Analyze Diet

Rhinosinusitis in an Australian mare caused by Flavodon flavus, a recently recognized invasive fungal pathogen of the horse.

Abstract: We describe herein the clinical, endoscopic, computed tomography (CT), pathologic, and microbiologic features of an infection caused by an under-recognized fungal pathogen, , in a 25-y-old Australian Quarter Horse. The horse had a unilateral obstructive nasal mass, resulting in stertor and dyspnea. On endoscopy, the mass was tan, multinodular, and completely obstructed the nasal passage. CT analysis revealed a large, soft tissue-attenuating and partially mineralized mass in the right nasal passage and dorsal-conchofrontal sinus, expanding into adjacent paranasal sinuses with associated bone lysis and rhinosinusitis. Histopathology of the mass on 2 occasions revealed suppurative inflammation initially, and pyogranulomatous inflammation subsequently. The inflammatory reaction surrounded numerous spherical fungal structures (~60-80 µm diameter) that stained positively on periodic acid-Schiff and Grocott methenamine silver stains. PCR for the fungal internal transcribed spacer 1 and 2 regions followed by Sanger sequencing on a cultured isolate identified the agent as , which has only been reported previously as pathogenic in one horse in the United States, to our knowledge. Previous reports described this fungus as a nonpathogenic, environmental commensal fungus associated with insects and plants.
Publication Date: 2019-12-26 PubMed ID: 31876248PubMed Central: PMC7003237DOI: 10.1177/1040638719897610Google Scholar: Lookup
The Equine Research Bank provides access to a large database of publicly available scientific literature. Inclusion in the Research Bank does not imply endorsement of study methods or findings by Mad Barn.
  • Case Reports
  • Journal Article

Summary

This research summary has been generated with artificial intelligence and may contain errors and omissions. Refer to the original study to confirm details provided. Submit correction.

The research explores a case of rhinosinusitis in a 25-year-old horse caused by a less recognized fungal pathogen, Flavodon flavus. It describes the clinical symptoms, diagnostics used, pathology, and microbiological features of this infection.

Clinical and Endoscopic Features

  • The symptoms of the disease in the horse included a unilateral (one-sided) nasal blockage, which led to noisiness in breathing (stertor) and difficulty in breathing (dyspnea).
  • Using an endoscope, a device used to visualize the internal parts of an animal, the horse was found to have a tan-colored, many-noduled mass that completely blocked the nasal passage.

Computed Tomography and Pathologic Features

  • Using CT scan imaging, the mass was found to consist of soft tissue and partly mineralized portions. It was present in the right nasal passage and also the upper concha-frontal sinus (part of the horse’s complex sinus system).
  • The mass had spread to nearby paranasal sinuses which led to bone lysis (decomposition) and rhinosinusitis, inflammation of nasal and sinus cavities.
  • Pathological tests of the mass at two different times showed initial suppurative inflammation, a condition in which pus forms within tissues, and subsequent pyogranulomatous inflammation, a chronic inflammatory response where mass of immune cells, necrotic debris and fibrous tissue develops.

Microbiologic Features

  • The mass consisted of many spherical fungal cells measuring 60-80 micrometers in diameter which stain positively on periodic acid-Schiff and Grocott methenamine silver stains, both of which are techniques used to visualize fungi.
  • By using Polymerase Chain Reaction (PCR), a molecular technique to amplify DNA, the researchers were able to detect and sequence the internal transcribed spacer regions 1 and 2 from the fungal cells.
  • The fungus was identified as Flavodon flavus using Sanger sequencing on the cultured isolate. This species has previously only been reported to cause disease in one horse in the United States.
  • Flavodon flavus was hitherto known as a nonpathogenic fungus associated with insects and plants. This study, therefore, highlights a novel pathogenic role for this organism.

Cite This Article

APA
Suen WW, Zedler S, Price R, Maguire T, Halliday C, Rosenblatt AJ, Allavena RE, Owen H, Medina-Torres CE. (2019). Rhinosinusitis in an Australian mare caused by Flavodon flavus, a recently recognized invasive fungal pathogen of the horse. J Vet Diagn Invest, 32(1), 162-165. https://doi.org/10.1177/1040638719897610

Publication

ISSN: 1943-4936
NlmUniqueID: 9011490
Country: United States
Language: English
Volume: 32
Issue: 1
Pages: 162-165

