Adherence of Staphylococcus intermedius to canine corneocytes in vitro

This study investigated the in vitro adherence of Staphylococcus intermedius to canine corneocytes, collected from a healthy dog using double-sided adhesive tape. Adherence was shown to depend on duration (P < 0.001) and temperature of incubation (P < 0.001) and the concentration of bacteria (P < 0.001). Isolates of S. intermedius from lesions of pyoderma were not generally more adherent to healthy canine skin than were isolates from healthy dogs. Significant differences in adherence were demonstrated between individual isolates within both groups (P < 0.001). The study suggests that among S. intermedius there is no correlation between virulence and adherence to canine corneocytes in vitro. The finding may be important for the potential use of avirulent variants of S. intermedius as antagonistic strains against canine pyoderma. However, more studies are needed to compare the adherence of the isolates to skin cells obtained from dogs with diseases predisposed to pyoderma.     

Adherence by Staphylococcus intermedius to canine corneocytes: a preliminary study comparing noninflamed and inflamed atopic canine skin

The adherence by three strains of Staphylococcus intermedius to corneocytes collected from healthy dogs was compared to the adherence to corneocytes collected from the inflamed (erythematous) and noninflamed (normal appearing) skin of dogs suffering from atopic dermatitis. All three strains of S. intermedius adhered in greater numbers to corneocytes from both inflamed and noninflamed atopic skin than to corneocytes from healthy dogs. Adherence was greatest to corneocytes from inflamed atopic skin but one strain showed no statistical difference for adherence to inflamed and noninflamed atopic skin. These findings suggest that S. intermedius adheres extensively to both inflamed and noninflamed canine atopic skin. This may be important in the colonization of atopic skin by this microorganism. Strain variation in the ability of S. intermedius to adhere to canine atopic corneocytes is probable.     

Adherence by Staphylococcus intermedius to canine keratinocytes in atopic dermatitis

The adherence of Staphylococcus intermedius to canine keratinocytes in normal dogs was compared to that in dogs suffering from atopic dermatitis, primary seborrhoea and bacterial pyoderma. Statistically significant greater adherence by S. intermedius to keratinocytes occurred in atopic dogs and dogs suffering from pyoderma when compared with the normal group (P < 0.01) and dogs suffering from primary seborrhoea (P < 0.05). This is similar to the results of a study of human atopic dermatitis by Cole and Silverberg (1986) who demonstrated increased adherence by S. aureus to keratinocytes from atopic dermatitis patients when compared with adherence to keratinocytes in a variety of non-atopic dermatoses. This increased adherence by pathogenic staphylococci to keratinocytes may in part explain the high incidence of staphylococcal pyoderma seen in both canine and human patients suffering from atopic dermatitis.     

A comparison of adherence by four strains of Staphylococcus intermedius and Staphylococcus hominis to canine corneocytes collected from normal dogs and dogs suffering from atopic dermatitis

The aim of this study was to compare the adherence of four strains of Staphylococcus intermedius and a single strain of Staphylococcus hominis to corneocytes from both normal dogs and dogs suffering from atopic dermatitis. Cells from the skin surface, corneocytes, were collected from 10 normal dogs and 10 dogs suffering from atopic dermatitis. Four strains of S. intermedius, three isolated from canine pyoderma skin lesions (strains A, B and C), and one isolated form from canine synovial membrane sample from a case of septic arthritis (strain D) were compared. S. hominis, which is not normally associated with canine disease, was also evaluated for its ability to adhere to canine corneocytes. S. hominis did not adhere to canine corneocytes. All four strains of S. intermedius adhered well to canine corneocytes collected from both normal and atopic dogs. All strains of S. intermedius showed statistically greater adherence to corneocytes collected from atopic dogs compared with those collected from normal dogs. It was concluded that the adherence assay employed here showed that S. hominis does not adhere to canine corneocytes, S. intermedius adheres preferentially to atopic corneocytes.     

