Clinical impact of a real-time PCR assay for rapid identification of staphylococcal bacteremia.

The purpose of this study was to evaluate the impact of real-time PCR reporting both on timely identification of clustered Gram-positive cocci (GPC) in blood cultures and on appropriate antibiotic treatment. This retrospective, interventional cohort study evaluated inpatients with blood cultures positive for GPC in the pre-PCR (15 January 2009 to 14 January 2010) and post-PCR (15 January 2010 to 14 January 2011) periods. Post-PCR implementation, laboratory services completed batched PCR; results other than methicillin-resistant Staphylococcus aureus (MRSA) were reported in the electronic medical record without additional interventions. The assay's sensitivity and specificity, time to identification of staphylococcal bacteremia, and clinically relevant outcomes, including time to optimal antibiotic therapy, were evaluated. Demographic information was also collected and analyzed. Sixty-eight and 58 patients with Staphylococcus aureus bacteremia from the pre- and post-PCR periods, respectively, met inclusion criteria. Similar numbers of consecutive patients with coagulase-negative staphylococci were analyzed for comparison. The time to identification was significantly reduced post-PCR implementation (mean, 13.2 h; 95% confidence interval [95% CI], 10.5 to 15.9 h; P < 0.0001). However, the time to optimal antibiotic therapy was not significantly reduced. We conclude that implementation of a PCR assay demonstrated the potential to improve appropriate antibiotic use based on clinically meaningful and statistically significant reductions in the time to microbiologic identification. However, in order to realize this potential benefit, processes must be optimized and additional interventions initiated to facilitate providers' use of the PCR result.

Hospitalists assess the causes of early hospital readmissions.

BACKGROUND: Hospital readmissions are receiving increasing attention as an indicator of health care quality and waste. Hospitalists provide a unique perspective on the underlying processes that result in acute care readmissions and the extent to which readmissions can be prevented. OBJECTIVE: The study assessed the views of hospitalists on the preventability of readmissions and the most important ways to prevent future readmissions. DESIGN AND MEASUREMENTS: A group of 17 hospitalists serving four community hospitals reviewed the details of 300 consecutive 21-day readmissions. Each used a structured data collection form to code information from inpatient and outpatient charts on patient characteristics, process measures, preventability, and potential interventions. RESULTS: Overall, 15% of readmissions were rated as overtly preventable, but with wide variation among hospitalists in their ratings of preventability. Perceptions of preventability appear to be a function of readmission timing, the similarity of diagnoses between admissions, medication issues, and the presence of certain chronic diseases (eg, chronic obstructive pulmonary disease [COPD]). Hospitalists were more likely to recommend familiar interventions under their control for a readmissions termed preventable, such as extending the initial hospital stay or addressing medications and patient education at discharge. They less often identified outpatient case management, home services, or physician nursing home visits as viable prevention strategies. CONCLUSIONS: The study points to the multifactorial nature of interventions needed to prevent readmissions, the tradeoffs between hospital length of stay and readmission, and the importance of fostering a culture of optimism and engagement to outpatient components of the health system to reduce hospital readmissions.

Raising premiums and other costs for Oregon health plan enrollees drove many to drop out.

The Oregon Health Plan was created to be a sustainable program that could weather budgetary storms without having to cut enrollees from Medicaid. A 2003 redesign of the program increased premiums, raised cost sharing, and imposed rigid premium payment deadlines for members in the "Standard" version of the program but not for members of the "Plus" version. This paper adds two years of longitudinal data to a previous study on the impacts of these changes. It shows that the redesign was a key factor driving a 77 percent disenrollment rate in the Standard program, from a high of 104,000 enrollees in February 2003 to just 24,000 by the end of the study period, November 2005. Those who were in the Standard plan when the reduced benefits and higher member costs went into effect were also nearly twice as likely to have unmet health care needs compared to those in the Plus plan. These changes underscore that in a period of economic downturn, policy makers must understand the impact of increased cost sharing on vulnerable populations.

Reliable detection of deamidated peptides from lens crystallin proteins using changes in reversed-phase elution times and parent ion masses.

Identifying deamidated peptides using low-resolution mass spectrometry is difficult because traditional database search programs cannot accurately detect modified peptides when the mass differences are only 0.984 Da. In this study, we utilized differential reversed-phase elution behavior of deamidated and corresponding unmodified peptide forms to significantly improve deamidation detection on a low-resolution LCQ ion trap instrument. We also improved the mass measurements of unmodified and deamidated peptide forms by averaging survey scans across each chromatogram peak. Tryptic digests of a series of normal (3-day old, 2-year old, 18-year old, 35-year old, and 70-year old) and cataractous (93-year old) human lens samples were used to produce large numbers of potentially deamidated peptides. The complex peptide mixtures were separated by strong cation exchange (SCX) chromatography followed by reversed-phase (RP) chromatography. Synthetic peptides were used to show that unmodified and deamidated peptides coeluted during the SCX separation and were completely resolved with the RP conditions used. Retention time shifts (RTS) and mass differences (DeltaM) of deamidated lens peptides and their corresponding unmodified forms were manually determined for the 70-year old lens sample. These values were used to assign correct or incorrect deamidation identifications from SEQUEST searches where deamidation was specified as a variable modification. Manual validation of SEQUEST identifications from synthetic peptides, 3-day old, and 70-year old samples had an overall 42% deamidation detection accuracy. Filtering SEQUEST identifications using RTS and DeltaM constraints resulted in >93% deamidation detection accuracy. An algorithm was developed to automate this method, and 72 Crystallin deamidation sites, 18 of which were not previously reported in human lens tissue, were detected.

Two-dimensional liquid chromatography study of the human whole saliva proteome.

The human whole saliva proteome was investigated using two-dimensional liquid chromatography (2-DLC). The 2-DLC study was able to identify, with high confidence, 102 proteins including most known salivary proteins (35), and a large number of common serum proteins (67). Peptides from proline-rich proteins, abundant in saliva, had unusual cleavage sites and were frequently only partially tryptic. Three proteins not previously observed in human saliva were also detected. Significantly greater numbers of identified proteins, including high molecular weight, low molecular weight, and proline-rich proteins, were found with 2-DLC compared to previously reported two-dimensional gel electrophoresis studies.