Detection of Campylobacter species in faecal samples by direct Gram stain microscopy

Abstract

To evaluate the Gram stain with carbol-fuchsin counterstain for the rapid detection of Campylobacter species in faecal samples. In total, 842 consecutive diarrhoeic faecal samples were prospectively examined for Campylobacter species by Gram stain and culture. Campylobacter species were isolated from 84 faecal samples (all Campylobacter jejuni). Compared with culture, Gram stain microscopy had a sensitivity of 89%, specificity of 99.7%, positive predictive value of 97%, and negative predictive value of 99% for detecting Campylobacter species. The direct Gram stain method can provide a presumptive result within 30 minutes of receipt of a faecal sample in the laboratory with relatively high sensitivity, and at low cost. Laboratories in areas where Campylobacter enteritis is common and/or with limited resources for Campylobacter culture should consider adopting this as a routine method.