Methods: To assess likelihood of CDI misdiagnosis in low-risk children, we retrospectively compared hospital-onset healthcare facility-associated (HO-HCFA) CDIs and CA-CDIs (i.e., children who have not been hospitalized in the previous 12 weeks) diagnosed by tcdB (i.e., toxin B gene) PCR at an academic children’s hospital over a 1-year period. We additionally compared CA-CDIs with and without outpatient exposures in the previous 12 weeks. Saved tcdB-positive stools also underwent anaerobic stool culture and multiplex gastrointestinal (GI) pathogen PCR testing.
Results: 74 children with CA-CDI were compared to 25 children with HO-HCFA CDI. Children thought to have CA-CDI were more frequently < 2 years old (18% vs. 0%, p=0.034) and less likely to have antibiotic exposure in the past 30 days (26% vs. 88%, p<0.0001), proton pump inhibitor (PPI; 16% vs. 36%, p=0.036) exposure, or a gastrostomy tube (11% vs. 32%, p=0.013). Of the 74 CA-CDIs, 30 (41%) had no outpatient exposures in the previous 12 weeks. CA-CDI cases lacking recent outpatient exposures were more likely to be < 2 years old (30% vs. 9%, p=0.029) and less likely to have inflammatory bowel disease (17% vs. 48%, p<0.01), PPI exposure (0% vs. 27%, p<0.01), and C. difficile isolated by culture (71% vs. 95%, p<0.01). Only 3 children in the cohort were tested by their healthcare provider for a viral GI pathogen other than rotavirus. Among children with CA-CDI, additional multiplex PCR testing of tcdB-positive stools identified a viral GI pathogen in 26% of stools and failed to identify C. difficile among 23% of stools. Compared to stools testing positive for C. difficile using the multiplex PCR panel, stools testing negative were more likely to also test negative for C. difficile by culture (40% vs. 9%, p=0.008).
Conclusion: Many children diagnosed with CA-CDI by tcdB PCR lack classic risk factors and have discordant results when additional CDI testing methods are performed. More selective CDI testing in low-risk pediatric populations is needed to more accurately diagnose CDI and limit unnecessary CDI antibiotic treatment in children.
Cubist: Grant Investigator , Grant recipient
Alere: Investigator , Research support
S. Shulman, None
X. Zheng, None
K. Todd, None
D. N. Gerding, Sanofi Pasteur: Board Member , Consulting fee
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Merck: Board Member , Consulting fee
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Viropharma/Shire: Consultant , Consulting fee