Clinical and microbiologic findings in dogs with bronchoscopically diagnosed tracheal collapse: 37 cases (1990-1995)

Objective-To investigate the role of bacteria in bronchoscopically diagnose d tracheal collapse in dogs by evaluating qualitative results of bacteriolo gic cultures. Design-Retrospective study. Animals-37 dogs with tracheal collapse. Procedure-Clinical records for dogs with tracheal collapse confirmed with b ronchoscopy were reviewed. A protected catheter brush was used to obtain sa mples for bacteriologic culture from the large airways. Results-Results of bacterial culture were negative for 5 of 29 dogs. For 24 dogs, 1 (n = 10), 2 (6), or greater than or equal to 3 (8) species of bact eria were isolated. Pseudomonas spp were isolated most frequently (17/29), and a single Pseudomonas sp grew in 7 samples. Other bacteria included Ente robacter spp (4/29), Citrobacter spp (3/29), and Moraxella, spp, Klebsiella spp, Bordetella, spp, or Acinetobacter spp (2/29 dogs each). Anaerobic and aerobic cultures yielded positive results in samples from 2 dogs. Cytologi c results were available for 13 dogs with positive results of bacteriologic culture; epithelial cells were reported most commonly. Five samples had a small number of neutrophils; bacteria were identified cytologically in 2 of 5 samples that contained neutrophils. Bacteria were also seen in 2 samples that lacked inflammatory cells. Conclusions and Clinical Relevance-Bacteria are commonly isolated from samp les obtained via airway brushing in dogs with tracheal collapse; however, i n the absence of cytologic confirmation of inflammation or infection, an as sociation between bacteria and clinical signs of tracheal collapse cannot b e established.