. 2025 Aug 7;87:103371. doi: 10.1016/j.eclinm.2025.103371

Table 2.

ECIL-10 Recommendations on diagnosis of CDI in adult and paediatric patients.

	Grading
Recommendation
Test for CDI only in case of compatible signs and symptoms	A II u
Screening for asymptomatic colonization is not recommended	D II u
For stool testing use diagnostic algorithms that include both toxin detection with immunoenzymatic assay (more specific for disease) and a more sensitive test for detection of toxigenic CD in accordance with ESCMID recommendations: (1) either toxin plus NAAT or (2) Glutamate Dehydrogenase (GDH) plus toxin and, if GDH positive and toxin negative, confirm with NAAT. Rectal swabs can be tested with NAAT in case of ileus	A II t u
In case of partial or absent clinical response to CDI treatment, additional testing for other pathogens should be performed and non-infectious causes of diarrhoea should be considered (see text for details)	A II t
No repeated testing is necessary in case of a negative result obtained during the previous 7 days of the same diarrhoea episode	B II t
Testing for proof of cure is not recommended	D II t
Comments on testing in children
• Testing for C. difficile should be performed in immunocompromised children ≥2 years of age that are symptomatic and fulfil the criteria for diarrhoea • In the population aged <2 years, high rates of asymptomatic colonization should be taken into account, and testing is recommended only in case of high clinical suspicion^a • The algorithm for testing in children remains the same as per the adult recommendation • Laboratory diagnostics for CDI should be combined with diagnostics for other gastrointestinal pathogens relevant in the immunocompromised paediatric host • Clinical correlation should guide the interpretation of laboratory results and the decision to treat

CDI, Clostridioides difficile infection; ESCMID, The European Society of Clinical Microbiology and Infectious Diseases; GDH, Glutamate Dehydrogenase; NAAT, Nucleic Acid Amplification Test.

Infants are frequently colonized with both toxigenic and nontoxigenic Clostridioides difficile: Colonization rates in otherwise healthy infants range from 40 to 80% under 1 month, 30% under 6 months, and 14% between 6 and 12 months of age. The frequency remains as high as 22% in toddlers 1–2 years of age before declining to approach rates seen in healthy adults of 1%–3%,⁴⁸^,⁵¹ while colonisation with toxigenic strains of 13–14% between the age of 6 and 24 months.⁵² Asymptomatic colonization in this period of life may hypothetically be due to the relative absence of cellular pathways necessary for pathogenicity (toxin receptors or downstream signalling pathways) in the immature gut mucosa. The spontaneous eradication after the first year of life is likely to result from ecological competition with the adult-type microbiome, which suppresses the growth of C. difficile (ecological succession).⁵³