Objective—To compare clinical efficacy of pulse
administration with itraconazole versus once daily
administration for the treatment of cutaneous and
otic M pachydermatis infection in dogs.
Design—Randomized controlled trial.
Procedure—Dogs were treated with itraconazole orally
(n = 10/group), using a pulse administration regimen (5
mg/kg [2.3 mg/lb], PO, q 24 h for 2 consecutive days per
week for 3 weeks) or once daily administration (5 mg/kg,
PO, q 24 h for 21 days). No other treatment was permitted.
On days 0 and 21, clinical severity of cutaneous
and otic disease was assessed, and samples were collected
for cytologic examination and yeast culture.
Cytology (sum of the mean number of yeast organisms
per oil immersion field for affected sites) and culture
(mean of the score for extent of yeast growth for samples
from affected sites) scores were calculated.
Results—For dogs in both treatment groups, clinical
severity of cutaneous and otic disease was significantly
decreased by day 21, but decrease in severity
was not significantly different between groups.
Similarly, skin cytology, skin culture, and ear culture
scores were significantly decreased on day 21, compared
with day 0, for both groups, but decreases were
not significantly different between groups except that
dogs in the pulse administration group had a significantly
greater decrease in ear culture scores than did
dogs in the daily administration group. However, when
cytology scores only for ear samples were analyzed,
day 21 score was not significantly decreased, compared
with day 0 score, for either group.
Conclusions and Clinical Relevance—Results suggested
that both pulse administration and once daily
administration of itraconazole were efficacious in the
treatment of M pachydermatis cutaneous infection in
dogs. However, adjunctive treatment may be needed
in dogs with M pachydermatis otitis. (J Am Vet Med
Objective—To determine effects of topical antimicrobial
and antimicrobial-corticosteroid preparations on
the ocular flora of horses.
Procedure—One eye was treated 3 times daily for 2
weeks with one of the following ointments: 1) neomycinbacitracin-
polymyxin B, 2) 0.6% prednisolone-0.3% gentamicin,
3) neomycin-polymyxin B-0.05% dexamethasone,
or 4) treated (artificial tears) control. Contralateral eyes of
treated control eyes served as untreated control eyes.
Corneal and conjunctival specimens for bacterial and fungal
cultures were collected prior to initiation of treatment,
after 1 and 2 weeks of treatment, and 2 weeks after concluding
treatment. Changes in culture growth quantity
scores of bacterial and fungal species were analyzed.
Results—The most common species before treatment
were the following: gram-positive bacteria included
Streptomyces spp (66%) , Staphylococcus spp (46%) ,
Bacillus spp (32%) , and Streptococcus spp (32%); gramnegative
bacteria included Moraxella spp (28%) ,
Escherichia coli (24%) , Acinetobacter spp (18%), and
Enterobacter spp (14%); and fungi included Aspergillus
nidulans (56%) , Cladosporium spp (32%), and
Aspergillus fumigatus (22%). In all groups, the percentage
of positive bacterial culture results, growth quantity
score of gram-positive bacteria, and number of bacterial
species isolated decreased at week 1 and increased at
week 2, whereas growth quantity score of gram-negative
bacteria decreased throughout treatment. Differences
were not significant among groups. Fungal growth quantity
score decreased during treatment in all groups.
Repopulation of bacterial and fungal species occurred.
Conclusions and Clinical Relevance—All interventions
decreased the number of microorganisms.
Repopulation of normal flora occurred during and after
treatment. (Am J Vet Res 2005;66:800–811)
Objective—To determine whether staphylococcal isolates cultured from pustules and carriage sites in dogs with superficial bacterial folliculitis were genotypically the same strain by use of pulsed-field gel electrophoresis (PFGE).
Animals—40 dogs with superficial bacterial folliculitis.
Procedures—Samples were obtained from 3 pustules and 3 carriage sites (anus, axillary skin, and nasal mucosa). Bacterial culture, morphologic identification, Gram staining, catalase and coagulase tests, speciation, and PFGE were performed.
Results—Of 246 isolates, 203 were Staphylococcus intermedius, 5 were Staphylococcus aureus, 15 were Staphylococcusspp, and 22 were coagulase-negative staphylococcal isolates. No dog had an isolate with the same PFGE pattern as an isolate from another dog. Coagulase-positive isolates from multiple pustules and multiple carriage sites had the same PFGE pattern in 37 of 39 (94.9%) and 22 of 39 (56.4%) dogs, respectively. Coagulase-positive staphylococcal isolates from at least 1 pustule had the same PFGE pattern as an isolate from at least 1 carriage site in 34 of 36 (94.4%) dogs. Ninety-seven of 116 (83.6%) coagulase-positive staphylococcal isolates from pustules had the same PFGE pattern as an isolate from at least 1 carriage site. Sixty-nine of 91 (75.8%) coagulase-positive staphylococcal isolates from carriage sites had the same PFGE pattern as an isolate from at least 1 pustule.
Conclusions and Clinical Relevance—Coagulasepositive staphylococcal strains were heterogeneous among dogs with superficial bacterial folliculitis. In individual dogs, strains from multiple pustules were genotypically the same, and strains from pustules were genotypically the same as strains from carriage sites.
Objective—To determine whether coagulase-positive staphylococcal isolates that are genotypically the same strain obtained from pustules and carriage sites of individual dogs with superficial bacterial folliculitis have the same antimicrobial susceptibility phenotype.
Animals—40 dogs with superficial bacterial folliculitis.
Procedures—Samples were obtained from 3 pustules and 3 carriage sites (ie, anus, nonlesional axillary skin, and nasal mucosa) for bacterial culture, morphologic identification, Gram staining, catalase and coagulase testing, antimicrobial susceptibility testing, speciation, and pulsed-field gel electrophoresis (PFGE).
Results—223 isolates from pustules and carriage sites were included. Seventeen susceptibility phenotypes were found among isolates. One hundred twenty-eight (100%) isolates from pustules and 95 (100%) isolates from carriage sites were susceptible to cephalothin; 128 (100%) isolates from pustules and 94 (98.9%) isolates from carriage sites were susceptible to amoxicillin-clavulanic acid; 114 (89.1%) isolates from pustules and 82 (86.3%) isolates from carriage sites were susceptible to erythromycin and lincomycin hydrochloride; and 103 (80.5%) isolates from pustules and 70 (73.7%) isolates from carriage sites were susceptible to trimethoprim-sulfamethoxazole. In 37 of 39 (94.9%) dogs, isolates with the same PFGE pattern from multiple pustules had the same susceptibility phenotype. In 21 of 33 (63.6%) dogs, isolates from multiple carriage sites with the same PFGE pattern had the same susceptibility phenotype.
Conclusions and Clinical Relevance—In dogs with superficial bacterial folliculitis, most coagulase-positive staphylococcal isolates from pustules that are genotypically the same strain will have the same susceptibility phenotype and treatment may be based on empiric antimicrobial selection or susceptibility testing of 1 lesional isolate.