Main topic : Animal Health
Escherichia albertii as a cause of cystitis in a dog - a case report
TRESCH M. 1, THOMANN A. 1, GOHL E. 1, LAMBRIGGER N. 2, KITTL S. 1
1 ZOBA, IVB, University of Bern, Bern, Switzerland; 2 Veterinary Office Cabinet Vétérinaire de Bernex, Bernex, Switzerland
Bacterial cystitis in dogs is most commonly caused by Escherichia coli (1). The genetically very closely related species Escherichia albertii is known as an enteric pathogen in humans as well as a cause of enteritis and septicemia in certain bird species (2, 3). While it has been isolated from feces of healthy dogs, it has not been described as a canine pathogen to date (4). E. albertii is non-motile and occurs in two biogroups: biogroup 1 is indole-negative and lysine-positive while biogroup 2 is indole-positive and lysine-negative and was formerly known as Shigella boydii Serotype 13. Recently, a third biogroup was proposed for strains that are indole-positive and lysine-positive.(5)
Methods and Results
Urine of a 7 year-old male dog was sent for bacterial urinalysis and 10µl were cultured on Trypticase™ Soy II agar with 5% Sheep Blood (TSA-SB) (BD™) and chromAX Urine agar (Axonlab) at 37°C aerobically. After 24 hours incubation, >103 grey, non-hemolytic colonies grew on TSA-SB, which were lactose-negative and appeared colourless on chromAX Urine agar (E. coli is expected to be red). Identification using MALDI-TOF resulted in three species with a score above 2.0: Escherichia coli, Escherichia marmotae and Escherichia albertii. As the isolate was non-motile and MALDI-TOF analysis cannot distinguish between E. coli and Shigella spp., further identification was pursued. The isolate was subjected to 16S rRNA sequencing using universal primers, revealing a 99.5% sequence identity with E. albertii (NR_025569.1). Antibiotic susceptibility testing was performed (AST-GN96, Vitek®2, Biomérieux) and revealed no antibiotic resistance.
This is the first report of E. albertii as a pathogen causing cystitis in a dog, though previous canine infections with this species might have been missed due to misidentification. Shiga toxin-producing strains of this species have been described (3) indicating it may also act as an enteropathogen. Though this isolate was susceptible to all tested antibiotics, it is likely that this species can also acquire the notorious broad range of antibiotic resistances known to occur in E. coli. Further investigation into the occurrence of E. albertii in dogs is needed to assess the risk this species poses to dogs and their owners.