235. Diagnosis of gastrointestinal infections A one year prospective comparison of different methods
Session: Poster Abstract Session: Diagnostic Microbiology
Thursday, October 3, 2013
Room: The Moscone Center: Poster Hall C
Background: Gastrointestinal infections (GID) contribute significantly to the morbidity and mortality of hospitalized and non-hospitalized patients worldwide. Diagnostic approached range from pure clinical assessment without confirmation to testing for every imaginable pathogen.

Methods: This study was conducted to compare different diagnostic methods for the detection of GI pathogens. Samples were prospectively analyzed from May 1st 2012 to April 30th, 2013. Diagnostic approaches included clinical diagnoses, as well as conventional and molecular techniques to test for the most common bacterial (n=10), viral (n=4) and parasitic agents (n=5). Comparison was made between different methods with regard to sensitivity and specificity. In addition, hospitalized and non-hospitalized patients from the same area were compared.

Results: A total of 1,958 samples were prospectively included over the study period. Among those 47% yielded at least one GI-pathogen. C. difficile and enteropathogenic E. coli were encountered most frequently from hospitalized and non-hospitalized patients, respectively. Sensitivity and specificity of molecular methods was the highest, followed by antigen-based tests. Clinically suspected causative pathogens could only be confirmed in 54% of positive cases.

Conclusion: Sensitivity of laboratory diagnosis of GI pathogens is highly dependent on the technique used for detection. Since initial clinical suspicion was only accurate in little more than half of the positives, a stepwise increase in the number and spectrum of pathogens searched for may have a higher accuracy than the retesting of a second sample for the same initially suspected pathogen(s).

Thomas Hoppe, MD1, Marion Steinmetz1, Ute Aurbach, MD1, Udo Schallenberg, MD1 and Hilmar Wisplinghoff, MD1,2, (1)laboratory medicine cologne, Dres. Wisplinghoff & Colleagues, Cologne, Germany, (2)Institute for Medical Microbiology and Hygiene, University of Cologne, Cologne, Germany

Disclosures:

T. Hoppe, rbiopharm: Investigator, Research support

M. Steinmetz, None

U. Aurbach, None

U. Schallenberg, None

H. Wisplinghoff, Siemens: Consultant, Investigator and Speaker's Bureau, Research support and Speaker honorarium
Cepheid: Speaker's Bureau, Speaker honorarium
rbiopharm: Investigator, Research support

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