bAcinetobacter baumannii frequently causes nosocomial infections and outbreaks. Whole-genome sequencing (WGS) is a promising technique for strain typing and outbreak investigations. We compared the performance of conventional methods with WGS for strain typing clinical Acinetobacter isolates and analyzing a carbapenem-resistant A. baumannii (CRAB) outbreak. We performed two band-based typing techniques (pulsed-field gel electrophoresis and repetitive extragenic palindromic-PCR), multilocus sequence type (MLST) analysis, and WGS on 148 Acinetobacter calcoaceticus-A. baumannii complex bloodstream isolates collected from a single hospital from 2005 to 2012. Phylogenetic trees inferred from core-genome single nucleotide polymorphisms (SNPs) confirmed three Acinetobacter species within this collection. Four major A. baumannii clonal lineages (as defined by MLST) circulated during the study, three of which are globally distributed and one of which is novel. WGS indicated that a threshold of 2,500 core SNPs accurately distinguished A. baumannii isolates from different clonal lineages. The bandbased techniques performed poorly in assigning isolates to clonal lineages and exhibited little agreement with sequence-based techniques. After applying WGS to a CRAB outbreak that occurred during the study, we identified a threshold of 2.5 core SNPs that distinguished nonoutbreak from outbreak strains. WGS was more discriminatory than the band-based techniques and was used to construct a more accurate transmission map that resolved many of the plausible transmission routes suggested by epidemiologic links. Our study demonstrates that WGS is superior to conventional techniques for A. baumannii strain typing and outbreak analysis. These findings support the incorporation of WGS into health care infection prevention efforts.A n important role of clinical microbiology is to identify relationships between bacterial isolates. At a broad level, phenotypic and genotypic tests are used to categorize bacterial isolates into the same or different species. Within a bacterial species, techniques are used to group isolates into clonal lineages, which are groups of closely related bacteria that share a recent common ancestor but have spread regionally or globally. At a more local level, infection control practitioners must determine whether a group of isolates constitutes a hospital outbreak by ascertaining whether the isolates have a degree of similarity consistent with a common source within the hospital. Once isolates belonging to a hospital outbreak have been identified, similarities and differences between these isolates can be exploited to generate a transmission map to aid in finding the source of the outbreak and in disrupting ongoing pathways of transmission. For some groups of bacteria, such as Acinetobacter, discernment at each level has medically important consequences and therefore must be accomplished by hospital-associated clinical microbiology laboratories.Within the Acinetobacter genus, the Acinetobacter calcoaceticusAcinetobac...

SUMMARY The creatine in packed red cells was estimated by the diacetyl‐i‐naphthol technique. The error due to the presence of other guanidino compounds in the cells was found to be small. The mean value for creatine in the packed red cells of normal females was found to be 5.6 (S.D. ± 1.3) mg. per 100 ml., and in normal males 4.4 (S.D. ± 1.5) mg. per 100 ml. The sex difference is statistically significant. When red cells were segregated according to age by centrifugation the young red cells contained more creatine than the old cells. The creatine in the mixed population of red cells of patients under treatment for anaemia in whom there was increased erythropoiesis was greatly elevated; values as high as 50 mg. per 100 ml. were observed. With a decline in marrow activity and reticulocytosis there was a persistence of the high red‐cell creatine for a long time, suggesting that the loss of creatine from the cells with age is a gradual process. It is concluded that the level of creatine in the circulating red cells is a sensitive parameter of the mean age of the population.

Most guidelines for pre-transplant screening recommend enhanced screening among patients with potential exposure to such pathogens as Strongyloides stercoralis and Trypanosoma cruzi, the cause of Chagas disease. The incidence of these diseases in the Hispanic immigrant population has not been extensively studied. Transplant candidates who were evaluated by our program's Hispanic Transplant Program were referred for expanded infectious disease screening including Mycobacterium tuberculosis, S. stercoralis, Leishmania, and T. cruzi. Between December 2006 and December 2008, 83 patients were screened. Most were from Mexico but we also screened patients from Ecuador, Puerto Rico, and Peru. Most patients lived in urban locations before moving to the United States. Latent tuberculosis infection (LTBI) was found in 20%, and 6.7% had serologic evidence of S. stercoralis infection. These patients underwent treatment of latent infection without difficulty. To date, 14 patients have undergone living-donor kidney transplantation. Two of these patients had positive Leishmania titers and are being followed clinically, 1 was treated for S. stercoralis, and 2 were treated for LTBI pre-transplant. All have done well without evidence of screened pathogens an average of 348 days (range 65-766 days) post transplant. Expanded screening identifies endemic infections in the Hispanic immigrant population that can be treated before transplant, thereby minimizing post-transplant infectious complications.