Molecular characterization of Staphylococcus intermedius carriage by healthy dogs and comparison of antimicrobial susceptibility patterns to isolates from dogs with pyoderma

We conducted an epidemiological study of Staphylococcus intermedius using arbitrarily primed PCR (AP-PCR) and antibiograms. One hundred and twenty-five S. intermedius isolates were recovered from the oral cavity and/or cranial hair coat of healthy dogs enrolled in a pet therapy program. Commensal S. intermedius was cultured from 32% of the oral cavity cultures and 13% of the cranial hair coat cultures. We characterized the colonization of the dogs as transient, intermittent, or persistent. For dogs characterized as persistently colonized, 73% of the isolates came from the oral cavity. These isolates were also genotyped by AP-PCR. A single major AP-PCR type was observed in 91% of the dogs (n=22); minor variations were frequently observed in these major types. Antibiograms of these commensal isolates were compared to antibiograms from 97 historical clinical isolates (1988-1992) obtained from cases of canine pyoderma. Resistance was most often observed to penicillin (64% and 55%) and tetracycline (38% and 38%) among the commensal and clinical isolates, respectively. The commensal isolates were significantly less resistant to erythromycin, clarithromycin, clindamycin, and trimethoprim/sulfamethoxazole. Our data suggests that differences in both genotype and antimicrobial susceptibility phenotypes exist among S. intermedius strains isolated from different anatomic sites from the same dog and supports the opportunistic nature of S. intermedius in canine infections.     

Aspects of the humoral immune response to Staphylococcus intermedius in dogs with superficial pyoderma,deep pyoderma and anal furunculosis

Bacterial infection (pyoderma) of the canine skin is largely caused by Staphylococcus intermedius and may be a superficial or deep infection. Pyoderma may be a primary, idiopathic disease or secondary to a range of other dermatological disorders. In this study, the serum concentrations of IgG, IgA, antistaphylococcal IgG and antistaphylococcal IgA were measured by ELISA in normal dogs (n = 22), dogs with idiopathic deep pyoderma (n = 22), atopic dermatitis and superficial pyoderma (n = 24), atopic dermatitis without pyoderma (n = 25), flea bite dermatitis with superficial pyoderma (n = 8), pustular demodicosis (n = 8) and German shepherd dogs with anal furunculosis (n = 28). The serum IgG was significantly increased in dogs with atopy and superficial pyoderma (p < 0.001), and lower than normal in dogs with idiopathic deep pyoderma (p < 0.015). The concentration of serum IgA was significantly lower than normal in dogs with atopy uncomplicated by pyoderma (p < 0.015). The concentration of antistaphylococcal IgG in all clinical sera was significantly elevated (p < 0.001) when compared to normal dogs but concentrations of antistaphylococcal IgA were no greater than in normal dogs. Western blotting analysis for determination of the specificity of serum IgG antistaphylococcal antibody revealed that there were nine major epitopes. Discriminant analysis demonstrated that particular combinations of these epitopes were recognised more frequently by sera from dogs in different clinical groups.     

Efficacy of tylosin tablets for the treatment of pyoderma due to Staphylococcus intermedius infection in dogs.

Tylosin tablets (20 mg/kg, q12h) were administered orally to 21 dogs with superficial or deep staphylococcal pyodermas. Response to therapy was excellent in 90.5% of the dogs, and in vitro susceptibility testing correlated perfectly with therapeutic response. Duration of therapy varied from 17 to 91 days, with an average of 33 days. Relapses occurred in 28.6% of the dogs within a three-month period. No side effects were reported. Under the conditions of the study, tylosin was an effective and safe antibiotic for the treatment of staphylococcal pyoderma in dogs.     

Aspects of nasal, oropharyngeal and anal carriage of Staphylococcus intermedius in normal dogs and dogs with pyoderma

Aspects of carriage of Staphylococcus intermedius were studied in three groups of dogs. In 150 normal dogs presenting for annual booster inoculations, carriage rates for S . intermedius in the anterior nares (36%) and on the anal ring (36%) were recorded. In 44 dogs presented for routine elective surgery, carriage of S . intermedius was higher on the caudal nares (41%) than on the anterior nares (34%), oropharynx (25%) or anal ring (30%) allowing an assessment of the accuracy of basing nasal carriage rates on swabbing the anterior nares alone. A new finding was that animals from multidog households had significantly higher ( P < 0.005) nasal and anal carriage rates than dogs from single-dog households. In 33 dogs with superficial pyoderma, carrier rates were similar to those reported by others and significantly higher than in the other two groups with regard to both nasal and anal carriage ( P < 0.05 and P < 0.005, respectively).     

