Feline sporotrichosis: a case series of itraconazole-resistant Sporothrix brasiliensis infection.

The treatment of feline sporotrichosis is a challenge for veterinary clinicians since refractory cases may occur, due either to patient and/or to pharmacological management errors or due to the development of antifungal resistance. Thus, we aimed to describe the therapeutic history of feline cases infected by itraconazole-resistant Sporothrix brasiliensis in an endemic region of Southern Brazil. Medical records of cats attended at the Veterinary Clinic Hospital (Pelotas/RS, Brazil) between 2016 and 2017 were reviewed. Twelve cases of infection by S. brasiliensis with that showed high minimum inhibitory concentration (MIC) values (≥ 4 µg/mL) to itraconazole by M38-A2 of CLSI were selected. At the hospital consultation, disseminated (cats 1-l0, 12) and localized (cat 11) skin lesions remained in the cats, even after treatment with fluconazole, ketoconazole (02/12), and itraconazole (ITZ, 09/12) performed before this study. High doses (25-100 mg/kg/day) of ITZ for up to 4 months (03/12, cats 2, 6, 12) or over 12 months (05/12, cats 1, 5, 7, 8, 11) did not provide a clinical cure, except for the association of ITZ plus potassium iodide (01/12, cat 12) for 3 months, which proved useful in infections with itraconazole-resistant S. brasiliensis. However, the combined issues of abandonment of therapy by owners for financial reasons, difficulties surrounding therapy administration (03/12, cats 6, 11, 12), and the inappropriate choice of medication (01/12, cat 6), together reflect the reality of this endemic region, which greatly compromises clinical healing. This study highlighted the occurrence of refractory cases by itraconazole-resistant S. brasiliensis in cats from Southern Brazil, as well as the abandonment of treatment and therapeutic errors. We warn of the need for antifungal susceptibility tests to adapt therapeutic protocols in feline sporotrichosis.

Sporotrichosis caused by Sporothrix brasiliensis in Argentina: Case report, molecular identification and in vitro susceptibility pattern to antifungal drugs.

Sporotrichosis is considered a neglected disease of humans and animals in many regions of the world and is the most frequent implantation mycosis in Latin America. OBJECTIVES: To illustrate the zoonotic importance of the disease, describing a case involving a veterinarian and an infant that acquired the disease from a domestic cat and to describe, genotype and characterize these new isolates. METHODS: Direct examination of tissue samples from the two patients and feline lesions revealed the presence of Sporothrix yeast-like organisms. Fungal cultures and molecular identification of the strains were performed. Since antifungal susceptibility data of animal-borne isolates are scarce, the in vitro susceptibility testing by a microdilution reference method was determined against azoles, amphotericin B and terbinafine. RESULTS: Fungal culture and sequence analysis of the ITS region of rDNA and calmodulin and ß-tubulin genes confirmed the diagnosis and the causative agent as Sporothrix brasiliensis. In all cases, terbinafine was the most active drug, followed by posaconazole, itraconazole and voriconazole; the least active drugs were amphotericine B and fluconazole. Lack of clinical response in the veterinarian and in the infant to itraconazole and potassium iodide, respectively was observed. CONCLUSIONS: This study contributed to the molecular epidemiology of Sporothrix species in Argentina and the characterization of the in vitro susceptibility pattern of S. brasiliensis isolates recovered from a cat and two humans involved in this case of zoonotic sporotrichosis. Bearing in mind the "One Health" concept, the experience described in the present study highlights the need for future strategies for sporotrichosis treatment, control and prevention.

Usage patterns of carbapenem antimicrobials in dogs and cats at a veterinary tertiary care hospital.

