Clostridium difficile is the primary aetiological agent of antibiotic-associated diarrhoea. The faecal lactoferrin (FL) assay is a simple in vitro test which is highly sensitive to the presence of a marker of polymorphonuclear cells. We evaluated the use of the FL assay in conjunction with the C. difficile toxin assay in faecal samples obtained from 231 adult patients. The relationship between C. difficile toxin and FL in both negative and positive status was highly significant statistically (P < 0.001). Therefore, the FL assay performed simultaneously with the C. difficile toxin assay can help rule out asymptomatic carriage of C. difficile.