Work

Tests for Inflammation (Stool and Blood) and Stool Spore Density Correlate Better With Clostridium difficile Infection (CDI) (tcdB and Toxin Positive Samples) Than the Number of Stools per Day

Year: 2016

Type: article

Abstract: Background. Distinguishing between C. difficile colonization versus infection (CDI) is difficult and requires a combination of laboratory tests and clinical criteria. PCR is a highly sensitive test that is commonly used to diagnose toxigenic CDI. However, results from several recent studies raise the question of whether PCR is overly sensitive. Our hypothesis was that selected laboratory tests could be used to distinguish between colonized and infected patients who were PCR positive for toxigenic C. difficile. Methods. Patients that submitted an unformed stool sample for CDI testing between 1 October 2012 and 30 September 2013 and had a positive test by PCR (Cepheid) were included in the study. Interviews were conducted for the number of stools per day (BM/D) and charts were reviewed for relevant clinical data. Stool samples were sent frozen to TechLab for additional testing including cell cytotoxicity for TcdB, quantitative toxigenic bacterial culture, PCR-ribotyping, and quantitative fecal lactoferrin and glutamate dehydrogenase (GDH) by immunoassay. Results. A total of 215 PCR-positive patients were included with a mean age of 71 years. Stools per day separated patients into groups with <3 BM/D (26%), 3 to 10 BM/D (57%), and >10 BM/D (17%). Further testing showed that 55% of patients were cell cytotoxicity positive and 90% were toxigenic culture positive. Spore counts ranged from 102 to 108 CFU/g stool. Ribotype 027 was detected in 23% of patients. Stool toxin-positive patients had lower Ct (p = 1 x 10−19), higher WBC (p = 1 x 10−6), higher counts (p = 1.8 x 10−16), more lactoferrin (p = 1 x 10−6), and higher GDH concentrations (p = 4.6 x 10−18). Interestingly, the number of stools per day did not correlate with microbiological or clinical indicators of CDI even when patients on a laxative and antidiarrheal (50%) agents were removed. Conclusion. Patients who had lower Ct, higher spore counts, and positive stool toxin by cell cytotoxicity were associated with significantly increased levels of fecal lactoferrin and blood WBC; however, the number of stools per day did not correlate with worse inflammatory markers. Additional studies are needed to both determine the utility of stools per day as a criteria in diagnosing CDI and also determine if these markers can help define clinical CDI. Disclosures. J. Boone, TechLab: Employee, Salary; R. Carman, TechLab: Employee, Salary; D. Persing, Cepheid: Employee, Salary

Source: Open Forum Infectious Diseases

DOI: 10.1093/ofid/ofw172.1629

Authors: James Boone, Becky Smith, Robert Carman, David Persing, Lance Peterson

Institutions: TechLab (United States), University of Chicago, Cepheid (United States)

Language: English

Topic: Clostridium difficile and Clostridium perfringens research

Subfield: Infectious Diseases

Field: Medicine

Domain: Health Sciences

SDG: Good health and well-being

Open Access status: gold

Estimated APC paid: $4,053