BACKGROUND: Carbapenems are a class of antimicrobials reserved for resistant infections or systemically ill people, yet the extent and context in which they are prescribed in the small animals is understudied. HYPOTHESIS/OBJECTIVE: To describe cases in dogs and cats treated with carbapenems to establish baseline data regarding the types of infections, outcomes, and resistance profiles of target infections. We hypothesize that prescribing practices for carbapenems at a veterinary tertiary care hospital would not comply with the recommended use guidelines in human medicine. METHODS: Retrospective study of veterinary medical records from all dogs and cats prescribed carbapenems between May 1, 2016, and April 30, 2017. RESULTS: A total of 81 infections (71 in dogs and 10 in cats) representing 68 animals (58 dogs and 10 cats) involving carbapenem use were identified. Cultures were performed in 65/81 (80%) infections, and antimicrobial use was de-escalated or discontinued in 10/81 (12%) infections. The average duration of treatment was 27.5 days and ranged from 1 to 196 days. Resistance to more than 3 antimicrobial classes was present in 57/115 (50%) isolates. Resistance to carbapenems was found in 2/64 (3%) of the bacterial isolates with reported carbapenem susceptibility. CONCLUSIONS AND CLINICAL IMPORTANCE: The majority of carbapenem use at a veterinary tertiary care hospital was prescribed in conjunction with culture and sensitivity determination, with de-escalation performed in a minority of cases, and treatment durations longer than typically recommended in human medicine.

Zoonotic multidrug-resistant microorganisms among small companion animals in Germany.

Antimicrobial multidrug-resistant microorganisms (MDRO) can be transmitted between companion animals and their human owners. Aim of this study was to determine the prevalence of extended spectrum beta-lactamase-producing Enterobacteriaceae (ESBL-E) and Staphylococcus aureus including methicillin-resistant S. aureus (MRSA) in different companion animal species. Dogs (n = 192), cats (n = 74), and rabbits (n = 17), treated in a veterinary practice and hospital or living in an animal shelter and private households, were sampled. All facilities were located in a region characterized by a high density of pig production. Nasal, buccal and perianal swabs were enriched and cultured on solid chromogenic selective media. A subgroup of 20 animals (13 dogs, 3 cats, 4 rabbits) was analyzed for the presence of staphylococci other than S. aureus. Amongst all animals (n = 283), twenty dogs (10.4%) and six cats (8.1%) carried S. aureus. MRSA was found in five dogs (2.6%) and two cats (2.7%). Isolates were of spa types t011, t034, t108 (all mecA-positive, ST398), and t843 (mecC-positive, ST130), typical for livestock-associated (LA)-MRSA. Except for one dog, MRSA-positive animals did not have direct contact to husbandry. ESBL-Escherichia coli (blaCTX-M/blaTEM/blaSHV genes) were present in seven dogs (3.6%), one cat (1.4%) possessed a cefotaxime-resistant Citrobacter freundii isolate (blaTEM/blaCMY-2 genes). MDRO carriage was associated with animals from veterinary medical settings (p<0.05). One dog and one rabbit carried methicillin-resistant coagulase-negative staphylococci. The exclusive occurrence of MRSA lineages typically described for livestock stresses the impact of MDRO strain dissemination across species barriers in regional settings. Presence of ESBL-E and LA-MRSA among pets and probable dissemination in clinical settings support the necessity of a "One Health" approach to address the potential threats due to MDRO-carrying companion animals.

In vitro efficacy of povidone iodine and hydroxyethyl cellulose, alone and in combination, against common feline ocular pathogens.

Infectious ocular disease, such as conjunctivitis, is common in cats and can be caused by several viruses and bacteria, either as a single infection or as co-infections. In this study, povidone-iodine (PVP-I), alone or compounded with hydroxyethyl cellulose (HEC), was investigated for its efficacy against these pathogens in vitro. Whilst PVP-I alone was effective at inhibiting feline herpesvirus type 1 (FHV-1), Chlamydia felis, and Mycoplasma felis, PVP-I with HEC exerted a synergistic inhibitory effect against FHV-1 and C. felis. In contrast, only minimal inhibition of feline calicivirus was observed. These results demonstrate that PVP-I, alone and in combination with HEC, is effective against some feline ocular pathogens when tested in cell lines in vitro. In vivo studies investigating the systemic safety, ocular tolerance, and clinical efficacy of this combination in cats would be necessary before it could be recommended as a therapy in affected cats.

