OBJECTIVE To evaluate the effect of an immunotherapeutic product on concentrations of anti–Pythium insidiosum antibodies in dogs.
ANIMALS 7 healthy hound-crossbreds.
PROCEDURES Antibody concentrations were evaluated before (day 0) and after administration of the immunotherapeutic product. The immunotherapeutic product was administered on days 0, 7, and 21. Serum was obtained on days 0, 7, 14, 21, 28, 35, 42, 49, and 56. Anti–P insidiosum antibody concentrations were measured and reported as the percentage positivity relative to results for a strongly positive control serum.
RESULTS Mean ± SD percentage positivity before administration of the immunotherapeutic product was 7.45 ± 3.02%. There was no significant change in anti–P insidiosum antibody concentrations after administration of the product, with percentage positivity values in all dogs remaining within the range expected for healthy dogs (3% to 15%).
CONCLUSIONS AND CLINICAL RELEVANCE Administration of the immunotherapeutic product to healthy dogs in accordance with the manufacturer's suggested protocol did not induce a significant change in anti–P insidiosum antibody concentrations. These results suggested that administration of the immunotherapeutic product may not interfere with postadministration serologic monitoring. However, further investigations will be required to determine whether there is a similar effect in naturally infected dogs.
Objective—To evaluate the radial growth assay for use in in vitro susceptibility testing of Pythium insidiosum and a Lagenidium sp and to assess susceptibility of representative isolates to itraconazole, posaconazole, voriconazole, terbinafine, caspofungin, and mefenoxam.
Sample Population—6 isolates each of P insidiosum and Lagenidium sp.
Procedures—Isolates were plated in triplicate onto agar supplemented with antifungal compounds at concentrations of 0.025 to 8 μg/mL. Isolates on dimethyl sulfoxide– and water-supplemented agar served as control samples. Effect of antifungal concentration on colony diameter was assessed with a mixed linear model. Assay variability was assessed with the coefficient of variation.
Results—Colony growth was uniform (mean intra-assay and interassay coefficients of variation were < 5%). Minimal inhibition was evident with voriconazole and posaconazole at 8 μg/mL. Terbinafine at 8 μg/mL significantly reduced growth of P insidiosum and at ≥ 1 μg/mL significantly reduced growth of the Lagenidium sp. Caspofungin and mefenoxam (concentrations ≥ 1 μg/mL and ≥ 0.025 μg/mL, respectively) significantly reduced growth of both pathogens. Mefenoxam at 0.1 μg/mL caused > 50% growth inhibition in 11 of 12 isolates and at 1 μg/mL caused > 90% inhibition in all isolates.
Conclusions and Clinical Relevance—Results suggested that the radial growth assay was a simple, reproducible technique for susceptibility testing of P insidiosum and a Lagenidium sp. Azoles had limited activity, whereas terbinafine and caspofungin caused significant but minimal to moderate inhibition. Only mefenoxam had a profound effect on both pathogens at concentrations likely to be achievable in tissues.
Case Description—A 4-year-old spayed female Boxer was evaluated for a cutaneous mass located on the dorsum. The mass had been present for 6 weeks and was increasing in size.
Clinical Findings—A mass of approximately 10 cm in diameter was detected on the dorsum cranial to the right ilial wing. Histologic examination of a tissue sample from the mass led to the diagnosis of cutaneous pythiosis. Computed tomography of the abdomen and the mass were performed and revealed a contrast-enhancing soft tissue mass of the dorsum and enlarged intra-abdominal lymph nodes.
Treatment and Outcome—The dog underwent surgical excision of the cutaneous mass, including 5-cm skin margins and deep margins of 2 fascial planes. The mass was completely excised on the basis of results of histologic examination of surgical margins. The dog received itraconazole and terbinafine by mouth for 3 months following surgery. Recheck examination at 20 months postoperatively showed no signs of recurrence of pythiosis at the surgical site.
Clinical Relevance—Aggressive surgical excision in combination with medical treatment resulted in a favorable long-term (> 1 year) outcome in this dog. Thorough workup including diagnostic imaging and lymph node evaluation is recommended. If surgery is to be performed, skin margins of 5 cm and deep margins of 2 fascial planes are recommended.
Objective—To determine the pharmacokinetics and safety of voriconazole administered orally in single and multiple doses in Hispaniolan Amazon parrots (Amazona ventralis).
Animals—15 clinically normal adult Hispaniolan Amazon parrots.
Procedures—Single doses of voriconazole (12 or 24 mg/kg) were administered orally to 15 and 12 birds, respectively; plasma voriconazole concentrations were determined at intervals via high-pressure liquid chromatography. In a multiple-dose trial, voriconazole (18 mg/kg) or water was administered orally to 6 and 4 birds, respectively, every 8 hours for 11 days (beginning day 0); trough plasma voriconazole concentrations were evaluated on 3 days. Birds were monitored daily, and clinicopathologic variables were evaluated before and after the trial.
Results—Voriconazole elimination half-life was short (0.70 to 1.25 hours). In the single-dose experiments, higher drug doses yielded proportional increases in the maximum plasma voriconazole concentration (Cmax) and area under the curve (AUC). In the multiple-dose trial, Cmax, AUC, and plasma concentrations at 2 and 4 hours were decreased on day 10, compared with day 0 values; however, there was relatively little change in terminal half-life. With the exception of 1 voriconazole-treated parrot that developed polyuria, adverse effects were not evident.
Conclusions and Clinical Relevance—In Hispaniolan Amazon parrots, oral administration of voriconazole was associated with proportional kinetics following administration of single doses and a decrease in plasma concentration following administration of multiple doses. Oral administration of 18 mg of voriconazole/kg every 8 hours would require adjustment to maintain therapeutic concentrations during long-term treatment. Safety and efficacy of voriconazole treatment in this species require further investigation.
Objective—To assess patterns of seroreactivity to Leptospira serovars in veterinary professional staff and dog owners exposed to dogs with acute leptospirosis and to contrast these patterns in people with those observed in dogs.
Sample Population—Human subjects consisted of 91 people (50 veterinarians, 19 technical staff, 9 administrative personnel, and 13 dog owners) exposed to dogs with leptospirosis. Canine subjects consisted of 52 dogs with naturally occurring leptospirosis admitted to the University of Bern Vetsuisse Faculty Small Animal Clinic in 2007 and 2008.
Procedures—People were tested for seroreactivity to regionally prevalent Leptospira serovars by use of a complement fixation test. A questionnaire designed to identify risk factors associated with seropositivity was used to collect demographic information from each study participant. Dogs were tested for seroreactivity to Leptospira serovars by use of a microscopic agglutination test.
Results—On the basis of microscopic agglutination test results, infected dogs were seropositive for antibodies against Leptospira serovars as follows (in descending order): Bratislava (43/52 [83%]), Australis (43/52 [83%]), Grippotyphosa (18/52 [35%]), Pomona (12/52 [23%]), Autumnalis (6/52 [12%]), Icterohemorrhagiae (4/52 [8%]), Tarassovi (2/52 [4%]), and Canicola (1/52 [2%]). All 91 people were seronegative for antibodies against Leptospira serovars. Therefore, statistical evaluation of risk factors and comparison of patterns of seroreactivity to Leptospira serovars between human and canine subjects were limited to theoretical risks.
Conclusions and Clinical Relevance—Seroreactivity to Leptospira serovars among veterinary staff adhering to standard hygiene protocols and pet owners exposed to dogs with acute leptospirosis was uncommon.