Researcher Affiliations

Suen, Willy W
  • School of Veterinary Science, Faculty of Science, The University of Queensland, Gatton, Queensland, Australia (Suen, Zedler, Price, Maguire, Rosenblatt, Allavena, Owen, Medina-Torres).
  • CSIRO Australian Animal Health Laboratory, Geelong, Victoria, Australia (Suen).
  • Centre for Infectious Diseases and Microbiology Laboratory Services, ICPMR, New South Wales Health Pathology, Westmead Hospital, Sydney, New South Wales, Australia (Halliday).
Zedler, Steven
  • School of Veterinary Science, Faculty of Science, The University of Queensland, Gatton, Queensland, Australia (Suen, Zedler, Price, Maguire, Rosenblatt, Allavena, Owen, Medina-Torres).
  • CSIRO Australian Animal Health Laboratory, Geelong, Victoria, Australia (Suen).
  • Centre for Infectious Diseases and Microbiology Laboratory Services, ICPMR, New South Wales Health Pathology, Westmead Hospital, Sydney, New South Wales, Australia (Halliday).
Price, Rochelle
  • School of Veterinary Science, Faculty of Science, The University of Queensland, Gatton, Queensland, Australia (Suen, Zedler, Price, Maguire, Rosenblatt, Allavena, Owen, Medina-Torres).
  • CSIRO Australian Animal Health Laboratory, Geelong, Victoria, Australia (Suen).
  • Centre for Infectious Diseases and Microbiology Laboratory Services, ICPMR, New South Wales Health Pathology, Westmead Hospital, Sydney, New South Wales, Australia (Halliday).
Maguire, Tina
  • School of Veterinary Science, Faculty of Science, The University of Queensland, Gatton, Queensland, Australia (Suen, Zedler, Price, Maguire, Rosenblatt, Allavena, Owen, Medina-Torres).
  • CSIRO Australian Animal Health Laboratory, Geelong, Victoria, Australia (Suen).
  • Centre for Infectious Diseases and Microbiology Laboratory Services, ICPMR, New South Wales Health Pathology, Westmead Hospital, Sydney, New South Wales, Australia (Halliday).
Halliday, Catriona
  • School of Veterinary Science, Faculty of Science, The University of Queensland, Gatton, Queensland, Australia (Suen, Zedler, Price, Maguire, Rosenblatt, Allavena, Owen, Medina-Torres).
  • CSIRO Australian Animal Health Laboratory, Geelong, Victoria, Australia (Suen).
  • Centre for Infectious Diseases and Microbiology Laboratory Services, ICPMR, New South Wales Health Pathology, Westmead Hospital, Sydney, New South Wales, Australia (Halliday).
Rosenblatt, Alana J
  • School of Veterinary Science, Faculty of Science, The University of Queensland, Gatton, Queensland, Australia (Suen, Zedler, Price, Maguire, Rosenblatt, Allavena, Owen, Medina-Torres).
  • CSIRO Australian Animal Health Laboratory, Geelong, Victoria, Australia (Suen).
  • Centre for Infectious Diseases and Microbiology Laboratory Services, ICPMR, New South Wales Health Pathology, Westmead Hospital, Sydney, New South Wales, Australia (Halliday).
Allavena, Rachel E
  • School of Veterinary Science, Faculty of Science, The University of Queensland, Gatton, Queensland, Australia (Suen, Zedler, Price, Maguire, Rosenblatt, Allavena, Owen, Medina-Torres).
  • CSIRO Australian Animal Health Laboratory, Geelong, Victoria, Australia (Suen).
  • Centre for Infectious Diseases and Microbiology Laboratory Services, ICPMR, New South Wales Health Pathology, Westmead Hospital, Sydney, New South Wales, Australia (Halliday).
Owen, Helen
  • School of Veterinary Science, Faculty of Science, The University of Queensland, Gatton, Queensland, Australia (Suen, Zedler, Price, Maguire, Rosenblatt, Allavena, Owen, Medina-Torres).
  • CSIRO Australian Animal Health Laboratory, Geelong, Victoria, Australia (Suen).
  • Centre for Infectious Diseases and Microbiology Laboratory Services, ICPMR, New South Wales Health Pathology, Westmead Hospital, Sydney, New South Wales, Australia (Halliday).
Medina-Torres, Carlos E
  • School of Veterinary Science, Faculty of Science, The University of Queensland, Gatton, Queensland, Australia (Suen, Zedler, Price, Maguire, Rosenblatt, Allavena, Owen, Medina-Torres).
  • CSIRO Australian Animal Health Laboratory, Geelong, Victoria, Australia (Suen).
  • Centre for Infectious Diseases and Microbiology Laboratory Services, ICPMR, New South Wales Health Pathology, Westmead Hospital, Sydney, New South Wales, Australia (Halliday).

MeSH Terms

  • Animals
  • Australia
  • Basidiomycota / isolation & purification
  • Female
  • Horse Diseases / microbiology
  • Horses
  • Humans
  • Male
  • Mycoses / microbiology
  • Mycoses / veterinary
  • Paranasal Sinuses
  • Polymerase Chain Reaction
  • Rhinitis / microbiology
  • Rhinitis / veterinary
  • Sinusitis / microbiology
  • Sinusitis / veterinary
  • Tomography, X-Ray Computed

Conflict of Interest Statement

The authors declared no potential conflicts of interest with respect to the research, authorship, and/or publication of this article.

