Epidemiology, Clinical Characteristics, and Antimicrobial Susceptibility Profiles of Human Clinical Isolates of Staphylococcus intermedius Group

Abstract

The veterinary pathogens in the group (SIG) are increasingly recognized as causes of human infection. Shared features between SIG and may result in the misidentification of SIG in human clinical cultures. This study examined the clinical and microbiological characteristics of isolates recovered at a tertiary-care academic medical center. From 2013 to 2015, 81 SIG isolates were recovered from 62 patients. Patients were commonly ≥50 years old, diabetic, and/or immunocompromised. Documentation of dog exposure in the electronic medical record was not common. Of the 81 SIG isolates, common sites of isolation included 37 (46%) isolates from wound cultures and 17 (21%) isolates from respiratory specimens. Although less common, 10 (12%) bloodstream infections were documented in 7 unique patients. The majority of SIG (65%) isolates were obtained from polymicrobial cultures. In comparison to isolates from the same time period, significant differences were noted in proportion of SIG isolates that were susceptible to doxycycline (74% versus 97%, respectively; < 0.001), trimethoprim-sulfamethoxazole (65% versus 97%, respectively; < 0.001), and ciprofloxacin (78% versus 59%, respectively; < 0.01). Methicillin resistance (MR) was detected in 12 (15%) of 81 SIG isolates. All MR isolates detected by an oxacillin disk diffusion test would have been misclassified as methicillin susceptible using a cefoxitin disk diffusion test. Thus, SIG is recovered from human clinical specimens, and distinction of SIG from is critical for the accurate characterization of MR status in these isolates.

Research and identification of Staphylococcus Pasteur, 1880 (Bacillales Staphylococcaceae) potentially zoonotic isolated from Sicilian dogs

“…The samples of amplified DNA were purified with a commercial kit confirms the emergence of the phenomenon of resistence to antibiotics also in the veterinary field, paying particular attention to the high presence of penicillin-resistant strain (90%), methicillin (47.7%), and amoxicillin (27.7%). The data obtained show a strong sensitivity to difluoroquinolones in a higher percentage than the one cited in a previous literature (Humphries et al, 2016;Yarbrough et al, 2018).…”

Performance of Five Commercial Identification Platforms for Identification of Staphylococcus delphini

“…There is only a single report of human infection due to S. delphini (although this may be a function of the inability of biochemical systems to accurately identify this organism, resulting in underestimation of its prevalence in the human population), and to the best of our knowledge, mecA-mediated ␤-lactam resistance has not been documented in S. delphini (all 21 isolates included in this study were negative for mecA). However, methicillin resistance in S. pseudintermedius increased in canine isolates from less than 5% in 2001 to near 30% in 2007 (14), and it has subsequently emerged in human-associated isolates (9,10,15). In many instances, mecA-mediated ␤-lactam resistance in S. pseudintermedius is accompanied by resistance to other classes of antimicrobials (e.g., fluoroquinolone, tetracycline, and lincosamide) commonly used in veterinary and human medicine (22).…”

Potent, specific MEPicides for treatment of zoonotic staphylococci

“…In addition, these organisms cause zoonotic infections in humans that are clinically indistinguishable from infections with S. aureus including pneumonia, skin and soft tissue infections, hardware infections, and bacteremia [1][2][3][4][5]. Newer clinical microbiological techniques, such as mass spectrometry, now readily distinguish S. aureus from zoonotic coagulase-positive staphylococci, which were previously often misidentified [3,6,7]. Thus, there is a growing recognition of the importance of zoonotic staphylococci in human disease.…”