Antimicrobial resistance in bacteria isolated from cats and dogs from the Atlantic Provinces, Canada from 1994-2013.

Antimicrobial susceptibility patterns and trends in bacteria isolated from cats and dogs were determined from diagnostic laboratory data from the Atlantic Veterinary College Diagnostic Services Bacteriology Laboratory over a 20-year period. Clinical samples were most commonly from the urinary tract and the ear. Staphylococcus spp. and Escherichia coli were the bacteria that were most frequently isolated. Increases in percentage resistant were seen with E. coli to cephalexin (57% to 61%), Pasteurella spp. to erythromycin (35% to 53%), and Pseudomonas aeruginosa (31% to 39%), and Streptococcus spp. (46% to 53%) to enrofloxacin. The frequency of resistance did not change significantly over the study period; however, increased enrofloxacin resistance was identified for canine isolates of Staphylococcus spp., Streptococcus spp., Enterococcus spp., E. coli, P. aeruginosa, and Proteus spp. Multidrug resistance was observed in 12% and 9% of the isolates from dogs and cats, respectively. Data from this study could be used to guide empirical antimicrobial selection in companion animal veterinary practices in Atlantic Canada.

Résistance antimicrobienne des bactéries isolées chez des chats et des chiens des provinces de l'Atlantique, Canada, de 1994 à 2013. Les tendances de susceptibilité antimicrobienne des bactéries isolées chez des chats et des chiens ont été déterminées d'après les données des laboratoires de diagnostic du Diagnostic Services Bacteriology Laboratory de l'Atlantic Veterinary College pendant une période de 20 ans. Les échantillons cliniques provenaient le plus communément des voies urinaires et de l'oreille. Staphylococcus spp. et Escherichia coli étaient les bactéries les plus fréquemment isolées. Une hausse du pourcentage de la résistance a été observée pour E. coli à la céphalexine (de 57 % à 61 %), pour Pasteurella spp. à l'érythromycine (de 35 % à 53 %) ainsi que pour Pseudomonas aeruginosa (de 31 % à 39 %) et Streptococcus spp. (de 46 % à 53 %) à l'enrofloxacine. La fréquence de la résistance n'a pas changé significativement pendant la période de l'étude. Cependant, une résistance accrue à l'enrofloxacine a été identifiée pour les isolats canins de Staphylococcus spp., de Streptococcus spp., d'Enterococcus spp., d'E. coli, de P. aeruginosa, et de Proteus spp. La multirésistance aux médicaments a été observée dans 12 % et 9 % des isolats des chiens et des chats, respectivement. Les données de cette étude pourraient être utilisées pour guider le choix empirique des antimicrobiens dans les pratiques vétérinaires pour animaux de compagnie des provinces de l'Atlantique.(Traduit par Isabelle Vallières).

Antimicrobial susceptibility survey on bacterial agents of canine and feline urinary tract infections: Weight of the empirical treatment.