Summary Objectives Bacteria within the Acinetobacter calcoaceticus-Acinetobacter baumannii (ACB) complex commonly cause nosocomial infection and are often multidrug resistant. Advances in genospecies typing allow for speciation within the ACB complex; however, little is known about the effect of genospecies on patient outcomes. Methods Adult patients with ACB complex bacteremia from Jan 2005–Oct 2012 were included. Bacterial isolates were speciated by rpoB gene sequence analysis, and clinical data were collected. Results Of 147 patients with ACB complex bacteremia, 116 had A. baumannii (78.9%), 28 had A. pittii (19.0%), and 3 had A. nosocomialis (2.0%). A. baumannii bacteremia was associated with greater comorbidity and was more frequently multidrug resistant (79% vs. 16%, p < 0.01). Multidrug resistant A. baumannii but not susceptible A. baumannii was associated with worse outcomes compared to non-baumannii ACB complex bacteremia. Neither multidrug resistance nor genospecies was an independent predictor of mortality, but receipt of appropriate therapy was associated with decreased risk of mortality (OR, 0.13; 95% CI, 0.04–0.44; p < 0.01). Conclusions A. baumannii bacteremia is associated with worse clinical outcomes than non-baumannii ACB complex bacteremia. The difference, however, appears to be related to multidrug resistance and attendant receipt of appropriate therapy rather than genospecies.

BackgroundGuidelines for antibiotics prior to dental procedures for patients with specific cardiac conditions and prosthetic joints have changed, reducing indications for antibiotic prophylaxis. In addition to guidelines focused on patient comorbidities, systematic reviews specific to dental extractions and implants support preprocedure antibiotics for all patients. However, data on dentist adherence to these recommendations are scarce.MethodsThis was a cross-sectional study of veterans undergoing tooth extractions, dental implants, and periodontal procedures. Patients receiving antibiotics for oral or nonoral infections were excluded. Data were collected through manual review of the health record.ResultsOf 183 veterans (mean age, 62 years; 94.5% male) undergoing the included procedures, 82.5% received antibiotic prophylaxis (mean duration, 7.1 ± 1.6 days). Amoxicillin (71.3% of antibiotics) and clindamycin (23.8%) were prescribed most frequently; 44.7% of patients prescribed clindamycin were not labeled as penicillin allergic. Of those who received prophylaxis, 92.1% received postprocedure antibiotics only, 2.6% received preprocedural antibiotics only, and 5.3% received pre- and postprocedure antibiotics. When prophylaxis was indicated, 87.3% of patients received an antibiotic. However, 84.9% received postprocedure antibiotics when preprocedure administration was indicated. While the majority of antibiotics were indicated, only 8.2% of patients received antibiotics appropriately. The primary reason was secondary to prolonged duration. Three months postprocedure, there were no occurrences of Clostridium difficile infection, infective endocarditis, prosthetic joint infections, or postprocedure oral infections.ConclusionThe majority of patients undergoing a dental procedure received antibiotic prophylaxis as indicated. Although patients for whom antibiotic prophylaxis was indicated should have received a single preprocedure dose, most antibiotics were prescribed postprocedure. Dental stewardship efforts should ensure appropriate antibiotic timing, indication, and duration.

GNB are isolated frequently in Veterans with SCI/D and have demonstrated increasing resistance over the past 9 years. Priority should be given to controlling the spread of resistant bacteria in this population. Knowledge of local and regional epidemiologic trends in antibiotic resistance in patients with SCI/D may improve appropriate antibiotic prescribing.

