A Blinded Comparison of the Efficacy of Daily and Twice Daily Trimethoprim‐Sulfadiazine and Daily Sulfadimethoxine‐Ormetoprim Therapy in the Treatment of Canine Pyoderma

Abstract

Abstract— In a blinded trial to determine the efficacy of potentiated sulfa drugs in the treatment of canine pyoderma, 50 dogs with superficial pyoderma were randomly assigned to receive either once or twice daily trimethoprim‐sulfadiazine (30mg.kg‐1) or once daily sulfadimethoxine‐ormetoprim (55mg.kg‐1 on the first day, then 27.5 mg.kg‐1 thereafter). Dogs were evaluated prior to antibiotic therapy. Clinical efficacy of the antibiotic was assessed after 3 weeks of antibiotic therapy and, if needed, after 6 weeks of antibiotic therapy. Forty‐five dogs completed the study; 43 dogs were used in the statistical analysis. The percentage of dogs that were cured of their pyoderma with once daily trimethoprim‐sulfadiazine was 38.5% by 3 weeks and 75.9% by 6 weeks. With twice daily trimethoprim‐sulfadiazine, 57.1 and 78.6% of dogs were cured by 3 and 6 weeks, respectively. With once daily sulfadimethoxine‐ormetoprim, 75.0 and 100% of dogs were cured by 3 and 6 weeks, respectively. This difference was not statistically significant, possibly due to the low sample size. Few adverse effects were noted. Résumé— Dans une étude en double aveugle pour apprécier l'efficacité des sulfamides potentialisés dans le traitement des pyodermites canines, cinquante chiens présentant une pyodermite superficielle ont reçu, au hasard, soit deux fois ou une fois par jour du triméthoprime‐sulfadiazine (30 mg.kg‐1) ou une fois par jour du sulfadiméthoxine‐ormétoprime (55mg.kg‐1 le premier jour, puis 27.5 mg.kg‐1). Les chiens ont étéévalués avant le traitement. L'efficacité clinique de l'antibiotique a été appréciée après 3 semaines de traitement et, si besion est, après 6 semaines. Le pourcentage de chiens guéris avec une prise quotidienne de triméthoprime‐sulfadiazine était de 33.5%à 3 semaines et 75.9%à 6 semaines. Avec des prises biquotidiennes de triméthoprime‐sulfadiazine 57.1% et 78.6% des chiens étaint guéris à 3 et 6 semaines. Avec une prise quotidienne de sulfadiméthoxine‐ormétoprime, 75.0% et 100.0% des chiens étaient guéris à 3 et 6 semaines. Cette différence n'était pais statistiquement significative, probablement à cause de la taille trop faible de l'échantilon. Très peu d'effects secondaires ont été notés. Zusammenfassung— Für eine Blindstudie zur Bestimmung der Wirksamkeit von potenzierten Sulfonamidpräparaten bei der Behandlung kaniner Pyrodermie wurden 50 Hunde mit oberflächlicher Pyodermie zufällig ausgewählt, um entweder einmal oder zweimal täglich Trimethoprim‐Sulfadiazin (30mg/kg) oder einmal täglich Sulfadimethoxin‐Ormetoprim zu erhalten (55 mg/kg am ersten Tag, danach 27,5 mg/kg). Die Hunde wurden vor der antibotischen Therapie untersucht. Die klinische Wirksamkeit der Antibiose wurde nach 3 Wochen antibiotischer Therapie und, wenn nötig, nach 6 Wochen antibiotischer Therapie ausgewertet. 45 Hunde durchliefen die Studie vollständig; 43 Hunde fanden in die statistische Analyse Eingang. Der Prozentsatz der Hunde, deren Pyrodermie durch einmal tägliches Trimethoprim‐Sulfadiazin geheilt wurde, lag bei 38,5% nach 3 Wochen und b...

Guidelines for the diagnosis and antimicrobial therapy of canine superficial bacterial folliculitis (AntimicrobialGuidelinesWorkingGroup of theInternationalSociety forCompanionAnimalInfectiousDiseases)

“…Most studies evaluating the efficacy of AMDs indicate that SBF infections are resolved after 3 weeks or more of systemic AMD treatment; rapid improvement over the first 1-2 weeks is typically observed, but resolution of all lesions and prevention of rapid recurrence of disease requires 3-6 weeks of treatment. [17][18][19][20][21][22]28 Although there is no significant difference in the likelihood of resolution of MSSP after 3-4 weeks of systemic AMD treatment compared with MRSP infections, it has been reported that MRSP infections took longer to treat compared with MSSP infections. 60 In a minority of patients, resolution of lesions may be achieved with 2 weeks of systemic AMDs.…”

Sulphonamides: updates on use in veterinary medicine

“…2,5,17,22 SDM/ OMP has been recommended for treatment of a variety of skin infections ranging from skin-fold pyoderma to deep pyoderma with furunculosis. 13,17 A concern with the use of this product in the treatment of deep pyoderma is the risk of adverse side-eects such as keratoconjunctivitis sicca and hypothyroidism when treatment is required beyond 21 days.…”

“…The recommended frequency of administration varies with the type of sulphonamide and the sensitivity of the organism against which the drug is being # 1999 Blackwell Science Ltd, Veterinary Dermatology, 10, 205±215 There is considerable controversy concerning the frequency of administration of SDZ/ TMP and SMX/TMP. 5±7, 13 The veterinary product SDZ/TMP is labelled for once-daily administration in dogs and horses, however many clinicians believe the drug is more ecacious if given twice daily regardless of whether they are using SDZ/TMP or SMX/TMP. 4±7 Once-daily dosing of SDZ/TMP at 30 mg kg 71 orally allows concentrations of trimethoprim to fall below therapeutic levels, but concentrations of sulphadiazine are maintained at levels that are ecacious against sensitive organisms throughout the dosing interval.…”

“…SDM/OMP is moderately expensive, but its excellent ecacy and the convenience of once-daily dosing make it an excellent ®rst-line choice for use in dogs with skin and soft tissue infections. 10,11,13 # 1999 Blackwell Science Ltd, Veterinary Dermatology, 10, 205±215…”

“…7 SMX/OMP has shown excellent clinical ecacy in both super®cial and deep staphylococcal pyoderma. 10,11,13,17 It should be given at the manufacturer's recommendation of 55 mg kg 71 orally on day 1, followed by 27.5 mg kg 71 orally every 24 h. 22 As with the trimethoprim-potentiated sulphonamides, iatrogenic hypothyroidism is a potential complication of therapy extending beyond 21 days. 22 Thyroid function should be monitored in dogs receiving long-term therapy and thyroid replacement therapy may be indicated if SMX/OMP is continued in dogs developing iatrogenic hypothyroidism.…”