Broth-disk elution determination of antimicrobial susceptibility of selected anaerobes isolated from animals.
Explore the source record for details and available documents.
Biomedical subjects
Publications and source records attributed to S S Jang.
Explore the source record for details and available documents.
Explore the source record for details and available documents.
Three hundred fifty-six animal isolates of indole-positive urease-negative cultures of Pasteurella, which would formerly have been classified as P. multocida, were examined with respect to their relationship to the recently described P. multocida subspecies (ssp.) multocida, septica, and gallicida and P. canis, P. stomatis/Taxon 16, and Pasteurella sp. B. Two hundred sixty-three (73.9%) of the cultures could be identified with one of these taxa, and 93 isolates (26.1%), representing 17 different biotypes, were unassignable. Pasteurella multocida ssp. multocida was the predominant taxon throughout and in most of the 25 animal species from which isolations were made. In dogs, P. canis was the most frequent. Different degrees of host predilection were observed also in P. multocida ssp. septica for cats, P. canis for sheep, and 2 of the unassignable biotypes for cattle and dogs, respectively. Overall, the respiratory tract was the most frequent source of isolates, but a propensity of P. multocida ssp. septica for localization in the central nervous system of cats was noted.
The most common bacterial species isolated from the vaginas of 37 healthy rhesus macaques were Streptococcus viridans, coagulase negative Staphylococcus, Mobiluncus curtisii ss. curtisii, Corynebacterium renale-like organisms, Peptostreptococcus anaerobius, Gardnerella-like organisms, and other Corynebacterium species. The vaginal flora of the rhesus macaque differs from that previously reported for five other primate species. A two-year retrospective review of clinical cases of vaginitis and metritis found Escherichia coli and coagulase positive Staphylococci to be the most common pathogens isolated.
During the years 1984 through 1987 2,574 isolates of obligately anaerobic bacteria were isolated from samples submitted for analysis. The most common anaerobic isolates were members of the genus Bacteroides, representing 44.6% of the isolates. Of these, the most commonly isolated identifiable microorganisms were bile-resistant and nonpigmented, belonging to the B fragilis group of Bacteroides. Importantly, obvious predilections for any one species or group of Bacteroides were not apparent for animal or site (condition), except that the proportion of isolates belonging to the nonpigmented, bile-resistant group obtained from the respiratory tract was significantly (P less than 0.005) higher than that not belonging to this group. On the other hand, the proportion of isolates of the non-pigmented, bile-resistant group obtained from abscesses was significantly lower than that not belonging to this group.
The combination of ampicillin together with trimethoprim-sulfonamide is sometimes used as a broad-spectrum antimicrobial regimen for treatment of dogs with bacterial infections of unknown etiopathogenesis. To determine whether this combination is indeed broad spectrum, we analyzed susceptibility data derived from commonly encountered bacterial agents in dogs. A total of 381 isolates from 344 cases was studied. Overall, 80 (20.9%) of the 381 isolates were resistant to ampicillin and to trimethoprim-sulfonamide; 159 (41.7%) were resistant to ampicillin, but susceptible to trimethoprim-sulfonamide; 131 (34.4%) were susceptible to both ampicillin and trimethoprim-sulfonamide; and 11 (2.9%) were susceptible to ampicillin, but resistant to trimethoprim-sulfonamide. Of isolates susceptible to ampicillin and/or trimethoprim-sulfonamide, 290 (96.3%) were susceptible to trimethoprim-sulfonamide (ampicillin increased the coverage by 3.7%). On the other hand, 142 (47.2%) were susceptible to ampicillin. In addition, with respect to agents most commonly encountered (members of the family Enterobacteriaceae and members of the genus Staphylococcus), combining ampicillin with trimethoprim-sulfonamide increased coverage by 2.2% over use of trimethoprim-sulfonamide alone. We contend, therefore, that use of ampicillin together with trimethoprim-sulfonamide does not result in an acceptable broad-spectrum antimicrobial regimen for treatment of bacterial disease in dogs.
Nutritionally variant streptococci (NVS) are nutritionally deficient viridans streptococci that require pyridoxal for growth. Although NVS are pathogenic in human beings, they have not been considered to be pathogenic in domestic animals. In 1982 and 1983, 24 isolates of NVS were recovered from horses with ulcerative keratitis. A retrospective study was done to determine the incidence of NVS in horses with corneal disease. The medical records of 249 horses (259 eyes) examined for clinical signs of corneal disease were reviewed. Nutritionally variant streptococci were isolated from approximately 13.5% of horses with ulcerative keratitis.
In a case-control study of risk factors associated with an episode of nosocomial Salmonella krefeld infection in dogs at the veterinary medical teaching hospital, data on 20 case dogs and 75 control dogs were obtained by review of hospital records. Univariate and multivariate statistical analyses were carried out for possible risk factors for infection to obtain odds of Salmonella krefeld isolation, given exposure to each risk factor of interest. Compared with control dogs, case dogs were 11.9 times more likely to have been fed rice, 7 times more likely to have had radiography done, 10.2 times more likely to have been a resident in ward 2, 5.6 times more likely to have been given antimicrobial agents orally, 11.3 times more likely to have been given antimicrobial agents parenterally, and 37.9 times more likely to have been given antimicrobial agents orally and parenterally (P less than 0.05).
Streptococcus pneumoniae serotype 23F was isolated from the blood and synovial fluid of an acutely ill, 15-year-old castrated male cat and from the nasopharynx of that regularly played with it, an infant child. Information presented supports the hypothesis that the infection was transmitted from child to cat.