OBJECTIVES: This work characterised the antimicrobial susceptibility of uropathogens isolated from empirically treated dogs and cats. Within-household transmission of uropathogens can involve humans and companion animals. Knowledge on the prevalence and susceptibility pattern of isolates from canine and feline urine samples and the impact of prior antimicrobial treatment is important to prevent the dissemination of antimicrobial resistance. METHODS: A retrospective study was conducted selecting antibiotic-treated companion animals. Urine samples were collected by cystocentesis and were submitted to an Italian diagnostic laboratory over a 2-year period (2013-2015). The antimicrobial susceptibility of the isolates was analysed both using Clinical and Laboratory Standards Institute (CLSI) guidelines and a formula to help select rational antimicrobial therapy. RESULTS: Gram-negative bacteria were clearly prevalent. Gentamicin had the highest impact factors. Amoxicillin/clavulanic acid and doxycycline appeared to be the most effective compounds against Gram-positive infections, whilst marbofloxacin may be a useful option against Gram-negative urinary tract infections (UTIs) as well as doxycycline and trimethoprim/sulfamethoxazole in cats and dogs, respectively. Consulting published studies, a comparable overall trend regarding bacterial species incriminated in canine and feline UTIs and their susceptibilities seems likely, despite different circumstances where the studies were conducted. CONCLUSIONS: Companion animals are potential reservoirs of drug-resistant uropathogens. Judicious use of antibiotics is necessary to maintain the efficacy of antimicrobials in human and veterinary medicine. Antimicrobial susceptibility monitoring programmes are therefore essential to facilitate the choice of antimicrobial agent that is most likely to be effective, particularly in cases of prior antimicrobial treatment.

Septic keratitis in dogs, cats, and horses in Switzerland: associated bacteria and antibiotic susceptibility.

OBJECTIVE: To evaluate the most common bacterial pathogens associated with septic keratitis in veterinary patients from Switzerland. The second objective was to analyze antibiotic susceptibility test results of the identified bacterial pathogens. The third objective was to evaluate potential breed predispositions to septic keratitis. PROCEDURES: Two hundred and fifty-five cultures and antibiotic susceptibility reports from dogs, cats, and horses with septic keratitis that were presented to the University of Zurich Veterinary Medical Teaching Hospital between 2009 and 2013 were reviewed. Odds ratios for the risk of having a septic keratitis were estimated for all dog and cat breeds compared to the general nonbrachycephalic hospital population. RESULTS: Ninety-six, 29, and 31 positive cultures were obtained from 89 canine, 28 feline, and 29 equine eyes, respectively. Repeat sampling accounted for the differences in numbers. Negative culture results were obtained in 50, 31, and 18 cases. Staphylococci and streptococci accounted for 66% of the isolates in dogs and 80% of the isolates in cats and horses. Staphylococcus spp. had a higher percentage of fluoroquinolone-resistant isolates compared to previous reports. Brachycephalic breeds had elevated odds ratios for the presence of septic keratitis. CONCLUSION: Identified bacterial pathogens and their prevalence as well as the elevated odds ratios for septic keratitis in brachycephalics are roughly consistent with previous studies. Based on systemic breakpoint data, resistance to commonly used topical antibiotics, including the second-generation fluoroquinolones, was found.

Phytochemical-rich foods inhibit the growth of pathogenic trichomonads.

BACKGROUND: Plants produce secondary metabolites that often possess widespread bioactivity, and are then known as phytochemicals. We previously determined that several phytochemical-rich food-derived preparations were active against pathogenic foodborne bacteria. Trichomonads produce disease (trichomoniasis) in humans and in certain animals. Trichomonads are increasingly becoming resistant to conventional modes of treatment. It is of interest to test bioactive, natural compounds for efficacy against these pathogens. METHODS: Using a cell assay, black tea, green tea, grape, pomegranate, and jujube extracts, as well as whole dried jujube were tested against three trichomonads: Trichomonas vaginalis strain G3 (found in humans), Tritrichomonas foetus strain D1 (found in cattle), and Tritrichomonas foetus-like organism strain C1 (found in cats). The most effective of the test substances was subsequently tested against two metronidazole-resistant Trichomonas vaginalis strains, and on normal mucosal flora. RESULTS: Black tea extract inhibited all the tested trichomonads, but was most effective against the T. vaginalis organisms. Inhibition by black tea was correlated with the total and individual theaflavin content of the two tea extracts determined by HPLC. Metronidazole-resistant Trichomonas vaginalis strains were also inhibited by the black tea extract. The response of the organisms to the remaining preparations was variable and unique. We observed no effect of the black tea extract on common normal flora bacteria. CONCLUSIONS: The results suggest that the black tea, and to a lesser degree green tea, grape seed, and pomegranate extracts might present possible natural alternative therapeutic agents to treat Trichomonas vaginalis infections in humans and the related trichomonad infections in animals, without negatively affecting the normal flora.

