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Diagnostic approach

The following types of diarrhea may indicate further investigation is needed:

A severity score is used to aid diagnosis in children.

When diarrhea lasts for more than four weeks a number of further tests may be recommended including:

A 2019 guideline recommended that testing for ova and parasites was only needed in people who are at high risk though they recommend routine testing for giardia. Erythrocyte sedimentation rate (ESR) and C-reactive protein (CRP) were not recommended.