PCR Based Fecal Pathogen Panel Testing Should Be Interpreted with Caution at Diagnosis of Pediatric Inflammatory...

Area of Science:

• Pediatric Gastroenterology
• Clinical Microbiology
• Diagnostic Testing

Background:

• Chronic diarrhea in children is a common concern, with pediatric inflammatory bowel disease (IBD) being a key differential diagnosis.
• Stool studies, including bacterial culture, are standard for identifying infectious causes of diarrhea.
• Molecular diagnostic techniques, such as multiplex PCR panels, are increasingly used for detecting enteric pathogens due to their high sensitivity.

Observation:

• Two cases of pediatric inflammatory bowel disease (IBD) presented with chronic diarrhea and positive results on multiplex PCR panels for enteric pathogens.
• In one case, positive PCR results for an enteric pathogen potentially delayed the diagnosis of IBD.
• In the second case, positive PCR results were disregarded without adverse clinical impact.

Findings:

• Multiplex PCR panels can detect a wide range of enteric pathogens with high sensitivity.
• The clinical significance of positive molecular test results for enteric pathogens in the context of suspected IBD is not always clear.
• In pediatric patients with symptoms suggestive of IBD, positive PCR results alone should not preclude or delay endoscopic evaluation, particularly when parallel stool cultures are negative.

Implications:

• Over-reliance on molecular testing for enteric pathogens may lead to misdiagnosis or delayed diagnosis of pediatric IBD.
• Clinical correlation and consideration of alternative diagnoses, such as IBD, are essential when interpreting molecular diagnostic results in children with chronic diarrhea.
• Endoscopic evaluation remains a critical diagnostic tool for children with suspected IBD, irrespective of molecular pathogen detection results.