316. Application of New Consensus Definition Identifies High Numbers of Fracture Related Infections with Negative Cultures

Background Fracture related infection (FRI) is a severe complication in trauma surgery but defining the full impact of these infections has been challenging with the lack of clear diagnostic criteria. This is particularly problematic for culture-negative FRI (CNFRI), which lack pathogen identification to guide antimicrobial therapy. However, new consensus definition and criteria for the diagnosis of FRI (Table) may help reduce the risk of diagnostic error. The purpose of this study was to determine the proportion and clinical characteristics of CNFRI cases at a level I trauma hospital using the new diagnostic criteria. Methods Laboratory reports were used to identify all patients with at least one specimen submitted for microbiology culture by an orthopedic surgeon at our trauma I level hospital in Cincinnati, Ohio during a three-year study period. This cohort was refined by an electronic medical record (EMR) review to select patients that met the diagnostic criteria for suspected/confirmed FRI. The specimen details and results of the cultures were recorded for the first orthopedic surgeon collection for each suspected FRI case. Clinical data, including fracture characteristics, surgical treatment, antibiotic utilization, and patient outcomes were also extracted from the EMR for each case. Results A total of 246 patients were identified with at least one culture specimen; 35.8% (n = 88) of these were deemed suspected/confirmed FRI based on consensus guidelines. The cultures for the first orthopedic surgery collection on these FRI were negative for 35% (n = 31). The most common location for CNFRI were proximal lower extremity fractures (52%), a distribution different from that of culture positive (Figure). Culture positive FRI were predominated by Staphylococcus aureus (39%) followed by gram negative rods (23%). Conclusion This retrospective cohort study identified a sizable proportion of CNFRI at our trauma center using the recently published consensus definition. While further analysis is necessary to determine the exact impact of these new criteria, this suggests that clearer definitions may facilitate improved recognition of CNFRI. Because of the relatively high rates of CNFRI, efforts to standardize laboratory diagnostic processes and case management will be required. Disclosures Henry C. Sagi, MD, FACS, Conexxions (Board Member)GLW trauma (Consultant)GLW trauma (Shareholder)Stryker (Consultant)

A Statistically Significant Reduction in Hospital Onset Clostridioides difficile Events Using a Learning Collaborative Model

Background: Evidence-based best practices are available for the reduction and prevention of Clostridioides difficile infection (CDI). Often, these practices are not consistently followed in many inpatient care settings. A learning collaborative model resulted in a cost neutral, rapid, sustainable, statistically significant reduction in CDI events across an 88-hospital campus system without requiring hospitals to standardize laboratory methods, increase spending or increase staffing. Methods: In March 2018, a healthcare system with 88 critical access and community hospital campuses across 29 states participated in a harms-reduction learning collaborative. The collaborative format included educational webinars, gap analyses, action plans, and coaching calls facilitated by subject matter experts (SMEs). A collaborative cohort of 11 hospitals (55% rural*) was identified as having significant opportunity for improvement. These facilities participated in 3 monthly coaching calls. The coaching calls supported peer-to-peer sharing of practices and discussions of challenges and successes, and educational materials and presentations were provided by SMEs in pharmacy and infection prevention. Results: Statistically significant changes for the 88-hospital system as a whole: (1) 2018 compared to 2017: P < .001 (statistically significant); (2) 1H2018 compared to 2H2018 (before-and-after collaborative): P = .001; (3) 2019 compared to 2018: P < .001 (statistically significant). Statistically significant changes for the collaborative cohort: (1) 2018 compared to 2017: P < .001; (2) 1H2018 compared to 2H2018 (before-and-after collaborative): P = .002; and (3) 2019 compared to 2018: P < .001. We used 2-proportion, 2-tailed z-test for our analysis. Conclusions: Utilizing a learning collaborative model that included webinars, gap analyses, and interactive coaching calls, a cohort of 11 hospitals was able to induce rapid improvements to adherence of evidence-based practices resulting in a rapid, sustained, statistically significant improvement for both the cohort hospitals and the healthcare system.*2018 American community survey, US Census.Funding: NoneDisclosures: None

Implementation of a Standardized Prenatal Testing Protocol in an Integrated, Multihospital Health System

Objectives When our institution grew into an integrated multihospital health system, we were faced with the need to standardize laboratory processes, including blood bank processes, across all locations. The purpose of this article is to describe our experience of standardizing the protocols for prenatal testing. Methods For each hospital in the system, we established service tiers to define tests offered on site or referred to another location. For each prenatal test, we examined the related processes for ways to improve uniformity, efficiency, and reliability. Throughout this process of standardization, we collaborated with the clinical services to gain concurrence on the interpretation and reporting of results. Results We created and implemented a uniform protocol for testing prenatal patients. The protocol standardized the definition of critical titer, instituted criteria to identify passively acquired anti-D, and established a process for the follow-up of women with inconsistent serologic results on Rh(D) typing. Conclusions Close collaboration with the clinical services ensured that our testing protocol is aligned with the needs of the integrated obstetrics service in the health system. The approach described in this article may provide a plan outline for pathologists facing similar challenges at other integrated health systems.