BackgroundGuidelines for dental procedure antibiotic prophylaxis have changed significantly, reducing the number of patients indicated to receive antibiotics. The primary objective was to determine the frequency and appropriateness of dental antibiotic prophylaxis at a VA dental clinic.MethodsThis was a cross-sectional study of patients undergoing tooth extractions, dental implants and periodontal procedures in 2015. These procedures are among the most common procedures with the potential for bacteremia post-dental procedure. Patients receiving antibiotics for a separate oral or non-oral infection on the date of the dental procedure were excluded.ResultsOf 183 Veterans undergoing the included dental procedures, 82.5% received antibiotic prophylaxis. Amoxicillin (71.3% of antibiotics) and clindamycin (23.8%) were prescribed most frequently; 44.7% of clindamycin was prescribed to patients not labeled as penicillin allergic. The mean duration of antibiotics was 7.1 +/- 1.6 (1–14) days; 82.5% receiving seven days supply. Of those that received antibiotic prophylaxis, 92.1% received post-procedure antibiotics only, 2.6% pre-procedural antibiotics only and 5.3% received pre- and post-procedure antibiotics. When prophylaxis was indicated (procedure and/or cardiac condition), 85.3% received an antibiotic. However, 72.7% received post-procedure antibiotics when only pre-procedure administration was indicated. When pre-procedure antibiotics were indicated, 11.5% did not receive any antibiotics (pre- or post-procedure). Only 8.2% received antibiotics appropriately based on administration time, procedure and co-morbidities. Three months post-procedure, there were no occurrences of Clostridium difficile, infective endocarditis, prosthetic joint infections or oral infections.ConclusionThe majority of patients undergoing a dental procedure received antibiotic prophylaxis. While the majority of these antibiotics were indicated pre-procedure, prescribing of post-procedure antibiotic for excessive durations was frequent. Dental stewardship efforts should ensure appropriate timing, indications, and duration of antibiotic prophylaxis.Disclosures All authors: No reported disclosures.

OBJECTIVES To describe the burden of extended-spectrum β-lactamase (ESBL) Enterobacteriaceae in veterans with spinal cord injury or disorder (SCI/D), to identify risk factors for ESBL acquisition, and to assess impact on clinical outcomes DESIGN Retrospective case-case-control study PATIENTS AND SETTING Veterans with SCI/D and utilization at a Veterans' Affairs medical center from January 1, 2012, to December 31, 2013. METHODS Patients with a positive culture for ESBL Klebsiella pneumoniae, Escherichia coli, or Proteus mirabilis were matched with patients with non-ESBL organisms by organism, facility, and level of care and to uninfected controls by facility and level of care. Inpatients were also matched by time at risk. Univariate and multivariate matched models were assessed for differences in risk factors and outcomes. RESULTS A total of 492 cases (62.6% outpatients) were matched 1:1 with each comparison group. Recent prior use of fluoroquinolones and prior use of third- and fourth-generation cephalosporins were independently associated with ESBL compared to the non-ESBL group (adjusted odds ratio [aOR], 2.61; 95% confidence interval [CI], 1.77-3.84; P<.001 for fluoroquinolones and aOR, 3.86; 95% CI, 2.06-7.25; P<.001 for third- and fourth-generation cephalosporins) and the control group (aOR, 2.10; 95% CI, 1.29-3.43; P = .003 for fluoroquinolones; and aOR, 3.31; 95% CI, 1.56-7.06; P=.002 for third- and fourth-generation cephalosporins). Although there were no differences in mortality rate, the ESBL group had a longer post-culture length of stay (LOS) than the non-ESBL group (incidence rate ratio, 1.36; 95% CI, 1.13-1.63; P=.001). CONCLUSIONS All SCI/D patients with ESBL were more likely to have had recent exposure to fluoroquinolones or third- and fourth-generation cephalosporins, and hospitalized patients were more likely to have increased post-culture LOS. Programs targeted toward reduced antibiotic use in SCI/D patients may prevent subsequent ESBL acquisition. Infect Control Hosp Epidemiol 2016;37:768-776.