Effect of Enterococcus Faecium Strain SF68 on Gastrointestinal Signs and Fecal Microbiome in Cats Administered Amoxicillin-Clavulanate.

Some cats develop vomiting or diarrhea during administration of some antibiotics such as amoxicillin-clavulanate but how often this occurs and the severity of disease is generally unknown. In people, one of the accepted indications for the use of probiotics is to attempt and lessen antibiotic-associated diarrhea. Enterococcus faecium strain SF68 (SF68; Purina® ProPlan® Veterinary Diets; FortiFlora™ Probiotic Supplement) is a commercially available probiotic available in many countries that has been shown to lessen diarrhea rates in cats housed in animal shelters. The objectives of this study were to describe the gastrointestinal abnormalities (clinical and microbiome) associated with the administration of amoxicillin-clavulanate to cats and to determine whether feeding SF68 could ameliorate those abnormalities. Laboratory reared domestic cats were administered amoxicillin-clavulanate for 7 days with or without SF68 for 14 days and monitored for vomiting and diarrhea and for changes in the gastrointestinal microbiome before and after antibiotic administration. Fecal scores > 5 on a 7-point scale were detected in 9 of 13 cats (69.2%) fed SF68 compared to 12 of 14 cats fed the placebo (85.7%). Fecal scores of 7 were only detected in the placebo group and when total diarrhea scores were compared between groups for days 1-11, the cats fed SF68 were statistically lower (P = 0.0058). Administration of amoxicillin-clavulanate led to decreased microbiome diversity, but differences between cats fed SF68 or the placebo were not detected. The results show administering amoxicillin-clavulanate orally to cats commonly induces diarrhea and alters the gastrointestinal microbiome, and that feeding the probiotic SF68 can lessen some associated clinical abnormalities.

In Vitro Susceptibility of Sporothrix brasiliensis to Essential Oils of Lamiaceae Family.

This study evaluated the chemical, cytotoxic and anti-Sporothrix brasiliensis properties of commercial essential oils of rosemary (Rosmarinus officinalis L.), oregano (Origanum vulgare L.) and marjoram (Origanum majorana L.). Chemical composition of the oils was identified through gas chromatography with flame ionization detector, and cytotoxicity was performed through MTT assay in VERO cell line. Anti-S. brasiliensis activity was performed according to the CLSI M38-A2 guidelines using isolates obtained from cats and dogs. The major compounds found were carvacrol in the oregano oil (73.9 %) and 1,8-cineole in rosemary and marjoram oils (49.4 and 20.9 %, respectively). All S. brasiliensis isolates were susceptible to the plant oils, including itraconazole-resistant ones. Marjoram and rosemary oils showed MIC90 of 0.56 and 1.12 mg ml-1, and MFC90 of 4.5 and 9 mg ml-1, respectively. For oregano oil, a strong antifungal activity was observed with MIC90 and MFC90 values ≤0.07 mg ml-1. The weakest cytotoxicity was observed for rosemary oil. Further studies should be undertaken to evaluate the safety and efficacy of these essential oils in sporotrichosis.

Treatment of feline giardiasis during an outbreak of diarrhoea in a cattery: potential effects on faecal Escherichia coli resistance patterns.

