In Journal of Swine Health and Production, first-named author, Rodrigo O.S. Silva, and colleagues at the Veterinary School of Universidade Federal de Minas Gerais in Brazil explain that the aim of their study was to compare test performances of three commercial enzyme immunoassays (EIAs) for A and B toxin detection and that of a simple toxigenic culture protocol to the cytotoxicity assay (CTA) as the gold standard for diagnosis of Clostridium difficile-associated enteritis in piglets.

A total of 73 piglets submitted to the Veterinary School were included in this study. Intestinal content was collected from 62 piglets with diarrhoea and 11 piglets without diarrhoea, aged between one and seven days.

Vero cells were used in the CTA protocol to detect A and B toxins. Faecal samples were inoculated on cycloserine-cefoxitin fructose agar for isolation of C. difficile. The EIAs were performed according to the manufacturers’ instructions.

Sensitivity, specificity, positive predictive value, and negative predictive value were calculated for each EIA and for toxigenic culture against CTA.

The CTA was positive for 22 of the 73 samples (30.1 per cent).

Sensitivities of all EIAs and toxigenic culture for the piglet samples were low - between 41 and 64 per cent - whereas specificities were 80 per cent to 98 per cent.

Silva and colleagues conclude their results suggest that the EIAs and toxigenic culture protocol tested are not suitable for diagnosis of C. difficile infection in individual piglets.

Reference

Silva R.O.S., R.M.C. Guedes, M.X. Silva and F.C.F. Lobato. 2013. Evaluation of three enzyme immunoassays and toxigenic culture for diagnosis of Clostridium difficile-associated enteritis in piglets. J Swine Health Prod. 21(6):300–303.

January 2014