Clostridium difficile ribotyping network (CDRN): guide to services

The Clostridium difficile ribotyping network (CDRN) laboratories provide access to C. difficile culture and ribotyping, according to standardised criteria for submission of faecal samples.

About the Clostridium difficile ribotyping network (CDRN)

The Clostridium difficile ribotyping network (CDRN) consists of these participating laboratories:

  • Leeds (Reference Laboratory, Leeds General Infirmary)
  • Bristol (Bristol Royal Infirmary)
  • Birmingham (Heartlands Hospital)
  • Cambridge (Addenbrooke’s Hospital)
  • London (Barts Health), Manchester (Manchester Royal Infirmary)
  • Southampton (Southampton General Hospital)
  • Belfast (Royal Victoria Hospital) in N. Ireland

The CDRN laboratories provide timely access to Clostridium difficile (C. difficile) culture and ribotyping, according to standardised criteria for submission of faecal samples. Further DNA fingerprinting using multilocus variable repeat analysis (MLVA) can be carried out on request, if the criteria for enhanced fingerprinting are met.

This is a powerful tool that permits detailed analysis of clusters to determine closely related isolates, and so may help identify transmission. Antimicrobial susceptibility testing surveillance (metronidazole and vancomycin) is performed by CDRN on selected isolates.

CDRN is centrally funded and referring laboratories or hospitals will not be charged. The service is being used to investigate clusters of cases of C. difficile infection. We aim to provide timely information to help optimise the management of C. difficile locally.

The CDRN service should be used by hospitals or infection control teams in England to investigate any of the following:

  • increased frequency of cases or high baseline rates of C. difficile infection (CDI)
  • failure to meet a trajectory or target for CDI
  • increased severity or complications of cases of C. difficile infection
  • increased mortality associated with C. difficile infection
  • increased recurrence rate of C. difficile infection
  • numbers of faecal samples to be submitted will be agreed with the laboratory according to the extent and severity of the above

The CDRN service can help local teams to meet targets that have been set for reducing the incidence of C. difficile infection. Additionally, it will collect, via a mandatory request form, antibiotic risk and outcome data that can be used to provide more detailed information about C. difficile infection at a national level. Electronic requesting and reporting is being rolled out across CDRN, which increases the efficiency of the service and enhances data outputs.

The CDRN is separate from other arrangements for mandatory surveillance (specifically, case-by-case web based surveillance, and fixed number of isolates per designated week).

Accessing the CDRN service

CDRN electronic requesting system (ERS)

ERS allows NHS acute trusts to make electronic requests for ribotyping of Clostridium difficile at their regional Public Health England CDRN laboratory and allow electronic communications and results to be sent to the original requester, as well as other scientific and clinical staff at the requesting NHS Trust.

ERS is only available to users on the NHS N3 network.


For further details about the service, phone Professor Mark Wilcox on 0113 392 6818 or email

Published 8 August 2014
Last updated 9 November 2016 + show all updates
  1. Amended list of participating laboratories.

  2. First published.