OBJECTIVES: An outbreak of diarrhoea involving 16 cats at a cattery in Norway was investigated. Treatment and control of the outbreak were the primary objectives, but the effects of treatment on the antimicrobial resistance profiles of Escherichia coli isolated from faeces were also investigated. METHODS: Faecal samples were investigated for Giardia cysts by immunofluorescence microscopy, and multi-locus genotyping was performed to determine the Giardia genotype. Faecal E coli were assessed, before and after treatment for giardiasis, for antimicrobial resistance. RESULTS: The outbreak was probably caused by Giardia duodenalis, Assemblage F. Although infection was eliminated in most cats following treatment with fenbendazole, over 30% of the infected cats required a second treatment round (combined fenbendazole and metronidazole). Investigation of sensitivity to antibacterial drugs of E coli that had been isolated both prior to and following treatment demonstrated that fenbendazole treatment may select for resistant bacteria. CONCLUSIONS AND RELEVANCE: Controlling Giardia infections in dense cat populations can be challenging, and requires strict hygiene measures. In cases where fenbendazole alone does not result in treatment success, a combination treatment with fenbendazole and metronidazole may be effective. Although this study did not include untreated controls, we suggest that the potential for changes in gut microbiota and antimicrobial resistance development should be considered when choosing antiprotozoal drugs, particularly in cases of treatment failure and where repeat treatment is required.

Management of endemic Microsporum canis dermatophytosis in an open admission shelter: a field study.

Endemic Microsporum canis dermatophytosis was identified in a large, open admission, private, no-kill shelter that admitted >1200 cats per year. Fungal culture (FC) screening revealed that 166/210 (79%) and 38/99 (38%) cats in the non-public and public area were culture positive, respectively. However, pending screening FC results, the 99 cats in the public area were treated with once-weekly lime sulfur rinses and monitored with once-weekly FC. Cats in the non-public area were not treated. When FC results were available, cats were separated into low-risk (n = 61) and high-risk (n = 38) groups based upon the presence or absence of skin lesions. Low-risk cats continued to receive once-weekly topical lime sulfur and rapidly achieved culture-negative status. High-risk cats were divided into two groups based upon the number of colony-forming units/plate (low or high). All 38 cats were treated with twice-weekly lime sulfur and oral terbinafine and within 6-7 weeks only 5/38 cats were still FC-positive. These cats were moved to a separate room. Dermatophytosis was eradicated within 5 months; eradication was prolonged owing to reintroduction of disease into the remaining room of cats under treatment from three kittens returning from foster care. Continued admissions and adoptions were possible by the institution of intake procedures that specifically included careful Wood's lamp examination to identify high-risk cats and use of a 'clean break strategy'.

Potential effects of Trachyspermum copticum essential oil and propolis alcoholic extract on Mep3 gene expression of Microsporum canis isolates.

OBJECTIVE: The purpose of this study was to evaluate the effects of Trachyspermum copticum (T. copticum) essential oil and propolis alcoholic extract on growth and transcription of Mep3 gene of Microsporum canis (M. canis) strains. METHODS: The antifungal activity was assayed by broth macrodilution method. Fungal isolates were grown in soy peptone liquid medium and treated with T. copticum oil and propolis extract. Total RNAs of M. canis were subjected to reverse transcription-polymerase chain reaction (RT-PCR). Specific primers of Actin and Mep3 genes were used. RESULTS: The results revealed that MIC values of T. copticum oil against M. canis strains were ranged from 0.2-30.5 µg/mL, with 42.3% of the strains inhibited at 0.9 µg/mL. In addition, MIC values of propolis extract against M. canis strains were ranged from 0.2-488.2 µg/mL, with 34.6% of the strains inhibited at 0.9 µg/mL. RT-PCR analysis of Mep3 and Actin expression showed DNA fragments of 661 and 690 bp amplified in all isolates before treatments with T. copticum essential oil and propolis extract. Both T. copticum and propolis completely inhibited the expression of Mep3 gene. CONCLUSION: We reported for the first time that T. copticum and propolis inhibits the expression of Mep3 gene in M. canis strains in relation to a remarkable inhibition in protease production by the fungus.

Treatment of shelter cats with oral terbinafine and concurrent lime sulphur rinses.