Rational choice of an antimicrobial agent requires that the condition for which the drug is prescribed contain an infectious agent and, if so, knowledge of the susceptibility of the microorganism to antimicrobial drugs. Unfortunately, most infectious conditions necessitate the use of an antimicrobic drug before data from the microbiology laboratory are available. The data presented are meant to serve as a guide in the choice of antimicrobic drugs for treatment of infectious processes of the horse before knowledge of the nature of the microorganism isolated as well as its susceptibility to antimicrobic agents. What has been presented are the most commonly isolated microorganisms together with their susceptibility to antimicrobic drugs.
Actinobacillus suis-like organisms have been recognized in equine specimens at the University of California Veterinary Medical Teaching Hospital since 1975. The most common source (65%) of the organism was transtracheal washings. The organism was gram-negative, produced hemolysis on blood agar, and gave a positive reaction for oxidase, urease, o-nitrophenyl-beta-D-galactopyranoside, and esculin. Carbohydrate reactions were variable, consisting of 4 main patterns. Actinobacillus suis-like organisms were (90%) sensitive to therapeutic concentrations of amikacin, cephalothin, chloramphenicol, gentamicin, kanamycin, tetracycline, and trimethoprim-sulfamethoxazole. Other aerobic and anaerobic bacteria were recovered frequently with the organism.
Nine Thoroughbred racehorses were admitted with cellulitis (of one or more limbs) associated with coagulase-positive staphylococci. The right hindlimb was affected in 4 horses, the right forelimb in 2, the left hindlimb in 1, and both hindlimbs in 2. Typical abnormalities included high values for rectal temperature (9 horses) and heart rate (5 horses), hyperfibrinogenemia (7 horses), leukocytosis (7 horses), and neutrophilia (6 horses). The staphylococcal isolants were speciated in 3 horses and classified as Staphylococcus aureus. Complications included skin loss (5 horses), laminitis of the affected limb (2 horses), laminitis of the contralateral limb (4 horses), osteomyelitis and sequestrum formation (2 horses), and bacteremia (1 horse). Five horses were euthanatized because of the severity of the complications, ie, laminitis in 4 horses and severe skin loss in 1 horse. The remaining 4 horses were discharged from the clinic. At follow-up evaluation (mean, 16.7 months), the swelling in 3 of the horses had completely resolved. One horse returned to racing; of 2 used for pleasure riding, one was mildly lame. The remaining horse was not lame, but was used for breeding because of persistent swelling of the affected limb.
Actinomycotic mycetoma, a chronic, progressive infection of the subcutaneous tissue characterized by tumefaction, draining sinuses, and grains, was diagnosed in the right hindlimb of a young adult, male cat. The organisms that cause actinomycetoma are soil or plant saprophytes that gain entrance to the skin through abrasion or traumatic implantation. Streptomyces griseus, an organism generally considered to be a saprophyte, was cultured bacteriologically. Despite extensive surgery and long-term antibiotic therapy, the infection persisted, and the cat was euthanatized.
Four cases of disseminated aspergillosis caused by Aspergillus deflectus in German Shepherds are presented. Three of the cases, which involved multiple organs, terminated in euthanasia. One case, with bony involvement of the limbs and skull, lived. The unique morphological characteristic of the conidial head resembling a briar pipe led to the identification of A. deflectus. To the authors' knowledge these are the first reported cases of infections caused by A. deflectus in man or animal.
Salmonella belonging to 47 serotypes was isolated from animals at the University of California Veterinary Medical Teaching Hospital during the years 1974 to 1983. Salmonella belonging to 12 serotypes accounted for 89% of the 725 isolates. Salmonella typhimurium (including var copenhagen) was the most commonly isolated serotype, but during 1981 to 1983, S krefeld and S saint-paul were predominant. Certain serotypes seemed to be isolated more frequently from extraintestinal sources (S typhi-suis, S dublin). Although resistance to ampicillin, kanamycin, neomycin, streptomycin, and sulfonamides was common (greater than 60% of the isolates were resistant), resistance to chloramphenicol, gentamicin, and trimethoprim-sulfonamides was infrequent, except for isolates of S krefeld and S saint-paul.
Salmonella arizonae 61:1,5, was isolated in pure culture from the eye of a horse with unilateral ulcerative keratitis. The eye responded well to treatment with atropine sulfate and polymyxin B-bacitracin-neomycin ophthalmic ointments. In swab specimens taken after the lesion had healed, Salmonella was not found to be a constituent of the bacterial flora of the horse's eyes.
Of 3,133 clinical specimens obtained from domestic animals, 26% contained species of bacteria that were obligate anaerobes. Members of the genera Bacteroides, Fusobacterium, and Peptostreptococcus accounted for 77% of the isolates. On the average, 2 species of obligate anaerobes were found in each specimen, usually admixed with facultatively anaerobic bacteria. Of those specimens containing an obligate anaerobe, 20% contained one isolate that was resistant to penicillin, ampicillin, and cephalothin. These resistant isolates belonged to the genus Bacteroides, the most common being Bacteroides fragilis. Approximately one third of these penicillin-resistant isolates was resistant to tetracycline as well. All isolates were susceptible to chloramphenicol, tetracycline (excluding penicillin-resistant Bacteroides), metronidazole, and clindamycin.
From 1965 to 1983, Nocardia asteroides infection was diagnosed in 16 horses at the Veterinary Medical Teaching Hospital, University of California, Davis. In 2 of the cases, the infection was traumatic in origin and local in extent; the horses recovered without relevant antimicrobial therapy. Fourteen horses had pulmonary or disseminated infections that ended fatally. All 14 had various degrees of immunosuppression. Of these, 8 were Arabian foals with combined immunodeficiency disease and 3 were aged horses with hyperadrenocorticism secondary to ACTH-secreting pituitary tumors. Of the other 3, one had lymphosarcoma, another, hepatic disease presumed to be of toxic origin, and the third, a mixed disseminated bacterial infection.