Efficacy of orbifloxacin tablets for the treatment of superficial and deep pyoderma due to Staphylococcus intermedius infection in dogs

Orbifloxacin tablets were administered orally to 23 dogs with superficial and/or deep staphylococcal pyoderma. Response to therapy was excellent in 95.6% of the dogs. Duration of therapy varied from 21 to 40 days (average 29 days) for dogs having only superficial infections, and from 25 to 150 days (average 72 days) for dogs having deep infections. Relapses occurred in 18% of the dogs within a 3-month period. One dog developed a presumed adverse cutaneous drug reaction. Under the conditions of this study, orbifloxacin was an effective, safe, and convenient antibiotic for the treatment of superficial and deep staphylococcal pyoderma in dogs.     

Characteristics of Staphylococcus intermedius isolates from diseased and healthy dogs

Staphylococcus intermedius isolates from diseased and healthy dogs were examined for production of extracellular enzymes and toxins, and phage patterns. There were no significant differences between the two groups of isolates in the production rates of DNase, protease, lipase, gelatinase, hyaluronidase, hemolysins, protein A, and TSST-1, or in phage patterns. But the production rate of enterotoxins in isolates from diseased dogs was significantly higher than that in isolates from healthy dogs. PFGE analysis was performed with isolates from different body sites in individual dogs. In 3 of 6 healthy dogs, identical PFGE patterns were seen in isolates from the nares, external auditory meatus or skin. The remaining 3 dogs yielded isolates of different patterns. In 4 of 6 diseased dogs, identical patterns were seen in isolates from lesions as well as from the other normal sites.     

Isolation of Staphylococcus schleiferi from healthy dogs and dogs with otitis, pyoderma, or both

OBJECTIVE: To determine the frequency of isolation and susceptibility patterns of Staphylococcus schleiferi from healthy dogs and dogs with otitis, pyoderma, or both that had or had not received antimicrobial treatment. DESIGN: Prospective study. ANIMALS: 50 dogs. PROCEDURE: Dogs were allocated to 1 of 4 groups: healthy dogs (n=13), dogs without otitis but with pyoderma (10), dogs with otitis but without pyoderma (11), and dogs with otitis and pyoderma (16). Bacteriologic culture of ear swab specimens was performed in all dogs. Bacteriologic culture of skin swab specimens was also performed in dogs with concurrent pyoderma. Isolates were identified as S schleiferi subsp schleiferi or S schleiferi subsp coagulans on the basis of growth and biochemical characteristics. RESULTS: S schleiferi was not isolated from any dogs with pyoderma only. Staphylococcus schleiferi subsp schleiferi was isolated from the ears of 2 healthy dogs, and the skin and ears of 2 dogs and the skin of 1 dog with otitis and pyoderma. Staphylococcus schleiferi subsp coagulans was isolated from the ears of 3 dogs with otitis only, and the ears of 6 dogs and the skin of 2 dogs with otitis and pyoderma. One of the S schleiferi subsp schleiferi isolates from ears, 2 of the S schleiferi subsp coagulans isolates from ears, and 1 of the S schleiferi subsp coagulans isolates from the skin were resistant to methicillin. One methicillin-resistant isolate from the ears and 1 from the skin were also resistant to fluoroquinolones. CONCLUSIONS AND CLINICAL RELEVANCE: S schleiferi subsp schleiferi was detected in healthy dogs and dogs with otitis and pyoderma. Methicillin-resistant and -susceptible S schleiferi subsp schleiferi and S schleiferi subsp coagulans were detected as the predominant organisms in dogs with otitis.     

Efficacy of clindamycin hydrochloride capsules for the treatment of deep pyoderma due to Staphylococcus intermedius infection in dogs.

Clindamycin hydrochloride capsules (11 mg/kg body weight, q24 h) were administered orally to 20 dogs with deep staphylococcal pyoderma. Response to therapy was excellent in 100% of the dogs. Duration of therapy varied from 21 to 91 d, with an average duration of 45 d. Relapses occurred in 25% of the dogs within a 3-month period. One dog vomited when the clindamycin was given on an empty stomach. Under the conditions of the study, clindamycin was an effective, safe, and convenient antibiotic for the treatment of deep staphylococcal pyoderma in dogs.     