BACKGROUND: Dermatophytosis is an important contagious and infectious skin disease in an animal shelter. Itraconazole is the commonly used systemic antifungal drug, but it is expensive in some countries and, at times, difficult to obtain. Terbinafine is a fungicidal allylamine with documented in vitro and in vivo efficacy against Microsporum canis in pet cats and in cats with experimental infections. HYPOTHESIS/OBJECTIVES: To describe the use of oral terbinafine for the treatment of M. canis dermatophytosis in shelter cats. METHODS: The response to treatment of 85 shelter cats with naturally occurring M. canis dermatophytosis was monitored by examination, weekly toothbrush fungal cultures and the number of colony-forming units on fungal culture plates. Cats were treated with either 14 (n = 21) or 21 days (n = 64) of terbinafine per os (p.o.) along with concurrent twice weekly lime sulphur rinses and daily environmental disinfection. RESULTS: Cats treated with 14 days of terbinafine p.o. showed an initial response to therapy but by week 6 had relapsed and required rescue therapy with a course of itraconazole (10 mg/kg p.o.) to obtain a cure. Cats treated with 21 days of terbinafine p.o. showed a response to treatment similar to published reports using itraconazole p.o. for 21 days. The mean and median number of days to mycological cure was 22.70 (range 13-39). Terbinafine was well tolerated. None of the cats developed oral lesions postgrooming of lime sulphur rinses. CLINICAL SIGNIFICANCE: Where itraconazole is not available, substitution with terbinafine in established protocols may allow shelters to treat cats that otherwise would go untreated.

In vitro potency and efficacy favor later generation fluoroquinolones for treatment of canine and feline Escherichia coli uropathogens in the United States.

Information regarding in vitro activity of newer fluoroquinolones (FQs) is limited despite increasing resistance in canine or feline pathogenic Escherichia coli (E. coli). This study describes in vitro potency and efficacy toward E. coli of seven FQs grouped according to similarities in chemical structure: enrofloxacin, ciprofloxacin, orbifloxacin (first-group), levofloxacin, marbofloxacin (second-group) and pradofloxacin, moxifloxacin (third-group; latest S, S-pyrrolidino-piperidine at C-7). Potency measures included minimum inhibitory concentration (MIC) (geometric mean MIC, MIC(50), MIC(90)); and mutant prevention concentration (MPC) for FQ susceptible isolates only. In vitro efficacy measures included relative susceptibility (MIC(BP-S):MIC) or resistance (MIC:MIC(BP-R)) and mutant selection window (MSW) (MPC:MIC). For enrofloxacin susceptible isolates, mean MIC (µg/ml) was least for each third-group drug and ciprofloxacin and greatest for enrofloxacin and orbifloxacin (P = 0.006). For enrofloxacin susceptible isolates, MPC were below MIC:MIC(BP-R) and least for pradofloxacin (0.29 ± 0.16 µg/ml) and greatest for enrofloxacin (1.55 ± 0.55 µg/ml) (P = 0.006). MSW was least for pradofloxacin (55 ± 30) and greatest for ciprofloxacin (152 ± 76) (P = 0.0024). MIC(BP-S):MIC was greatest (P = 0.025) for pradofloxacin (190.1 ± 0.61) and least for enrofloxacin (23.53 ± 0.83). For FQ susceptible isolates, FQs MIC:MIC(BP-R) may serve as a surrogate for MPC. Because in vitro efficacy was greatest for pradofloxacin; it might be preferred for treatment of urinary tract infections (UTIs) associated with FQ susceptible E. coli uropathogens.

Antimicrobial resistance and pharmacodynamics of canine and feline pathogenic E. coli in the United States.

