Oral Presentation Australian Society for Microbiology Annual Scientific Meeting 2013

A molecular approach to identification of species causing canine sino-nasal aspergillosis (#179)

Jessica J Talbot 1 , Lynelle Johnson 2 , Patricia Martin 1 , Julia Beatty 1 , Deanna Sutton 3 , Catriona Halliday 4 , Justine Gibson 5 , Sarah Kidd 6 , Jörg M Steiner 7 , Beata Ujvari 1 , Vanessa R Barrs 1
  1. Faculty of Veterinary Science, University of Sydney, Camperdown, NSW, Australia
  2. Department of Veterinary Medicine and Epidemiology, University of California, Davis, Davis, California, USA
  3. Department of Pathology , University of Texas Health Science Center at San Antonio School of Medicine, San Antonio, Texas, USA
  4. Centre for Infectious Diseases and Microbiology, Westmead Hospital, Westmead, NSW, Australia
  5. School of Veterinary Science, The University of Queensland, Gatton, QLD, Australia
  6. Mycology Unit, SA Pathology, Women’s and Children’s Hospital, North Adelaide, SA, Australia
  7. Department of Small Animal Clinical Sciences, Texas A&M University, College Station, Texas, USA

Background - Sino-nasal aspergillosis (SNA) is an important cause of chronic nasal disease in dogs. A. fumigatus is the most common aetiological agent based on phenotypic identification. However some Aspergillus spp. can only be reliably identified using molecular methods.
Hypothesis – A. fumigatus is the most common cause of canine SNA.
Animals - Eighty fungal isolates from 79 dogs with previously confirmed SNA, including 53 isolates from the USA (44 from CA; 2 each from FL, MO and NJ; 1 each from MA, TX, and TN) and 27 from Australia (21 from NSW, 6 from QLD). Clinical records of all Australian and Californian cases were available for review.
Methods - Fungal genomic DNA was extracted and sequencing of the ITS1-5.8S-ITS2 ribosomal DNA and partial β-tubulin regions were performed. Species identification was determined using the BLAST algorithm against GenBank and Centraalbureau voor Schimmelcultures databases.
Results – Seventy-eight of 80 isolates were identified as A. fumigatus and 2 from USA as A. tubingensis (Aspergillus section Nigri). Breeds commonly affected were Golden Retriever (13%) and Miniature Schnauzer (10%). There were 39 (75%) male dogs (4 entire, 35 neutered), and 13 (25%) females (2 entire, 11 neutered). The mean and median age at diagnosis was 6 y (range 1-14 y).
Conclusions – A. fumigatus is the most common cause of canine SNA in both Australia and the USA. In contrast to feline SNA there appears to be little heterogeneity in aetiological agents. This is the first report to document a pathogenic role for A. tubingensis in dogs.