Bacterial Isolates from Urinary Tract Infection in Dogs in Grenada, and Their Antibiotic Susceptibility

Abstract

Of 52 culture positive urine samples from dogs in Grenada for six years (2004 through 2009) 65.5% of isolates were Gram-negative bacteria, with E. coli as the predominant species, followed by Proteus mirabilis, and Pseudomonas aeruginosa. Other Gram-negative isolates included Klebsiella pneumoniae, Acinetobacter anitratus, and Serratia plymuthica. Among the Gram-positive isolates, Staphylococcus intermedius was the most common species, followed by S. aureus, coagulase-negative staphylococci, and enterococci. Sensitivity results obtained with 6 antibiotics showed least resistance to enrofloxacin, the rate being 19% for all isolates together. More than two-thirds of isolates were resistant to tetracycline. For Gram-positive isolates, resistance to cephalothin was even less than that against enrofloxacin, with a rate of only 13%. Overall resistance to amoxicillin-clavulanic acid was 36%. The most common drug used for treatment of urinary tract infections in Grenada has been amoxicillin-clavulanic acid, followed by enrofloxacin.