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Clostridium difficile is an important cause of nosocomial acquired antibiotic-associated diarrhea causing an estimated 453,000 cases with 29,000 deaths yearly in the U.S. Both antibiotic resistance and toxin expression of C. difficile correlate with the severity of C. difficile infection (CDI). In this report, a total of 139 C. difficile isolates from patients diagnosed with CDI in Tampa General Hospital (Florida) in 2016 were studied for antibiotic resistance profiles of 12 types of antibiotics and toxin production. Antibiotic resistance determined by broth microdilution method showed that strains resistant to multi-antibiotics are common. Six strains (4.32%) showed resistance to six types of antibiotics. Twenty strains (14.39%) showed resistance to five types of antibiotics. Seventeen strains (12.24%) showed resistance to four types of antibiotics. Thirty-nine strains (28.06%) showed resistance to three types of antibiotic. Thirty-four strains (24.46%) showed resistance to two types of antibiotics. While, all isolates were susceptible to metronidazole, and rifaximin, we found that one isolate (0.72%) displayed resistance to vancomycin (MIC ≥ 8μg/ml), and another one was resistant to fidaxomicin (MIC >1μg/ml). The percentage of isolates resistant to cefoxitin, ceftriaxone, chloramphenicol, ampicillin, clindamycin, erythromycin, gatifloxacin, and moxifloxacin was 75.54, 10.79, 5.76, 67.63, 82.70, 45.32, 28.06, and 28.78%, respectively. Toxin profiling by PCR showed the isolates include 101 (72.66%) A+B+CDT-strains, 23 (16.55%) A+B+CDT+ strains, 3 (2.16%) A-B+CDT+ strains, 1 (0.72%) A-B+CDT-strains, and 11 (7.91%) A-B-CDT-strains. Toxin production determined by ELISA using supernatants of bacterial culture harvested at 12, 24, 48, and 72 h of post inoculation (hpi) showed that the toxins were mainly produced between 48 and 72 hpi, and toxin B (TcdB) was produced faster than toxin A (TcdA) during the experimental time (72 hpi). In addition, the binary-positive strains were likely to yield more toxins compared to the binary-negative strains. This work contributes to the current understanding of the antibiotic resistance and virulence of C. difficile clinical strains. [ABSTRACT FROM AUTHOR]

Background: Physicians rely on blood culture to diagnose bloodstream infections (BSI) despite its limitations. As new technologies emerge for rapid BSI diagnosis, optimization of their application to patient care requires an understanding of clinicians’ perspectives on BSI diagnosis and how a rapid test would influence medical decisions. Methods: We administered a 26-question survey to practitioners in infectious diseases/microbiology, critical care, internal medicine, and hematology/oncology services in USA and Germany about current standards in diagnosing and treating BSI and a hypothetical rapid BSI test. Results: Responses from 242 providers had roughly equal representation across specialties. For suspected BSI patients, 78% of practitioners would administer empiric broad spectrum antibiotics although they estimated, on average, that 31% of patients received incorrect antibiotics while awaiting blood culture results. The ability of blood culture to rule in or rule out infection was very/extremely acceptable in 67% and 36%, respectively. Given rapid test results, 60–87% of practitioners would narrow the spectrum of antimicrobial therapy depending on the microorganism detected, with significantly higher percentages when resistance determinants were also tested. Over half of respondents felt a rapid test would be very/extremely influential on clinical practice. Conclusions: Limitations of blood culture were perceived as a barrier to patient care. A rapid test to diagnose BSI would impact clinical practice, but the extent of impact may be limited by prevailing attitudes and practices. Opportunities exist for interventions to influence practitioners’ behaviors in BSI management particularly with emergence of newer diagnostic tests. [ABSTRACT FROM AUTHOR]

Background Nocardia species can cause localized or disseminated disease in humans. Infection results from direct inoculation or inhalation. In recent years, several new species have been identified via molecular methods. Further speciation is crucial as each organism has its own spectrum of disease and unique antibiotic susceptibility patterns. Immunosuppression, alcoholism, and certain lung diseases are well-established risk factors for nocardiosis. In fact, cases have incremented in association with increasing population of immunocompromised hosts as well as improved methods for detection and identification. Thus, Nocardia species may be considered opportunistic pathogens. Nocardia bejingensis was first isolated in 2001 by Wang et al from sewage soil in China. The first human infections were reported in Asia. Subsequently, cases were reported in Europe and a few cases have been described in the United States but it has been infrequently cited in the literature. Thus, not much is known about its spectrum of disease. Methods The primary objective of this study was to determine the risk factors and clinical manifestations of Nocardia bejingensis infection via retrospective chart review of 6 cases identified in Tampa General Hospital and Moffitt Cancer Center within a 5-year period. We aimed to evaluate the treatment used and the antibiotic susceptibility patterns of the isolates. Results All patients were immunocompromised (1/3 HIV/AIDS, 1/3 hematologic malignancy, 1/3 solid-organ transplant). Most were male (67%) and mean age of 48. The majority had lung involvement (67%). Thecal sac infection and femur osteomyelitis (OM) were atypical manifestations. Localized disease predominated. Combination therapy was preferred. Trimethoprim-sulfamethoxazole (TMP-SMX), Ceftriaxone, and carbapenems were mostly used. All isolates were susceptible to TMP-SMX. See Table 1. Conclusion This case series depicts clinical features, risk factors, and epidemiology of Nocardia bejingensis infections. Our observations suggest that it is a novel pathogen in the United States, affecting mainly immunocompromised hosts. Early detection, appropriate antibiotics, and surgery were keys in successful management. However, further studies are needed to further elucidate its pathogenesis. Disclosures All authors: No reported disclosures. [ABSTRACT FROM AUTHOR]