ABSTRACT
Methicillin-resistant Staphylococcus (MRS) is a leading cause of skin and soft tissue infections in companion animals, with limited treatment options available due to the frequent cross-resistance of MRS to other antibiotics. In this study, we report the prevalence, species distribution, genetic diversity, resistance mechanism and cross-resistance patterns of MRS isolated from companion animal (mostly dog and cat) clinical cases submitted to Iowa State University Veterinary Diagnostic Laboratory (ISU VDL) between 2012 and 2019. The majority of isolates were identified as Staphylococcus pseudintermedius (68.3%; 2379/3482) and coagulase-negative Staphylococcus (CoNS) (24.6%; 857/3482), of which 23.9% and 40.5% were phenotypically resistant to methicillin, respectively. Cross resistance to other ß-lactams (and to a lesser extent to non-ß-lactams) was common in both methicillin-resistant S. pseudintermedius (MRSP) and CoNS (MRCoNS), especially when oxacillin MIC was ≥4 µg/mL (vs. ≥0.5−<4 µg/mL). The PBP2a protein was detected by agglutination in 94.6% (521/551) MRSP and 64.3% (146/227) MRCoNS. A further analysis of 31 PBP2a-negative MRS isolates (all but one MRCoNS) indicated that 11 were mecA gene-positive while 20 were negative for mecA and other mec genes by PCR. The resistance to last-resort anti-staphylococcal human drugs (e.g., tigecycline, linezolid, vancomycin) among the MRS tested was none to very low. Even though genotyping indicated an overall high level of genetic diversity (87 unique PFGE patterns and 20 MLST types) among a subset of MRSP isolates tested (n = 106), certain genotypes were detected from epidemiologically connected cases at the same or different time points, suggesting persistence and/or nosocomial transmission. These results indicate a relatively high prevalence of MRS from companion animals in the Midwestern US; therefore, it is important to perform routine susceptibility testing of Staphylococcus in veterinary clinical settings for the selection of appropriate antimicrobial therapy.
ABSTRACT
OBJECTIVES: There are several metabolic factors known to be important for the maintenance of bone and muscle function. Causes of deficiency are multifactorial and can include such things as geographic region, latitude, and socioeconomic factors. The purpose of this study was to determine the prevalence of metabolic deficiencies. SETTING: Level 1, urban trauma center. DESIGN: Prospective laboratory evaluation. PATIENTS: The subjects included 652 consecutive admits to the orthopaedic surgery service between July 1, 2011, and June 30, 2012. INTERVENTION: Laboratory evaluation. MAIN OUTCOME MEASUREMENTS: Metabolic and endocrine profiles included a serum analysis on all patients. Subject data included age, gender, body mass index, month of admission, and type of injury, and subjects' self-reported race, alcohol, recreational drug, and tobacco use were collected. RESULTS: Six hundred fifty-two subjects with an average age of 41.2 years were evaluated. After data analysis, only 25-hydroxyvitamin D levels were found to be persistently poor across the patient population: 86.2% of subjects were insufficient in 25-hydroxyvitamin D (<30 ng/mL), 53.2% were deficient (<20 ng/mL), and 14.0% had levels <10 ng/mL (severely deficient); 76.7% of the subjects increased skin pigmentation, and the differences in 25-hydroxyvitamin D levels between races were significantly different. African Americans had the highest risk of severe deficiency. 25-Hydroxyvitamin D levels were significantly higher during summer months, with men, and with a lower body mass index, but there were no differences based on age or substance use. Additional laboratory analysis did not reveal significant nutritional deficiency. CONCLUSIONS: The prevalence of hypovitaminosis D is widespread. This may negatively affect outcomes for orthopaedic patients but would be easily correctable. 25-Hydroxyvitamin D serologic analysis should be considered for all orthopaedic trauma patients. LEVEL OF EVIDENCE: Prognostic Level IV. See Instructions for Authors for a complete description of levels of evidence.
