Abstract
The Verigene Clostridium Difficile Nucl. Acid Test Is A Multiplex Qualitative PCR Assay That Utilizes A Nanoparticle-based Array Hybridization Method to Detect C. Difficile TcdA and TcdB in Fecal Specimens. in Addition, the Assay Detects Binary Toxin Gene Sequences and the Single Base Pair Deletion at Nucleotide 117 in TcdC to Provide A Presumptive Identification of the Epidem. Strain 027/NAP1/BI . This Stud. Compared the Verigene CDF Test with Anaerobic Direct and Enriched Toxigenic Culture on Stool Specimens from Symptomatic Patients among Five Geographically Diverse Labs. Within the U. States. the Verigene CDF Test Was Performed Acc. to the Manufacturer's Instructions, and the Ref. Methods Performed by A Ctrl. Lab. Included Direct Culture onto Cycloserine Cefoxitin Fructose Agar and Enriched Culture Using Cycloserine Cefoxitin Mannitol Broth with Taurocholate and Lysozyme. Recovered Isolates Were Identified As C. Difficile Using Gas Liquid Chrom. and Were Tested for Toxin Using A Cell Culture Cytotoxicity Neutralization Assay. Strains Belonging to Ribotype 027 Were Determined by PCR Ribotyping and Bidirectional Sequencing for 117 in TcdC. A Total of 1,875 Specimens Were Evaluable. of These, 275 Specimens Were Culture Positive by Either Direct or Enriched Culture Methods. Compared to Direct Culture Alone, the Overall Sensitivity, Specificity, Positive Predictive Value, and Negative Predictive Value for the Verigene CDF Test Were 98.7%, 87.5%, 42%, and 99.9%, Respectively. Compared to Comb. Direct and Enriched Culture Results, the Sensitivity, Specificity, Positive Predictive Value, and Negative Predictive Values of the Verigene CDF Test Were 90.9%, 92.5%, 67.6%, and 98.3%, Respectively. of the 250 Concordantly Culture-positive Specimens, 59 Were Flagged As "Hypervirulent"; 53 Were Confirmed As Ribotype 027, and All 59 Possessed 117 in TcdC. Time to Results Was Approx. 2.5 H per Specimen. the Verigene CDF Test Is A Novel Nucl. Acid Microarray That Reliably Detects Both C. Difficile Toxins A and B in Unformed Stool Specimens and Appears to Adequately Identify Ribotype 027 Isolates.