Percent resistance and minimum inhibitory concentrations (MIC) were described for canine (n = 301) and feline (n = 75) pathogenic Escherichia coli (E. coli) isolates solicited during May 2005 to Sep 2005 from the Clinical Pharmacology Laboratory at Auburn University (n = 165) or commercial diagnostic laboratories ([CDL]; n = 211) from four regions in the USA. Drugs tested were amoxicillin (AMX), amoxicillin trihydrate/clavulanate potassium (AMXC), cefpodoxime (CFP), doxycycline (DXY), enrofloxacin (ENR), gentamicin (GM) and trimethoprim-sulfamethoxazole (TMS). Urinary isolates were most common (n = 174). Percent resistance was greatest for isolates from the respiratory tract, urine, and skin compared with the ear. Resistance was also greatest for samples sent from the south and central states compared with the western states (P ≤ 0.001). Percent resistance by drug was AMX (46 ± 2.6%) > AMXC (37 ± 2.5%) > CFP (21.8 ± 2%) = DXY (22 ± 2.1%) = ENR (20 ± 2.1%) = TMS (19 ± 2%) > GM (12 ± 1.7%). There was a significant difference in resistance between the different antibiotic drugs (P ≤ 0.001). Population MIC distributions were bimodal, and MICs were highest in samples from the southern states (P ≤ 0.001). E. coli resistance may limit its empirical treatment. For susceptible isolates, AMX and AMXC may be least effective and TMS most effective.

In vitro and in vivo antifungal activity of some essential oils against feline isolates of Microsporum canis.

The treatment of dermatophytoses due to Microsporum canis is cumbersome and relapses can occur. Volatile essential oils (EOs) obtained from plants would seem to represent suitable tools to contrast mycoses both in human and animals. The anti-M. canis activity of some EOs chemically characterized was evaluated both in vitro and in vivo. Eleven feline isolates of M. canis were tested by microdilution against EOs extracted from Thymus serpillum, Origanum vulgare, Rosmarinus officinalis, Illicium verum and Citrus limon. A mixture composed by 5% O. vulgare, 5% R. officinalis and 2% T. serpillum, in sweet almond oil was administered to seven infected, symptomatic cats. T. serpillum and O. vulgare showed the lowest MICs, followed by I. verum, R. officinalis and C. limon. The assay performed on mixture showed that antimycotic activity of each component was enhanced. Four out of seven treated cats recovered both clinically and culturally. T. serpillum and O. vulgare EOs showed a strong antifungal activity. Preliminary data suggest a possible application in managing feline microsporiasis. Considering the potential zoonotic impact of this infection, the use of alternative antimycotic compounds would be of aid to limit the risk of environmental spreading of arthrospores.

Polymerase chain reaction-based identification of clinically relevant Pasteurellaceae isolated from cats and dogs in Poland.

A set of polymerase chain reaction (PCR) assays for identification of the most important Pasteurellaceae species encountered in cats and dogs were developed. Primers for Pasteurella multocida were designed to detect a fragment of the kmt, a gene encoding the outer-membrane protein. Primers specific to Pasteurella canis, Pasteurella dagmatis, and Pasteurella stomatis were based on the manganese-dependent superoxide dismutase gene (sodA) and those specific to [Haemophilus] haemoglobinophilus on species-specific sequences of the 16S ribosomal RNA gene. All the primers were tested on respective reference and control strains and applied to the identification of 47 canine and feline field isolates of Pasteurellaceae. The PCR assays were shown to be species specific, providing a valuable supplement to phenotypic identification of species within this group of bacteria.

Fluoroquinolones: then and now.

Fluoroquinolones were discovered in the 1960s as a derivative of the antimalarial drug chloroquine. Over the past 40 years, many fluoroquinolones have been developed for use in human and veterinary medicine. As with all classes of antibiotics, resistance to fluoroquinolones is a serious concern, and multiple avenues for resistance are being investigated. Resistance-associated point mutations in bacterial DNA and, more recently, plasmid-mediated resistance have been reported in both human and veterinary bacterial isolates. This article reviews the history and most current literature on fluoroquinolones approved for use in dogs and cats and the spectra of activity, mechanisms of action, resistance patterns, and recommendations for appropriate clinical use of these drugs.