Clostridium difficile Infections in Children: Impact of the Diagnostic Method on Infection Rates

Abstract

BACKGROUNDPolymerase chain reaction (PCR) assays based on the detection of the toxin B gene are replacing enzyme-linked immunosorbent assay (ELISA)–based toxin production detection or cell cytotoxicity assay in most laboratories.OBJECTIVETo determine the proportion of pediatric patients diagnosed withClostridium difficile infection by PCR who would have also been diagnosed by ELISA and to compare the clinical characteristics of PCR+/ELISA+ vs PCR+/ELISA− patients.METHODSUsing the microbiology laboratory information system, stool samples positive for C. difficile by PCR between October 2010 and July 2014 were identified. Using frozen stool specimens, an ELISA for toxin A and B was performed. A retrospective medical chart review was conducted to obtain demographic and clinical data. Duplicate samples were excluded.RESULTSA total of 136 PCR-positive samples underwent ELISA testing: 54 (40%) were positive for toxin A or B. The mean (SD) age of the entire cohort was 8.5 (6.2) years. There was no difference in age, gender, clinical manifestation, previous medical problems, and management between patients positive or negative by ELISA. However, patients positive by ELISA were more likely to have had a recent exposure to antibiotics (67.9% vs 50%; crude odds ratio, 2.1 [95% CI, 1.03–4.28]).CONCLUSIONIn our pediatric population, 60% of patients with C. difficile diagnosed by PCR had no toxin detectable by ELISA. ELISA-negative patients were less likely to have received an antibiotic recently compared with ELISA-positive patients. These results highlight the need to standardize laboratory criteria for the diagnosis of C. difficile infections in children.Infect Control Hosp Epidemiol 2016;37:1087–1093

Epidemiology of Clostridioides difficile infection in Canada: A six-year review to support vaccine decision-making

“…The introduction of more sensitive laboratory testing methods, such as polymerase chain reaction, which detects the toxigenic potential but not the actual toxin production, has been associated with increasing numbers of positive tests and earlier detection compared with enzyme-linked immunosorbent assay (23,24). Currently, although all the provinces required clinical validation for the identification of CDI cases, the test methods used for this validation varied.…”

Transmission of Clostridioides difficile infection (CDI) from patients less than 3 years of age in a pediatric oncology setting

“…14 In recent years CDI is increasingly been diagnosed among children <3 years old in oncology settings, largely due to the widespread use of highly sensitive molecular diagnostic methods. 6,15 Differentiating true disease from colonization can be especially challenging in younger children, particularly if adult criteria are used to define disease severity in pediatric cases. 16 The high frequency of symptomatic or asymptomatic C. difficile carriage in the very young posits a unique nosocomial threat to older susceptible children admitted to the same pediatric unit.…”

“…Unnecessary clinical testing in this age group is a valid concern; it could lead to overrepresentation of disease burden in a population with high colonization prevalence and frequent occurrence of loose stools (strong recommendation with a moderate level of evidence). 6,7 The basis of current Infectious Disease Society of America (IDSA) recommendations originate from single-center research studies in general pediatric populations. 5,8 Although the need for treatment in patients <3 years old who test positive for toxigenic CD may not be routinely necessary, the question remains: Do these patients represent an unappreciated source of transmission to others who represent a target for prevention efforts?…”