Validation and comparison of three adenosine triphosphate luminometers for monitoring hospital surface sanitization: a Rosetta Stone for adenosine triphosphate testing.

BACKGROUND: The application of adenosine triphosphate (ATP) luminometry for monitoring sanitized hospital surfaces is an evolving infection control practice. The goal of this study is to validate and compare 3 commercially available ATP luminometry, swab, rapid-test systems for use in hospital surface sanitization testing. Regulatory agencies may consider this a point-of-care laboratory test; it is therefore imperative that validation criteria are established. METHODS: The ability of instruments to measure long-term stability of ATP dried on surfaces was determined. Dilutions of 3 species of microorganisms and a blood sample were dried onto a surface and tested. The performance characteristics of instruments were compared side-by-side for their ability to recover microorganism-derived ATP from surfaces. RESULTS: Timed studies showed that surface biologic-ATP remained detectable for 10 days. Instrument clinical sensitivity, precision, detection range, limit of detection, and linearity were determined. Swab recovery of microorganisms from surfaces varied by instrument and organism. All 3 systems detected microorganisms in the presence of disinfectants. CONCLUSION: All instruments were validated, but only 1 was verified, because of variations in performance for each system. These studies indicate that careful consideration of the technologic application and instrument performance are important criteria for the selection of an ATP monitoring system.

An investigation of an outbreak: Methicillin resistant Staphylococcus aureus colonization in an intensive care cardiac unit.

BACKGROUND: Colonization in the nares with Methicillin Resistant Staphylococcus aureus (MRSA) has been described as a risk factor for eventual MRSA infection. The objective of this report is to describe the outbreak investigation, to identify the risk factors involved, and to evaluate and recommend control measures. METHODS: This study was a retrospective observational outbreak study carried out in the Intensive Care and Cardiac Unit. Percentages of patients with positive conversions were graphically plotted out and were used to determine expected percentage of conversions versus observed. The case definition was determined to be a patient with a positive culture for MRSA from a nasal swab upon discharge or transfer from the ICCU whose initial swab on admission was negative. RESULTS: The expected number of conversions was 2% per month and the newly observed number of conversions was 6%, which was >3 standard deviations from the mean. Repetitive sequence-based PCR (rep-PCR) was performed for the microbial DNA typing, which discovered genetically identical strains. DISCUSSION: The main finding in this outbreak investigation was that the common room which housed four of these patients was contaminated with MRSA. A limitation was that some patients who would have been included in the study did not get screened at discharge and their conversion status could not be ascertained and environment cultures were not performed. Active surveillance allowed for the detection of an outbreak of MRSA colonization which led to early intervention that prevented more patients from becoming colonized. Prevention of colonization should be one of the primary goal in the prevention of MRSA.

Establishing a hospital program to improve antimicrobial use, control bacterial resistance and contain healthcare costs: the University of Louisville experience.

Antimicrobials have been used in excess for decades. As a result, antimicrobial resistance and cost have increased. In response to this growing national problem, hospital antimicrobial teams were recom-mended in 1988, but few institutions have invested in comprehensive, interdisciplinary programs. The division of infectious diseases at the University of Louisville School of Medicine was a leader in 1990 by establishing an antimicrobial team at the University of Louisville Hospital and Veterans Affairs Hospital. This manuscript reviews the activities of the antimicrobial teams to create antimicrobial guidelines, evaluate antimicrobial use, and provide feedback to physicians. It also summarizes the successful impact the teams have had on optimizing antimicrobial use in the hospital by improving compliance with the guidelines, controlling resistant organisms, and preventing escalation of antimicrobial cost over the years.

Mixed pulmonary infection with Strongyloides stercoralis and Blastomyces dermatitidis.

We report the first case of mixed pulmonary infection with Strongyloides stercoralis and Blastomyces dermatitidis. Histopathology from the lung biopsy showed structures consistent with B. dermatitidis and S. stercoralis. A parasitology exam from a bronchi alveolar lavage yielded an immature rhabditiform larva and female worm. Fungal cultures grew B. dermatitidis.