References

This article includes 20 references
  1. Berrocal A, van den Ingh TS. Pathology of equine phycomycosis.. Vet Q 1987 Apr;9(2):180-4.
    pubmed: 3617421doi: 10.1080/01652176.1987.9694095google scholar: lookup
  2. Brearley JC, McCandlish IA, Sullivan M, Dawson CO. Nasal granuloma caused by Pseudallescheria boydii.. Equine Vet J 1986 Mar;18(2):151-3.
  3. Cruz VC, Sommardahl CS, Chapman EA, Fry MM, Schumacher J. Successful treatment of a sinonasal cryptococcal granuloma in a horse.. J Am Vet Med Assoc 2009 Feb 15;234(4):509-13.
    pubmed: 19222362doi: 10.2460/javma.234.4.509google scholar: lookup
  4. Greet TR. Nasal aspergillosis in three horses.. Vet Rec 1981 Nov 28;109(22):487-9.
    pubmed: 7034361doi: 10.1136/vr.109.22.487google scholar: lookup
  5. Hanselka DV. Equine nasal phyco- mycosis.. Vet Med Small Anim Clin 1977 Feb;72(2):251-3.
    pubmed: 584599
  6. Herr RA, Ajello L, Taylor JW, Arseculeratne SN, Mendoza L. Phylogenetic analysis of Rhinosporidium seeberi's 18S small-subunit ribosomal DNA groups this pathogen among members of the protoctistan Mesomycetozoa clade.. J Clin Microbiol 1999 Sep;37(9):2750-4.
  7. Hodgin EC, Conaway DH, Ortenburger AI. Recurrence of obstructive nasal coccidioidal granuloma in a horse.. J Am Vet Med Assoc 1984 Feb 1;184(3):339-40.
    pubmed: 6698868
  8. Kimura M, Nishimura K, Enoki E, Chikugo T, Maenishi O. Chlamydospores of Rhizopus microsporus var. rhizopodiformis in tissue of pulmonary mucormycosis.. Mycopathologia 2012 Dec;174(5-6):441-50.
    pubmed: 22733079doi: 10.1007/s11046-012-9560-9google scholar: lookup
  9. Kirkland TN, Fierer J. Coccidioides immitis and posadasii; A review of their biology, genomics, pathogenesis, and host immunity.. Virulence 2018;9(1):1426-1435.
  10. Klaiklay S, Rukachaisirikul V, Phongpaichit S, Buatong J, Preedanon S, Sakayaroj J. Flavodonfuran: a new difuranylmethane derivative from the mangrove endophytic fungus Flavodon flavus PSU-MA201.. Nat Prod Res 2013;27(19):1722-6.
    pubmed: 23234367doi: 10.1080/14786419.2012.750315google scholar: lookup
  11. Kozubowski L, Heitman J. Profiling a killer, the development of Cryptococcus neoformans.. FEMS Microbiol Rev 2012 Jan;36(1):78-94.
  12. Lau A, Chen S, Sorrell T, Carter D, Malik R, Martin P, Halliday C. Development and clinical application of a panfungal PCR assay to detect and identify fungal DNA in tissue specimens.. J Clin Microbiol 2007 Feb;45(2):380-5.
    pmc: PMC1829013pubmed: 17122000doi: 10.1128/jcm.01862-06google scholar: lookup
  13. Lin X, Heitman J. Chlamydospore formation during hyphal growth in Cryptococcus neoformans.. Eukaryot Cell 2005 Oct;4(10):1746-54.
  14. More SN, Hernandez O, Castleman WL. Mycotic Rhinitis and Sinusitis in Florida Horses.. Vet Pathol 2019 Jul;56(4):586-598.
    pubmed: 30558508doi: 10.1177/0300985818817046google scholar: lookup
  15. Raghukumar C, D'Souza TM, Thorn RG, Reddy CA. Lignin-modifying enzymes of flavodon flavus, a basidiomycete isolated from a coastal marine environment.. Appl Environ Microbiol 1999 May;65(5):2103-11.
  16. Schaffer-White AB, Harper D, Mayhew M, McKinnon A, Knott L, Allavena RE. Pulmonary adiaspiromycosis in critically endangered northern hairy-nosed wombats (Lasiorhinus krefftii).. Aust Vet J 2017 Nov;95(11):431-436.
    pubmed: 29076222doi: 10.1111/avj.12642google scholar: lookup
  17. Souto EPF, Maia LA, Olinda RG, Galiza GJN, Kommers GD, Miranda-Neto EG, Dantas AFM, Riet-Correa F. Pythiosis in the Nasal Cavity of Horses.. J Comp Pathol 2016 Aug-Oct;155(2-3):126-129.
    pubmed: 27406311doi: 10.1016/j.jcpa.2016.06.005google scholar: lookup
  18. Stewart AJ, Salazar T, Waldridge BM, Schumacher J, Welles EG, Hanson RR, Sartin EA, Lenz SD, Holland M, Beard DM. Multimodal treatment of recurrent sinonasal cryptococcal granulomas in a horse.. J Am Vet Med Assoc 2009 Sep 15;235(6):723-30.
    pubmed: 19751170doi: 10.2460/javma.235.6.723google scholar: lookup
  19. Timoney JF. The pathogenic equine streptococci.. Vet Res 2004 Jul-Aug;35(4):397-409.
    pubmed: 15236673doi: 10.1051/vetres:2004025google scholar: lookup
  20. White TJ. Amplification and direct sequencing of fungal ribosomal RNA genes for phylogenetics. PCR Protocols: A Guide to Methods and Applications 1990:315–322.

Citations

This article has been cited 0 times.