Antimicrobial susceptibility of Staphylococcus intermedius isolated from healthy and diseased dogs

A total of 90 strains of Staphylococcus intermedius isolated from dogs were examined for antimicrobial susceptibility. There were no significant differences in the distribution patterns of MICs between strains from 1982 to 1985 and those from 1999, and between strains from healthy dogs and those from diseased dogs. All of the strains were susceptible to ABPC, DMPPC, CEX, TDM, ERFX, BFLX, and FF at concentrations of 0.05 to 6.25 microg/ml. The MICs of OTC, KM, EM, AIV-TS, and LCM were distributed in a broad range of 0.1 to >100 microg/ml, indicating the existence of resistant as well as susceptible populations of S. intermedius. Thirty-three strains (36.7%) were resistant to one or more anitmicrobial agents such as OTC (n=32), KM (n=9), EM (n=7), AIV-TS (n=7), and LCM (n=7).     

Transmission of multiple antimicrobial-resistant Staphylococcus intermedius between dogs affected by deep pyoderma and their owners

The occurrence of antimicrobial-resistant Staphylococcus intermedius strains was investigated in 13 dogs affected by deep pyoderma, their owners and 13 individuals without daily contact with dogs (control group). A total of 90 canine and 33 human S. intermedius isolates were typed by pulsed field gel electrophoresis (PFGE) to determine their possible identity. The occurrence of S. intermedius in dog-owners was significantly higher compared with the control group (Fisher's exact test, P=0.03), with S. intermedius being detected in seven dog-owners and in one individual not exposed to dogs. The results of the PFGE analysis showed that six out of 13 (46%) owners carried strains identical to those isolated from their dogs. Strains detected in both dogs and humans were resistant up to five different antimicrobial classes, including penicillins, fusidic acid, macrolides/lincosamides, tetracycline and chloramphenicol. Based on the results of this study, owners of dogs affected by deep pyoderma often carry multiple antimicrobial-resistant strains of S. intermedius occurring in their dogs. Independent of the direction and modalities of transmission, this finding raises questions concerning the possible transfer of resistance genes from canine S. intermedius to human pathogenic staphylococci.     

Heterogeneity of Staphylococcus pseudintermedius isolates from atopic and healthy dogs

Staphylococcus pseudintermedius is part of the normal canine flora but frequently causes pyoderma in canine atopic dermatitis (AD). This study aimed to determine whether particular S. pseudintermedius strains were associated with AD and/or pyoderma. Ninety‐six S. pseudintermedius isolates from the ear, nares, perineum and lesions of 21 atopic and 16 healthy dogs were lysed with proteinase K and digested with 40 U SmaI. Restriction products were separated using pulsed‐field gel electrophoresis (PFGE) with an Oxford S. aureus control and lambda‐ladder DNA concatomer markers. A dendrogram was constructed by the unweighted pair group method. All isolates showed a ≥56% similarity coefficient. Nine distinct PFGE clusters were identified, as follows: five from both atopic and healthy dogs; three from atopic dogs only; and one from healthy dogs only. Nine clusters were isolated from the nares, eight from the perineum, five from the ears and six from pyoderma lesions. There were no significant differences in the frequency of isolation from atopic or healthy skin, body sites or infected lesions for any of the clusters. Two of six healthy dogs and 18 of 20 atopic dogs with multiple isolates had closely related isolates (less than three band differences) at more than one sampling site. Isolates from pyoderma lesions were closely related to at least one mucosal isolate in 11 of 16 dogs. Staphylococcus pseudintermedius isolates appear to be heterogeneous, and colonization or infection of atopic skin was not associated with any particular strain or cluster of strains.     

Frequency of superantigen-producing Staphylococcus intermedius isolates from canine pyoderma and proliferation-inducing potential of superantigens in dogs

This preliminary study investigated the potential role of staphylococcal superantigens in the pathogenesis of canine pyoderma. The staphylococcal enterotoxins A (SEA), SEB, SEC and SED, and the toxic shock syndrome toxin-1 (TSST-1) were assayed in isolates from skins of dogs with pyoderma. Culture supernatants from 25 of 96 isolates were positive for multiple superantigens, with SEA and SEC being the most frequently detected. In in vitro stimulation of canine peripheral blood mononuclear cells and quantitative flow cytometry revealed that low concentrations of SEA and SEB were potent stimulators of blastogenesis of T cells.