2. Investigating crime

‘Investigating crime’ explains how the police investigate criminal activity, setting out some of the principles and procedures involved and how forensic science provides them with answers. Radical changes in English law and forensic science practices resulted in the introduction of formal quality assurance systems to standardize laboratory practices and the Police and Criminal Evidence Act (1984), which specifies how police deal with accused persons, go about their investigations, and are accountable for their actions. The ‘trace, interview, eliminate’ (TIE) method of systematic elimination of individuals from an investigation is described, as well as the role of digital forensics to extract and interpret data from a wide range of devices.

Clostridium difficile Infections in Children: Impact of the Diagnostic Method on Infection Rates

BACKGROUNDPolymerase chain reaction (PCR) assays based on the detection of the toxin B gene are replacing enzyme-linked immunosorbent assay (ELISA)–based toxin production detection or cell cytotoxicity assay in most laboratories.OBJECTIVETo determine the proportion of pediatric patients diagnosed withClostridium difficile infection by PCR who would have also been diagnosed by ELISA and to compare the clinical characteristics of PCR+/ELISA+ vs PCR+/ELISA− patients.METHODSUsing the microbiology laboratory information system, stool samples positive for C. difficile by PCR between October 2010 and July 2014 were identified. Using frozen stool specimens, an ELISA for toxin A and B was performed. A retrospective medical chart review was conducted to obtain demographic and clinical data. Duplicate samples were excluded.RESULTSA total of 136 PCR-positive samples underwent ELISA testing: 54 (40%) were positive for toxin A or B. The mean (SD) age of the entire cohort was 8.5 (6.2) years. There was no difference in age, gender, clinical manifestation, previous medical problems, and management between patients positive or negative by ELISA. However, patients positive by ELISA were more likely to have had a recent exposure to antibiotics (67.9% vs 50%; crude odds ratio, 2.1 [95% CI, 1.03–4.28]).CONCLUSIONIn our pediatric population, 60% of patients with C. difficile diagnosed by PCR had no toxin detectable by ELISA. ELISA-negative patients were less likely to have received an antibiotic recently compared with ELISA-positive patients. These results highlight the need to standardize laboratory criteria for the diagnosis of C. difficile infections in children.Infect Control Hosp Epidemiol 2016;37:1087–1093

Semen analysis

Semen analysis remains the most important diagnostic tool for the study of male infertility to date. For this reason, and because of the ease of carrying out this analysis, examination of seminal fluid should be among the first diagnostic steps in cases of suspected infertility, prior to subjecting the man’s partner to long and complex diagnostic tests. The efficacy of an examination of seminal fluid depends on the experience and ability of the seminologist, who must first undertake a subjective analysis of fundamental parameters such as motility and morphology. Moreover, laboratories specialized in such analyses may apply different criteria to the evaluation of sperm parameters, making it extremely difficult to compare tests carried out in different laboratories (1). In an attempt to resolve these problems of inconsistency, and in order to standardize laboratory techniques, a committee of experts from the WHO established guidelines for semen analysis in 1980 (an updated version was published in 1999) (2). In recent years, numerous other methods of semen analysis capable of providing in-depth diagnostic information on the fertilising capacity of spermatozoa have become available. The computer-aided sperm analysis (CASA) system is a technique for sperm analysis designed to provide objective data on sperm motility (3). Because of persisting difficulties in software set-up (4), it should not be used for routine analysis, but rather as a research tool. At the same time, significant advances have been made in the study of sperm morphology through the use of scanning and transmission electron microscopes (5). Finally, within the past decade several tests capable of evaluating the integrity of sperm components, such as the membrane, acrosome, DNA, and nuclear protein, have been developed and put into use. These more complex and costly analytical tools should be considered of secondary or tertiary importance, and are to be carried out in specific cases only after standard semen analysis. Standard semen analysis remains the first and fundamental diagnostic tool.

A COMPARISON AMONG NINE CANADIAN LABORATORIES OF DITHIONITE-, OXALATE-, AND PYROPHOSPHATE-EXTRACTABLE Fe AND Al IN SOILS

The results of two studies are reported: (1) a comparison of colorimetric and atomic absorption measurements of Fe and Al in dithionite, oxalate, and pyrophosphate extracts of soils; and (2) a comparison among nine Canadian laboratories of measurements of dithionite-, oxalate-, and pyrophosphate-extractable Fe and Al in six soils. Colorimetric and atomic absorption analyses gave the same measurements of Fe and Al in dithionite, oxalate, and pyrophosphate extracts of soils. Data reported by six Canadian laboratories showed close agreement; data reported by three laboratories showed poor agreement, indicating a need for reference soil samples containing known amounts of extractable Fe and Al to standardize laboratory procedures. Atomic absorption analysis of the extracts is much more rapid than colorimetric analysis and details of the atomic absorption methods are appended.