeb of Science
  12. 12.↵
    Müller, B. T., O. R. Wegener, K. Grabitz, M. Pillny, L. Thomas, and W. Sandmann. 2001. Mycotic aneurysms of the thoracic and abdominal aorta and iliac arteries: experience with anatomic and extra-anatomic repair in 33 cases. J. Vasc. Surg.33:106-113.
    OpenUrlPubMedWeb of Science
  13. 13.↵
    Schabereiter-Gurtner, C., M. Nehr, P. Apfalter, A. Makristathis, M. L. Rotter, and A. M. Hirschl. 2008. Evaluation of a protocol for molecular broad-range diagnosis of culture-negative bacterial infections in clinical routine diagnosis. J. Appl. Microbiol.104:1228-1237.
    OpenUrlCrossRefPubMedWeb of Science
  14. 14.↵
    Takamura, T., M. Tanabe, K. Onishi, S. Yamazato, A. Nakamura, K. Onoda, H. Wada, H. Shimpo, T. Nobori, and M. Ito. 2008. Molecular diagnosis of prosthetic valve endocarditis with aorto-right atrial fistula. Int. J. Cardiol. doi:10.1016/j.ijcard.2008.03.029.
    OpenUrlCrossRef
  15. 15.↵
    Thacker, W. L., R. F. Benson, L. Hawes, W. R. Mayberry, and D. J. Brenner. 1990. Characterization of a Legionella anisa strain isolated from a patient with pneumonia. J. Clin. Microbiol.28:122-123.
    OpenUrlAbstract/FREE Full Text
  16. 16.↵
    Welinder-Olsson, C., L. Dotevall, H. Hogevik, R. Jungnelius, B. Trollfors, M. Wahl, and P. Larsson. 2007. Comparison of broad-range bacterial PCR and culture of cerebrospinal fluid for diagnosis of community-acquired bacterial meningitis. Clin. Microbiol. Infect.13:879-886.
    OpenUrlCrossRefPubMed
View Abstract
PreviousNext
Back to top
Download PDF
Citation Tools
Mycotic Aortic Aneurysm Associated with Legionella anisa
Masaki Tanabe, Hiroshi Nakajima, Akiko Nakamura, Takayasu Ito, Mashio Nakamura, Takatsugu Shimono, Hideo Wada, Hideto Shimpo, Tsutomu Nobori, Masaaki Ito
Journal of Clinical Microbiology Jul 2009, 47 (7) 2340-2343; DOI: 10.1128/JCM.00142-09

Citation Manager Formats

  • BibTeX
  • Bookends
  • EasyBib
  • EndNote (tagged)
  • EndNote 8 (xml)
  • Medlars
  • Mendeley
  • Papers
  • RefWorks Tagged
  • Ref Manager
  • RIS
  • Zotero
Print

Alerts
Sign In to Email Alerts with your Email Address
Email

Thank you for sharing this Journal of Clinical Microbiology article.

NOTE: We request your email address only to inform the recipient that it was you who recommended this article, and that it is not junk mail. We do not retain these email addresses.

Enter multiple addresses on separate lines or separate them with commas.
Mycotic Aortic Aneurysm Associated with Legionella anisa
(Your Name) has forwarded a page to you from Journal of Clinical Microbiology
(Your Name) thought you would be interested in this article in Journal of Clinical Microbiology.
CAPTCHA
This question is for testing whether or not you are a human visitor and to prevent automated spam submissions.
Share
Mycotic Aortic Aneurysm Associated with Legionella anisa
Masaki Tanabe, Hiroshi Nakajima, Akiko Nakamura, Takayasu Ito, Mashio Nakamura, Takatsugu Shimono, Hideo Wada, Hideto Shimpo, Tsutomu Nobori, Masaaki Ito
Journal of Clinical Microbiology Jul 2009, 47 (7) 2340-2343; DOI: 10.1128/JCM.00142-09
del.icio.us logo Digg logo Reddit logo Twitter logo CiteULike logo Facebook logo Google logo Mendeley logo
  • Top
  • Article
    • ABSTRACT
    • CASE REPORT
    • FOOTNOTES
    • REFERENCES
  • Figures & Data
  • Info & Metrics
  • PDF

KEYWORDS

Aneurysm, Infected
Legionella
Legionellosis

Related Articles

Cited By...

About

  • About JCM
  • Editor in Chief
  • Board of Editors
  • Editor Conflicts of Interest
  • For Reviewers
  • For the Media
  • For Librarians
  • For Advertisers
  • Alerts
  • RSS
  • FAQ
  • Permissions
  • Journal Announcements

Authors

  • ASM Author Center
  • Submit a Manuscript
  • Article Types
  • Resources for Clinical Microbiologists
  • Ethics
  • Contact Us

Follow #JClinMicro

@ASMicrobiology

       

ASM Journals

ASM journals are the most prominent publications in the field, delivering up-to-date and authoritative coverage of both basic and clinical microbiology.

About ASM | Contact Us | Press Room

 

ASM is a member of

Scientific Society Publisher Alliance

 

American Society for Microbiology
1752 N St. NW
Washington, DC 20036
Phone: (202) 737-3600

 

Copyright © 2021 American Society for Microbiology | Privacy Policy | Website feedback

Print ISSN: 0095-1137; Online ISSN: 1098-660X